[SRT Mike]

I am interested in purchasing a laser - I keep going back and forth on what power I need/want. Here's what it will be used for (hopefully)

1) Cutting acrylic. Mostly thin (1/8") but up to 1/4" or even 1/2" would be nice.

2) Marking aluminum. I machine electronics housings that I get anodized and I want to be able to mark the company name on them, and label buttons, etc. I want it to be clearly readable.

3) Cutting gaskets. I am not sure exactly what material this would be - some sort of very thin rubber sheet.

4) Cut foam. I would like to be able to cut polyethylene and polyurethane foam up to 1 to 2" thick (ideally). I'd need to be able to do at least 1". I want to make short run foam box inserts for packaging and the volume doesn't justify a roll die being made, so I think laser will do it?


That's what I need to do. What it would be NICE to do - but not required - would be

-Cut acrylic up to 1.25" thick
-Mark acrylic in 1/8 or 1/4" thickness (for plaques and the like)
-Mark glass (wine bottles for souveniers, etc)


Some folks say a higher power last will allow things like thicker acrylic to be cut - which I am sure is true. Some say that higher power is worse for marking, which I am not sure on. I certainly would not want to have a unit that does a shotty job of one of my requirements, just so that it fills one of my "nice to have" list.

I'm thinking around 80W would be suitable? Any feedback from those in the know?

[COtwo]

The 80W system you mentioned will surely do what you need. I have 2-25W and 1-35W and these will also do all you have listed with the exception of the 1+' acrylic. I would look for the biggest "bed" / table you could find also. Keep us informed.


Bruce

[miljnor]

Thats a good question that I have wondered about.

Alot of people in the industry say that the 80w lasers are not good for engraving, does anyone know why this is so???

[COtwo]

A lot of the "engraving / cutting" depends on the focal lenght of the lense. For the finest engraving I believe the 1.5" focal length gives the best detail.
I have heard the 4" lense works better for cutting. If you look at an hour glass shape and imagine that as being the "beam" of the laser you can see the convergenge and divergence point as being the focal point of the object being lasered. If you are going to cut something thick you should try to focus somewhere near to the center of what's being cut vs. the top most surface.

There are many engravers out here using 100W machines to engrave with, so I know an 80W machine will also work. They are a lot of fun too!

[SRT Mike]

At Eastec last year the guy selling Epilog lasers was showing off the rotary attachment and he had a Mag flashlight that was originally purple anodized and it had been marked up with a flame-like effect. The marked areas were a pale puple and the rest was a dark purple.

While it did look cool, I was surprised and a little dismayed at the result. I thought it should blast away the anodize and leave silver underneath, but he claimed marking anodized Al does not work like that.

I'd like to be able to anodize something in red, blue, black or whatever - and mark it to where the marked areas are silver (bare Al). I believe I could also either turn down the laser power or move it quicker to lighten the anodize instead of totally removing it. If it's not possible to lower power and lighten rather than blast it away, I'd rather just have enough power to blast it away rather than having a weak laser that can only lighten it.

Make sense?

Any comments on laser power in relation to marking Al?

[miljnor]

He is full of S#$t!

A laser of the appropriate power level (20w should be sufficient) will completely remove the anodized surface to a whitish almost sand blasted look.

It was probably a really low power level he had it turned down too. But that leads me to believe you could get a gray scale of color with a lower power level which would look way Bit#$en!

edit: anything that could be said on a national news channel or radio talk show, shouldn't really be edited on a web sight! Bogus!

[COtwo]

Ditto!!!! You can completely obliterate or go for a lighter contrast!~your choice. I have done many a Mag Lite, also powdercoated metals are good for this too, although some powdercoated "stuff" is likely to require 2 passes. (At least w/my 25W)


Bruce

[KTP]

I just waved a piece of black annodized aluminum under a focused 10 watt Synrad J48-1 (doing around 16 watts though) and produced these very white marks:

[Laser Guy]

This was marked by me with a 30W Laser at 33% power. The upload images not so great but the actual part came out fantastic.

[ViperTX]

So, which lasers do you guys have?

[Laser Guy]

LaserPro Explorer

[COtwo]

I have 2 - LMI 25 watt, 1 - Epilog TT 35 watt. 11 X 30" bed on the LMI's
12 X 24" on the Epi.

[KTP]

Laser guy:

What type of lens system did you use to get those marks? The detail is quite fine...am wondering what your spot size is? Do you know the F.L. of the lens and your spot size? Does your system have beam expanding optics?

[Laser Guy]

KTP
You're looking at it. That is a lens for a laser engraver and it is my own product. 2.0 F.L. and .005 spot size. Using a beam expander for decreased spot size and higher power density is not necessary for and anodized Alum. The key is to use a feeler gauge to properly zero out the lens. I've been doing just that for over a decade and there is no substitute for properly focused lens.

[KTP]

Oh, I didn't realize you were manufacturing the lens holders for Epilog...nice!

So is the lens plano convex or is it meniscus? I don't have any meniscus lenses in my collection...are they required to get that small (.005") spot size?

[1eyedguy]

i would go with a high powered laser , so engraving and cutting of thin non-metalics are not your only options