I am looking for an easy way to make a paint mask with my new Glowforge. I have searched the web but have found no good tutorials for what I want to do.
My first idea is to lay down a sheet of heavy duty aluminum foil from my kitchen, spray it lightly with spray adhesive, then lay down a sheet of PerfectTEAR or TransferRite white transfer tape, sticky side up. I am hoping I can then laser cut through the transfer tape but not the aluminum foil.
Then I can weed out bits of the transfer tape, stick it on the object I want to paint, peel off the foil, and apply spray paint through the mask.
Does that seem like a viable technique? Any better ideas?
Couple of problems with doing it that way…one is the foil. It’s just not sturdy/stable enough to stay flat when the air assist hits it. The other is placing the transfer tape sticky side up. It’s not going to stay stuck to the foil and you’ll have the same problem.
For cutting things like paper and thin tape/cloth/whatever, you need to create a cutting mat. It will hold the lightweight material down until you choose to remove it, and little bits won’t go flying all over the machine to stick to things and block the fans.
Cheapest route is a sheet of plywood or other flat scrap material sprayed with a couple of heavy coats of Krylon #7020 Repostionable Spray Adhesive. Let it dry thoroughly, and then you have a reusable cutting mat for anything that tends to fly around. (And the stickiness can be refreshed with another light coat of spray any time you need it.)
With something like that, you can lay the non-adhesive side of the tape down and it’s not going anywhere.
@Jules Thanks for the excellent advice! That totally makes sense. I wonder how I would then get the mask transferred to the object I would like to paint without any pieces of the mask shifting? Perhaps another sheet of transfer paper with medium tack (a little stronger than the repositionable, but less strong than the adhesive of the mask)?
Depending on how intricate the design, you should be able to just peel it off the mat.
The repositionable adhesive is just tacky, it doesn’t really grab hard. (unless you get it on too thick)
All the little cutout bits will stay behind on the mat, use a scraper and a spritz of water to remove those. After it dries, it becomes tacky again. (Digital cutters use something similar to corral the paper, but that kind is made out of thin plastic, and they’re expensive. You’d slice them to ribbons with a laser.)
If you have a tape with a liner, you would be able to use something like vinyl transfer tape to apply it, but by that point you’re getting into a lot of layers. Might not be worth it.
@Jules Sure, just peeling it off the mat would work for some paint masks, but I still don’t know how to make a transferable mask that has “islands” in it (like the little shapes inside letters). I will definitely follow the rest of your advice, though, and if I figure out a way to transfer the whole mask at once, then I will post my solution for the entire community.
I don’t know how you’re going to do it either without a liner. In order to transfer stencil material with cutouts, it’s generally got a liner on it, and you use vinyl transfer tape to transfer the cutouts to the object you want to mask.
Trying to use upwards facing sticky tape is gonna be a problem. (Maybe you could apply a liner of some sort, but by that point, you’re almost better off just buying one that has one already. I probably didn’t explain that well enough.)
@Jules Right, that’s what I figured, and why I was thinking of using aluminum foil as a liner, because it wouldn’t be cut by the laser. Based on your earlier advice, here’s what I’m gonna try (and report back on):
(1) Sheet of scrap plywood
(2) Spray plywood with repositionable adhesive
(3) Smooth aluminum foil onto plywood & adhesive
(4) Spray top side of aluminum foil with more repositionable adhesive
(5) Smooth transfer tape onto top with sticky side up
(6) Laser cut through the tape, but not through the foil
(7) Weed the cutout bits of tape off of the foil
(8) Peel the foil with tape mask off of the plywood
(9) Apply foil with tape mask to the object to be painted (in this case, vinyl upholstery)
(10) Peel foil off of object, leaving mask stuck to object
(11) Spray-paint object (in this case, using paint designed for vinyl upholstery)
(12) Remove mask from object
…
Profit!
Should be an experiment worth seeing. (Unless someone else pops on and says don’t do the aluminum foil…only thing I can think of is possibility of reflection back up into the lens, but I don’t know enough about it to say definitely okay or not.)
step # 5 sounds to me like it could be problematic.
is the object to be painted flat, or dimensional?
If it is flat, I could see making a semi-matched pair of stencils, with the connections to “islands” offset from each other.
Why not? Won’t it stick to the sticky spray the OP was going to spray on the foil first? Does the transfer masking not stick on the outside surface? I’ve never tried but it would not have occurred to me that the transfer tape had a non-stick finish.
I thoroughly applaud your dedication to finding a GF solution
Looking over what you @will_bain are trying to accomplish I gotta be honest - I don’t think GF is the best tool for this. What you’re describing is exactly what a vinyl cutter does very well. Granted, you probably don’t have one. It’s pretty cheap to have a sign vendor cut vinyls for you or a 12" hobby model called Silhouette Cameo can be had for under $250.
I was thinking more if they lay the tape sticky side up, they will have no good way to press down/squeegee/burnish to get it flat… not impossible, just can be very difficult to work with adhesive films sticky-side up.
instead if aluminum of any variety I would bet that a sheet of thin Stainless Steel would not be hard to come by and would last a very long time. A critical thing to remember is that while Aluminum is very hard to start burning the energy released is awesome, and more to the point the strength of the bond means that it will grab oxygen off of anything that has oxygen in it. Water and carbon dioxide are like pure oxygen to it!
I am not saying that the laser would start such a fire, and anodizing would pull back the reigns a bit, as would aluminum of enough thickness to dissipate the heat, but the aluminum foil is none of those things, and that would up the possibilities.
@john.m.gaffney That could work, too. I have just two concerns: (1) I would need to be careful not to cut through the backing, and (2) The mask needs to stick to the object better than the adhesive sticking the mask to the backing. It will take some experimentation.
@jbv Yeah, applying the tape sticky side up will probably fail. Maybe I could use a teflon film or something similar temporarily on the sticky side to make it easier.
@rbtdanforth Stainless steel would certainly be better, but it wouldn’t be very flexible for attaching the mask to a curved surface (unless there’s such a thing as stainless steel foil?) If there’s a chance that the aluminum will burn, I had better experiment first with very small patches of it!
the stainless steel that they use over other things like refrigerators is very thin and would easily take a curve but its strength would not let it crinkle like foil, and it would not become thermite!
