Small Parts Falling Through Grid

[Ed Maloney]

Hello there folks. I cut a good amount of small items that tend to fall through or get stuck in the grid. This is a real pain since I have to remove the grid and gather up the parts and then re-focus again. Picking the many stuck items out of the grid is a big time waster too. We're talking 1/8" Birch plywood material.

So - I am thinking about building a box to capture the small pieces. Finally here are the questions:

1 - How deep should the box be so the laser doesn't cut through the bottom?
2 - Should I make the bottom with a screen so it will vent?
3 - Any alternate ideas?

Ed

[Mike Null]

I'd be more inclined to build a tray rather than a box. Air flow under the cutting grid is critical. You'll pretty much have to judge for yourself the depth as that will vary with power and wattage.

[vic casware]

I'm surprised it doesn't have the slide out tray that the Helix has
it's almost the same machine.
The fusion is a laugh, after you take the grid table out with a forklift
or helicopter or 2x 7 ft wrestlers you have to unscrew the side
then tip it up and shake all the parts out, and i'm serious it's almost a 2 man job

[Kev Williams]

3 of the 4 C02 lasers I work with have solid aluminum tables, and I get nearly the same results just cutting directly on the aluminum as I do on the honeycomb table in the Triumph. And with the grid being gucked up with acrylic and wood soot, sometimes I prefer cutting on the aluminum. In my experience, no airflow under the wood is needed for the purpose of cutting, you just need to be able to evacuate the smoke. If you cover the grid, leave SOME space for the blower air to move.

Find a piece of aluminum, ANY aluminum, and do some test cuts, you may be surprised--

The only drawback, the table will collect the sap from the cut. But some DNA or turpenine and a paper towel and it wipes right off in seconds. Much less time than digging stuck pieces from the grid!

[Patrick Gardner]

I cut a lot of very tiny letters and have found the best way to avoid having the smaller parts drop down into my honeycomb is to use a piece of aluminum window screening on top of the bed. Works perfectly.

[Ed Maloney]

Sweet! I was thinking the same thing. So the screen doesn't get cut?

[Kev Williams]

good idea on the window screen, I may try that on the Triumph!

--as long as you're using aluminum screen it should be fine :)

[Ian Stewart-Koster]

I've used the mosquito netting window screen also- quite a bit- and found after 4 or 5 uses, you need a fresh piece.

[Ed Maloney]

Hi folks and thanks for the help. Here is an update. I used this and it worked great and saved me much time. Thinking that the black color would reduce the the back flash it wasn't bad but with using the grid it was less. So next step is to elevate the wood a little bit and see how that goes. I will keep everyone updated.

386888

[Bill George]

Ed, they also make a aluminum grid for return air registers that are in the 2x2 ft or 2x4 ft drop in panel ceilings. The grid is maybe 1/4 or 1/2 inch squares and not very thick grid walls. Since I am no longer active in the trade I can not tell you what to ask for or where to buy?

[Scott Marquez]

Ed, they also make a aluminum grid for return air registers that are in the 2x2 ft or 2x4 ft drop in panel ceilings. The grid is maybe 1/4 or 1/2 inch squares and not very thick grid walls. Since I am no longer active in the trade I can not tell you what to ask for or where to buy?
This just reminded me that I picked up a piece of 1/2” x 1/2” acrylic grid from Home Depot lighting department, a few years ago. You could lay your screen on it and it would allow airflow and catch your small parts.
Scott

[Ed Maloney]

The resolution on my recent question about small parts.

The screen idea is the key so parts won't fall through the grid. I first tried to lay the wood directly on top of the screen but didn't like that the underside of the pieces get mucked up. Raised the wood up 1/8" using spacers resulted in some finished parts which fell down to the screen getting stray laser cuts since they fell into the path of the next piece being cut. Built a tray with 1" high walls and placed the screen under it and the wood on top of the tray. Similar thing happened as the 1/8" height but instead of stray cut it blackened a good amount of the already cut parts since the beam was re-hitting them out of focus. I noted that the "crumb tray" was 2 inches so I made a tray with 2" walls. That was the combo that worked.

Thanks for all the suggestions and help.