View Full Version : Some specific laser questions

Richard Link
07-28-2011, 7:19 PM
What a great forum. I've really enjoyed reading a whole lot of laser posts over the past few weeks and may have learned a bit. I have a couple of very specific questions, though, that haven't been directly addressed (as far as I can tell). I'm in the usual position of considering both US made and Chinese made lasers. Primary application would but cutting 1/8" baltic birch, wood engraving, engraving some glass panels for cabinet doors and perhaps some rotary objects (pens). Not a high volume operation. I'll spare everyone another series of questions comparing brands, customers service, etc. Certainly lots of great posts about that already.

1. In comparing say an 80 watt Rabbit system (say 80-1290) against a 50 watt epilog with "radiance optics":

a. Is the quality of the engraving going to be better due to a smaller spot size or some other magic with "radiance optics" or is this not the case? Is this noticeable or just a marketing issue?

b. Is the higher powered Chinese laser measured on an absolute scale such that a 50W Chinese laser is the same power as a 50W epilog? Is there some salesmanship going on here that would mean that a 75W epilog machine would be significantly more powerful than an 80W Chinese machine? I know that some have commented that the higher powered tubes produce a "poorer beam quality" or "are more suited to cutting as opposed to engraving." Even if the tube produced the same power, is there something about how the beam is diverted to the substrate on the Chinese machines that makes a 50W epilog more effective than an 80W Rabbit?

2. Assuming that I can stomach the potential service and support issues with a medium range Chinese laser (ie a $8500 rabbit 80-1290), am I likely to see a noticeably poorer quality final engraving or cutting result under the best of circumstances?



Dan Hintz
07-28-2011, 8:33 PM
1a) For the type of substrates you want to work with, I don't think you'd notice the difference in engraving resolution as you won't be maxing out the system.

1b) You can be pretty sure the 80W Chinese tube is, at best, 80W. With the RF tubes, a 50W is typically 10-25% higher, but will settle back some after a few months of use. A 75W RF tube (Epilog) will more than likely be much stronger than an 80W glass tube.

2) See above. The higher-output tubes will not have as high a quality of beam as the lower tubes. If engraving is all you wish to do, I wouldn't go any higher than a 60W... anything more will be wasted, and as it is you'll be running at less than full power at full speed.

Frank Corker
07-28-2011, 8:45 PM
Wow Richard, opening a can of worms with those questions, it will really take a reply from someone who has both types of machines. I suspect Rodney Gold will be the man who might be able to answer your questions as he has recently purchased a few. With some of these 80 watt machines they are water cooled and rely on a very different type of knowledge of use, the Epilog are sealed air cooled units and are pretty much self protecting. As regards to how they measure the power scale, I'm not too sure on that either, I do know that when I bought my 45 watt laser that was the minimum that it was putting out. The radiance optics are pretty brilliant regarding quality.

Which is pretty much the crux of the problem you have, do you buy a machine that has a minimal amount of cash layout or one that is pretty hefty from the outset. If you go on previous posts by members, the Chinese type machines have some horror stories to weed your way through, there seems to be a shortage of solid advice because each machine appears to be different. I was fortunate enough to be in a position to buy my machine and I have never regretted not looked at the Chinese ones available despite them being plentiful, but I do know that if I have a problem, a quick call and the aftersales from Epilog are second to none. I have heard exactly the opposite from the Chinese laser purchasers, poor aftersales, poor manuals and poor build.

If you are a hands on type of guy who loves a really good challenge without the help of users of more sophisticated machines, then maybe the Chinese laser is for you. If you want a good reliable build with a good backup service, then look at a more reputable company which is home grown. Consider when you do, the depth the machine can work to, some of the Chinese lasers can only hold very small items, my Epilog can work a piece 11" deep on an 18x24" bed. I think if you go for the Chinese, you will have more than just potential service and support issues, you will have a very frustrating uphill struggle to achieve greatness. My opinion though, not everyones.

Richard Rumancik
07-28-2011, 10:27 PM
So far on this forum, lasers seem to have been placed into two categories - those made in USA/Europe and those made in China. But after Rodne's post I think there is a third category - those made by Liaocheng Shenhui Laser. Now maybe there are other Chinese lasers that can go into this category, but so far I don't know of them.

So when someone says "Chinese laser" I am not quite sure exactly what they are visualizing, because to me there are the Shenhui lasers and the rest of the Chinese lasers. Rodne has given me enough confidence to think that the Shenhui machines are respectable laser systems, although I admit they seems to have a few glitches. I realize some people have bought other Chinese brands and have made them work in one way or another, but I don't think they are quite ready for prime-time yet. They seem more appropriate for people who are DIYers, have probably owned a laser before, and have substantial mechanical and electronic skills as well as plenty of time to address the shortcomings. Maybe some of those manufacturers will get there, but at the moment they don't seem to be on par with Shenhui, from what I have read.

I am not in the market for a laser at the moment but if I was buying Chinese I would probably look very seriously at the Shenhui. I don't know how the price compares to the Rabbit. After 6 months perhaps Rodne will have a better idea of the overall quality and reliability but from what he has reported so far he seems very satisfied.

Richard Link
07-28-2011, 10:28 PM
Thanks guys for the input. Just what I needed. Thanks particularly for highlighting the differences between the RF tubes and glass tubes. Now that makes sense.

I was trying to avoid getting into a Chinese laser vs Epilog/ULS argument just because I'm sure you all have been down that path too many times for comfort in the forum. Like many others, I'm struggling with the usual conflict of deciding between buying a large format Chinese laser now (RL-6090), a smaller format entry-level Epilog (Zing 24) or Universal (Versalaser 3.5) soon or holding out to save up for a larger, more feature rich US laser in 6 months or so (ie a Helix). The ULS versions seem to be priced about 1.5K over the similarly sized and outfitted Epilogs. The Helix really seems to be the perfect choice but I'm having trouble really getting my mind around whether the extra 5 - 6K is really justified when compared to the Zing 24. Perhaps you might have some input on that being a Helix owner, Frank.

Frankly, I'd love to go the used route but the issues of transport and the status of the laser tube in these used machines have made me nervous. Perhaps a really good opportunity will show up locally at some point and make the decision easy.


Richard Link
07-28-2011, 10:33 PM

I'm not familiar with Shenhui beyond a few posts. I'll have a look. The Rabbit came up primarily because there is a US distributor here in Texas, and that seemed to be a favorable factor. Several posters have apparantly had a good experience with him. I guess you are right that we shouldn't be referring to these as "Chinese lasers" since there is a large range in price and (I assume) quality. The Rabbit systems I was looking at seem to run in the $8K range for a 2 x 3 foot cutting area, 60 - 80W, glass tubed machine with steppers. I realize there is another class of much cheaper instrument from China (ebay, etc) but don't think I'm going to go that route.


Dee Gallo
07-28-2011, 10:58 PM
Richard, I think you can approach your research by remembering there are big and small differences between the various American made lasers, and the same applies to Chinese made lasers. Look for the features you need or want, consider how much tech support you will need or want, buy what you can afford when you can afford it including the exhaust system which is important.

I owned one of the early Chinese lasers which I sold unused to someone who was into the mechanical aspect since it looked like a Rube Goldberg device to me when I opened it up. I was afraid to start it up. I went with another Epilog afterwards because I am NOT a techie and wanted the support system Epilog is famous for. But things have changed dramatically in the past 5 years, although Epilog's service is still #1 in my book.

that's my two cents, dee

Rodne Gold
07-29-2011, 12:28 AM
It all boils down to energy density which is a function of beam diameter , quality and focus length of the lens. The size of a spot is what counts , 50w in a spot 1/2 the size of 80w will be more effective. It actually gets a lot more complex than that in answering point 1 and 2 , but the essence of my answer is this:
Can you accept slightly worse quality of engraving and a shorter tube life for 1/10th of the cost?
We are not talking huge differences here in terms of quality , if you use the right chinese tube , you may get the same or perhaps 1/2 the tube life of a conventional tube .. i dont have enough experience with the good glass tubes to tell.
$8500 is quite high , a 80w laser 1200 x 800 laser with the best quality tube (reci) , spare tube and enough spares to just about build anther machine should cost about $5500 Fob China, however if you want local support , then it might be worthwhile paying the extra. So far I have had exceptional support from China...but I don't need handholding when it comes to lasers. Check out my posts , chinese lasers ... they are here and my post Despatches from china.

Mike Null
07-29-2011, 12:30 AM
While I can understand the interest in Chinese built machines I would not consider one for myself. I am a one man business and need a machine that I can depend on day after day. If I need parts I want them to be immediately available.

I am yet to be convinced that Chinese is cheaper in the long run. I'm sure Rodney will take the other position but he has several machines and staff to fall back on.

Rodne Gold
07-29-2011, 1:13 AM
Mike , Not quite sure what will fail on these machines , but spares are dirt cheap so you can afford a raft load of them and after having my machines for a while , it becomes apparent they are fairly simple , it remains to be seen what their longevity will be , but as you note , I have many machines and am fairly commercial so I treat the machines more as production tools than capital investments and at their prices , If I get a year or 2 or hard use from them they more than cover their costs and I can afford another and just dump em..you also have to take into account that I am in South Africa , so have no access to the type of support that you have in the US , makes little difference to me whether spares etc come from USA or china or Germany...
The main issue isnt really whether they are cheaper in the long run , which I think they would certianly be , but its affordability. The guy wanting to start out lasering cannot afford the $30+k that a 1200 x 800 x 80w mainstream would cost , but can see their way to $6k or so , if it doesnt work out , they dont lose the farm and if it really takes off , they can maybe swing for a mainstream if they find reliability a problem. A lot depends on your business model and willingness to compromise ...
I have always said, and repeat, that if you want to just press the button and have it work and are a total newby to both lasering and have no existing business , it might be better to buy a local mainstream.

Craig Matheny
07-29-2011, 2:13 PM
Richard I was just at my Epilog reps store yesterday and asked about the zing and the Helix / Mini we talked about how there is a zing that cuts the same wood I do at 100% speed (lets not go down the test thing again it was not the best of my post) what I was told is the zing speeds are about 1/5th that of the mini / Helix. So at some point speed becomes the biggest difference between the two machines a Helix will out engrave a zing all day but vector the time will be the same in reality but different on the display (hope you followed that).