Laser Stories Board

[Ya-Nvr-No]

Did some raster testing today in Hard Maple (I use samples from the big box stores)
K40 Tube
2-5 volts firing using a modified circuit like glenn provided, (the 5volt supply is dedicated, not from pokies, found it only provided 4 max during firing)
min 50 max 97
Pin20 / PWM2
100% power setting
my preference is the lower left, but at least now have a range to fine tune.
might be closer to 90"/minute for me, as id like a little more depth for this material.

[Ya-Nvr-No]

200"/min 90% power
46min 95max
3 passes step down of .03" each pass
3" diameter in Hard Maple
best i can measure on the outside edges is 0.171" deep (so my overall burn was more than i calculated for)
more testing till i find the sweet spots.
total time: I estimate at just over an hour total (I was so impressed, forgot to check timer)
Image was from an ArtCam file I created years ago and cut on my router as a 16" diameter and gift.

[ArtF]

excellent decoration!..


Ill release a version update soon , it has better depth control, smart rastering like the DSP's do
and many bug repairs, better connection tolerance for usb as well.

Art

[Ya-Nvr-No]

Here is a straight one pass burn.
Augment converted from a color .png file originally a huge tif file that I clipped an area from.
about 5" wide
80% 200"/min

[Ya-Nvr-No]

16" x 13" map

testing on clear acrylic,  mirrored image from back .008" deep

and then test burning thru three different foams, the black is 55mm thick.

[Joakim]

Very impressive!

Is it possible to cut that deep with the K40 in foam?
Always wanted to do that for making boxes with foam for tools or presents.

On my K80 I only have a focal depth of approx. 3-5mm, I think the lens has 2" focal lens.
But I have seen descriptions that the laser makes some kind of self focusing in deep cuts (in the cut gases) and it seems to work when cutting acrylic - it is possible to cut 10mm acrylic with little kerf, but 55mm foam...

I am in the process of making Auggie scripts to control the PWM #4 for current (15 - 100% maps 4 - 16 mA). Failed to get opto isolation to work with a PC817 or p521 opto-couplers as they are to slow to pass the 20kHz PWM signal correct.
Now uses direct PWM drive from PoKeys57CNC and had the same problems with to low voltage.

Having some problems getting script to do what I want it to do... (properly the learning curve...), but will soon have pictures too...  ;)

[ArtF]

J:

  I will make a release this week, dozens of bugs are fixed, Im just tracking down one more.. but will update afterwards..
Art

[Joakim]

Art:
Looking forward to the next update  :)
Have found a way around most of the found problems; Not sure if they are bugs or just me...
Just got the laser current control from DRO to PWM working and support for GCode S parameter (0 - 100). Yes.

Some time in the feature I would like to read the temperature of the cooling water with the Dallas DS18B20 sensor that is supported by the Pokeys (1-wire sensor). Will that be possible from Auggie script?

Joakim

[ArtF]

J:

Yes, it should be. I dont think Ive turned on 1-wire com, but I think it should work.

Just searching for one more bug before I release an update .. shouldnt be long.. ( hopefully. :) )

Art

[Ya-Nvr-No]

was asked if i could burn an old photo image, so I tired it on a piece of veneer, wiped a little fruit wood stain around most of it.

the string art gal was an image I found on the net, altered to a high contrast, then an augment invert, burning on matte board.

[Joakim]

Real nice - looks like the photo is printed onto the wood.

[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