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Bart Black
05-11-2012, 9:52 AM
I am considering getting a laser engraver, don’t know that much about them and have a few questions:



I need to be able to cut 0.125” and 0.25” finished plywood, what kind of power do I need to get a decent speed on this?
I also need to be able to cut 0.25” clear acrylic and maybe corian, what kind of power do I need to get a decent speed on this?
Would a nitro lacquer finished wood part be any problem to cut or engrave?
Can you engrave veneer plywood with good results?
I am used to using vetric s/w on a cnc router, is there equivalent s/w for lasers or do you just “print” directly from the application?
I see that the machine prices vary quite a bit for the same envelope / wattage. Conceptually they all seem to be made of the same parts. I’m sure there are different grades of parts used, is that the reason or is there something else to account for the difference; basically, why does epilog etal cost so much more than a wang-chung laser on ebay?

Dee Gallo
05-11-2012, 10:10 AM
Hi Bart,

Welcome to the Creek! You ask 6 seemingly innocent questions, which are actually about 10+ questions, but the answers are going to fill a book. You have found the right place, and I suggest you do what a lot of us have done which is start with post #1 and keep reading. You will find the simple and complicated answers you seek. There are a lot of variables to color every topic you've brought up - there is no ONE answer.

Sorry to sound so unhelpful, but if all you want is answers to your questions, here are some:
1. a lot
2. a lot
3. no
4. yes
5. yes
6. because that's what they charge

But seriously, you will find a lot of help here. Try the "advanced search" at the top right of this page, typing in your topic to get to related threads.

Good luck, dee

George Carlson
05-11-2012, 11:13 AM
I have a Chinese Redsail machine with a 60W tube. It cuts most 1/4" plywood with ease, but some materials are tougher than others. It cuts acrylic up to 3/8" on a single pass. I usually spray a light coat of lacquer on bare wood to make it easier to clean soot off the finished surface. Nitro lacquer seems to act as an accellerent. I spray a coat of lacquer on stainless steel parts and then engrave them with the laser. It makes a nice brown color and works well for putting part numbers on items I've machined. It doesn't work on bare aluminum :-( .
For the most part, Chinese machines use a controller made by Leetro. The most common controller is the MPC6515. The Leetro controllers use a program called LaserCut 5.3 (there are some private label version such as EasyCut for the Redsail lasers). This is not a bad piece of software, but it is not as sophisticated as the some in the US.
Chinese machines use glass tube DC excited lasers. Most US companies use Metal tube RF excited lasers. The RF lasers have much finer control characteristics, and are supposed to last longer. The glass tubes are less than 1/10 the price of the metal tubes (which can be rebuilt). It depends how you are planning to use it. I'm just a hobbyist, so the US machines are out of touch for me. The Redsail M900 I have works great I'm really glad I bought it.
BTW, Make sure the Chinese laser has FDA approval. If they cannot provide you with an FDA accession number, stay away from them. You can not bring a laser into the US that has not been FDA approved (except for very special reasons).

Larry Bratton
05-11-2012, 12:08 PM
I am considering getting a laser engraver, don’t know that much about them and have a few questions:



I need to be able to cut 0.125” and 0.25” finished plywood, what kind of power do I need to get a decent speed on this?
I also need to be able to cut 0.25” clear acrylic and maybe corian, what kind of power do I need to get a decent speed on this?
Would a nitro lacquer finished wood part be any problem to cut or engrave?
Can you engrave veneer plywood with good results?
I am used to using vetric s/w on a cnc router, is there equivalent s/w for lasers or do you just “print” directly from the application?
I see that the machine prices vary quite a bit for the same envelope / wattage. Conceptually they all seem to be made of the same parts. I’m sure there are different grades of parts used, is that the reason or is there something else to account for the difference; basically, why does epilog etal cost so much more than a wang-chung laser on ebay?


Bart,
1 & 2-I have an American made Epilog EXT machine with a air cooled tube, rated somewhere between 40 and 45 watts. I cut 1/4" acrylic and 1/4" plywood. 1/4" acrylic is relatively slow. For example, my table size is 36" x 24" and cut 4 designs out of a laser table size pc of 1/4" cast,brown acrylic. The design was 11" x 16" with an outside and an inside cut. It takes approximately 5.25 minutes per design or 21 minutes for all 4. 1/8" is faster by better than 1/2 the time. The 1/4" is cut at 6 speed,100 power and 5000 frequency (if that means anything to you). I can manage to get through 1/4" Corian but not the standard 1/2" and the 1/4" is slower than 1/4 acrylic.
3. Not familiar with that.
4. Would probably depend on the quality of the plywood.
5. CNC router software is different from laser software. My laser uses a factory supplied print driver and I use Corel Draw X4 for design creation and sending to the laser. So, it's a relatively simple printing operation with no toolpaths unlike CNC work.
6. It depends on what your planning to do..serious work or hobby stuff. Technical support is very important as well as support for parts etc. Epilog's technical support is superb. My machine is 5 years old and has performed worderfully and I can call them right now and get the same technical support as I would if it was a new machine. They ship parts overnight from Colorado, not from China and they speak excellant English.

Bart Black
05-11-2012, 3:50 PM
Larry,

So do yo know what speed you are cutting those designs at or is that not revealed to you by your s/w?

Michael Hunter
05-11-2012, 5:31 PM
For cutting 1/4 wood (especially ply) it is good to have plenty of power available. Larry manages with 45W, but 60 to 80W will be a bit quicker and will cut slightly thicker stuff too.
(Note that "quicker" is not fast - my 60W is set to run fairly slowly on 1/8"-3mm ply).
I would certainly want a highish power machine for cutting corian.

On the pricing, there are three levels of machine -

At the expensive end there are the USA and European made RF (metal) tubed machines.
These can be expected to work 100% from day one, be pretty reliable and have excellent backup from the manufacturers.

Middle range is Chinese made machines imported in bulk.
The good re-sellers know the machines well, sort out any QA problems before delivering to you and provide good backup with advice and parts.
Generally, these will have DC excited glass laser tubes which are "cheap", but can't be expected to last very long (6 months to 2 years, depending on usage and luck).
Glass tubes are not as easily controlled as the metal RF tubes, so these machines *might* not achieve the same engraving quality as the USA-made ones.

Cheapest is direct personal import from China.
Read the threads here and you will see that delivery and QA problems abound.
If you have the knowledge and tenacity to sort the machine out yourself, then you got a bargain.

Larry Bratton
05-11-2012, 7:16 PM
Larry,

So do yo know what speed you are cutting those designs at or is that not revealed to you by your s/w?

The speed,power and frequency are set in the print driver as part of the printing process. The settings are determined based on the material your cutting or engraving. Epilog supplies recommended settings in the machine manual, but they are just recommendations and some experimentation on your part will fine tune your settings to the machine.

Rich Harman
05-11-2012, 7:38 PM
Read the threads here and you will see that delivery and QA problems abound.
If you have the knowledge and tenacity to sort the machine out yourself, then you got a bargain.

I agree completely except for the bit about delivery problems. I don't recall anyone having a problem getting their machine delivered. The process for importing and arranging the shipping is certainly more involved but completely manageable.

The QA bit is frustrating. Your last sentence is spot on.

Bart Black
05-11-2012, 10:13 PM
I have seen quite a few bad stories on the "direct import" route, then again the bad stories are what get people riled up enough to post. There does seem to be a lot of those stories out there though, seems pretty risky.

So if I went with a 100w co2 glass tube machine for cutting power, could I expect to have decent controllability for engraving?