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John Bion
10-19-2017, 4:48 AM
I had this very difficult, large, item to try and laser engrave, trying to set up jigs to hold it was a nightmare. This idea suddenly popped into my head, someone else may find this useful at some point:
369924

PS: I do not know why the image is upside down when I upload!

John Lifer
10-19-2017, 8:03 AM
styrofoam peanuts? Be CAREFUL! very Careful! lots of air pockets to hold flame. Yeah I know your careful and safe, but I'd rather use my magnets and other scraps. Air assist would blow them into corners easy.

Scott Shepherd
10-19-2017, 8:05 AM
Modeling clay stuffed in a large plastic bag has always worked well for me. You can squish the part down into it, build it up where you need to, and move it all around. It holds tight.

John Bion
10-19-2017, 8:21 AM
This was a desperation “Jig” :)

The part had to be held 1.5’ off the table, resting on a spear point end with multiple angles. Tried all my usual stuff, including a heap of putty and could not get it level in all directions. Thought it may be useful to someone in a desperate situation, as I was. I well understand the dangers, although it is right to point out the fire hazard for others. Also, I do not use any air for this (the cone is off), so no blowing the polystyrene around.

The modelling clay in a bag would be a good idea. Thanks for that Steve.

Kind Regards

Bert Kemp
10-19-2017, 10:49 AM
369928here ya go

John Bion
10-19-2017, 10:53 AM
here ya go

Thanks Bert
:)

Kev Williams
10-19-2017, 11:19 AM
For larger stuff, a small bubble level, a towel and a few pieces of scrap Sintra or wood as shims or 'stabilizers' and I'm good to go. Smaller stuff like knives & such, just a towel. Nearly every AR lower I engraved on the fiber I just sat on a towel, just squish it around till the bubble says it's level... :)

Tony Lenkic
10-19-2017, 11:53 AM
Various sizes of "Lego Blocks" are another way to build holding fixture.

John Lifer
10-19-2017, 5:51 PM
John, I get desperate occasionally too! Just had to put in note for anyone reading later. Guy posted that he eliminated flash back on his solid Epilog laser by using sheet of paper behind plywood. Works, but sure to offer the chance of fire and sure enough a couple of posts later someone said doing the same damaged her laser.

Kev Williams
10-20-2017, 1:57 PM
Not sure how it could damage the laser, unless it caught on fire. I've used paper in my solid table machines, since I don't cut where paper is overhanging there pretty much no no chance of fire. Sometimes I spray the paper with water first, helps with the goo I get cutting Rowmark. Mostly if I need a 'buffer' I just spray the table with water- I put just a hint of dish-soap in it so it looses it's cohesion and flattens...