Hold down pins

[djfb]

After the first pins were shared, either the originator or someone else released a modified version. I can’t for the life of me find the file. Does anyone know where it is?

[evansd2]

Hmm.

https://community.glowforge.com/search?q=Pins%20%20%23free-laser-designs

A few posts down the list…

Honeycomb bed holdown pins

the best laser results are achieved with flat (non warping materials) in order to maintain consistent focus. Also, when cutting light materials like paper, the exhaust turbulence can kick up the material and ruin your job or at worst… catch fire. (speaking of which, I hope you all keep a small fire extinguisher in easy reach, near your machine - safety FIRST) I hope you find these useful. I used to 3d print them for my other laser cutter but occasionally , they would see the wrath of the laser …

[CMadok]

Do you mean the one @eflyguy shared, with the different sides for passthrough stuff?

[djfb]

No but I would like to know that too, please.

[CMadok]

This isn’t it, but it’s modified so the middle is more springy? Just so you don’t have to scroll forever throught the post:

Honeycomb bed holdown pins

I had to adjust the size a bit for my bed, but here’s a new version from Phil’s redesign with the center cut as a separate color. I found that my was cutting the outer line first and the center wasn’t always clean. Separate colors let me re-order the cuts. Honeycomb Bed Pin.zip (947 Bytes)

Found it:

Passthrough hold-down pin

I have found long materials tend to not be as flat as proofgrade sheets, so I’ve been using hold-down pins but not pushed down all the way so that I can slide the material down during each step. They also act as guides for the edges of the material. I decided, why not make a versions specific for this task, then realized they work just fine as regular hold-downs as well. I present: [image] Passthrough pin.svg.zip (2.4 KB) I use 4, one at each “corner” where the material enters and exits th…

These fit tighter on my honeycomb, I don’t know if I changed the size on accident, but you might want to cut one first and try it out.

[djfb]

Yep, that’s what I was looking for, thanks!

[vicberggren]

This is such a good topic and a must read for anyone new. It could save you some re-cutting and valuable materials.

Why do you need pins? One reason is that all material is not created flat. The Glowforge is a very precise instrument and I found out the hard way that a slight bow to a sheet of wood can result in the laser not cutting all the way through the wood.

Take a look at this piece (not proofgrade). It’s slightly bowed just enough for me to get my masking tool underneath.

Doesn’t seem like a lot but it is when the machine thinks it’s cutting a 1/8" piece of wood and it directly caused this outcome.

So, when your wood is flat on the crumb tray, tap around to make sure it sits flat in all of the areas. If you feel any play at all, use hold-down pins to help ensure a good clean cut.