CAMaster Stinger 1 or ShopSabre 23

[todd werner]

Hi,

I am hoping some of you guys with more knowledge and experience than I have with CNC machines, could point out any benefits to one option over the other, that I'm not seeing. Also any thoughts on my assessments.

My use of the machine will be purely hobby wood working. My son may be using it occasionally for some aluminum parts for robotics, but mostly it will be used for woodworking.

Price is less than $200 apart on my two choices below with identical software.

Stinger SR-23
25x36" cutting area with gantry overhang on side. 7" under gantry with 9" Z-travel. (This is with their 2" gantry lift)

Options it would include are:
a laser cross hair for xy zero'ing
a Z-touch plate for Z zero'ing
a 2nd mounted Z touch plate for tool length checking after tool changes.
a 1.7KV spindle
a pneumatic counterbalance.

The Shop Sabre 23
30 x 40" cutting area with gantry overhang on side. 5" under gantry with 6 1/2" Z-travel
A mounted Z touch off switch for tool length checking after tool changes.
1.7 KV spindle


CAMaster Pros I see:
1) Z-touch plate included at the price point.
2) Laser
3) More room under Gantry.


Shop Sabre Pros I see:
1) 5 inches wider and 4" longer
2) A Mitsubishi VFD for the spindle vs maybe a Delta VFD. (Both are likely equivalent to me)
3) 25mm rails. (I'm not sure what the CAMaster has on the Stinger 1's. They use 25mm on every other line.)


I don't care about the ShopSabre having a steel gantry cross bar. The Stinger 1's gantry will be plenty stiff at that length and aluminum actually cost more. Also, the vertical supports on the Stinger have a more impressive design to them with some perpendicular pieces. So let's ignore the material difference there.

I don't know if adding 2 inches to the Stinger's gantry height will decrease rigidity significantly. If it won't harm rigidity, the gantry height vs the surface area are a wash to me.

I think not needing a counterbalance for the 1.7KV spindle is an advantage for the ShopSabre because I won't need to run my compressor. I assume it means they have a stronger stepper motor. The ShopSabre uses 2500 ounce/inch motors. I don't know what CAMaster uses.

I don't know if the ShopSabre having all ball screws matters to me.

I think the Mitsubishi VFD may be a small advantage for ShopSabre.
I think the two touch plates of the Camaster beats the single tool height measure on the ShopSabre for convenience, but it's a small advantage.

The ShopSabre definitely has 25mm rails. I'm not sure what the CAMaster has on the Stinger 1. Camaster uses 25mm on every other line. I suspect ShopSabre doesn't want to have to stock a smaller size rail, but that may be a small advantage for them.

So which of the features do you guys think favor one machine over the other, and which seem most important to you? Both companies seem very nice. I will admit, I feel like ShopSabre copied a lot of their 23's design from the CAMaster Stinger's. I don't admire that, but if you think they copied and also improved on the design, I'd like an honest opinion on that. And if you know of any complaints or flaws in either design, I'd like to know about that too.

Thanks for your advice!
Todd

PS) I've been a member for a while, but this may be my first post. If it isn't, it's my first in a long time.

[Jim Becker]

(There's a nice Stinger I for sale in the Camheads forum...'just sayin...includes the 4th axis capability and is 24x48 capacity)

I don't know anything about ShopSabre, but have a Camaster machine on order based on the recommendations of several folks that I trust. I'll be down there end of next week for training and may even get to see my machine "born", depending on timing. At least both companies are US manufacturers and that's appealing to me for sure.

[Dan Schmidt]

I'm interested in what you learned comparing Axiom to Camaster. I'm on the market as well but just beginning the research.

[todd werner]

Hi Jim,
I saw that post. I registered there 10 days ago but still don't have permission to view pictures or post a response on the website. Maybe because I'm not an owner, or maybe I registered wrong somehow.
There's no price listed on that Stinger and it's in Arkansas, which is tricky.
Which Camaster did you order, and between the two machines I'm looking at, do you see any mechanical/design advantages of one over the other?
Thanks,
Todd

[Brad Shipton]

The important part is the quality of the machining and how well it is assembled. You cannot see that from a spec sheet. From the spec sheet they both will do the job. Shop Sabre uses that rail to simplify their life when it comes to supply. If you look at the loads on this rail, a 25mm is not necessary, but when you look at the price difference where they import them from in China you will see it makes no sense to stock multiple parts. If I were in this market I would talk to Gary about one of his machines or go talk to people in person that own either of these machines. I suggest you watch Gary's retrofit videos a couple of threads down. This will give you some more ideas what to be looking for.

[todd werner]

Hi Dan,

Axioms Elite model seems to imply it's servo driven, saying it has "They offer the speed, torque and precision which can only be found in servo-driven machines. Cut at up to 320 IPM while maintaining repeatability of .05mm!" But they don't tell you what they use. It also has a liquid cooled spindle, which may not be bad, but seems like the same cost saving tactic used to bring down the price of a lot of Chinese CNCs and they do look like they come out of the same factory as my Steel City bandsaw or my Grizzly Jointer. Those are great tools, but they're also simple tools, unlike a CNC machine. Sorry I can't offer anything more than my impression that the ShopSabre and Camaster lines are better made.

[Dan Schmidt]

Hi Dan,

Axioms Elite model seems to imply it's servo driven, saying it has "They offer the speed, torque and precision which can only be found in servo-driven machines. Cut at up to 320 IPM while maintaining repeatability of .05mm!" But they don't tell you what they use. It also has a liquid cooled spindle, which may not be bad, but seems like the same cost saving tactic used to bring down the price of a lot of Chinese CNCs and they do look like they come out of the same factory as my Steel City bandsaw or my Grizzly Jointer. Those are great tools, but they're also simple tools, unlike a CNC machine. Sorry I can't offer anything more than my impression that the ShopSabre and Camaster lines are better made.

Absolutely no problem if you are not sure. Anyone else who is knowledgeable about these machines and have any facts?

Dan

[Jim Becker]

Hi Jim,
I saw that post. I registered there 10 days ago but still don't have permission to view pictures or post a response on the website. Maybe because I'm not an owner, or maybe I registered wrong somehow.
There's no price listed on that Stinger and it's in Arkansas, which is tricky.
Which Camaster did you order, and between the two machines I'm looking at, do you see any mechanical/design advantages of one over the other?
Thanks,
Todd

Send a PM to James McGrew (here or on CAMheads) and ask that your account be approved. I think that the notifications of new registrations sometimes gets missed by the administrators there as it seems to be a common issue.

After a lot of thought and angst and manic enlightenment...and driving the sales dude nuts by continual changing to the "next machine up" :D ...I ended up ordering the Stinger II SR-44. I did start out with the Stinger I SR-24 as I was, at the time, comparing with the Axiom 24x48 Elite machine. I chose Camaster because of both recommendations and because I perceived it to be an extremely well built, heavy and welded frame machine (that included the Stinger I), their use of WinCNC (not sure what ShopSabre is using for control...if it's proprietary, no way would I be comfortable, frankly) and because the setup was completely turn-key and tested before it ships. The Axiom Elite seemed to be a nice machine, but it's mostly made off-shore and I didn't perceive it to be as heavily built as the Camaster. I only went larger because I plan on making the CNC part of the monetization of my shop as a part time retirement business since I left the full-time workforce last fall and became a full time "house husband" to enjoy the fruits of my labors for the past 38 years. It's likely that most of what I'll be making would easily be accommodated by the smaller machine, but since I had the ability to go to the 4x4 and enough room to move it slightly to tile a full sheet if necessary, I did that. The cost didn't double with the size doubling, either. Again, I really don't know much about ShopSabre and don't know anyone personally who owns one. It's good to see that they make their machines "here" like Camaster, however, and they appear to be nicely appointed. And yea, very similar to the school bus yellow offerings from Georgia... :)

[Alan Marchbanks]

Todd,
I have the Camaster Stinger 1, 23, Equipped nearly identical to the one you are considering but mine included the recoil. Camaster recommends the counter balance and mine has it. Once you apply air pressure to the counter balance it does not consume air volume that will cause a compressor to cycle. When charged, the air pressure in my system has no noticeable drop in pressure and some jobs have run for several hours. I like the machine very much and recommend it. Tech support from Camaster has been exceptional. I've had it for just over two years. Can't speak with personal experience about any other machine. A last thought, I have the 1.7 spindle and do not think water cooling is necessary. I,m sure you'll enjoy whatever you get.
Alan

[todd werner]

Thank you for the responses guys.
Brad,
One of the reasons I posted this question here and at the CNC zone is that I don't know enough about the internals to tell where one company has an advantage over the other. I didn't know Gary sold machines. I did figure out he's very knowledgeable and the Sidewinder with tool changer machine he built looked impressive (and also out of my price range). I also saw that he may have been familiar with at least one of these models. Because of that, I actually PM'd him to ask this question. I got the sense he dislikes one of the companies for possibly poaching ideas, but he didn't offer me any specifics about which one had superior control boards or drives or such, which is what I'd love to learn, as well as the importance of the "luxury" items on the Stinger. I'm not sure I'll understand every answer given either, but if I don't understand, I'll learn enough so that I do before I buy.

Jim,
Thank you for the tip on who to contact at CAMHeads.
I'm almost sure the ShopSabre is also a WinCNC machine.

Thanks Alan.
Do you leave an air hose hooked to the machine at all times? Given what you said, I could hang an 11 gallon harbor freight tank and put a line from that to the CNC. Then all I'd have to do would be to charge it periodically.

[eugene thomas]

I have dealt with both company's. If buying new cnc now would be yellow. Good luck with your journey...

[Alan Marchbanks]

Todd,
I happen to leave mine plugged in all the time, but I think a charge tank would work fine, sure worth a try if you don't have air plumbed near your machine.
Alan

[Jim Becker]

I added a dedicated air drop for the CNC from my air system with a flexible hose (one I had sitting around and don't use normally because it's an old-style heavy rubber do-jobbie) so that if I need to move the machine out for tiling something larger I don't have to futz around with the air supply as there will be a small coil of hose right there with a coil of power cord. The air cylinder that Camaster has for the Spindles helps keep the heavy load off the Z axis motors when raising the spindle and they should wear less and be more accurate as a result. As others have indicated, it's not an "air user" in any way and doesn't even require a substantial air source. It just needs to be regulated to 90 psi (which is less than many compressors provide) and should also have a filter on it.

[Mark Bolton]

From my perspective as an owner of a Shopsaber 408 Pro I can only tell you that you will find an extreme bias here to Camaster which is completely fine because this post may well be deleted

We have had a 408Pro on the floor for nearly 2 years with ZERO problems from their end (only operator error). They have responded to numerous questions nearly immediately via email and the support and communication from the onset of the quoting process, through manufacturing, delivery, acceptance of delivery, and post, have been completely consistent. There was no droop in contact after checks were cashed, after the sale, after delivery. If I mail them right now on a friday night I'd guess Id have a response before they close.

I stated this in another post that was deleted, and I could search back through my emails and phone logs, but I didnt find that to be the case with other manufacturers that were contacted for a machine purchase. Some never saw fit to return a phone call or email or even provide a detailed quote.

Just giving you our personal experience. Others here, and in this thread, have had different experiences but that is ours.

[Jim Becker]

Mark, it's good to hear that you've had a good experience with ShopSabre and I thank you for providing it. I personally wasn't aware of them until the OP asked earlier and I took a few minutes to browse their site to see if I could help him out.

[Mark Bolton]

Mark, it's good to hear that you've had a good experience with ShopSabre and I thank you for providing it. I personally wasn't aware of them until the OP asked earlier and I took a few minutes to browse their site to see if I could help him out.

Well thats sad to hear Jim, because there are other options out there. I understand that a few (or more) here may be somewhat biased but as you well know, this gray area between the hobby and the commercial world is a fickle spot in which I would often times not want to be a vendor.

For instance, I just spoke with a shop (metal not wood) that took delivery of a DMG MORI that probably cost 300K and had a couple dents in the covers and scratches from shipping and they dont care. The guts is what matters and the machine will run in the profit margin for years. Its a wonder we in the low level world even get a return phone call with dial calipers and feeler guages on consumer level table saw tables.

Our machine is cutting at .001 two years after we have run the guts out of it. AND likley made a few mistakes that shoiuld have taken it out of tolerance but are to no issue.

There is a gross bias here. And when I say gross bias,.. I mean GROSS bias. Its flagrant.

Its not to say the alternative is not a great option, but the bias is really, really, over the top.

Ready for the delete lol.

[todd werner]

Hi Mark,

I think one or two bad experiences spread on the web can bias an entire board, so companies need to be very careful not to let that happen. ShopSabre, at least in my minimal experience, hard sells their product as the ultimate, which always rubs people who do their own research the wrong way. As an example, because they know I'm comparing their machine to CAMaster's, someone there said they heard that CAMaster is moving to all ball screws on their top of the line machines, implying that clearly the SS-23 is better since it uses ball screws not rack and pinion.
It's also bad to copy someone else's design and then say something like, "they're always chasing us on innovation and quality". I can look and see who copied who based on when a machine was introduced. The web makes it easy to figure stuff like that out, so it's bad practice now days.

The people there do seem very nice, but it feels like someone is trying to sell me a timeshare, and I don't get that from CAMaster.

None of what I just wrote means the CAMaster is better than the ShopSabre or that the Shopsabre is better than the CAMaster. It just means I don't like their sales style, but I'll choose based on the machines.

So I'm still trying to figure out which is the better machine for me. Both are good, and nobody here has ever said a specific component on one or the other is inferior or superior. Someone did imply the ShopSabre rails are Chinese and cheap, but it's so off-hand, I don't know how to take that. It's not like anyone said: ShopSabre uses 25mm Chinese rails and CAMaster uses 15mm rails by _______ which are better. I wish someone would be that clear.

I still don't know which uses a better stepper motor, or higher quality rails or controllers or such. Maybe nobody here does either.

But I'd still like to hear opinions on whether the fixed Z touch plate is better than the Z-touch switch. Does a fixed plate it ever break small bits because there's no give to it?

Or will the gantry flex more if I order it with the 7" or clearance?

Both use Mitsubishi VFDs and the same spindles. Both look really solid and well engineered. As of now I'd be deciding between more surface area vs more height and a pneumatic counter balance (since that sounds like a plus, not a minus as I initially thought).

[James Biddle]

I've now ran both company's (their bigger offering) machines and you really can't go wrong with either one. Camaster and Shopsabre could be fraternal twins. Both are American made, run WinCNC, have a one-piece welded frame, have HSD spindle options, etc. They carry much of their larger machine design and technology down into the smaller machines. They both stack up well against bolt-together hobby frame machines and questionable quality Asian imports.

[Jim Becker]

Todd, one thing on the gantry extension...pay attention to the note that getting the extension does not increase the Z-axis travel. My take on that is that the higher gantry is more for "eyesight" since it doesn't alter the cutting capabilities on the Z-axis. Here's the text from the Stinger Options Document:



GantryLift (AllStingers)
This option gives you 2” more of work room under the Gantry. With this option, the Stinger I work room is 7” insteadof 5” and the Stinger II & III is 8” instead of 6”. This option DOES NOT increase the Z travel of the machine. The Z axistravel on the Stinger I is 9” with 5” below the gantry, on the Stinger II and III, it is 11” with 6” below the gantry.

[Bruce Page]

Todd, I have the Stinger 1, SR23. I bought it new 5 years ago and haven’t had a single problem with it. I am a retired hobbyist so I don’t push it hard. I’ve only needed to contact customer service once and the problem turned out to be operator error. I have no bias toward ShopSabre, I don’t think they were selling the ShopSabre 23 when I was doing my homework.
As mentioned, the counter balance only needs to be pressurized and does not “use” air. There is a pressure regulator mounted on the machine, you only need to run air to it, mine is factory set at 36psi for the 1.7kw spindle.
The Z touch plate and the Z set switch do basically the same thing but for different reasons. The touch plate works well for setting a single cutter relative to your work piece, table top, etc. The set switch, or FTC as Camaster calls it is used when you have multiple cutters used in one piece, e.g., end mills, ball mills, v-bits. The machine will prompt you when it’s time to change a cutter, measure the Z position of the new cutter and go back to work. It is a very cool feature over just a touch plate. I have never broken even very delicate bits using either method, however I do slow down the Z ipm drop rate with delicate bits.

[todd werner]

Todd, one thing on the gantry extension...pay attention to the note that getting the extension does not increase the Z-axis travel. My take on that is that the higher gantry is more for "eyesight" since it doesn't alter the cutting capabilities on the Z-axis. Here's the text from the Stinger Options Document:

Hi Jim,

That's an interesting point. The advantage of the taller gantry might be the ability to build jigs or parts holders without losing clearance. For example, if I want to use the CNC to shape a Laskin Bevel on an acoustic guitar, I could make a body mold/clamp that mounts to the deck, and the guitar sides would be supported everywhere except where I wanted it to carve the bevel.

The disadvantage might be that I couldn't have the machine cut T-track slots in the deck, because the spindle could only get to within 2 inches of the MDF.

So what do you think? Does 5" of travel below a 7" tall gantry mean a bit would have to stick out at least 2 inches just to touch the deck? If so, does everyone with gantry lift option use a super thick spoil board?

Hmmm, if you put on the thicker spoil board, can you still use the rapid tool change touch plate mounted to the side, or will spindle body hit the spoil board before a short bit would reach that Z touch plate. I suspect the tool length touch pad is adjustable in height, but you may be right. There my not be an advantage to the gantry lift if I can keep my jigs fairly close to the deck on a standard height gantry Camaster or Shopsabre.

[todd werner]

Hi Bruce,
I saw that feature on Javi's Wood Shop video on YouTube and it looks great. The ShopSabre does the same thing, but there's a switch mounted to the top of the electrical box at the foot of the machine. So it presses that switch down to measure the tool length after each bit change.
I assume they're equally accurate. The plate seemed like it might break a tiny bit, the switch seemed like it might break, but I'd call them a wash.
What the ShopSabre doesn't include is a touch plate to set your table height, it would be almost $400 to add that. No laser on the ShopSabre either.

Does the gantry on the Camaster hang from the rails under the steel tubing? The ShopSabre rails are on the sides like the ones on the Stinger 2's. The Stinger 1 design seems more protected from dust and metal shavings, but possibly not as strong a design. Strong enough I'm sure, but I'm wondering why they designed it that way. Any ideas?

[Brad Shipton]

Time to take a drive so you can touch one and talk to the users. There is a map on the camheads forum of where they are, and I am sure SS can provide you some names too. You might even think about the Shopbot.

I would bet the Cammaster linear rails are Hiwin just like SS and those are made in Taiwan. I know for certain that is what are on mine, because I tracked down the part numbers and figured it out. The industrial machines use brands like Rexroth, Thomson, SKF, FAG and other high end names. Those are about double the cost, so that is why you do not see them on entry level machines. Are those any better? Depends on your goals. To get your accuracy to around 0.015" - 0.025" is not all that difficult, but to get less than that you have to be a bit more meticulous about details.

Both Cammaster and SS are using reputable steppers and unless you know the gearing, you will not be able to figure out if either can achieve the speeds stated. I suspect the SS is using a Sanyo Sanmotion stepper that is one or two sizes smaller than those on my 4x8 SS machine. For this aspect of the machine you will need to get comfortable with what the manuf is telling you or rely upon the experience of others using these machines.

I like the Z axis balance on my machine and it does not use much air. I mounted a mister assembly to my z axis for cutting aluminum and some DC parts. That adds a bit of weight, but I was able to counter that easily by adjusting the air pressure.

I have a touch off pad for setting the Z axis height, and one for the tool changer. These are not incredibly accurate, but they work for many. You need to look at how these work. The ones on mine have three electrical contacts inside, and when the electrical current is broken that is the reference height. I use a Techniks manual gauge because I am too fussy. It does not take that much time once you are used to it. There is a discussion of the Tormach SPU-40 probe accuracy online. That is what SS is using now for their Z axis touch off. I have one hanging on my wall I will sell.

This will boil down to features, word of mouth, and your impression of the machines from talking to the salespeople.

[Bruce Page]

Does the gantry on the Camaster hang from the rails under the steel tubing? The ShopSabre rails are on the sides like the ones on the Stinger 2's. The Stinger 1 design seems more protected from dust and metal shavings, but possibly not as strong a design. Strong enough I'm sure, but I'm wondering why they designed it that way. Any ideas?
The rails are mounted to the bottom of the tubing on the Stinger. I don't see that as a problem but I am not a machine designer. It is plenty stout.

[Gary Campbell]

Todd...

I tried my best to avoid this thread. You did PM me and since I have not owned either of the machines in question, I did not comment. When he asked about a previous negative comment, I would simply stand by those comments. I don't know if you have figured it out yet, but we (other CNC users) cannot give you the answers that you request. That would involve us making a decision for you. Think about it.... it's the freakin internet!

If you want to know my opinion, read the thread I wrote on the CAMheads forum in the FAQ section titled "Buying a CNC? Do your homework!"

In my opinion, most of the assumptions you make are not the ones that I would make. Also, following the lead set by most pre purchase CNC wannabees, the vast majority of things that concern you now, will not be the things that concern you once you gain experience. Many of your questions (to me) are similar to " are brand A apples better than brand B oranges?" In other posts you answer most of your own questions with other questions. That said there are few questions that I can answer.

An air counterbalance allows a faster response from the Z axis be "counterbalancing" the weight of the Z assembly. Noticeably faster 3D cutting, if you do that sort of cutting and allows faster retracts without loosing steps. The Z axis still has to fight mass and inertia, but not gravity.

Steel vs aluminum: Equally sized steel is cheaper and stronger. Steel costs more to machine than aluminum, virtually eliminating any savings. So the real questions are: Are they equal sized? Do they have similar machining? Are the surfaces for the rails machined and set to datums? Do you actually think either of these companies would produce a gantry that visually deflects and still be in business?

Gantry height: All things being equal increasing the gantry height will always increase deflection. That deflection will seldom be in the gantry beam, it will usually be in the side plates. That's why stronger gussets are usually provided. In most cases the collet nut will travel to the factory table, as there is a couple inches of unused travel on the shorter heights .

Spring loaded tool measure switches are always better than the flat plate conductive type.

If you have questions about the control components find an online picture or have your sales guy provide one. You will want to know if they are using good products and methods.

It does not matter if they mount the rails on the top of the frame, bottom or side. What matters is how rigid are the connections, are they precision machined and how strong are the components.

In reality, most of us do not know the answers to most of your questions, as they don't matter much. Take linear bearing blocks for example. The maintenance you perform will have a much greater effect on their service life than the brand. Only a companies salesperson will tell you that brand A is better than B. In most cases we cant. Like Mark says, most here are biased towards the brand they purchased, just like he is.

Like most before you, you are suffering from "paralysis from analysis" Find a machine you like from a company you can trust, and order a machine!

[todd werner]

Hi Brad,
The Tormach probe seems like an expensive way to do things when a fixed conductive plate would work, but good to know what it is. I can't tell if you think one is better than the other from your post. You seem to say both are not accurate enough for your purposes.

I was thinking I would get a Shars or APM tool setting gauge if I get tired of paper and feeler gauges.
I found information on the rails in a brochure. You are right. ShopSabre uses Hiwin rails and bearings. So other than the size, the two are a match. Seems like they're a match on most things. Can I ask what CNC you have?

Bruce,
I don't see it as a problem either. I am a little curious as to why they did it that way and thought you might have an idea. Maybe so the gantry uprights can be closer to the frame. Just curious about that, not thinking it's a problem.

Editing, because I had this open when I got a phone call, and didn't see Gary's comments until after I posted.
Gary, thank you for commenting. I got the sense you were hesitant to do so based on some prior experience with one of the companies.

Nice to know about the switch vs plate accuracy. I'll read up on it a little more.

Also, thank you for explaining the air activation part.I'll go read that thread if I can find it. Then I'll crash for the night. I am trying to do my homework, but it sounds like I'm not asking the right question. In B-school they used to tell us it's important to know what you don't know. I'm trying to learn that. Thanks.

[todd werner]

You know Gary,
You could have just aimed me at that thread a day or so ago. Might have saved a few guys here some frustration with me :) And by that I really mean I would have tried to compare each of the machine's equal components, such as steppers to steppers. Since dimension wise they are both more than adequate for me, it sounds like I'd do best thinking of them as pre-assembled kits that come with some company made parts, some important components, and company support. For me, the design differences of ball screw vs rack/pinion aren't going to be as important as the implementation.

I'm going to be taking a class on CNC basics this Fall at a local technical college, so I expect to put time into learning to use this, but I don't plan to wait until after the class to purchase, so I trying to get oriented.

In a way this feels like a John Deere vs Kubota tractor choice. I've owned both, and both make great products, but there are tradeoffs with each. With Kubota I may get slightly more features or capability for x dollars, with Deere I may get slightly less tech but more reliability and a company that overnighted a steel hydraulic line so I could finish a job the next day. Which is more important depends on the user.

I've already stated a preference for low key straight forward sales speak. Doesn't mean I've made a decision, because I clearly have more questions to ask the sales guys, and I'll attribute the sales style difference to culture and age and such. I also suspect the style I don't like will adapt to me, because the people there are nice and will realize I hate a hard sell.

Thanks again,
Todd
Edited because I have different questions now.

[Brad Shipton]

Todd, I have the same machine as Eugene. A Shopsabre RC8. I do not share my personal feelings about the machine online because it would not be fair. I am not your typical consumer, and I should have bought something twice as expensive from a company with staff engineers. I am about to start a retrofit project to upgrade some aspects of my machine.

I have never used a conductive plate as a tool setter, so I have no basis to say how well they might work. From Bruce's comments I doubt I would like that method.

I found the automatic gauges on my machine could be .005" to 0.008" off at times. To determine that I compared measurements from both the automatic tool setter and the analog gauge. I make cabinet door parts, and dovetail drawers on my machine and errors like those lead to more joint repairs than I like. I dropped my old Z axis table measuring tool, and while I was waiting for parts I got used to using my manual one for everything. I repaired the old one and the new one is hanging on the wall, but I never seem to use them anymore. I can reset the height of all 5 tools hanging on my rack in less than 5 minutes, and that is fine for my one man shop. I use the analog one on this page http://www.techniksusa.com/metal/cnatpsg.htm Edge technology makes a more cost effective option than that, but it is much taller and generally for steel milling machines. http://www.edgetechnologyproducts.com/pro-touch-off-gage/

[Mark Bolton]

Hi Mark,

I think one or two bad experiences spread on the web can bias an entire board, so companies need to be very careful not to let that happen. ShopSabre, at least in my minimal experience, hard sells their product as the ultimate, which always rubs people who do their own research the wrong way. As an example, because they know I'm comparing their machine to CAMaster's, someone there said they heard that CAMaster is moving to all ball screws on their top of the line machines, implying that clearly the SS-23 is better since it uses ball screws not rack and pinion.
It's also bad to copy someone else's design and then say something like, "they're always chasing us on innovation and quality". I can look and see who copied who based on when a machine was introduced. The web makes it easy to figure stuff like that out, so it's bad practice now days.

The people there do seem very nice, but it feels like someone is trying to sell me a timeshare, and I don't get that from CAMaster.

None of what I just wrote means the CAMaster is better than the ShopSabre or that the Shopsabre is better than the CAMaster. It just means I don't like their sales style, but I'll choose based on the machines.

So I'm still trying to figure out which is the better machine for me. Both are good, and nobody here has ever said a specific component on one or the other is inferior or superior. Someone did imply the ShopSabre rails are Chinese and cheap, but it's so off-hand, I don't know how to take that. It's not like anyone said: ShopSabre uses 25mm Chinese rails and CAMaster uses 15mm rails by _______ which are better. I wish someone would be that clear.

I still don't know which uses a better stepper motor, or higher quality rails or controllers or such. Maybe nobody here does either.

But I'd still like to hear opinions on whether the fixed Z touch plate is better than the Z-touch switch. Does a fixed plate it ever break small bits because there's no give to it?

Or will the gantry flex more if I order it with the 7" or clearance?

Both use Mitsubishi VFDs and the same spindles. Both look really solid and well engineered. As of now I'd be deciding between more surface area vs more height and a pneumatic counter balance (since that sounds like a plus, not a minus as I initially thought).

I dont disagree that the hard sell never feels very good when your on the buyer side of the relationship. I dont like it either, but being in business unfortunately until your in a very comfortable position you almost always are striving to close the deal and close it quickly to avoid investing hours and hours of uncompensated time. That said, my personal experience didnt seem all that pressure filled but perhaps thats because we are always dealing with salesman. Try getting on Felders sales call list. They will make sales calls multiple times a year, every year. Cant blame them. It think it can go either way. In our decision we built our own base quotes and shipped them off to multiple mfr.s the vast majority of which went completely unanswered. No call back, no return email, no nothing. Many of those were the big industrial brands that were likely out of our range anyway but the same happened with many of the lighter industrial manufacturers as well.

I think their pitch of buy your second machine first is a very wise one. Most of the complaints I have read here and elsewhere about virtually any manufacturer look, from my perspective, to be cases where we are all trying to be cost conscious and the individual opted down a level or two to save money thinking they would be operating a peak performance on the specs and then after getting their machine realized they should have budgeted a bit higher and moved up a level or two or traded out a couple of desired accessories to get to a bigger/beefier/faster machine. Then you have the complaints that are just plain issues where the purchaser completely misunderstood what a function or capacity was from the start and now just wants to get on a forum an ride a company down for their own oversight.

We came close to making a few of those mistakes ourselves in trying to add all sorts of accessories and thankfully we were lucky to realize and just cut back on the options and pour the money into the best base machine we could.

We are complete CNC noobs but kind of to Garys point, I think a lot of the little details people get focused on in comparing specs will be the least of your concerns when you get up and running.

Im in James' camp in that Im sure both machines are equally good. For me personally I prefer heavy steel over aluminum. I watch our machine breaking down sheets and we normally run wide open and Im thankful for that weight. When we first set up the machine the rapids were scary. Now, I watch it and think of the machines running 800ipm, 1100, and Im wishing we could go faster. But this is plenty fast.

I personally like the touch switch. We have touch switch for auto Z, tool height setter on the tool changer, as well as a spindle mounted touch probe (which we rarely ever use). The only issue I have with the ATC tool height is it has a pad that looks to made of UHMW or something like that and when setting heights on super sharp tools (insert V bits for instance) they will set a touch low because the sharp tip will poke into the plastic slightly. The Auto Z switch dosnt have a soft pad so its spot on every time though I did make some adjustments in the wincnc.ini for the offset of the touch switch to get it closer.

They are all tough decisions when your spending hard earned dollars. I personally dont focus on such specs like what rails are they using, bolts, etc. and so on. Most machines that would even make your list are all using quality components across the board. It begins to lead you down a path of expecting Ferrari specs when your budget is for a mid-to-high quality toyota but thats just my opinion.

[todd werner]

Mark and Brad,
Thank you. That makes a lot of sense.
I edited my last post.
No more questions about the two specific machines until I know more about CNC in general. Time to study.

Editing this post to just to say I'm especially grateful for the explanation on the z height option stuff. More for when I'll try to do Vcarve on a sign vs a dovetail, than for how it might influence what I buy. Information like that points out that I have to learn more to ask the right questions.

[Brad Shipton]

Todd, my guess is you are dealing with the new sales guy at SS. I do not know him so I should not say this, but he kind of reminds me like a used car salesman for some reason. I dealt with Brandon at SS and I bet Mark did too. Brandon is a very good salesman. Answers questions, and is good at getting back to you. They are in their new shop now, and I suspect things have changed a bit as a result.

[Gary Campbell]

Todd...
Sorry, I made the assumption that since you were looking at CAMaster machines, you had looked over that "FAQ" section. There have been over 20K views of that thread, around 12 guys may have listened. :)

I agree, the ballscrew vs. rack & pinion usually makes no difference to me. On small (< 3' lengths) tables I prefer screws because it lowers costs to the customer, especially at higher reduction ratios and since I only sell to experienced users that know exactly what they need and have found that no OEM provides that combo in a small format machine, they prefer that additional cutting power over a published speed rating.

What does make a difference is: what is the final drive ratio? How many motor turns per inch of travel? Most commonly used R & P will use 1.25 to 2.75 revs per inch. Most ballscrews will be 2.5 to 6. Motor rpms are limited. Torque is fixed. Performance, which should be the mix of torque and speed, will be a product of those numbers. Few if any know those numbers. And it may not matter if the machine does the job they want it to.

Most experienced users find that they don't care about the mfgr provided numbers, because they are just like paint on fishing lures: Made to catch fishermen, not fish. What's important is: does it catch fish? Only use will prove that. Same for CNC. How does it cut? At what speed can it cut in my material and hold a given tolerance?

The one number most small CNC (machine size not mfgr size) do not offer is: "Our machine will cut (xxx) material, using a 1/4" bit at 1/4" depth at (X) inches per minute and hold (.00X") tolerance. This is easily tested on any machine using 6" squares and 6" diameter circles and measured with a digital caliper. It is the one item that can provide the most info to any experienced user. That spec is what divides small machines into their price classes. The numbers would surprise many.

Someone mentioned a machine I am using as a long term demo project. It is an inexpensive import that inspection shows has good machining but poor assembly and low "plumb, square, level" measurements. Good parts, but poor assembly. A few hours of machining later and that machine, with NEMA34 closed loop steppers and Centroid control will outperform both you mention at a lower price. Add WinCNC and it will outperform both at a higher price. WinCNC and Centroid are so far advanced over all the other DIY controls that it is hard to explain. And I do have speed/tolerance data for my customers.

I really feel that the "Find a machine that you like from a mfgr you can trust" is the best advice you can get. If in fact you really get involved with this craft, and once you have a few years experience, like most, you will upgrade. If you buy from the same company, you did well on your first pick. If not, you are 50/50. Better than most. A 500 batting average will keep you in the bigs.

[todd werner]

It's interesting to hear how you define performance.

I think my involvement in the craft will be strictly as a hobbyist user. I have no desire to build my own CNC because I have too many other projects. If I factored in how much I value my time to do those, it couldn't pay off for me.

So I'll defer to experts like you and Camaster and ShopSabre and ShopBot, to design and build the machines. I will learn enough to make an educated purchase, but then I plan on learning to use it on my projects (and the ones my wife is waiting on 🙂 )

Now I have to learn about spindle power and how to buy enough but not too much for the machine, steppers and loops, and controllers.

[Bruce Page]

Now I have to learn about spindle power and how to buy enough but not too much for the machine, steppers and loops, and controllers.

More is better when it comes to spindle power. I went with the 1.7kw (2.28hp) and have had no regrets with it. It has never bogged or complained. I was told that the 1.0kw was a little underpowered for routing and more suited for engraving. The 3.0kw would’ve been nice but it seemed like overkill for my needs and was an additional $500.

[Jim Becker]

Like Bruce, I selected the 1.7kw spindle for my machine and expect it will do just fine with the kind of things I'll likely be cutting, which will be both hobby and some business focused work.

[todd werner]

I am 100% sure the 1.7Kw would be enough for me. Everything I'm reading says in many ways even the 1Kw is more capable than a router, and I would I'd be OK with a router.

So really I'm reading about motors and such and wondering if I'd be better off with a 1.7Kw and the stock motors, versus looking into a motor upgrade with the 1KW spindle.

If I understand what I'm reading, with a stepper motor, there's a risk they slip and lose position if there's too much resistance. So I'm trying to figure out if a motor with more torque is less likely to slip, or if it's just faster or less likely to get stuck. I'm going to ask the two companies if there are any options to upgrade to a closed loop or hybrid stepper system. https://www.motioncontroltips.com/open-loop-stepper-motor-versus-closed-loop-stepper-motor-systems/
I don't want a bigger model, the two I'm comparing are really close to the perfect size for what I want to do and where I'm putting it. I just don't want to feel any need to upgrade for as long as possible and I see a lot of hybrid or closed loop stepper systems being discussed, and they do come in NEMA 23 sizes.

[Jim Becker]

Todd, maybe you're over thinking this because "what you're going to do" with the machine is going to dictate whether or not things like heavier motors will pay off. If you're not going to be driving the machine hard, then heavier motors just add cost. Of the three or so CNC brands you're potentially looking at, the setups they build in as standard seem to be pretty appropriate for the size machine you're considering. I personally feel that a spindle is worthy for a variety of reasons, but "beefing up" other things might not matter. As you note, there's a lot of "techie talk" about various motors, etc., but you really have to ask yourself if that's relevant to your situation for a small machine to enjoy in your shop. Remember, you said you originally were considering one of the very nice kit machines, rather than these much heavier units. Honestly, this almost really comes down to "what color do you like?" relative to what manufacturer makes you feel the most comfortable.

[Gary Campbell]

Todd...
I read that page you linked to and will tell you that even tho it is sprinkled with some facts it is mostly marketing hype intended on selling their higher priced motors and drives. Closed loop steppers are not servos. Anyone that is selling steppers and uses the term servo is B.S.ing you. If you have a stepper motor, lets say 400 ozin (holding torque @ zero rpm) rated and you put an encoder on it you gain ZERO torque, and by extension ZERO acceleration. You only gain the ability to have the machine alarm out (similar to an estop event) if the actual position is more encoder counts away from the commanded position than the "alarm setting". When/if the load reduces far enough an encoder equipped stepper will force its way back into its position.

Torque is like lever "power" around a fulcrum. It is the ability to accelerate a load. Power is the ability to keep a load moving. Torque is required to get your gantry up to speed and what keeps it from losing position when the bit hits a rock hard knot. The faster a stepper moves the less the torque becomes, until it reaches a certain rpm then it falls to near nothing. In your world you will have to keep the load on your bit under that which would cause you to lose steps. This is true if you have a closed loop system with a minor error and an alarm, or a standard stepper that moved off course and just kept cutting on an erroneous path. Either way your part is shot.

I don't know if either of those models have a closed loop option, but if they do and you purchase it, you will still have to learn to keep loads appropriate. "S"ome companies that used a lot of closed loop have spread a lot of propaganda regarding them. They electronically neuter the settings in the drive so that a complete stall or some number of inches for some number of seconds are the alarm settings. So you could lose position by an inch and cut for 30 minutes and not gain position back until a retract was programmed.

FYI: Those same companies that use verbiage like your linked page for the DIY crowd, market the same motors and drives to mfgr's by saying closed loop allows them to use smaller, cheaper motors, (for a number of reasons) and reduce costs. In other words they tell the story to each that they want to hear.

[Bill George]

Properly designed and installed a stepper motor system is fine, there are thousands of older milling machines that had stepper motor CNC and worked fine. Even today they are used on a lot of routers, laser engravers and 3D printers, you name it. Servos with encoders are better and faster, but unless your running production do you need that speed?

I had a servo driven router before I had the one I just purchased and it was a pain in the butt. Most of the problem it was due to the people who designed and programmed the driver board and the software.

PS Just read Gary's post and that was the issue with servo system I had. it would fault out all the time not due to a overload but the set up in the software. BUT the end user, me and a few others got blamed for everything under the sun!!

[Gary Campbell]

Bill makes a good point. Even tho its related to load, the drives alarm setting uses an "encoder count error" to trigger an alarm event. Which triggers an output on the drive. Which triggers an input on the control system. The control system reacts in the manner that it has been programmed to. Take Bill's example above, the error count trigger was most likely set too low. Left alone most folks would set them in that manner. With the same result: a useless machine.

1000 encoder counts per rev is pretty common on steppers. I will use the example of my Acorn project. 1000 encoder counts, set to 250 as the alarm threshold. On a 5mm pitch ballscrew which advances 5mm or .197" per rev the error is set at .197 / 4 = .049". Yup, ~50 thousandths. Set it any less than that and the drive will alarm out under acceleration. Depending on the motor torque and acceleration setting the actual position will often be 20, 30, 40 counts behind the commanded position and the same amount ahead during decel. And that is OK. Here's why:

The drives will apply 100% of available torque once a loss of one native step is detected. Most of these motors have 200 native steps per rev. That's 5 encoder counts. so at 5 encoder counts drive power (amps) is increased until the count matches again. If you set it right, it's like cruise control on your car. Set at 60, come to an uphill section of road it presses on the gas, go down one it lets off. You wouldn't set the cruise to shut the car off if you were off by 1 or 2 mph would you? Besides, most of the time a non encoder equipped stepper looses position to the point where we hear the "ratchet" or slipping sound we have usually lost 3-400 steps or more. A 1/4 inch, an eighth at least. On the Acorn project using a step resolution of >8000 steps per inch and NEMA34 650 ozin steppers the acceleration can be set much higher in this case. Acceleration of 0 to 300 ipm (rapids) in .3 seconds. That's 1000 ipm/sec acceleration. Virtually unachievable with a NEMA23 stepper motor. So even if the bit hit a knot and got behind 249 counts, it would normally be back on position in a quarter second or alarm out.

What you need to remember is that all these awesome features and the extra components and programming cost real money. When the mfgr offers them as an option, most customers buy the lower priced options. When they are standard, customers buy lower priced models. One major mfgr that offers both sells 10 to 1 open loop systems to closed. The consumer CNC market is 100% price, not feature driven. And they publish the specs consumers want. That's the way new CNC buyers want it. That's why I build for experienced users that know what they want and why. They don't run like the consumer grades, for the most part I try to eliminate the keyboard and mouse. And I wont sell a custom machine unless the purchaser agrees to a full day of training. My shop or his. Both cost real money. All the good stuff does.

[todd werner]

I got the sense there was some marketing spin on that page, but even so, it sounds like a we'll set up closed loop with an alarm would potentially pause if a knot causes slipping, before the program ruins a job? Would such a system potentially let me re-zero and adjust my feed rate before the piece is ruined?

A lot of what I plan to work on will be a multi-step project that I'll have hours and hours invested in. It might be worth it having a safety on those jobs where I won't lose a sheet of plywood, but will lose a 9 piece glued up neck blank with carbon fiber reinforcements. Because I know I'll be annoyed enough when I destroy my plywood.

I do realize that it's far more likely a project will be destroyed because of user error on my part, and I'll make every effort to minimize that occurrence too. My nature is usually to go with the option that has the highest safety margins.

And if the closed loop is not an option for me, will the other two options also impact this concern?

At the same RPM setting, will the 1.7kw be less likely to get slowed down by an irregularity and therefore be less likely to meet with resistance that causes slipping? That seems intuitive, but I'm learning not to assume anything here.

And what's not as intuitive is whether a slightly stronger stepper with more torque will not slip when it meets resistance. That seems to require I understand both the torque and power curves. Still, if the higher torque motor has more torque and power at any RPM, will that also decrease the risk of slipping if everything else is held the same, and are there more powerful motors in both the NEMA 23 and 34 sizes?

Edit : Gary, you answered that last post before I could enter mine. I'm typing on a cell phone so I'm slow. It sounds like the question I posted on closed Loops isn't accounting for everything the loop does, since it sounds like a closed loop system will actually try to increase the torque to make up lost ground. Since an open loop won't even know it's lost ground when it in encountered a section of increased resistance, that means that as soon as it slips a little bit, the rest of the job is off by that much, doesn't it?

[Gary Campbell]

Would such a system potentially let me re-zero and adjust my feed rate before the piece is ruined?
Depends on if the error went into or was outside the part


At the same RPM setting, will the 1.7kv be less likely to get slowed down by an irregularity and therefore be less likely to meet with resistance that causes slipping?
Possibly

And what's not as intuitive is whether a slightly stronger stepper with more torque will not slip when it meets resistance.
Of course it will. But that's not saying it may ever be enough, if you are smart, it can be. The OEM's are not dunces, they put out matched systems that perform pretty equally in each price class. Users overdrive them.


Since an open loop won't even know it's lost ground when it in encountered a section of increased resistance, that means that as soon as it slips a little bit, the rest of the job is off by that much, doesn't it?
Absolutely

[Gary Campbell]

Todd...
Read your PM

[Brad Shipton]

Your closing of the loop is largely a check. Servo is told to move, moves, and while doing so it is constantly sending a message back of the counts to know it has done (or is doing) what it was instructed to do. If it thinks it has or is moving incorrectly it corrects itself. That is done with software. It would have to measure the power demand to know something like extra stress caused by a knot. That is likely out there, but not in the entry level machine class. Closed loop steppers are similar, just not as many counts per rev.

The force applied to the cutter is not that much larger at a knot. The problem with losing steps tends more to be when you have operations with lots of rapid stops and starts where the power demand is fluctuating constantly. If you really want to go sideways with the stepper discussion you can look at the reality of microstepping. I cannot speak to that very well, but Gary has before in the ultimate desktop discussion.

If you are concerned about cost, this will all be sorted out soon enough when you talk to the suppliers. Steppers for this machine cost a few $100 each, servos are $600 - $1500 each for a reputable brand (that is not Fanuc or Fagor because those are more). The cables cost a bunch more too. On my project one supplier quoted $2k for cables. Yes, just wires for four servos. WinCNC will only close the loop at the amplifier, and if you want it in the software (referred to as true closed loop by some) you will need a different controller. That will really ramp up the cost. Go look at what others are doing with the two machines you are looking at. Is that what you want to do? There are tons of people making guitar parts on entry level machines. Is that someone like Fender (assumed you are interested in guitars with neck reference), no, but they have money to spend. Are you going to be measuring things relentlessly after they are cut and would you be annoyed by cut errors in excess of 0.02" or so? If you are the measuring type, you might need to increase your budget. I am the measuring type, so I know that problem. If you are the measuring type I would be talking to Gary about one of his. These type of questions are handled better by someone that can customize things to suit your needs. Product suppliers have a stricter limit on how far they can go to customize a machine. I suspect the limit of the discussion with the two you are talking to will be is steppers, or servos using WinCNC. Knowing multiple controllers is a big deal for a product supplier. Gary has vast knowledge gained over years of taking things apart. There are others too that do this, but the majority of them are working on steel milling machines.

By the way, spindle power is kilowatts, not kilovolts. kW, not kV. Hp works too, but you need to convert using google.

[Jim Becker]

The really scary thing here is that I kinda understood all of that... :) :D :eek:

[todd werner]

Thank you. It sounds like with attention to detail, I could probably plan tool paths to minimize the risk that a slip related position error will go into a job as long as it stops the job after it happens. I think with a little more research I'll be able to at least know what to ask and to see if a closed loop system is worth the upcharge, or if the other options are.

May I ask what the increase cost of going with the closed loop was on your acorn project? I know it won't mean I can expect similar cost quotes from Camaster or ShopSabre, but I'm curious as to the current cost difference to a small builder/DIY person.

[Gary Campbell]

It sounds like with attention to detail, I could probably plan tool paths to minimize the risk that a slip related position error will go into a job as long as it stops the job after it happens.
That will be, as a CNC operator, your main task. No matter what machine you purchase



I think with a little more research I'll be able to at least know what to ask and to see if a closed loop system is worth the upcharge, or if the other options are.
I don't think either of those 2 mfgr's offer a closed loop option. I do know that the closed loop drives that I use would not fit into that size control box.



May I ask what the increase cost of going with the closed loop was on your acorn project?
You may ask, I will not answer. The number would not be applicable. My costs include parts, machining, wiring, relays and programming related to a different control system that are all part of my standard system. I don't produce machines that are not equipped with higher end closed loop stepper or servo systems. What is or is not included in a custom system that I build a half dozen a year of is totally unrelated to mass produced entry level machines offered by OEM's. In most cases the options you seek are only offered on larger frame model lines.

[todd werner]

Thanks Brad. KW not KV. :o
Maybe too much time sorting out tube amp components this week while cleaning up the shop.

[richard newman]

Todd, I have just a little bit of cnc experience, with a 20 yr old tiny (12" x 10") Technno Davinci machine. I had to replace the drivers and switch to Mach 3, which was an interesting learning experience, but luckily something you won't have to do! I'm a semi-retired studio furniture and banjo maker, just doing banjos right now. So far I've been able to cut and inlay mother of pearl in ebony with astounding accuracy. Also scratch lines to guide my hand engraving. Have cut fret slots, and profiled my fingerboards, again with great accuracy. Next will come some full 3d stuff.

The real challenge is mastering the software, in my case Adobe Illustrator for drawing, and Fusion 360 for CAD & CAM. This is where all the mistakes take place, and where the learning curve is really steep at first. Just about any machine would have done the work, the Techno happens to be heavily built for its size and accurate, but the cutting forces for inlay & slotting are minute, limited by what the micro endmills can handle.

When I have the funds, I'd like to upgrade to a larger machine which would still fit into a much smaller shop, for when I downsize from my big commercial space, and 2' x 3' seems just right. I understand wanting to fully understand what makes cnc tick, and what the absolutely perfect, yet affordable, machine would be, that's why I'm watching all these threads and videos. But I think but it's really pretty hopeless, until you actually have enuf hands on experience to relate the theories and myths to real life experience.

I think any of the machines you're considering would be great for hobby wood and aluminum work, they appear to be smaller size versions of genuine commercial machines, a market niche that has not been very well served. They look well engineered and constructed, by reputable and experienced manufacturers. Certainly more than adequate for hobby use.

I do think a spindle is a worthwhile option. You should expect much lower run-out with it, which is essential if you use tiny endmills for inlay and slotting. i had to regrind the taper in my machine's Kress router to get from .003 to .0001 run-out, which enabled me to use .015" mills.

"Buy your second machine first" sounds great, but I'd just pick one of those machines and start making chips. If you need to upgrade later you can easily sell yours, and have the joy of getting a new machine again. That "paralysis by analysis" stuff is real!

[todd werner]

Thanks Richard. Where are you located. If you're nearby it'd be cool to see the banjos you make, even though I don't play.

On the machines, I spoke to both companies again. They answered my questions, and for the most part avoided spin or hyperbole. I know I’m at the bottom of a steep learning curve, but I’m comfortable that both machines are well thought out and will be able to do 99% of what I want to try on them. The limiting reagent for the next couple of years is going to be my computer skills!

You guys were right, whether one offers any benefits over their competitor’s machine probably depends on the user. For anyone who searches on these and finds this thread, what I learned, and what you should confirm if you are looking at these 2, is:

Both companies machine the gantry faces flat.
Both use similar bearings, VFDs, and spindles.
Both use WinCNC.
Both have enough Z travel to let them lower their spindles to the deck. For the Stinger, that is true with or without the 2” gantry lift.
The Stinger has NEMA 23's on all axis, and the ShopSabre has 2 23’s and a 34 on the Z. I don’t know the final gear ratios or torque curves. I only know the Oz/Inch rating of what they would put on the machine if I ordered today.
The CAMaster offers an air counterbalance, the Shop Sabre has a bigger Z motor.

Sizes are:
CAMaster Stinger 1 SR23 : 25"x36"x5” or 7” with 9” Z travel
ShopSabre 23 : 30"x40"x5” with 6 ½” Z travel

Don't laugh too hard, given all my questions were about those machines, but one day after I decided to get the SR-23, I measured my space again, moved my 1200lb assembly table 10" to the left, 8" over, and ordered to the CAMaster SR-24.

[Jim Becker]

Don't laugh too hard, given all my questions were about those machines, but one day after I decided to get the SR-23, I measured my space again, moved my 1200lb assembly table 10" to the left, 8" over, and ordered to the CAMaster SR-24.

ROFLOL....similar happened to me, but I started with the SR-24, moved to the SR-34 Stinger II and ended up ordering the SR-44. :) :D Congrats on your order...and may the next two months go quickly for you.

BTW...one piece of unsolicited advice: Do the two day training! I just had the pleasure end of last week and it was outstanding. Gary is a gifted instructor, presenter and occasionally comedian. The factory tour was (very yellow) icing on the cake.

[todd werner]

Hi Jim,
I don't know when they're doing that training again and usually life is pretty hectic, but I'll look into it.
I am going to sign up for a CNC course at our local technical college this fall. They offer courses one or two days a week each semester. No intro courses over the summer though.
I've got several hours of video to watch on Fusion 360, and I'll find some Vectric videos too. None of that is Stinger/WinCNC specific, or VCarve specific, but hopefully my son and I will be able to figure this out.

[Jim Becker]

The Vectric video based training is pretty good use of your time. Watching project videos by makers is also "enlightening"; sometimes you get an "oh wow" moment and sometimes you get a "what was that dude/dudette thinking" moment. :D The two-day training events seem to happen about every two months. Keep your eye on the "News" section of the manufacturer's web site. The $350 cost is reasonable; you can drive there from where you live (I drove from PA...) and the Microtel hotel nearby is also relatively inexpensive at about $60 per. Any training you do is worthwhile because the biggest part of getting going with CNC is the learning curve which is largely centered on the software side of things. That's not to say there are not other things to learn relative to "speeds and feeds", etc., but getting comfortable with the software angle is really important, regardless of machine brand or size.

[Jerome Stanek]

Hi Jim,
I don't know when they're doing that training again and usually life is pretty hectic, but I'll look into it.
I am going to sign up for a CNC course at our local technical college this fall. They offer courses one or two days a week each semester. No intro courses over the summer though.
I've got several hours of video to watch on Fusion 360, and I'll find some Vectric videos too. None of that is Stinger/WinCNC specific, or VCarve specific, but hopefully my son and I will be able to figure this out.

You could also go to the Shopbot page and see what vectric training they have on line. The training is not Shobot specific and TJ does a pretty good job.

[Jim Becker]

https://www.youtube.com/user/Vectric/playlists

Huge number of training videos directly from the horse's mouth... :)

[todd werner]

Shopbot is only 20 minutes away from my home, and I could have gotten a great deal on their Desktop Max from someone 2 hours away that used it for 10 hours and then upsized. I almost feel disloyal for not buying from ShopBot, but the Camaster and ShopSabre overhang will let me work on the ends of a guitar neck if I want to, without pulling the aluminum t-rail deck off the Shopbot.

That Desktop Max with a 1hp spindle and a 6" rotary indexer, plus several bits, less than a couple of months old, is still on CL for a 9k ask. That's about 25% off. They might take less, but they didn't write me back when asked if they'd consider 8.

[Jim Becker]

One of the folks I met in training last week plans to use his Stinger for guitar work including necks.

[todd werner]

Just one participant?

That must have been a small class, because statistics show:

95% of men in the U.S. own a guitar
96% of them want to make a guitar
97% think they can make a better guitar than they can buy
98% of them can't play the guitar they own

and 99% of all statistics are made up on the spot ;)

[Gary Campbell]

Todd...
Check your statistics. Mine say that 86.7% are made up on the spot

[todd werner]

That does sound more accurate Gary

[Gary Campbell]

Well played! :)

[todd werner]

Gary
With a "desktop" machine like this, is there any advantage to leaving assess to the underside through the middle of the table I'm building for it?

[Gary Campbell]

Todd...
You will want to check, adjust or lube the drive components on a regular schedule. I set one end up on a couple blocks of wood to do my table tops.

[james mcgrew]

Dang this was a good read !! See you guys in April !! Shopbot, CAMaster, Axiom and hopefully one more will be bringing machines !

[Art Mann]

Hey Todd,
I have cut a lot of wood and plastic on my Stinger I in the last 3 years as a hobbyist and my spindle is just a Porter Cable router. From my experience, all your concerns about accuracy and skipping steps on a stepper machine are wasted. My two regrets are that I didn't buy a real spindle and the cutting envelope is too small. If you buy a good machine like you are contmplating, you should be much more concerned with mastering the software and learning the stuff only experience can teach. I didn't do a class early on but probably should have. This is coming from someone who spent much of my career designing digital controls for manufacturing machines.

[todd werner]

Hi Art,

Thanks for the input. It's quite possible my concerns on losing steps are silly, but my son wants to be able to cut aluminum, and there seemed to be no harm in looking for a little extra torque. I actually spoke to Camaster, and they are going to build my Stinger 1 with 500 oz motors on all the axis. I am paying for that, but they were certain the rigidity of the machine is sufficient, and their engineer didn't see any downside other than the cost. They will have to re-engineer a couple of mounting plates for the slightly larger motors, but I suspect that since I'm doing it and that work will be easier after mine is , they may make 500 oz motors an option moving forward.

On the size issue, I actually considered the used Stinger 2 that just got listed, but there's no way I can get it down the stairs and through the door to my basement. Besides, for what I'll be doing, it's not necessary. Fretboard inlays, guitar parts, maybe some small 1/4" or so thick aluminum parts, foam, and end milling on 2-3 foot long boards for joinery. The longest pieces I see myself cutting will be 36 to 38" long, so I think I'm ok with 24x48". I have no desire to make big cabinets or work with sheet materials. It's just a hobby tool for me, not something for a business.

I have ordered a 1/8" collet already, and several end mills. Some flat/fishtail end in right and left spiral, some ball end, some tiny diamond burr left spiral for inlays, a 1/4" Whiteside V-grooving bit. I've only ordered up to 3/8" bits other than the spoil board bit. I'm also watching some Fusion 360 videos and planning to start the table and dust collection plumbing. Possibly the most important thing is that I will take a class on CNC at our local technical college this fall, and possibly the subsequent courses as well.

[Bruce Page]

I have ordered a 1/8" collet already, and several end mills. Some flat/fishtail end in right and left spiral, some ball end, some tiny diamond burr left spiral for inlays, a 1/4" Whiteside V-grooving bit. I've only ordered up to 3/8" bits other than the spoil board bit.

That's a good start. :);)

[richard newman]

Todd, i my experience it's not necessary to use down cut spiral tools for inlay. I've had excellent results with regular 2 or 4 flute micro mills, from .015 up 1/8", in ebony and other nasty, brittle woods. The rigidity and controlled feed make routing a whole new game. For the tiny bits runout is critical, at least according to the experts. If you haven't already discovered them, PreciseBits has tons of information and great products. https://www.precisebits.com/

[todd werner]

Nicely organized Bruce.

Richard, I got the diamond Burr left spirals for ablam or abalone, not for the fretboard or soundboard. They were only a few bucks each. What do you mean that the run-out is important? On the bit or on the spindle/collet?

[Gary Campbell]

Todd...
You use the term "right and left spiral" a number of times. Are you referring to upcut and downcut or to CW and CCW rotation?

[todd werner]

Up cut and down cut if the spindle only turns one way.

[richard newman]

Nicely organized Bruce.

Richard, I got the diamond Burr left spirals for ablam or abalone, not for the fretboard or soundboard. They were only a few bucks each. What do you mean that the run-out is important? On the bit or on the spindle/collet?

Run-out of the bit is what counts, but it all comes from the accuracy of spindle taper and the the collet. I would talk to Camaster and make sure they know you're going to use micro bits and need a spindle with minimal run-out. Maybe they'd be willing to indicate a few of them and give you the best one.

When you get the machine, put a bit in and indicate on the shank with a good test indicator. You can rotate the collet in the taper til you find the best matchup, and then mark it. If you're lucky what ever errors are present will cancel each other out and you'll have perfection. That's the way my marriage works... so far.

[todd werner]

Richard,
The idea of rotating the collet to try and oppose the run-outs is fantastic advice. Thanks.

[Bruce Page]

Richard,
The idea of rotating the collet to try and oppose the run-outs is fantastic advice. Thanks.
If you buy quality collets (precisebits.com) and not cheap knock offs you should be fine. You can find imports at 1/3 the price but there’s a reason for that. I always buy precision grade and check them with a precision ground pin and a tenth indicator. I haven’t found one with a TIR worse than .0005 with most better than that. Remember, collets are a consumable and will wear out with use, they must be cleaned/blown out with each tool change and must be snapped into the collet nut firmly.
I checked my spindle runout when my machine was first set up and it barely moved the needle.

[Jim Becker]

It's also extremely important to clean the collet each and every time it's used and the bit is removed...but that should go without saying. I agree with Bruce that this is one place to ALWAYS buy quality. So when it's time to replace what comes with your machine or to add other sizes...invest in good ones, even though collets are technically a "disposable" wear item.

[todd werner]

I only ordered a Techniks 1/8" since Camaster is providing 1/4, 3/8, and 1/2.
Going to have to make a bit/collet holder soon.

[James Biddle]

I also kept a few collet nuts on hand with the collets snapped in for a job to make the FTC change easier and faster. Be very careful when switching out collets that they are fully snapped in before installing them. If you bung up the threads or taper on a lower hp spindle too much, the fix is to replace the spindle, not send it in for repair. The few times I've had a crash, I tossed the cutter and collet. To me, that's part of the 'consumable' part.

[todd werner]

So there are Shars ball bearing collet nuts on ebay that are less $ than the Techniks mini ER25 nuts. Is there something special about a ball bearing collet nut? If I should have 2 of these things, I want to buy the right one.

[Bruce Page]

I ran the OEM nut the first 2 years and switched to this: https://www.maritool.com/product_info.php?products_id=47
Not too expensive and works great.

[todd werner]

What makes that one better than the OEM?

[Bruce Page]

There’s nothing wrong with the OEM nut. It’s a little difficult to explain but I like the maritool nut in that it does not immediately release the bit when you loosen the nut, it holds the bit until you turn the nut another ~ ¼ turn. That last ¼ turn can be done by gripping the nut, it does not require a wrench on the nut (usually) so it is easy to drop the bit into your hand as you loosen the nut. Hope that makes some sense.. :confused::rolleyes:

[Gary Campbell]

I have found that the ball bearing collet nuts often have balance issues when used on high rpm spindles.

[todd werner]

Makes perfect sense Bruce. I've dropped enough bits from the drill press to see how that could be helpful.

Gary, I'm going to assume you are implying the HSD spindle is a high speed spindle.

[Gary Campbell]

Depending on model, 18-24,000 rpm.