Laser Stories Board

[Ya-Nvr-No]

Thank You I'm having fun

and yes it is wood, thin sheets that are peeled off a log.


here is a web site that explains a little
http://www.decospan.com/us/Wood_veneer/What_is_veneer/

[Ya-Nvr-No]

Took an image found on the net of a high res tiger, burnt walnut one pass 2" square, 0.060" deep
55% @ 120"/min

[hhouben]

I just tried to make a double wheel in one piece.
Its a Gear for a small model train. The small gear wheel part is Module 0.4, the larger part Module 0.3.
It was lasered in two stages to keep focus sharp enough. But the acrylics (6mm) is too brittle. The gears break after short time of running. :(
Module 0.3 is at the edge of what is feasible with my laser. The spaces between teeth are beam size...
Anyone tried to make similar pieces?  Next time I will try Delrin. Hope this will do better.

I already made several single gearwheels Module 0.5, which is quite easy. They are stable enough even wth acrylics. I have them running for weeks as a replacement in a toy train for my grandson. No problems until now.

[Joakim]

hhouben:
Impressive that you can make that small gears!

Have you tried annealing the acrylic after laser cut.

Laser cutting acrylic generates a lot of stress (forces) on the cutting edges - trying to glue or wipe the edges with alcohol or acetone makes it crack as crazy. I tried annealing the acrylic at 45-60 min at 80-90 degrees (3mm acrylic) and that did the trick, it was now possible to glue without cracking.

Joakim

[ArtF]

That IS impressive. Ill have to try some small ones..

Art

[hhouben]

No, I did not try annealing the gears. Maybe you are right and they will become more stable. I?ll try.
But mainly its an issue of acrylics.  For durable gears I shall need Delrin and perhaps a lens with longer focus (70mm or more) in order to getting a straight beam throughout the whole sheet.
Until now I use a 50mm focus, so the beam widens after 1.5 mm - too much for good gears...

[Ya-Nvr-No]

Did some testing today on acrylic cutting, the material is 0.473" thick. Photo shows the results of Feed 2"/min @ 100% power, no air assist (as it seems to cause a cloudy pattern at the top of burn) But the slower I go the clearer the burn. A feed of 1" was much better. Love the samples I picked up at the recent NBM sign show for my testing.

Nice to have a machine at 1/4 the cost or less than the ones commercially sold. And lasers sure beats cleaning up wood chips and dust around the shop from rotary cutters. ;D

[BobL]

Ya-Nvr-No;

I agree, nice to build a table at 1/4 of it's original cost.. Congratz .. I'm still at my unit getting things ready, it is now under Pokeys57CNC control from the older 56E and appears to work well. Limit switches are installed for X.Y, not sure where to put any for my Z though? With my newer computer 2.6Ghz, tested the network going back to "0" in Auggie, got the rough and jittery sound in my motor moves again, so reverted settings back to  "1" in Auggie to fix the problem, this isn't a problem, I was just testing performance. Anyhow back at it so I can get that much closer to cutting things. I'll post pictures soon...

Cheers
Bob