Polywood , Auggie and sugar

[BobbyW]

Hello everyone .
As i say in some post , engraving on polywood it is realy tricky.
Why that ... couple of things i notice during time .
Well , ploywood is very different , i mean what you engrave today on same type
of wood will dont work tomorrow with the same settings.
I notice wood react so different on different moisture .
I keep my , on a chamber where the RH is strict controlled (is tobbaco chamber) but even like that
will dont work all time the same . Maybe you need couple of try until you got a good ressult.
Trying to find a good sollution , i mean something "stable" that didn't work. Depend to much where the wood grow ,
wet or dry place ,chemical soil components and many other things can made it " non standard type"
So .. looking when my wife made kookies i realise the sugar keep it in high temperature
will change the collor in " linear " way , or... almost .
I say to made a test , i put some sugar in boiling wather and after cool down i apply on polywood
surface with a brush . I clean with " absorbant paper " i dont know the word in english
and i let it dry for 30 min.
And i start to engrave some old photo.
Well the result wasn't to bad , because the photo was made with my phone
from a " paper photo " and after engraved.
And i made two test on different type of polywood , that normaly need 2 totaly
different power , speed ...
They come almost the same .
Now i let a piece of polywood on very dry place and i will made a test with sugar
after is very dry to see if will be any difference . I notice when the polywood is very dry
to get the black level the laser will go to deep. Make sense anyway.
I will post here soon the polywood will be dry.
.....edit later...
The white dots on small picture are normal, the picture was made when snowing agressive .
Thanks
Bobby

[ArtF]

Very nice.. Thanks for the tip..

[BobbyW]

Thanks Art.
Well , i test today and the polywood was realy realy dry.
Usualy in that situation the "black"level will never come visible.
Even you increase the power or decrease speed , laser will simply goo deep cut and will be like 30% maximum
level of dark. A simple example is in picture below. The cut is very low level, so
in that situation , is impossible to get dark parts as should be .
So i apply the sugar on surface and i made a test . Dimension is 215x279mm.
I let 30min to dry and i start engraving . Take 28 min on that photo to finish.
Usualy i made the photo grayscale before import in Auggie with color limit
at 100.I put the pic below. I use paint.net , is free and so many extensions.
In Auggie i use linear contrast and always limit at 100 , on screen look little creepy
but the result not.
I put the pic below with result after sugar apply .
100ml boiling wather , 2 spoon of sugar let cool down and apply with a brush.
Thanks
Bobby

[ArtF]

Thats REALLY good. I still havent got around to trying that as yet, but it sounds
like a great technique..

Art

[BobbyW]

Thats REALLY good. I still havent got around to trying that as yet, but it sounds
like a great technique..

Art

Well i always assume , doesn't matte how you system is , the PWM will
never exceed 100. That why i limit all colors to 100 and after i transform in grayscale pic.
Also in Auggie i always limit white to 178 and black to 77 , i assume like
that will be in PWM full range.
Even like that speed is essential. As example in 2 pic below .
The right one is almost perfect (power was little low) but doesn't matter because i know
was my fault and the speed was 4000. Made the pic in 23min .
The left one i was increase the power a little and speed to 8000 and half time at engrave.
But as you can see , timing was tealy short for each pixel and didn't have
time to reach full black level on wood.
Both was with sugar , but was different type of wood , from indonesia "albasia".
I try before on that wood but didn't work so well. Now with sugar the result are different of course.
Still should be beautiful if you have time in " one day ' to made the AUGS window more bigger
or possibility to be resized . 
I put the pic below
Thanks
Bobby

[ArtF]

Next Time Im in there I will stretch it ...

Art

[BobbyW]

Next Time Im in there I will stretch it ...

Art

Thanks . I wait for it . ;D
Also i figure out other thing . I dont know if is a bug , or like that should be.
If i edit any pic and i erase background is some place's or total
and i save it .JPG and load in AUGS is ok . The background zone is white like
" no pixel level information " .
If i save it as .BMP and load in AUGS the background will become black .
That is normal ? Why the difference between 2 formats?
I mean the AUGS dont use the same " pixel read " altgorithm ?
Thanks.
Bobby

[ArtF]

Its possible the jpg has a transparency color defined as black, where the bitmap simply defines black as black.

Art

[BobbyW]

Other sugar test , on different material with maxim speed .
The low black lever dont apeear anymore , because the beam dont have time to burn deep
but the job was done in 6min .
Of course the result is not the same as at low speed , when the black turn to black.
I notice , to low speed is bad , to high is also bad , so  i think for any machine
need a unique config. What work for me will dont work for others
because are to many discutable factors on that.
thanks
Bobby