New CNC build - AVID 4848Pro with GCnC Electronics

[Prashun Patel]

Thanks, Gary. That's valuable information.

[Bill George]

Ditto Gary, very nice to know. I hope your enjoying retirement. We need fish pictures!

[Will Blick]

Ben, mucho appreciated u taking the time to share here.
I know I will be in the same boat hopefully in the NOT too distant future.
a few questions, for anyone...

1) is the vac system the ultimate hold down for CNC system? what is price range?

2) The composite nailer seems like a good system, what was the budget issue? how costly is a composite nailer?

3) Can u run two Gantries on one system, one spindle working the 4th axis only, the other doing standard CNC operations? of course, u would buy an over sized table with the 4th axis dedicated to one end.

4) Was there a close contender to Avid in your buying decision?

5) If you do work that requires tool changes, it seems the ATC is a great investment, otherwise u need to be constantly there by the machine, defeating the purpose of letting the machine work for you... am I missing anything here? Are there issues with these that still force babysitting?

6) Noise abatement. I know routers scream... noise can be a bit of an issue at my shop, is there any off the shelf noise abatement products that absorb some % of the noise? I guess building around it and sound proofing the room would be the best solution, but that eats up a ton of space.

BTW, I love Jims comment about, buy your second CNC first... makes so much sense. These are quite the investment not only of your money, but your time...

[Ben Grefe]

Hey Will, some of these items I have researched, some I haven't.

First, onto a hold down system. Everybody I've talked to tells me that a vac system is the holy grail of hold down systems and I've seen DIY designs that use multiple $50 shop vacs all the way to large turbines (Hurricane Black Box seem to be a popular one) for 2-3k. I bet I'll add a vac hold down system eventually, but I just want to use the machine for now. Screws and clamps really aren't that bad, especially with secondary spoil boards that are easily replaceable.

I thought about composite nails, but brass screws seem almost as safe to the machine but cheaper and simpler so that's my plan for hold downs that I need to put in dangerous places. I'm going to experiment with double sided tape and sacrificial spoil boards as well.

I've never seen a machine with 2 gantries, but knowing what I know now, I don't see why you couldn't do this. Because you'd need a full electronics package for each gantry it's almost like you'd make 2 separate CNC's out of the same physical CNC machine. Be aware that the gantry+electronics+spindle is easily 70% of the cost of the CNC in my setup, so you're talking about quite the cost increase. Also know that you'll lose some table space with that idea because the gantry 'overlaps' the table a bit. It's a cool idea and totally doable though.

The next closest new contender was a Camaster machine. Although I never checked out a machine, I watched the used market for at least a year and if anything in my size/price range popped up then I would have seriously considered it. I'm talking any brand as long as I could have tried it out first. Frankly the frame is pretty simple, like a jointer. It's the electronics/rails/spindle/control software that really swings the machine from terrible to great. Even an old used machine with a full brain retrofit would have been under consideration, but nothing popped up locally (PWN).

I will say, my fav part of the Avid is that I think I've bought my 1st and 2nd CNC's at the same time. Unless I run into rigidity problems I'm pretty sure I'll have no problem adding 5 feet to the system to get me 1 foot for an ATC and then the ability to do 4x8 sheets or add an A axis of some sorts. I'm more interested in doing vertical joinery so I also like that I can move the table/legs around to make a nice vertical table. Not all other CNC's al

I'd love to add an ATC eventually. Even as a '1 time hobbyist' (aka new designs all the time, few repeats aside from doing test cuts), I'm already doing a lot of bit changes. I have no idea how hard or easy it is to CAM the tool changes in fusion360 so you'd need to consider that, especially if doing 1 off designs all the time. I will say, I've seen a few warning videos of CNC's going rogue. Work popping up from the spoil board or openloop steppers losing steps and running into clamps. This can result in a fire. From what I understand you shouldn't leave the CNC without a babysitter who can respond immediately in case of emergency.

Looking at ATC options, I do see that CNCdepot has one for ~2500 more than the Avid spindle. No idea how much control logic you need to add ontop (think pneumatic relays and different cooling). I'm hoping by the time I'm ready to add a ATC there will be other options on the market to consider.

So far my dust collector is louder than the CNC itself. The best noise containment that I can see is building a full box around the CNC that you can remove to secure material to the spoil board and do system maintenance.

[Will Blick]

Thx for your thorough response Ben, very helpful. A few follow up questions if you could be so kind.

1) When u say your dust collector is louder than your CNC, I assume u mean with spindle running but NOT cutting wood? How do you compare the noise to a 3HP router cutting dados?

2) What caught my eye also about the AVID was the videos on YouTube doing joinery work with a vertical table. I find this feature and the 4th axis option, taking CNC to the next level for fine ww's. I know there is other CNC's that offer 4th axis, but is there CNC's that offer a table that can be so easily modified to create the vertical edge for edge joinery? The new software for joinery is just brilliant.

3) You mentioned something interesting about repetitive work pieces. This is where I saw the benefits of CNC. OTOH, I have been dragged down many endeavors in work and in life, that seem to provide tremendous added efficiency, but in the end, the efficiency was often NOT realized due to all the nitty gritty details often overlooked. With CNC, you have the CAD time, CAM time with constant learning curve with updates, etc, experimenting with tool cutting speeds, bit sizes, cut paths, work holding, etc. I can see how all the variables really need to be refined before you achieve the holy Grail of PRESS START and the machine produces your perfect parts. From what I have read, its not as plug n play as it appears - this is evident from youtube videos showing many iterations before the part is produced as desired, i.e. it is not always easy to dial in all the variables. Maybe others who have used CNC for a long time can comment on this...i.e. if you want to make 20 of something, I assume that is considered ultra low volume and there is often minimal or NO time savings to CNC vs. conventional ww machines. But obviously not true if you were making a 1000 of the same part. I realize there is many variables here, but I have always struggled getting my head around when the CNC really starts yielding the benefits most people buy it for.
This assumes you are not using CNC as a part time hobby, fascination, challenge, etc. Instead, a small shop trying to make and sell items the CNC delivers.

Some comments on your post... it seems you are buying your 2nd CNC machine first, congrats, I am sure u will be glad in the end. Love the brass screw idea for hold downs!! Interesting comment about the ATC. IF you need to be near the machine and paying attention to the cuts, I guess changing the cutters is not a big deal. I envisioned walking away from the machine and doing something else and not hearing or seeing the CNC at work.

Fully understood about the two gantry's. This was something I would consider preparing for, at purchase, i.e. buy the ideal size table the first time. I thought running 4th axis at one end, and a vertical table for joinery at the other end would nudge me to buy a larger table length up front. Agreed the cost is in the Gantry's, but it sure would save a lot of footprint vs. two CNC's. It is a great option the modular Avid allows.

With the Shaper Origin, the decision to buy a fine ww CNC becomes more complicated. It seems SO has really allowed ww's to do most of the tasks of a table CNC without the footprint... In addition, the work piece size is almost unlimited. A lot comes down to volume of work and space. I would be interested in hearing if others also are on the fence regarding table CNC vs. SO.

[Jim Becker]

Will, relative to number one, a spindle cutting is still noticeably less noisy than a big old router motor cutting the same material with the same tooling. It's true that there is real noise from the tooling when using a spindle, although that's material and cutter dependent. A .25" or .375" spiral tool cutting hardwood is pretty noisy, but all of the noise is from the tool, unlike with the universal motor of the router. A .125" cutter is relatively quiet on the spindle, even in hardwood. A v-bit is very quiet. Cutting something like MDU or Corian...the operation is nearly "conversationally quiet". The outboard systems such as dust collection and blowers for a vacuum table certainly make noise, but where they live matters. My DC is in a sound reduced closet with an indirect return to my shop. I have acoustic tile on the ceiling. When my cyclone is running it's a "rumble in the background" plus some noise from air movement.

[Will Blick]

Most of the CNC's I have been around, seemed as loud as my large router when cutting. I guess the fact the spindle makes less noise than the router while not cutting, the total net noise is less....
How effective are those acoustic tiles? Brand?

[ChrisA Edwards]

Will, I own a Shaper Origin. It produces good results, but it is very slow and time consuming.

Although they advertise the ability to work on pieces that are not restricted by size, and show this with guys cutting patterns in hardwood floors, at 64 years young, I could not imagine spending about 4-6 hours, down on my knees, pushing the SO in the necessary direction.

This holds a little true when working on a project on a bench, once your design starts getting a little bigger than your comfortable arm reach, shuffling a 15lb tool around can get pretty tiring. And although the SO has correction to compensate the operator movement, it's still possible to crash the bit and cause a defect before the SO can retreat the bit.

I've been following this thread with interest as I'm looking at a 5' x 5' versions of Ben's setup and have already got a quote from AVID and spoken to Matt about the electronics and spindle.

Not to steal away from Ben's thread, I made about 5 of these Bread Cutting boards 13" x 8", using my SO with a 1/4" bit. Grooves cut to 1/4" deep. Each board took about 90 minutes.

[Will Blick]

Chris, thx for the feedback on the SO. I would never crawl on my knees
they were not designed for that, specially at our age!!
valid point about the reaching.... of course the appeal of the Avid is, let the gantry do the heavy work. Seems many of us really see the Avids value.

The SO really seemed appealing for joinery. Their videos show impressive double dovetails that look spot on. But my guess is, when u span over 24" distances, it must get hard for the system to maintain tight tolerances which is required in joinery. When I saw the Avid do joinery on YT, I immediately re thought my strategy. I have a habit of jumping into things too fast, and this is one investment I want to be extra careful about, plus I have time while I build out shop space.

On the subject of joinery and fine ww with CNC. Can a machine like the Avid chamfer the edges of a board? I would think this is NOT an easy task, unless the CNC is equipped with a scanner to know exactly where the boards edges are. I realize you set the board in place and advise the CNC of its location, but if the board is 5ft long, I would think the chamfer would not be the same depth the entire run? I am not suggesting that a CNC is the ideal tool to perform this task, as a handheld router or router table with a chamfer bit w/ bearing is perfectly designed for this task. I use this example as a means to understand what is possible with CNC, and what is impractical.

Chris, I just saw the added bread boards pix and comments...
first, they are beautiful, well done, nice project...
second...ummm, 90 minutes each? damn, u never hear real world information like that... I would have guessed 20 minutes each! thx for including those kinds of details, Avid looking better and better

[Wes Grass]

Two gantries would be fine, with 2 separate control systems, as long as you're really careful about travel limits so they can't crash into each other. There are commercial machines that are capable of this with one control running 2 programs simultaneously, but I highly doubt any of the PC based systems could manage it without a ton of custom code. Here's one place I'd love to be wrong.

As for a 4th axis, depending on what programming system you're using you might not be able to generate anything other than X, Z, and A output. Which means the gantry can be fixed on CL of the 4th axis, saving a drive system (or 2) and the associated linear guides. But you're still in for another control if you need simultaneous operation.

A tool changer adds more than multiple tools, it also gives you preset offsets which makes for fewer mistakes in setup. Any decent CAM system will handle tool changes and the associated offsets. I used it with V-Carve and M3 to fake multiple 3d roughing passes using a finishing command and telling it the cutter sizes were changing and ignore tool change in the control.

I've got an idea for a multi axis system, something along the lines of a poor man's 5 axis, by reorienting the spindle and mapping the axis drives to be able to machine 5 sides. I thought maybe multiple configurations would work, just restart the system with whichever config file maps things the way you want it. What little I've looked at seems to require manually remapping the axis' to the proper motors, travel limits, etc. Which is fine, except ... at least in the case of Centroid ( I haven't found anything re M4), cutter radius comp only works on the first 2 channels and tool length offset only works on the 3rd. And I consider those mandatory. So I'd either have to pull plugs on the motors, or wire some massive multi-contact rotary switch to accomplish it.

In reality, I'd probably only use 1 of the extra config's anyway, and probably only once or twice just because I could. A 4th would be more useful. And even then, I think I could get by with manually indexing it and running another program. And I'd have no need I can think of to be running it while something else is going on at the other end of the table. And my VMC already has a 4th on it, but a router would be so much easier to clean up afterwards. I've taped newspaper in, and vacuumed until the cows come home, and the next time it gets run with coolant there's a layer of sludge in the tank to shovel out.

[Jim Becker]

M
How effective are those acoustic tiles? Brand?

Just inexpensive Armstrong acoustic ceiling tile, designed for drop ceilings, but stapled up after I insulated. When you walk in my shop from outside, you can "hear" the silence and lack of sound reflection.

[Gary Campbell]

"Two gantries would be fine, with 2 separate control systems, as long as you're really careful about travel limits so they can't crash into each other. There are commercial machines that are capable of this with one control running 2 programs simultaneously, but I highly doubt any of the PC based systems could manage it without a ton of custom code. Here's one place I'd love to be wrong."

I have been a part of a few special purpose machines that, for the most part, do most of what is mentioned above, but not likely all. "Imagine, if you will, a machine built in a world where......"

A gantry with dual independent X Z heads fed by 2 outboard rotary tool carousels. Using the same code, lets say to cut electric guitar bodies, an operator could cut 2 lefts, 2 rights or a left and a right.

A second X Z head connected with a spherical tie rod link that works as a copy cat. Cuts 2 for 1

Twin Rotary axes that have driven chucks on both ends cutting custom shotgun stocks

And to be more on point, A customer with a large SB frame that commercially cuts acrylic from 32 by 48 blanks. He added another gantry and controller and runs one from each end. 2 gantrys, 2 controllers. connected only by a common input configured as a collision alarm. His videos were better commercials for my controllers than I could have imagined as they both cut the exact same file over and over, all day long.

So to finish the Rod Serling reference: "Imagination...its limits are only of the mind itself"

As it applies to CNC machines: "Nothing will hold you back except your imagination....... and of course, checkbook" ~GC

[Jim Becker]

Gary, I saw a video a while back of a multiple head/spindle unit that was doing guitar necks in a factory, maybe 4-6 at a time; I don't recall. It was a mirrored movement setup and fun to watch for sure.

[Wes Grass]

A few years back when I was doing deep molds with steep, even vertical, sides, I thought about a 3-1/2 axis where the spindle was mechanically tilted as the head ran across the gantry. Maybe to +-15 or 20°. The program would be written so it would comp both Y and Z for the change in tool position as it swiveled. Fairly simple Trig functions I think.

Here's another idea ...

Dust collection on a 5 axis is a problem. So the idea is to add a C axis to rotate the collection port around the tool using 3d cutter comp values to tell it where the surface is that's currently being cut, so the port is moved to the opposite side.

[Will Blick]

Wow, some serious experienced CNC users here... Impressive Wes.

I had my sales consult call with Avid today. A few highlights.

1) Avid is moving to 4HP spindle, introduced today, air cooled.
2) no issues with dual gantry's, common sense required.
3) Avid will be introducing their own ATC end of this year... nice to have one phone call to solve all issues.
4) Avid offers the vertical table at purchase, I was unaware of this. I thought it had to be homegrown.

Of course, the price really adds up fast when u keep adding bells n whistles.