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Don Corbeil
01-31-2014, 10:34 AM
Hello, first post here, after reading many on this forum for a few weeks :cool: Very happy to have found this forum with the knowledge contained in here.

So, I'm researching the purchase of my first (CO2) laser, and I wanted to run this question by you, to get an idea of what things you may have wished you had ordered with your first laser, but didn't. What features did you immediately realize you should have included in that initial system? Was it power, work area, support, job control software, pass through options, etc?
As I get closer to pulling the trigger on a first laser purchase, I see many variables that affect my choice, and that could easily bump the price up considerably. I'm curious as to what options others have found worth putting those extra dollars down right off, and being glad they did as they discover new applications or opportunities.
Thanks for any feedback!

Joe Hillmann
01-31-2014, 10:58 AM
A larger engraving area and more power.

Mike Lassiter
01-31-2014, 11:12 AM
What Joe said. We got the biggest ULS available and 60 watt cartridge. Later added second 75 watt cartridge. Couldn't get it all at first but able to cut considerably faster with extra power which is very nice. Being able to use large 24"x48" table has it's blessings snd curses. Larger material allows less waste at times but warping more of a problem.

Dave Bonde
01-31-2014, 11:13 AM
I will start by saying I have a small work area (think small 40 watt hobby laser). The #1 option I wish I had was more working depth followed by work area. For the work I do I almost never use 100% power.

Dave

Paul Phillips
01-31-2014, 11:18 AM
Hi Don, welcome to the Creek. I also searched the forums diligently for months before I purchased mine, one thing I heard repeated was "buy as much power as you can afford" so I followed that advice and got 120 watts and I can't imagine having less than that for the high production work I do, my feeling is that I could probably have gotten by with 60 watts but the extra power allows me to work at a faster pace and get more done in the same amount of time. Also, for me, I don't have time or the temperament to deal with fixing constant problems so the support that comes with my ULS has been invaluable, when you don't have time to do lots of troubleshooting and you need to be up and running ASAP when a problem does occur, being able to make a call, get an immediate diagnosis and parts overnighted and be up and running the next day is worth every penny to me.
My 2 cents, hope it helps. Let us know what you decide on getting.
Paul

David Somers
01-31-2014, 11:20 AM
Don,


I am in the same boat you are in. Been lurking here and pestering folks with questions for months as I try to decide if a laser is right for me and what I will end up with.


After much pondering I do think a laser is a good tool for me. Now it is a matter of what to get and how much to spend. I classify as a serious hobbiest who wants to use the laser as a secondary tool and for what it can do directly as well, so spending BIG bucks is out of the question. That has pretty much put the big 3 companies out of the running, as much as I like what they offer.


Mike Null did suggest I check out Rayjet so I am waiting for some word from them. Otherwise, I will likely end up with a Chinese machine imported through a company like Rabbit USA. I am not eager to deal directly with a Chinese import however.


Personally, I have always been of the mind that if I get something I am never dissapointed if I get more capacity than I thought I would need originally. So going larger on bed size and higher on power than I initially thought I would need appeals to me. In the Chinese lasers I lean heavily towards a RECI tube which puts me at 80watts or better. 80 is a good amount from what I can see.


A rotary seems like a good tool for me but for the things I want to do I would likely need to modify it some, so using the really expensive units from the Big 3 is less appealing. The rotaries from a company like Rabbit are less expensive and I won't feel badly if my uses fall out of the warrantee. I would certainly talk with the seller about what I want to do though.


Z height is important to me. The more the better. Oddly enough, the solid and well manufactured cases of the big 3 seem to limit my z height options unless I go into their really expensive models. But in the cases from someone like Rabbit there is a ton of unused space below the lowest official table height and I can see how to take advantage of that space to gain alot of z height. I don't see most laser engraver users wanting that kind of height though. Most of us are focused on varying thicknesses of flat stock and z heights in excess of 6 to 8 inches are not needed.


I might think about the materials you will cut and check out the forum for the table type folks are having the most luck with. Tables are expensive and it seems many have found they really didnt need a secondary table that they bought for what initially seemed like a good reason. And remember, depending on your needs, you may be able to make a table to do what you want. The laser seems to be a great tool for making up different types of work holds.


Air flow at the lasers cutting/engraving point seems to be a biggie. As is venting, and possibly filtering of exhaust gases. And fire extinquishers.


Various focal length lenses seem to be of much less importance than I thought they would be. Though in my case a long lense would be helpful for working in deep areas. Otherwise a good quality 2inch 55mm lens seems to be dandy for almost all uses?


And of course, there is the software you will use to design with, and the software used by the laser to take your graphics file and process it for the laser. I suspect those may be the biggest learning curves in the whole endeavor if you arent already familiar with a particular package.


Having babbled about all that, I am eager to hear what thoughts folks who actually have a laser express!!!


Good luck as you narrow down your decision!! Hope it ends up being a great choice for you!


Dave

Bert Kemp
01-31-2014, 11:39 AM
I think you have to ask yourself this question first. What are my intentions with the laser.
1. Will I be cutting more or engraving more?
2. What materials will I most likely be using.
3. How thick will my materials be and how large.
4. Am I in business or is this a hobby.

I think Get the largest bed size you can afford.
If your engraving more then cutting I would stay at 80 watts or below, but if your going to cut then go with what the $ says and get the most bang for the buck.
Are you going to do a lot of round objects, Pens, glass's ECT then you need a rotary but if not why get it.
Are you going to do thin material like paper or fabric then you might want a vacuum table, but if not then why get it.for an occasional thin item you can find other ways to hold it down.

So its really a matter of what you intend to do with it to really be able to decide what do I need and don't need. JMHO

Glen Monaghan
01-31-2014, 11:56 AM
Don,

This is a lot like saying you are researching your first car and wanting to know what other people wished they had done differently when they bought a car. The answer is highly dependent on what you (or they) have in mind with their purchase. Some people are buying as teenagers and just want cheap transport, some as new parents and seek safety and reliability, some as gear heads who want to customize/race/strut, and so forth. Some have the ability and interest in doing their own work on it, while others either don't have the ability or the desire and so will be more interested in having good post-sales support available. Some are okay with imported machines, some with used machines, and some only want brand new made-in-USA (or country of your choice). And some are buying for commercial reasons while others are for personal/hobby purposes, so their wants and needs are radically different.

Having said that, almost certainly most (but not all) laser owners would cite more power, and a large percentage would say bigger (and possibly deeper) table. Other options (rotaries, special tables, lenses, etc.) would likely be "long tail" items.

Having said that, just because most people cite more power as number one desire, that doesn't mean it's the right choice for you. Purchasing budget will drive everything, and just because someone else has been able to get their machine to pay for itself in X months doesn't mean you will, so stretching your wallet to the limit to pay for more power or size than you are sure you absolutely need could be a huge folly. Personally, I tend to run my Epilog at full power and regularly run jobs that would greatly benefit from more power, as well as don't do a few jobs that require a larger work space, and do run a few jobs that require work-arounds due to space limitations. So I fall into the "wish I had more power and a larger table" but am financially better off having bought less because I just had a very profitable year (up 10 fold over previous year), in part because I wasn't strapped with the extra capital expense of a much more expensive machine. Even though it has less power (and so is slower than I sometimes want), it still more than meets my overall needs. Same way I would really like to have a new Lamorghini Aventador LP 700-4 Roadster, but am basically satisfied with '94 Nissan 300Z. ;^)

Your mileage may vary, but other people's experiences won't be of much help unless you have the same goals, constraints, and circumstances as they had.

John Bion
01-31-2014, 12:32 PM
Hi Don,

1) I would buy from a reputable local seller rather than direct import from China. This ticks numerous relevant boxes.
2) I would have ordered an 80w for engraving instead of the 60w I did get - this would be more flexible for me.
3) I would have ordered a 130 or 150w instead of the 100w I got for vector cutting,
4) I would have had more bed-size on my larger wattage vector machine,
5) forget the frilly rubbish on Chinese machines; red dot pointers and auto focus - they just give grief and don’t work well,
6) Get a proper compressor (and a water/oil trap for it if necessary),
7) Are you sure this is the machine you need? Some of the things we thought that Lasers could do they either can’t or are not well suited to. This is just one more tool in your box.
8) Insisted that the actual bed size of the laser was the quoted size of the bed - I have a personal frustration with the honeycomb bed having an inch of aluminium bordering it all around to cause flash-back and resin burn, (Chinese machines) thereby reducing your real life working area.

Kind Regards, John

Keith Upton
01-31-2014, 12:58 PM
You'll have to tell us what you plan to do with the laser for us to really be able to help you.

My situation is a little different then most I think. I've been out sourcing laser work on my own products for a couple of years. It finally got to the point where I could buy my own laser for what I was paying to have it done each year. So, knowing I already had the "sales" to pay for the laser, my remaining limitations were how fast I could be up and running on my own and the space I had in the office for it.

That first one pretty much meant I was looking at the big 3 companies. I need to be able to get the machine within a few weeks and have it working right out of the box. Having near real time support if needed was a big part of it as well. I ended up going with Epilog because their factory is just 1.5 hours down the road from me. If anything happens to the laser, I can be up there the same day if need be.

The space requirement was the hardest thing for me to deal with. I knew I wanted a bigger working area and possibly the higher wattage those normally come with. But the reality was I only had room for a unit that would fit on my desk. This meant I had to go with their Mini 24 (12x24). It fits the decks perfectly and I was able to get the 60w which helps out on speed some.

I also bought the rotary attachment and their pin table. The rotary was just for "future" stuff (though I've already been able to create and sell an entirely new product because I have it). The pin table I only bought because of the need to be up and running as fast as possible. I had already thought about building my own, but that would take time which I did not have. As such I only bought one of them (they are 12x12).

If space was not an issue (which it is not so much for me anymore... go figure right), I would have gotten a bigger working area followed by more power. The working area can limit you to what you can physically laser. So with out the space, you are simply not going to be able to do some jobs. More power will just make you faster for the most part. With a few exceptions, a 30w will do the same thing a 60w can, it will just take longer. If you are all about doing production runs, than more power is a big bonus.

One thing to keep in mind about the initial purchase, there is quite a bit of room on the price to negotiate. I was able to get the rotary, 1.5 and 4 inch lenses and the pin table for just slightly more than what the base laser was listed for. When you do a big purchase, it's a lot easier to get them to give you more stuff for free ;)

Kev Williams
01-31-2014, 1:22 PM
I'll just say this-- 20-20 hindsight for us won't work one bit for you. You can't possibly know what "would work better" for YOU until you have and use one yourself. My first laser wasn't a 'hobby' adventure. I cut my engraving teeth on a Scripta pantograph in 1966 when I was 11 years old. I Joined my parents business full-time in 1976, we got our first computerized Concept 2000 in 1981. Several machines and 19 years later, I decided I'd better get a laser because every other phone call concerned laser engraving. My New Hermes rep had a 4 or so year old 'test drive' 25 watt Optima (built by Universal), 18x12 table- it did all their laser engraving and went to every trade show with him. It was well used when I got it in 2000. I'd never even seen a laser at work before, so it was all new to me. In my mind the thing was perfect, a whole new area of income opened up, along with lessening the engraving load of the other machines. I got our LS900 3 years later simply because I had more work than the Optima could keep up with. But I DID get more power and workspace, which has been handy! And I just bought the new Triumph - with more power and workspace- because again I have more laser work than lasers!

What would I have changed? Actually, nothing. Everything has it's shortcomings and compromises vs something else. Me, my strength is adapting to what I have. Just because a certain tool isn't necessarily designed to do a certain thing, doesn't mean it can't do it. You just need to experiment, and show the tool who's the boss... ;)

Don Corbeil
01-31-2014, 1:46 PM
Wow, thank you for the quick and informative replies... And for welcoming me to your forum :) Glad to be here!

Your responses bring up good questions for me. Really, the challenging part right now is choosing a niche(s), with what product, material or service I want to work with, and then choosing the best equipment for that use. My idea is to use this for a developing small business that would target architectural feature engraving. That is, I would be trying to target services/products that added value (by engraving) to specific exterior/interior architectural features in new construction and/or remodels - ie doors, windows, cabinets, fireplace mantles, engraving glass block, picture frames, lighting fixtures, etc. In addition, I would also be open to small specialty jobs that I might be able to round up locally where I might be engraving anything from pub beer glasses, to skis, to iphones, to more artistic uses. I am finding that when I think of what I could do, it becomes somewhat overwhelming, so at this point I am trying to narrow it down to where my expertise and training is - architecture (I am a retired architect).

I have the budget to go with one of the big three - trotec, epilog, or ULS, but I am finding my biggest hangup in deciding what system to get is work area size - I think a front & back pass through with at least a 36" wide work area would be essential if the architectural aspect of the work starts to take off and I get, say, a couple of solid core wood door engravings. But then again, if the big projects don't come through, I'd be sitting there with the realization that I spent a hefty premium to get that feature and I don't need it as often as I thought. I also wonder if I might hold off on the 'pass through' option with a laser (thereby significantly reducing the cost) and perhaps add that functionality later through a traditional CNC router, to handle the occasional big stuff. Power is of course also an important aspect to what I'm thinking of, so I would be looking at a 60 -80 watt minimum.

Scott Shepherd
01-31-2014, 1:51 PM
I can't pretend to make the best decision for you to spend your money. Like others have said, it's really up to you. Businesses vary a great degree and what works for me might not work for you. I will say that I have passed over VERY few jobs over the years that wouldn't fit into my 18" x 24" type work areas. The few pieces that I did see, were all 1 off pieces, and not high end work by any means. If I had to think that I spent $15,000 more to get that capability to make $2,000 in the last 5 years, then I'd say, for me, it would be a waste of time and money.

However, I know people that do a lot of larger stuff and they use that side of things a lot. It really just depends on what your business is. If I had to buy a new laser today, it would not be a larger laser. But that's just me.

Ross Moshinsky
01-31-2014, 1:55 PM
Different brand would be the first thing. Probably would not buy the rotary attachment again. Take that money and buy more power. Although our small table is limiting, more power is something I want far more regularly.

David Somers
01-31-2014, 1:59 PM
Don,

One thought since you mention architectural work. A CNC is going to be able to carve much deeper relief than a laser can hope for, if you hope to do that kind of deep bas relief work on big pieces like doors. That might eliminate one need for a really big table. Just a thought.

Dave

Don Corbeil
01-31-2014, 2:13 PM
Yes, David the capability of a router for deeper relief (and I would assume perceived quality) has had me questioning the practicality of doing that aspect with a laser. For those out there that do a lot of medium/larger piece wood carving, do the lasers leave something to be desired with this type of carving work?

Mike Lassiter
01-31-2014, 2:17 PM
Another thing to consider is where you will put the laser. A larger machine means a larger building, especially if you are planning on using pass thru for door and such. I have mine in a 12x32 building and only needed the pass thru on one door to run material in for cutting it. I really need more room around mine but make do.

Jason Hilton
01-31-2014, 2:24 PM
I've done both CNC and Laser 3d relief engraving. You get deeper and more efficient relief from a CNC, but it's also messier. It really depends on the type of work you're doing. I prefer using a laser because it's clean and I mostly do small detail work on pieces 2-5 inches across. However it takes a lot trial and error to get the relief you're looking for, because where a CNC controls depth very accurately with a bit, a laser uses a combination of power and speed determined by a grayscale relief image. Differences in the speed and power change the depth and the quality of the finish on the piece. You also have variations between materials, so you have to account for those differences with adjustments to power and speed. If you don't have enough power, you have to do multiple passes, multiple versions of a source image to control depth... There are a lot more variations with a laser, and 3d relief isn't the best use of a laser engraver. You can get amazing results, but it's not as cut and dried as a CNC. I still prefer the laser, but like I said, I do small work with very specific requirements and very little variation. I've also already done all the trial and error. Of course, I'm nearing the purchase of my own laser, so I'm about to do it all again...

Don Corbeil
01-31-2014, 2:43 PM
That's informative for me, Jason. I've also heard that to get good quality 3D relief with a laser, it involves pretty intensive work with the image processing software to get those grey areas where you want them for depth control. Perhaps it's the same with setting up a cnc router, but it sounds like it may be trickier with the laser.
However, when you get it right, do you see people being as satisfied with a wood engraving done through a laser, or do they tend to prefer the traditional router product? This is an important element in my decision on how to do larger wood pieces.

Joe Hillmann
01-31-2014, 2:46 PM
For what you say you plan to do I question if a laser is the way to go. A lot of what you want to do sounds like larger items than you can fit in a laser.

Take a window for instance. Even if you have front and back passthrough you can't fit the window if it is to wide for the machine, and if the width does fit you may have the problem of lining the part on the x axis if you have to break up the engraving. The same would go for fireplace mantels. You may want to think about sandblasting set up and a plotter for cutting the masking.

Also if you want to do metal engraving with a laser you need to use cirmark to get a mark. I have never used cirmark but there are many threads on the forum asking for help on getting it to work so it seems to be something that takes a lot of trial and error to get it to work. Metal can be masked and sandblasted but the mark doesn't have much contrast.

Wood could also be sandcarved but it takes some skill to get a 3d look to it and even then it will be nowhere near as detailed as CNC.

Glen Monaghan
01-31-2014, 2:50 PM
Another issue with engraving relief in wood is the effect of the wood grain. A CNC's results are not (particularly) affected by the wood grain because the bit cuts through harder and softer layers equally. In contrast, a laser's relief results can be significantly compromised by the grain. The laser will ablate the softer wood more than the harder wood so that a wood such as oak will exhibit a sort of rippling effect in engraved areas where the harder parts are left higher than the softer parts. There's basically no reasonable way to correct for this effect with laser engraving.

Jason Hilton
01-31-2014, 3:07 PM
Don,

For the products I create, no one viewing the end product can tell the difference. But that's because the 3d engrave is only part of the process, I also do staining, painting, and other finishing work. As Glen mentioned, variations in material will cause irregularities that can't be corrected with a laser process, but that CNC will never encounter. I almost always 3d engrave on softwoods.

In terms of artwork, it really depends on your method of creating it. I use 3d software to create my grayscale images for engraving. If I need to tweak, I tweak at the 3d art level and re-export the grayscale image again. I primarily tweak to control the depth and contour of the engraving, so it's easy and quick to alter 3d geometry. I've gotten pretty good at judging the artwork needs for the machine I'm using. Another consideration: artwork for 3d engraving is a lot less portable, because every machine is different in terms of power, speed, lens, etc., so if you create artwork that you need to do a large laser run with, you can't call up a buddy and just send him a file, you'll have to make adjustments, and matching between machines is a big pain, if you can do it at all. CNC on the other hand can usually accept an actual 3d file with defined depth, meaning as long as you use the same bits, feeds, and speeds (in general) you can get the exact same result on two different CNC machines.

If all you're doing is large relief engraving, I would echo many others in this thread and say that a laser is probably not the tool you want.

John Bion
01-31-2014, 3:11 PM
Regarding pass-through capability - I ordered my Chinese Lasers with it, I do not often use the facility, however when I do, I have to match up the the different sections with incredible care or I will err on the X axis or possibly both. The longest piece I handle on the lasers is 6’ (engraved top to bottom). The router is the ideal thing for this, hence my recently purchasing one. The only downside is that you cannot play with settings on a router to achieve darkened/contrast effects as you can on a laser (although depth and line width can be used to some degree on a router - in 2d that is - I have never had the opportunity to try 3d).
Considering the weight of some of the products you are speaking of, this may be an issue for the machine, possibly requiring strain bearing rollers either side to take the weight off of the laser bed. The next problem is the Z travel, a door is not an issue, however a mantel piece could be; not only is sufficient Z from bed to laser head required but also sufficient pass through door depth to where the bed needs to be, most pass through doors are very limited in depth (Z travel).
Doors, window frames etc can of course be engraved on a laser in sections if you are working with the joinery who then complete construction post engraving.

Kind Regards,
John

Keith Upton
01-31-2014, 3:18 PM
It sounds like you need a small to med work area on your laser and the balance of the money should be applied to a CNC router. That would ensure that you had the correct tool for the job a hand. You might need to scale back on the options for each to be able to afford both.

Try looking at what you would need laser wise if you already had the CNC router for the large door type projects. Than do the opposite assuming you already own the laser for the smaller stuff.

David Somers
01-31-2014, 3:44 PM
Don,

Another thought about using a laser for such a large 3D engraving. Speed? If I remember right, folks discussing 3D work on other threads in the forum have mentioned that 3D engraving is slow as well as highly variable due to differences in wood density across summer and winter growth, etc.

Dave

Don Corbeil
01-31-2014, 3:53 PM
It sounds like you need a small to med work area on your laser and the balance of the money should be applied to a CNC router. That would ensure that you had the correct tool for the job a hand. You might need to scale back on the options for each to be able to afford both.

Try looking at what you would need laser wise if you already had the CNC router for the large door type projects. Than do the opposite assuming you already own the laser for the smaller stuff.


With the excellent feedback I'm getting from everyone here, I have to say this is where I seem to be leaning now - starting with a laser system that offers a medium sized work area (possibly with a front door for some oversized flexibility), and with enough power to handle the various materials I would anticipate using. I could do quite a bit with this setup to start with and not break the bank, and then look at adding a traditional CNC router in the future (if demand arises) for those large wood pieces.

Mike Lysov
01-31-2014, 11:21 PM
I would have never bought a laser driven by stepper motors. I did not know their disadvantages over servos for laser cutting until I got one.

Tim Bateson
01-31-2014, 11:26 PM
My 2 cents..... When they say the most machine you can afford, That shouldn't mean the most you can afford payments on. If I had taken a loan out to get started, I would have had to fold years ago. The near zero overhead has allowed me to learn at my own pace without the pressure of financing hanging over my head. Not to mention cash flow was more of a trickle, maybe even dripping the first couple years.

Mike Lysov
01-31-2014, 11:44 PM
I cannot see why CNC routers are faster than lasers. It really depends on your product size, details you need to cut out and whether you can use a wider bit to do less passes.
If I compare with my products and the CNC router I have had it is not faster than my 280W laser for cutting. In most cases my laser cuts faster than the router I have had. We can compare cutting something of 18mm thick MDF where artwork details does not allow using any bit wider than 3mm. Actually it is not even comparable because laser can cut out details much less than 3mm while with the router you are limited to a bit diameter. Anyway lets assume there are no such small details in the product used for comparison.

On my router I wa doing one pass with 2.8mm depth maximum and feed rate was 3200mm/m, usually even less than 3000mm/m.

So for 18mm thick product I had to do 7 passes. That is 3200/7=less than 460mm/m
Now with the 280W laser I can cut through 18mm thick MDF at 480mm/m rate That's already 5% faster. Plus with the router I had a lot of tabs left on my products that I had to remove and it was taken at least extra 2-3 minutes. Yes, the edge is not square with such a thick material and it is charred but i is just a matter whether you and your customers are ok with it.

Rich Harman
02-01-2014, 12:02 AM
I would have never bought a laser driven by stepper motors. I did not know their disadvantages over servos for laser cutting until I got one.

Can you elaborate?

Rodne Gold
02-01-2014, 7:37 AM
Simple - If you doing mainly cutting , power and size , if you mainly doing engraving , thruput... (overall speed to do the job as quick as possible) with both applications a good air assist and exhaust are paramount..
All the other stuff like rotary , stamp modes , pass thru , 3d are just mostly fluff ...
Forget about a laser if you want to do any meaningful 2 1/2d wood , any metal cutting or anything that needs depth control - a CnC router is the way to go.

Dan Hintz
02-01-2014, 8:19 AM
I would have never bought a laser driven by stepper motors. I did not know their disadvantages over servos for laser cutting until I got one.

If a system is designed properly, neither one has an advantage over the other... they operate on different principles, but neither are operated in a domain where their individual advantages can come into play (again, given a good system design). ULS machines work just fine with them, for example.

Scott Shepherd
02-01-2014, 8:38 AM
I would have never bought a laser driven by stepper motors. I did not know their disadvantages over servos for laser cutting until I got one.

I don't know what laser you had with steppers that gave you that impression, but it's a totally false impression. Men were put on the moon by machines that were driven by stepper motors. Universal lasers have used steppers for a long time now and their accuracy and quality on cutting is excellent.

David Rust
02-01-2014, 10:00 AM
A larger engraving area and more power.

EXACTLY.... my area is 24"x 18", I just processed a 23.5" by 35" coffee table top, a full top engraving. The customer cut the top down in size to match my engraver then framed the top to get it back up to the size he needed... As Joe said "larger engraving area and more power" I had to run this job in halves... half way through I had to rotate the tabletop and painstakingly line up everything so that the interruption of the engraving at the middle of the coffee table was not noticeable...

Here is a pic...

281309281310

Don Corbeil
02-01-2014, 10:15 AM
If a system is designed properly, neither one has an advantage over the other... they operate on different principles, but neither are operated in a domain where their individual advantages can come into play (again, given a good system design). ULS machines work just fine with them, for example.

Dan, This is something that got my attention during my research. What advantages and disadvantages would the servo motors have compared to the steppers? I have only seen speed mentioned as an advantage. Are there other issues with one over the other? Reliability? I have to admit that at first blush it appears the servo motors have the upper hand with the speed issue, but I know you have been happy with the ULS stepper motors.

Bruce Volden
02-01-2014, 10:26 AM
Back in 1995 I had virtually no knowledge about laser engraving. There were only a couple of choices back then. I had no Corel Draw training.
I took a tour of LMI (now Preco) in Wisconsin to learn more and ended up buying my first system. I figured if something went wrong I could always throw it in the pickup and bring it back right? It had a 25 watt 30" X 11" engraving area, stepper drive, 2 year bumper to bumper warranty!
The thing was a tank and I purchased another one 2 yrs later.
Biggest complaint-weight!

Bruce

Don Corbeil
02-01-2014, 10:40 AM
Thanks to everyone for helping out here. It has certainly shed light on a number of issues

Has anyone regretted not getting a vacuum base for thin work (like paper), or is this something that is fairly easy to work around?
Also, the rotary options - chuck/cone vs roller systems. And this is important because it appears the Epilog only offers rollers. I have read that rollers may become problemmatic for precision detail work due to the possibility of minute slippage on some pieces?

Don Corbeil
02-01-2014, 4:45 PM
Back in 1995 I had virtually no knowledge about laser engraving. There were only a couple of choices back then. I had no Corel Draw training.
I took a tour of LMI (now Preco) in Wisconsin to learn more and ended up buying my first system. I figured if something went wrong I could always throw it in the pickup and bring it back right? It had a 25 watt 30" X 11" engraving area, stepper drive, 2 year bumper to bumper warranty!
The thing was a tank and I purchased another one 2 yrs later.
Biggest complaint-weight!

Bruce

I am in a similar position now - I know very little about laser engraving but am very excited about learning - I am forever a student, I'm afraid. The only applicable skill I can bring into laser work is a pretty good working knowledge of CAD software and a some other graphics/imaging programs. I used these extensively in my previous life as an architect. I'm hoping that it might give me a little bit of a leg up on the learning curve.

Mike Lysov
02-01-2014, 5:36 PM
Can you elaborate?

Steppers have problems with maintaining constant speed in one job if this job has some complex shapes(a lot of change of cutting directions or small details) and supposed to be cut at high speed. Power settings are stay the same for the whole job. So when speed varies within a job and often drops(sometimes a few times less than set) on turns/angles/small details while laser stays at the same power it removes more material at the bottom and creates angled cut.

And that's only a part of the problem. Because of problems with acceleration/deceleration for steppers their motion controller is there to decide whether you can do cutting at specific set speed or not. Simply you have no control over cutting speed and even with a quite powerful laser you may not be able to cut small and/or thin designs faster than the same can be done on lasers with much less power but with servo motors.
I believe it is very a bad decision from engineering point of view to use stepper motors on laser cutters. Somebody may argue that there are better steppers that are more expensive that do not have all these acceleration/deceleration problems and can run at constant speed on any design even if a job speed is set quite high but why then they have not been used in my laser for example. It is quite expensive(over $38 000) and I do not believe these better steppers would make the whole system is much more expensive.

Dave Sheldrake
02-01-2014, 5:49 PM
Gantry or Flatbed Mike?

$38k for a 280 watt twin tube is cheap suggesting that savings were made somewhere, from what you have said likely in the electronics and control system as well as the step motors. High speed ,high quality, servo driven ball screw systems are great but they aren't coming to market at much under $100k for an average one and closer to $500k++ for a good one. $38k for a laser in this industry is still in the higher end hobby use section so price point is important to the vendors I guess.

cheers

Dave

Scott Shepherd
02-01-2014, 6:23 PM
Steppers have problems with maintaining constant speed in one job if this job has some complex shapes(a lot of change of cutting directions or small details) and supposed to be cut at high speed. Power settings are stay the same for the whole job. So when speed varies within a job and often drops(sometimes a few times less than set) on turns/angles/small details while laser stays at the same power it removes more material at the bottom and creates angled cut.

I'm sorry, but that's incorrect. Universal's driver uses an algorithm that resolves all the things you said steppers cannot do. I don't know what what system you have, but I can assure you that our Universal with steppers is probably the most accurate machine we have used when it comes to vector cutting. We cut thousands and thousands of very tiny parts with tight tolerances. I might have 200 of the parts on one sheet of material and each part has 4 features that are tightly controlled. Across the entire table, the machine is deadly accurate. I've tried it on Epilogs and the Trotec and I cannot get that level of repeatability and tolerance from either. We can get really close on the Trotec and I'm sure with some time and experimenting, I could get it tuned in, but we haven't done that because the Universal just nails them perfectly every time.

Joe Hillmann
02-01-2014, 7:08 PM
Steppers have problems with maintaining constant speed in one job if this job has some complex shapes(a lot of change of cutting directions or small details) and supposed to be cut at high speed. Power settings are stay the same for the whole job. So when speed varies within a job and often drops(sometimes a few times less than set) on turns/angles/small details while laser stays at the same power it removes more material at the bottom and creates angled cut.

And that's only a part of the problem. Because of problems with acceleration/deceleration for steppers their motion controller is there to decide whether you can do cutting at specific set speed or not. Simply you have no control over cutting speed and even with a quite powerful laser you may not be able to cut small and/or thin designs faster than the same can be done on lasers with much less power but with servo motors.
I believe it is very a bad decision from engineering point of view to use stepper motors on laser cutters. Somebody may argue that there are better steppers that are more expensive that do not have all these acceleration/deceleration problems and can run at constant speed on any design even if a job speed is set quite high but why then they have not been used in my laser for example. It is quite expensive(over $38 000) and I do not believe these better steppers would make the whole system is much more expensive.



I would have do disagree with the first paragraph you wrote. Yes they will slow down around corners but as it slows down the power to the laser is also reduced to make up for it.

Mike Lysov
02-01-2014, 7:11 PM
Gantry or Flatbed Mike?

$38k for a 280 watt twin tube is cheap suggesting that savings were made somewhere, from what you have said likely in the electronics and control system as well as the step motors. High speed ,high quality, servo driven ball screw systems are great but they aren't coming to market at much under $100k for an average one and closer to $500k++ for a good one. $38k for a laser in this industry is still in the higher end hobby use section so price point is important to the vendors I guess.

cheers

Dave

It is a flatbed style.
I have just had a look at my motor labels to check how much powerful they are and I am surprised. These are not steppers, they are servos. Then I am completely lost why I am having all these problems with speed dropping and acceleration/deceleration. They are both made by Delta. X motor is 0.4KW and Y motor is 0.1KW. Do these problems come from the fact they do not have too much power or because of the motion controller is set to do it.

Mike Lysov
02-01-2014, 7:17 PM
I would have do disagree with the first paragraph you wrote. Yes they will slow down around corners but as it slows down the power to the laser is also reduced to make up for it.


Mine does not seem to care about reducing power when it decides to slow down.

Dave Sheldrake
02-01-2014, 7:43 PM
Gantry weight and controller I would think Mike, gantry mounted tubes by any chance? (I get the same issues when trying to cut fast on the flatbeds)

cheers

Dave

Mike Lysov
02-02-2014, 12:33 AM
Gantry weight and controller I would think Mike, gantry mounted tubes by any chance? (I get the same issues when trying to cut fast on the flatbeds)

cheers

Dave

Will it help if I get both motors replaced with double/triple power motors? There are 600W, 750W and 1KW servo motors made by delta and drives for them available. Depending on a level of upgrade it won't cost me more than $2000-$3000 If it is just a matter of fitting new motors and replacing drives I may be able to do it myself but if something needs to be done in terms of reprogramming the motion controller then I think I will need to find some extra help to do it.

Dave Sheldrake
02-02-2014, 6:30 AM
Hi Mike,

You end up fighting the laws of motion, faster acceleration / more speed = more effective mass in the gantry (it basically weighs more). Doubling speed will make 4 times the energy required to change directions.The big flatbed machines aren't designed to be quick or to make small turns but more for cutting out large items at reasonable speeds.
My biggest laser costs 100x what the mid size machine next to it cost and yet is 5x slower on linear speed.

cheers

Dave

Mark Ross
02-02-2014, 2:44 PM
We got an Epilog 36EXT 45W and ended up buying a second with 75W power. Bigger size (cut 4X8 sheets of acrylics would be nice...but not for 250k). So I would say more power. Something with a work door, to do longer pieces of material (but do them very accurately) would also be nice.

Mike Lysov
02-03-2014, 5:48 PM
Hi Mike,

You end up fighting the laws of motion, faster acceleration / more speed = more effective mass in the gantry (it basically weighs more). Doubling speed will make 4 times the energy required to change directions.The big flatbed machines aren't designed to be quick or to make small turns but more for cutting out large items at reasonable speeds.
My biggest laser costs 100x what the mid size machine next to it cost and yet is 5x slower on linear speed.

cheers

Dave

It is not really that big Dave ( http://www.youtube.com/watch?v=QJWtKWGAu3c ).

Kev Williams
02-03-2014, 7:30 PM
Wow-- this thread sure brings out the variances between machines!

I have 3 pretty much different lasers, so I have a few things to add:

As for "power on slowing down for corners"... Not an issue on my '96-ish 25w ULS or 2003 40w NH LS900. However, there's no algorithms to automatically figure that out for me on my Chinese Triumph. Right in the "cut" menu is is a "corner power" setting, and you just have to experiment with various power settings to see what works. Part of the fun I guess. Or the agony of the 'learning curve', whichever fits best ;) ... fwiw, the corner power I enter is about 40% of the full power I enter.

as for "larger table with more power". That's what I went for with the Triumph! But sometimes less is more. If you need crisp, dainty detail on Romark, you ain't gonna get it with an 80 watt Reci attached to a 51 x 36" sized machine (But I AM still workin' on it!)

And finally, machine speed... Back in the old days I used to sit and watch my XT5000 engrave something, and I'd complain out loud "who's the idiot who digitized that "U"?? It starts on the right side and goes left!! What a waste of time!!" Seriously, I did-- but that's because the job I was watching had to finish before I could to the next job. Kept trying to figure out ways to speed up the machine!! And finally, I did find a sure fire, 100% guaranteed-to-work way to cut my machine time-- in HALF!!





--- Buy another machine! And as you can see in my signature, I kept that habit up! But one thing's for certain, it's been a LONG time since I've worried about which way a "U" engraves. Or how fast my new IS7000 will cut holes in 1/8" thick aluminum. It cuts plenty fast enough to suit me. These days I start one machine, then start a job on another. How long it takes any one machine to do any one thing is rarely an issue for me. But recently I HAVE been waiting on my laser machines, which is why I bought the Triumph. And even with the 3rd laser helping out now, I'm considering getting a 4th...

Now, I don't condone just going out and buying a dozen machines. But if you find the machine you're using seems too slow, then seriously consider getting another machine!

So as to the original question "first laser purchase - what would you have ordered (done) differently?" -- I would say "not wait so long to buy the second one!"

:)