Is there a way to put something under the piece we are cutting to "catch" small pieces?


#1

When I cut very small parts on the laser at my maker space, the small parts sometimes fall through the honeycomb mesh under the part I am cutting.

I’ve often thought about putting a “sacrificial” piece underneath the piece I’m cutting. Something that will not be cut all the way through, so will stay rigid. It would prevent small pieces from falling through.

Has anyone ever done this? Are there problems with heat dissipation? Are there materials that are preferable to use as the “sacrificial” material?


Laser Bed Cookie Sheet?
#2

Could you use a piece of aluminum foil, wrap the honeycomb with it? I don’t think the Glowforge will cut it…probably. And it shouldn’t have enough thermal mass to draw away much heat.


#3

Good suggestion. I’ll have to try it.

I’m just wondering if anyone is already doing this, and if so, what are they using.


#4

Crumb tray seems to slide out pretty easy to me.


#5

Yes, I can retrieve the small parts from the crumb tray.

But if I want those parts to stay in place relative to the other small parts, then this does not work. I would like to cut everything, then put a piece of painters tape over all the parts to move them all at the same time to another assembly. If some of the parts have fallen through, then I can’t easily do that.

AND, at the maker space, the crumb tray is not always cleaned out before I start, so I have to sort through other people’s fallen parts to find my own (that won’t be a problem when I have my GF).


#6

But if you just let the parts fall through then you have not only cut the intended parts but you have created a puzzle as well. Sounds like fun.


#7

:slight_smile: True. Fun, but not practical, especially with LOTS of small parts.


#8

Aluminum foil may reflect too much heat back, and cause additional scorching on your parts. Maybe a piece of stainless door screen would work better.


#9

Oh, I like that idea. Also, depending on how much you want to spend, you could get a perforated metal sheet from McMaster-Carr. http://www.mcmaster.com/#standard-perforated-sheets/=116zao3
Oh, Wire Mesh! http://www.mcmaster.com/#standard-wire-mesh/=116zcba

…Dang it, now I’m making a list of stuff I want to get from McMaster.


#10

To minimize blowback, wire mesh would be the ideal. Find the most open mesh you can without allowing your small parts to fall through, or tilt significantly.

If you really do not care about how the under side of your parts look, then aluminum foil should work quite nicely.

If you want to go the insane route, buy or build a plate of ZnSe or NaCl to put under all of your parts (I really cannot imagine how expensive that would be though)


#11

Ive been looking into getting a sheet or either of those, but the most I could find was 10mmx10mm for the zinc selenide, and that ran about $237. It would be such a cool option if there was another material that wasnt so expensive…


#12

Does it have to be pure NaCl, or just close enough, and non-combustible/non-reactive? Because those Himalayan salt blocks they sell at Costco for grilling are 95%+ NaCl, along with some polyhalite, iron oxide, and other goodies. And they’re ~$20.


#13

The more pure, the better the optical clarity. You are mostly just looking for a solid surface that won’t blow back and won’t be destroyed. So 95% would be far above and beyond.

I forgot about salt blocks. So I discounted an NaCl sheet as non-existent, but possibly could be made with extreme patience. But a salt block, and some method to sheer in to layers, you could cover the bed pretty easily.

And yes… ZnSe in a solid sheet would be absolutely insane.


#14

I have used Aluminum foil and glass to keep small parts from falling through, the glass works for a time at lower power levels but has a chance of breaking. the aluminum gave me no trouble with over heating and no chance of breaking like the glass. I have even glued wood to the aluminum foil when working with very small pieces, and that worked to my advantage do to the fact that the finished piece was being glued around a small metal tube for a pen I was making.


#15

@bblack, great profile pic!
I go through life with that look on my face.


#16

Hey, given that we still have a few months to wait, patience is a given! We could start evaporating brine in a foil lined big flat pan/cookie sheet now, and probably have a few sheets of it stockpiled by the time our Glowforges arrive!
I’m likely oversimplifying it, as I have no idea whether evaporation would even produce a smooth sheet or not, but it might be worth a try on a smaller scale to test the feasibility. And those of you that already have access to a laser could also determine how well it will work as a tray.


#17

McMaster-Carr is great! EXCEPT they won’t ship to individuals in Canada. They only ship to registered companies, and even then, it’s spotty. They won’t even ship stuff to a US address if the order is coming from Canada (so I can’t ship it to a friend in the US and then have that friend ship it to me). I’ve gone to ridiculous lengths to get an order from them.

I’ve stopped using them for that reason, but it hurts. It’s so easy to find what you want on their site.


#18

I’d say a half-sheet pan, cheap from a restaurant supply company, but it is 1" too wide (18"x13"). If you can cut it down though…


#19

In an open pan what you’ll get is a bunch of clusters of pretty cubic crystals, distributed according to the varying evaporation rates in different parts of the pan. To get anything different would require research (Google it!)


#20

If you ever need to preserve an assembly bigger than painter’s tape can do, there’s a product made for that: application tape, commonly used in signmaking.

http://www.uscutter.com/Application-Tape?view_all

You can get it in a variety of size and stickiness levels.