mini laser engraver, again

[LCHIEN]

I've had this thing since 2017 and posted about it before,
https://www.sawdustzone.org/forum/di...laser-engraver
I had a hankering to fire it up to engrave some chopsticks for gag gifts.

I had to make some improvements, lining up items was always tough especially sine chopsticks are skinny any misalignment makes the text run off.
So I made this thin bed with Centimeter marking grid on it and a pair of pegs to align it with the platform. Fastened with double stick taple



Then I added a removable alignment bar which registers to the holes on the left. The helps me line up squarely small blocks and longer items.



using the alignment block




Dust collection.

I noted in my 2021 that the laser carving was putting very fine particulate in the air in my shop.
My dylos Air quality monitor indicated low 5 u particles but 10s of thousands of 1 u particles. And the smoke was contaminating the workpiece.

According to we resources laser engraving makes fine aerosols of 0.1 u in size, not the greatest stuff to breathe, basically its like tobacco smoke.

I made a small cabinet and used a convenient cabin air filter 9x9 approx and a 4" AC powered chassis fan to suck this up, I just ordered a HEPA filter (99.97% at 0.3u ) instead of the plain pleated one.



(will complete later - getting upload errors from site.)

So far with the pleated filter I was running 4-5000 particles, but when I turned on the big delta shop filter It was reduced a bit
I hope the HEPA filter helps a lot or else I'm gonna have to do it outdoors.

[Jim Frye]

I'd be tempted to place the shopvac hose right next to the workpiece.

[LCHIEN]

Unless the shopvac can filter stuff below 1 micron, you are just blowing it back into the shop at high velocity.

[Jim Frye]

I use CleanStream HEPA filters in my ShopVac. Supposedly rated at 0.3 microns.

[LCHIEN]

OK so here's the filter box I made



The HEPA filter to fit is coming tomorrow, I will see if it reduces the airborne particulate.
At the time I made the box, I randomly chose a 1997-2001 Honda CRX cabin filter from eBay. I didn't know any better because the one I got back then is not a HEPA.

[LCHIEN]

got the new HEPA filter today and wow what a difference.
The old pleated filter I would get 5000+ particulate count with just it and if I turned on the shop air filter MERV -something it dropped to about sub 3000.
I went into the shop after a few hours of non activity and the Dylos was reading 149 counts of 1 micron particles
I put the new HEPA filter on my filter box with no shop air filter on and ran several items to engrave and the Dylos stayed at 149-151 the whole time (where the old filter would have hit 5000). So its very effective on smoke sized particles as claimed.

New filter. Nice Blue! Very effective!