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James L Barber
06-07-2010, 10:17 PM
Hi folks, 1st-time poster.

I'm a long-time CNC router/mill owner who primarily uses the machines for engineering prototypes. I'm considering both small and a large-format laser engravers/cutters for primarily the same purposes, although I'll want to be able to engrave my share of beads and trinkets as well.

My question is: How does the output quality of (for example) a Rabbit compare to that of a Western-built machine? I'll define quality as clarity of line and positional accuracy, to start. Speed is a factor as well, but for the moment I'm more interested in comparing the output quality.

For what it's worth, I own and operate imported CNC router/mills and once having learned the ropes don't have many complaints. Laser engravers are a new thing, though, so I'm trying to avoid making any expensive mistakes.

Thanks,
--jim

Joe Pelonio
06-07-2010, 11:14 PM
If you check the old posts here on the subject, it seems that most of the trouble with the inexpensive imports is related to poor support, and glass tubes that don't hold up, rather than quality of output. Those members having good luck with their Chinese machines are very happy with them
and I suspect they are among the more mechanically adept and able to handle issues themselves. Once dependent upon your laser for production work, it's very inconvenient to be down and without help and parts even for a day or two. If you are considering a Rabbit or similar, look for a local dealer that has been around a while and provides good support, rather than buying online from a dealer that simply imports and resells them.

James L Barber
06-08-2010, 2:07 AM
Thanks, Joe.

That's actually how I found this forum - 'Googling' with different search strings in search of info. As you said, I did find support complaints but nothing much specifically about the output quality. I suppose I was looking for a positive, rather than a lack of negatives. :-)

Having owned and repaired Chinese CNC router/mills I'm not _too_ concerened about end-user tech support beyond parts availability, and I'm in the habit of buying redundant spares for everything. One thing I don't know is the shelf life of a Chinese glass tube, though. Based only on my experience with older glass RF transmitting tubes, you get a few years of storage before the tube internals emit enough gas molecules to ruin your day when you pull them off the shelf. That's one of the reasons manufacturers changed over to metal and ceramic materials . . pure speculation on my part but I wonder if that may also be the reason that the metal laser tubes last longer?

Anyway, thanks again for the reply. If the output quality is very good then that gives me more confidence to make a decision. My actual purchase would be from one of the US importers, and as above I'll buy lots of spares up front assuming they won't be available forever.

--jim


If you check the old posts here on the subject, it seems that most of the trouble with the inexpensive imports is related to poor support, and glass tubes that don't hold up, rather than quality of output. Those members having good luck with their Chinese machines are very happy with them
and I suspect they are among the more mechanically adept and able to handle issues themselves. Once dependent upon your laser for production work, it's very inconvenient to be down and without help and parts even for a day or two. If you are considering a Rabbit or similar, look for a local dealer that has been around a while and provides good support, rather than buying online from a dealer that simply imports and resells them.

Rodne Gold
06-08-2010, 3:16 AM
Glass tubes seem to have a life of 600 hrs - thats what the mnfgrs of some chinese machines have told me - tubes seem to cost between $200 and $300 depending on who supplies and wattage.
The sealed mainstream C02 tubes are supposed to last 20 000 hrs - I have never gor more than 3 yrs at 6-8 hrs a day out of any i have - IE round 4000 hrs and they cost upwards from $2500.00
Key to getting max life out of a glass tube seems to be really good cooling and chillers etc.

William Jenkins
06-08-2010, 4:59 AM
Hi there, I own a Chinese unit, the problem is the support. I ordered my unit from Artsign, Jackie is the owner and they are absolutely useless. There was a problem with my air filtration unit upon delivery and it is 4 months later and still not resolved. Your on your own figuring things out, this company is the worst I have ever dealt with. Some others may be better I don't know, but I would think long and hard before I went down that road again.:confused:

Dan Hintz
06-08-2010, 6:29 AM
Mechanically inclined or not, when certain electronics pieces go belly up, there's little even a trained electronics tech can do. If the motherboard dies, it's not as simple as ordering a new one. The Chinese systems almost always use hardware dongles, change firmware revisions like they change their daily outfit, have poor quality control during manufacture, etc. The difference in firmware revisions can cause all sorts of issues as they don't stock older systems, they sell what they have on hand and then that's it. If your dongle doesn't work with the firmware on the replacement board, you're stuffed.

And when you can get replacement parts, they gouge you on the price, almost to the point of a new machine looking very attractive from a financial standpoint. Tubes arrive broken out of the box, or they last for years... it's a problem with their quality control, so you never know if you're going to get lucky, but you're rolling the dice. Even replacement tubes show up dead.

For the small investment, Chinese machines with glass tubes can be extremely useful... if you plan to use it in a production environment, you would be a real risk taker to try anything other than a reliable system with good support.

Mark Ross
06-08-2010, 8:20 AM
James,

All I can add is that as far as our Epilog 36EXT goes, tech support and service has been nothing less than extraordinary. We may soon be busy enough to add another machine and there won't even be any debate about who we add. I wish they made a 4' X 8' table tho...

For our business, we can't afford to be down and I doubt I would get the Epilog level of support with a Chinese machine.

greg lindsey
06-08-2010, 9:17 AM
I'll add my .02, 11 years ago I bought 2 used Epilog engravers, got great support from my distributer ( the one that sold them to me) Roy Brewer(he and his crew deserve the props), but where I was really shocked was the level of support that I received and still do to this day, from the tech support staff from Epilog.

In all my years of business I have never been treated so well in any tech support system as from these guys, even though I didn't buy new machinery from them, they have always been there for me. In those 11 years the only repairs I have made to these machines has been mirrors and lenses ( now that being said, probably just jixed myself):eek:, now I've bought another Epilog and the cycle continues.

BTW, those two old machines run an averave of 9 hours a day each. Can't be just luck, otherwise I would'nt be typing this, I'd be spending my Lottery winnings on good boose and cheap w....., nevermind. LOL:D

James L Barber
06-08-2010, 3:33 PM
Thanks for all the replies, much appreciated.

There's no question that buying an American-made machine would be a "safer" investment. I haven't made the decision yet, and I always buy domestic if it makes sense.

The arguments about Chinese suppliers are spot-on. I know that from experience, as I said I have imported CNC router/mills. The only real protection you have is buying spares for *everything*, including the motion controller and dongle. The problem is that even after I include the costs of all the spares and factor in hours for troubleshooting and parts swapping, the imported machines are *still* only a fraction of the cost. Now - if you really DID get 20,000 hours from a domestic laser tube, then that might not be the case but from everything I've read it's more like 10,000 hours. I spoke with Epilog yesterday and they want $3300 USD exchange for a 75-watt laser. Using that metric and figuring in some labor to exchange tubes and re-align the mirrors, I'd still be far ahead (in dollars) to buy the imported machine and spares for everything.

The issues I didn't address are downtime, inconvenience and downright frustration. Those do have value, of course.

Again, thanks for all the replies. I'll consider them carefully.

--jim

Viktor Voroncov
06-09-2010, 3:27 AM
China is for hobby, brand - to make money

John Barton
06-20-2010, 7:12 AM
Mechanically inclined or not, when certain electronics pieces go belly up, there's little even a trained electronics tech can do. If the motherboard dies, it's not as simple as ordering a new one. The Chinese systems almost always use hardware dongles, change firmware revisions like they change their daily outfit, have poor quality control during manufacture, etc. The difference in firmware revisions can cause all sorts of issues as they don't stock older systems, they sell what they have on hand and then that's it. If your dongle doesn't work with the firmware on the replacement board, you're stuffed.

And when you can get replacement parts, they gouge you on the price, almost to the point of a new machine looking very attractive from a financial standpoint. Tubes arrive broken out of the box, or they last for years... it's a problem with their quality control, so you never know if you're going to get lucky, but you're rolling the dice. Even replacement tubes show up dead.

For the small investment, Chinese machines with glass tubes can be extremely useful... if you plan to use it in a production environment, you would be a real risk taker to try anything other than a reliable system with good support.

I agree with this post 100%. I live in China and bought a Chinese laser two years ago. This laser was bought on behalf of a factory I did work for. We used it a lot in the past two years and it had problems from the first month on.

During the times this machine was down we could not cut parts and our productivity suffered. Recently the factory moved it out to another location and so we were without a laser for three weeks. In those three weeks we found that we had grown very very dependent on the laser for a lot of our daily tasks.

Now I have just bought another one from the same factory. It appears to be much better than the old one. I have my fingers crossed. If something goes wrong then at least the people who built it are in the same country.

If I were in America and I needed to depend on the laser then I would NOT buy Chinese machine unless I was certain to be able to fix anything that could go wrong in short order.

John Barton
06-20-2010, 7:23 AM
China is for hobby, brand - to make money

I don't agree with this either.

In China there are thousands of companies running Chinese built lasers and they run them HARD, day in day out.

If you get one that works well and you do the proper care then you can run it in a production environment. The actual build is not that complicated.

I make money using my Chinese built laser. jbcases.com to see what we use it for.

That said if I had the ability to invest as much as I wanted to then I would buy a ULS laser in a heartbeat. (ULS because it's what we have in the US in our shop).

One of the factories who does pool cues bought three ULS lasers and they run them hard, hundreds of cues a week engraved on them as well as thousands of plastic and wood inlay parts cut. I think that for their purpose, which is the need to do very precise work the ULS software and the machine's precision is what they needed over any Chinese produced laser.

If someone could write a better driver than LaserCut which gets close to what ULS provides then Chinese lasers would be more competitive on the performance aspect in my opinion. But as for making money, there is plenty of money being made by people using Chinese lasers.

Viktor Voroncov
06-20-2010, 1:23 PM
I don't agree with this either.

In China there are thousands of companies running Chinese built lasers and they run them HARD, day in day out.

Key word HARD! I also saw a lot of companies in China who have 20 Chinese lasers. They work approximately 12-18 months and after owner just throw them to scrap. Cost of laser usually is returned in 2 months, equipment work 24 hours per day. One work is loaded from USB flash and is in production over 3 weeks.
Is it the same works in USA, or in Europe?

John Barton
06-20-2010, 7:42 PM
Key word HARD! I also saw a lot of companies in China who have 20 Chinese lasers. They work approximately 12-18 months and after owner just throw them to scrap. Cost of laser usually is returned in 2 months, equipment work 24 hours per day. One work is loaded from USB flash and is in production over 3 weeks.
Is it the same works in USA, or in Europe?

Exactly. If you have any piece of equipment and the cost of the equipment is paid for in a short time and you get another 5-10x the useful life out of it then you have made great money with it.

The Chinese lasers can be great workhorses, especially if they are set up for particular jobs and allowed to run just that job.

If I had a shop doing lots of different jobs and the laser was central to my business then I would NOT buy a Chinese laser UNLESS I had easy access to service and support as I could not afford the down time. In fact I have that shop but it's in China so I also have easy access to service and support. So I bought a Chinese laser.

Also I prefer the flexibility and easy use that the software drivers from ULS give me. I assume that those from Epiolog and other top brands are similar in function.

But it's just not so easy as to say "chinese laser for hobby and (name) brand for making money". It depends on what you want to do and your ability to get service and support.

Viktor Voroncov
06-21-2010, 2:41 AM
But I don't know many laser owners in USA/Europe who have same jobs as in China. People in Western countries have different, very often relatively small jobs.

Dan Hintz
06-21-2010, 7:15 AM
But I don't know many laser owners in USA/Europe who have same jobs as in China. People in Western countries have different, very often relatively small jobs.
This should be copied into the JDS thread as it is an integral theme to what's going on. More often than not, Chinese shops are running bulk orders of many thousands of the same item, so set up time for complicated designs is a very small portion of the project, amortized across a very large number of items. In the US, it's more often the opposite, where the job is a shorter run, so being able to set up the project quickly and correctly the first time is key.

John Barton
06-21-2010, 7:46 PM
But I don't know many laser owners in USA/Europe who have same jobs as in China. People in Western countries have different, very often relatively small jobs.

Of course. I think I addressed this several times. However you can see in the Rabbit threads that several people have said that they own Chinese lasers and run them 6 hours a day for years without problems.

I will tell you that we run one-off jobs quite a bit but we also have had some big jobs that have taken weeks to complete. Try making 500,000 stick on spots for pool tables.

Like I said, in America I WOULD NOT buy a Chinese laser unless I could be sure to be able to fix it myself and have plenty of support. I would also not buy a French made laser for this same reason.

I would buy a ULS or Epilog - I prefer ULS only because that's who we went with and they have been over the top great to work with from the factory to the local rep.

But people do need to consider $25,000 vs. $7000 in their decision. This is the price comparison between our ULS 660 and the price of a comparably sized Chinese laser. As the original poster said for that difference in price one can buy a lot of spare parts.

I run LOTS of small and different jobs on our Chinese laser. Almost all of the jobs we do are one-off type jobs as I do custom work. I am in China and support is an hour away so it's all good for me. The first Chinese laser I bought two years ago is still chugging along in it's weakened state cutting out parts by the hundreds each day. With a little TLC and some calibration the tech that was just here is confident he can bring it back to life. (it's not in my shop any longer).

John Barton
06-21-2010, 8:11 PM
Hi folks, 1st-time poster.

I'm a long-time CNC router/mill owner who primarily uses the machines for engineering prototypes. I'm considering both small and a large-format laser engravers/cutters for primarily the same purposes, although I'll want to be able to engrave my share of beads and trinkets as well.

My question is: How does the output quality of (for example) a Rabbit compare to that of a Western-built machine? I'll define quality as clarity of line and positional accuracy, to start. Speed is a factor as well, but for the moment I'm more interested in comparing the output quality.

For what it's worth, I own and operate imported CNC router/mills and once having learned the ropes don't have many complaints. Laser engravers are a new thing, though, so I'm trying to avoid making any expensive mistakes.

Thanks,
--jim

Hello Jim.

I should have answered this earlier.

We own a ULS 660 in the USA. I worked extensively with this machine for about a year. Two years ago for the shop in China I bought a Chinese machine similar to the Rabbit brand/build.

Here are my observations concerning output.

First the Z-axis bed was not perfectly flat and so that made any long cuts across the whole bed impossible. I am sure that a jig can be rigged up to eliminate this problem but such a jig would require manual leveling of the bed frequently. So the focus was never the same from corner to corner.

I just bought a new laser and the bed is fixed in height. I hated losing the z-axis and the capability to put taller things in the machine but the trade off is being able to cut larger parts with no focus fluctuation.

--------------------

Power fluctuations - our 80 Watt laser suddenly dropped 50% in cutting power in one day - we replaced the tube and got back about 25% - the dealer said and I quote, "it just happens when it's old". This on a laser under two year old with relatively light use compared to most Chinese users.

---------------------

Materials - our 80 watt laser had a lot of trouble with various materials such as certain plywoods, 1cm thick wood, certain leathers. Our new 100 watt machine cuts through all those like butter (for now).
-----------------------

Engraving - the 80 watt machine was not as precise as our ULS. You cannot (at least I could not figure out how) adjust the PPI as is possible with the ULS driver. PPI is similar to DPI (dots per inch) on a image/printer relationship. So for engraving you don't have the finer controls that the ULS driver allows. I am sure that people have figured out other ways to get the same results. On the 100 watt machine it doesn't engrave as nicely so we are finding we need to adjust our files to account for the bigger spot size.

--------------------------------------------

All in all the 80 watt machine was a decent machine and did almost all we asked of it that we needed. Comparatively though if you plan to do a lot of cutting then I would suggest the 100 watt machine and the fixed bed. If you plan to do more engraving then 60-80 watt might be more suitable. We definitely got more than our money's worth out it.

Software: They provide LaserCut which accepts dxf files. I don't know if Rabbit provides the Corel Plug in but our laser supplier did and that's what I use. They say that the results are better using the LaserCut instead of the Corel plug in but I haven't seen any difference. The dongle scares me but in two years ours never failed so I have nothing to say there.