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View Full Version : Laser cuttable sandblasting resist.



Joe Hillmann
01-15-2014, 1:02 PM
I am trying to find a way to make sandblasting stencils for items I can't fit in the laser, due to size, shape (being unable to focus on a large enough area).

Right now I tape a piece of vinyl paint mask to the bed of the laser, kiss cut the design, weed it then use transfer tape to put it on the item.

There are several problems with the method I use now.
1 The vinyl probably has PVC in it
2 Doing the weeding and transferring takes a lot of time.
3 If there are small details some may not peal off the backing with the transfer tape or stick to well to the transfer tape when it is removed from the glass.

Is there any sandblasting mask that is designed for laser cutting? And can be cut then put on to the item rather than being cut after put on the item?

If not are there any photo methods that would work well on items that are curved in multiple directions and don't require expensive equipment to do?

Gary Hair
01-15-2014, 1:44 PM
Joe,
First, Vinyl is PVC - the "V" is vinyl. Others may argue that it's ok to cut small amounts of vinyl in their laser and as long as it's "their" laser I'm not going to argue...

I do a lot of sandcarving/sandblasting and use Anchor products, they are polyester based and laser really well. I use 116 for heavy work, hard materials that I may cut up to 1/4" deep, and 117 for lighter engraving and smooth surface materials. The 116 sticks too well smooth surfaces like polished granite and is difficult to remove and leaves adhesive residue. For light work, glass, etc., I use Ikonics laser tape, it sticks really well and peels right off when soaked in water for a few minutes. I raster the tape but vector the 117/117. Weeding is a pain, I spent about 4 days weeding a veterans memorial last year...
I probably laser about 50% on the item and 50% off, if you experiment a bit you'll find the right settings to kiss cut it. I would prefer to do 100% on the item but I haven't found a way to fit a 500lb slab of granite in my laser. One caveat - don't cut a bunch of stencils and wait to weed them - it's almost like the cut "heals" itself. I find that if I'm doing bricks, for example, that I can weed them about as fast as the laser cuts them, if I get more than a couple behind then I'll stop lasering and focus on weeding. I learned this the hard way when I lasered almost 100 bricks and then started weeding - it took at least 4 times as long to weed because the letters didn't want to come out without a lot of work.

I have used photo resist and it works really well but is a pain for small jobs. I use my old HP 1100 laser to print on transparency film and I built a black-light exposure unit - definitely a low-budget setup if there ever was one.

Gary

Joe Hillmann
01-15-2014, 2:13 PM
Thanks Gary. I will take a look at the products you mentioned.

Rodne Gold
01-15-2014, 4:38 PM
We use 2 materials , paper based self adhesive tape used to transfer vinyl cut letters (called application tape) which is a good resist for shallow blasting (we apply it , laser it away and blast - comes off easy when wet and you can get incredible detail doing it this way - you can vector kiss cut for large solid areas of blasting and raster away for very fine detail)
And we use the shiny mirror vinyl which is polyester based for deep blasting , it's an excellent resist , but a bear to remove. same process as the tape

Joe Pelonio
01-15-2014, 8:27 PM
I also use Anchor products, mostly cut it on the plotter but also on the laser. I have also engraved it to make logo molds for someone manufacturing sneakers, of all things.