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Dave Chase
08-23-2006, 3:14 PM
Hi All,

I'm new to the forum and hope to obtain some advice on purchasing a laser. Has anyone had experience with the Accuris lasers? I think they are made by Pinnicale. Signwarehouse has them on special until the end of the month and I was thinking about taking advantage of it. Any suggestions? Also, does anyone have experience engraving/marking chrome - plated aluminum? I'm wondering what type of wattage I would need to do this. Thanks!

Mike Mackenzie
08-24-2006, 3:36 PM
Dave,

First off the Accuris lasers are manufactured by a company in Taiwan they are LTT.

http://www.laser-cutting-machine-video.com/general_marketlils-3.asp.htm#

Sign warehouse does not mfg any laser system that I know of.

For doing chrome plated aluminum you will need at least 50 watts if not more make sure that you get samples done on your material to see what wattage it took to do it efficiently.

Mike Hood
08-24-2006, 4:37 PM
I think they are manufactured by (for?) GCC and then inported under their license and LaserPro.

I just ordered a Pinnacle ZX-40 this afternoon from them. Looking forward to seeing how it works out. :)

Dave Jones
08-24-2006, 6:17 PM
Most of the Pinnacle/Sign Warehouse lasers are GCC, but the Accuris ones are LTT, and Sign Warehouse had another one that was discontinued this spring made by a third company.

LaserPro is a different company that also imports GCC.

Mike Hood
08-24-2006, 6:39 PM
Good point. You're 100% correct. The Accuris is the same as the ILS-III and the Pinnacle the same as the Laserpro models.

Dave Chase
09-22-2006, 12:23 PM
I think they are manufactured by (for?) GCC and then inported under their license and LaserPro.

I just ordered a Pinnacle ZX-40 this afternoon from them. Looking forward to seeing how it works out. :)

Mike,

How is your new Pinnacle working out?

Mike Hood
09-22-2006, 3:19 PM
GREAT!

I keep meaning to post something on here about my experience, but have been busy.

Here's a run-down. I was originally looking at something in a 25W-30W range as speed or higher power wasn't a huge concern. My primary business plan keeps me below 1/4"-3/8" or so in cutting requirements and most in Depron foam anyhow. I have played with granite engraving and such, but mostly cutting.

I looked very closely at the Unversal, Epilog and Pinnacle (GCC) lines and when the day was done, the ZX fit my bill perfectly.

I ended up with a 40W Pinnacle ZX, vector table, rotary attachment, air handler and software package that suited my needs perfectly. I REALLY like the large bed size and the ability to pass material straight through.

I build custom model airplane prototypes, so much of my work is light ply, 1/4" at worst. The laser has performed flawlessly and walks through everything I've put it up against so far. Joseph was a wonderful resource and got everything moving along and delivered without issue.

I've been burning everything in sight. :)

Jin Lee
09-22-2006, 3:36 PM
Well, I'm definately a newbie to laser cutters/engravers and have been reading all the info out there that I could find as well as doing as much research as possible on the internet. I've found that the big companies most people go with are: Epilog, ULS, Pinnacle or Accuris.

Doing some looking around on eBay and other sites, I've found alot of auctions from companies based in Taiwan that sell lasers for 25%-50% of the price of a comparable sized laser from the big companies I listed above. This is a HUGE savings... enough for me to stop and think about it.

I mainly do model and prop-making as a side business and would be getting a laser not as my main source of income but to supplement my income. I'm not worried about cranking out as many pieces as possible in an hour and I definately wouldn't be putting an enormous stress on the laser. The difference in price ($4,000/Taiwan made vs. $11,000+/US made) is too large to just ignore and chalk up to quality. Has anyone on these boards bought/used these Taiwanese company models? If so, how reliable were they and how was the support?

- J.

Joe Pelonio
09-22-2006, 3:51 PM
There are previous posts on this if you search. I don't think we've had any long term reliability reports on them yet. By the way, don't go by what most people bought. Most of us were far from experts when we bought
our first laser, and didn't have this forum as a resource until after we had already bought. Good to see people checking in prior to making a decision.

Mike Hood
09-22-2006, 6:16 PM
That's very true. I work just down the street from Coherent, and was happy to hear they supply the tubes for the Pinnacle ZX. I also like the ability to swing open the doors for larger pieces and the 38" working width of the bed.

I've only had it a few weeks now, but it performs everything as advertised so far and has given me no issues at all.

I work with a lot of lite ply and was concerned that it may give the laser a hard time, but it cuts 1/4" with no problems. That's about as heavy as I need. It's a REALLY neat tool and fast.

I agree with everyone talking about what's best. I suspect if it does the job, and fits your budget... it'll be your best as well. :)

Dave Jones
09-22-2006, 7:26 PM
I've found that the big companies most people go with are: Epilog, ULS, Pinnacle or Accuris.

Well, actually Pinnacle is not a manufacturer, they are a distributor. The Pinnacle and Accuris lasers are actually made by GCC and LTT, which are both Taiwanese companies.

The difference between these and the cheap lasers you mentioned are that the cheap ones use outdated types of laser tubes (glass tubes using water cooling) which do not provide very uniform outputs and have very short life.

I can't speak to the quality of the X/Y tables on those cheap units, as I have not taken a close look at them, but I believe I read that they are stepper motor based. The more expensive ones use closed loop servo systems with optical encoders. When a stepper motor makes a mistake it can't correct for it. So the rest of the engraving/cutting will be done wrong until the table resets itself. That's not so bad if you are working on some low cost raw material and don't mind throwing work away if that happens. It's a different issue if you are engraving some object that belongs to somebody else or is expensive.

I would consider it similar to one person being happy with a low cost, low quality tool for their workshop, while the next person only being happy with a high quality tool that will last a long time and do a better job.

Richard Rumancik
09-22-2006, 8:10 PM
Has anyone on these boards bought/used these Taiwanese company models? If so, how reliable were they and how was the support?

- J.

I have the LaserPro Mercury 30w from GCC purchased in 2000. As far as reliability - I replaced the mainboard under warranty after a year. The laser tube failed after 30 months just before warranty expired. It was a Synrad tube. I had the x-motor fail at 37 months (out of warranty). The x motor takes a lot of abuse when raster engraving as the bearing direction is constantly reversing so this failure wasn't surprising. The gas spring on the lid failed at 37 months - I paid $60 for one but the second one failed shortly after. They need to be replaced in pairs.

Support - GCC wants users to go through their rep on everything. But I did not find this to work 100%, as my rep did not always has access to a LaserPro to try what I asked. So ultimately the question would go to GCC Taiwan and often get lost. To be honest a lot of my questions went unanswered and I had to figure things out and accept the limitations of the machine. I use it to make industrial parts as well as decorative so accuracy is important to me. Since my questions and problems were unique, a lot of times I was told that nobody else was seeing the problem. Perhaps support has improved; I have not had contact with GCC for some time.

Dave Fifield
09-23-2006, 9:14 PM
There's an Epilog Legend 32 for sale on the SMC classifieds right now....

:Dave F.

Mike Null
09-24-2006, 9:39 AM
I think there is a bit of an error in the the comments regarding stepper motors. First, Universal uses stepper motors, I believe across their entire line. (my 8 year old ULS had steppers and when I shopped for a new machine recently ULS was still using steppers) They are both accurate and somewhat more reliable than servos. Servos are more expensive and faster.

Dave Jones
09-24-2006, 1:39 PM
A stepper motor system that does not have an encoder has an inherent weakness in that it does not know where it is. All you can do is count the pulses you send to it and hope that the motor actually turned when it got the pulse. You have no way of knowing for sure.

If there is resistance to the movement (poor lubrication, particles on the thread, gearing, or rails, etc...) or if there is a problem with one of the windings in a stepper (which has anywhere from 4 to 16 coils in it), then the stepper could miss a step and the control circuit would never know.

With a closed loop system using an encoder and either a stepper or linear motor the control circuit has feedback as to whether the motor actually moved the mechanical parts to where they were supposed to go. (yes, steppers can be used in closed loop servo systems too)

Stepper motors are chosen by a designer because they are cheap and their drive circuits are cheaper than linear motor drivers. Without an encoder a stepper motor is not a more reliable way to move a mechanism. The cheap Chinese laser tables use no encoders, and are not as reliable as ones that use closed loop servo systems. I'm not talking about reliability in terms of total failure. I'm talking about reliability of the mechanism being in an exact known position every single time.

I've been designing electronic systems for 35 years, including industrial equipment using both steppers and linear servo motors, and have an intimate knowledge of both systems. I'm just giving an overview here. Servo systems also can have problems, such as dirty encoders, but in general give more reliable positioning of mechanisms.

Mike Null
09-24-2006, 7:42 PM
Dave:

I will defer to your technical expertise while standing by my remarks. I belong to two engraver's forums and in doing a substantial amount of research prior to the recent purchase of my new machine looked carefully at the problems reported by the members.

1. Accuracy problems were relatively rare.
2. I cannot recall a single problem identified as a stepper motor problem.
3. There were numerous complaints about the x motor, a Servo, on the Epilog machines. Some on this forum as recently as a few days ago.

Your remarks dealt with reliability in positioning, mine with motor life. I have read many other posts which said it was common to replace motors as often as yearly. I never replaced even one in 8 years with my ULS.

My new machine does have Servo motors but my interest was more in productivity and had I found a machine as fast with stepper motors I would have had no qualms in buying it.

Bruce Volden
09-24-2006, 10:59 PM
Dave:

I will defer to your technical expertise while standing by my remarks. I belong to two engraver's forums and in doing a substantial amount of research prior to the recent purchase of my new machine looked carefully at the problems reported by the members.

1. Accuracy problems were relatively rare.
2. I cannot recall a single problem identified as a stepper motor problem.
3. There were numerous complaints about the x motor, a Servo, on the Epilog machines. Some on this forum as recently as a few days ago.

Your remarks dealt with reliability in positioning, mine with motor life. I have read many other posts which said it was common to replace motors as often as yearly. I never replaced even one in 8 years with my ULS.

My new machine does have Servo motors but my interest was more in productivity and had I found a machine as fast with stepper motors I would have had no qualms in buying it.


Ditto here! 2 machines with steppers 0% miss rate and these machines are going on 12 years now!!


Bruce

Dave Jones
09-24-2006, 11:05 PM
I've seen the posts about the Epilog X axis motors failing. I've seen enough of those to guess that it isn't a fluke, but probably a design flaw. But I wouldn't take that as an indication of servo motors being more likely to fail than steppers. I'd take that as an indication that Epilog either underspecified their motor, or designed a driver board that puts out too much voltage or current for the motor they are using.

Whatever the cause, you're right, it is a problem, but I don't see it as evidence of steppers being better than servos. I've seen lots of steppers fail.

Mike Hood
09-24-2006, 11:46 PM
In the "real world" I'm an electrical engineer and there are many other differences that one could compare. All things being equal (money... servos cost more as a rule)... there are some other advantages of servos over steppers:

Speed
Resolution
Acceleration compensation
Noise
Positioning error
Relative home positioning
X-Y transition (no stepping or "jaggies")

All of these concerns are relatively small in real application though. Micro-steppers should work just as well as most servos, but in my case... I chose servos.

Jin Lee
09-25-2006, 1:52 PM
Well, after much reading and fretting and asking of questions, I decided on an Epilog Mini-18 over the cheaper "made in China" machines. I was concerned about the servo motors burning out but after speaking with a rep, my concerns have been alleviated.

He mentioned that the Epilog Mini's are designed to work at 60 inches per minute as opposed to the bigger ones that are working at 120 inches per minute. So, the servo's are worked much harder in Epilog's bigger machines. The Mini's have had almost no problems with their servo motors burning out. I was also told that to replace the X-axis servo motor in the Epilog Mini-18 would cost around $250-$300... which I didn't think was all that bad. I was afraid it would be much worse.

So, the deposit is in and in a few weeks I'll post again when I have it in my hands to play with! Thanks again for all the advice everyone! Great informative forum here and I hope I can add to the productive exchange of information over time.

- J.

Dave Jones
09-25-2006, 2:50 PM
be aware that the standard warantee is 1 year, so if a motor or anything else did burn out in that year, they ship a new one free overnight. Before the year is up you can renew the warantee for another year or two.

Mike Hood
09-25-2006, 3:46 PM
"I decided on an Epilog Mini-18 over the cheaper "made in China" machines. I was concerned about the servo motors burning out but after speaking with a rep, my concerns have been alleviated."

Not sure what your rep's "concerns" were, but many I was warned of before I purchased mine were completely incorrect. I purchased a "made in China" laser and have had great luck so far.

Lot's of hype out there. These are commisioned sales guys and that's expected.

I've now purchased from Sign Warehouse twice (Vinyl Cutter & now a Laser) and they've been very professional and helpful. It all comes down to that in the end game.

Goodluck and let us know what you come up with first. :)

Kim Vellore
09-25-2006, 3:54 PM
My opinion on stepper Vs Servo as applicable to a laser machine is

Stepper:
Great for vector cutting, poor for raster because of speed
Biggest advantage: (IMHO) the steppers are disabled (in most machines I have seen) after the print job so one could just move the head by hand to where ever one wants to and place the work piece there. Great for development and prototyping so you can use all the odd shaped waste materials laying around.

Servos:
Great for raster, it is like music and dance when rastering esp. at high speeds.
Disadvantage, you have to push multiple buttons to disable servo or move it via buttons to get the head to the location you like and reset as home. Not available in all machines like my TT if I disable the motors I have to reset the machine. For quick use of odd shaped waste materials lying around I have to modify the drawings or go through pushing many buttons on the laser to redefine home that is also too time consuming.

In general for industrial use there is a lot of debate on which is better servo or stepper, and one cannot say servo or stepper is better it is all based on application. There are also many applications where only a servo will work or only a stepper would work. In the case of laser engraver both would work with the advantages and disadvantages I have mentioned other than the cost. It is just my opinion because a colleague of mine has a laser with stepper which I prefer to use for prototyping and use mine for volume.

Kim

Rodne Gold
09-25-2006, 5:14 PM
Kim , Your positioning issues are a function of your driver and laser not the motors , I have a feedback servo machine and can move my head manually wherever I want at any time , including pausing a job , moving the head and restarting at the exact position.
I have both servo and stepper based machinery in my shop , I have never had a stepper burn out and have replaced many DC servo motors , but would not consider buying an open loop stepper machine again.
Its nothing to do with the motors , its to do with the utility of the machines. With no feedback in a machine , there are a huge amount of things the machine cannot do or cannot do repeatably and accurately.
There are huge advantages to feedback systems and the use of steppers without feedack on NC controlled lasers or engravers , is , to be blunt , primitive tech.
Separate the motor from the motion control system when comparing the 2 types of motor , steppers can have feedback and then their useage becomes far less of an issue.

Joe Pelonio
09-25-2006, 5:46 PM
I've seen the posts about the Epilog X axis motors failing. I've seen enough of those to guess that it isn't a fluke, but probably a design flaw. But I wouldn't take that as an indication of servo motors being more likely to fail than steppers. I'd take that as an indication that Epilog either underspecified their motor, or designed a driver board that puts out too much voltage or current for the motor they are using.

Whatever the cause, you're right, it is a problem, but I don't see it as evidence of steppers being better than servos. I've seen lots of steppers fail.
Just to add that the Epilog x-motor failure (that I just had) WAS a design flaw. Looking at the new bracket design compared to the old it looks to me like the design flaw was allowing too much stress on the motor shaft causing it to eventually bend.They corrected it with a new version of the bracket, and they did not charge for the new motor and bracket even though it was way out of warranty.

Dave Jones
09-25-2006, 6:10 PM
Mike, when Jin Lee was talking about the cheap Chinese lasers, I'm pretty sure he was talking about those $2000 lasers with the glass tubes. Not the higher quality machines like the GCC/Laserpro.

Kim Vellore
09-25-2006, 7:51 PM
Rodne,
That is one of the key features that I'll be looking in my next machine. Which is the laser you have with servos that you can move the head manually without having to push a bunch of buttons.
Kim

Mike Hood
09-25-2006, 10:39 PM
Positioning a servo head can't be easier... Simply move the head to wherever you want to start the job and hit "start". With servos you don't have to disable anything... on a Pinnacle, just select "Relative" in the driver... and that becomes the new start point.

Great if you want to quickly etch something. Just send the job over to the cutter, drag the head over, hit start. :)

Dave Jones
09-25-2006, 10:49 PM
My Epilog Mini-24 has that feature, and I know the 36EXT does too. I assume most of the newer Epilogs do. You hit the "X/Y Off" button and then hit the "Go" button. Then you can grab the mirror/lens assembly and slide it side to side, and grab the X rail and slide it forward and back. Once it is in the position you want you can set that as a temporary home position and start lasering.

Rodne Gold
09-26-2006, 3:24 AM
The GCC machines (at least my explorers and spirits) allow that Kim , apart from which , they have some great "starting and ending " position options. Best feature IMHO in respect of positioning is the ability to tell the machine the start point is the centre of the engraving , very easy to find a centre in respect of irregular objects.

Mike Hood
09-26-2006, 11:53 AM
Really handy for pens and small stuff. For the first tries I was aligning everything "relative" and then sliding the arm around until I got what I liked. That is a really nice feature of the GCC machines (LaserPro or Pinnacle).

Being able to move the x/y at any time to a fresh area of material is a huge plus.

Rob Bosworth
09-26-2006, 1:02 PM
What you are all saying is true. At least from a theoretical point of view. I probably rebuild/ refurbish ~ 60 machines per year. In the last 10 years, I have replaced maybe 15 stepper motors on stepper motor based laser engraving systems. (I originally figured maybe 10, but thought I would round up.) I have usually replaced the stepper motors because the system was losing position. In that same amount of time, I have probably replaced 60 servo motors. I usually have to replace the servo motors because they lose position while laser processing. Were the servos bad? Sometimes. Were the rotary encoders mounted on the end of the servo motors bad or encoder strips bad? Some of the time. Were the signals going in and out of the amplifier boards bad? Sometimes. All I know is I have replaced a lot more servo motors than I have stepper motors.

A closed loop servo system is a very complicated electronic system. You have many components involved in this motion control package. The systems that have been very fast, reliable, and extremely accurate usually use huge servo motors and a very complicated, fast computer controls package. Closed loop servo motors can drive motion systems at very high speed. But to track where the motion system is at an exact moment, requires some fairly fancy computing capability. Not only does the, let's call it the CPU, have to know what it is supposed to be doing and where, it must also be able to anticipate what is coming up and how it is going to be able to do what it is supposed to do. Ramp up. Ramp down. Maximize, minimize. Sinusoidal accelerations. Then let's throw in vibration and velocity. To say nothing about how it gets back on track once it has "lost" its position. And every function has to be as smooth and consistent as can be, or you see it in the laser processing on the finished product. These need to be very sophisticated motion controlled packages if they are going to run correctly.

Now, let's look at how all these machines are marketed and sold in the U.S. All of the manufacture's send these machines out to a guy (gals included in the guy statement cause I'm trying to be PC) like you and me. 99 out of 100 times, these machines run flawlessly. Then one day, you notice the engraving or cutting is jiggity. Pick up the phone and talk to tech support. Best guess scenario, based on our verbal description, the tech support group shoots you out a replacement motor. Next day we get the replacement motor, remove the old one, install the new one, put everything back together only to find out it doesn't fix the problem. Now we figure it is the encoder strip and/ or the strip reader, .... This troubleshooting of a complicated motion control package can be very taxing. And we are doing it on the phone.

I don't mean to say one machine is better than another. All of the machines we have worked on are very reliable. But our having an open discussion on this forum about one technology being better than another technology based on theory is not doing a true service to some of other forum members. All of the machines we have handled a very fast, very reliable and will all do about the same thing. It has been acknowledged by most in the industry that some of the stepper motor machines vector cut smoother and faster than most of the servo based machines. And it is close to acknowledged that some of the servo machines have faster lineal speeds for raster engraving, which shows up best in small engraving areas as opposed to full table travel. But in the end, both technologies do a very good job of laser processing and opened up a treasure trove of opportunities for all of us who use these machines.

Mitchell Andrus
09-26-2006, 2:19 PM
I find it amazing that I can move the head of my Spirit to any location and it will start cutting without looking for a fixed 'start' point. Makes last minute focus adjustments a snap.

Mitch