Paint masks

[joa]

Anybody have any ideas for something that is sticky backed to cut out a stencil for use as a mask for spray painting. It can't be *too* sticky so it peels off the paint underneath. I'm too cheap (and in too much of a hurry) to order something from a sign supply shop. Anything that can be picked up at Home Depot or Fred Meyers (WalMart, Kmart, etc etc)? I thought of the stuff you put in the bottom of your kitchen cabinets but figured it might be too sticky.

Also, does Exacto (etc) sell a swivel knife? Any other options rather than going with a fixed blade?

Thanks!

Joa

[b1705@bellatlantic.net]

Joa, when I'm trying to do something quick/dirty like that I just use the spray adhesives that are made by a few different companies. If you spray one side of a joint ( or just the mask) it will peel off easily. If you spray BOTH sides it is like contact cement, and a real pain in the butt to remove...I think 3M has a pretty good product, about 5-6 bucks a can, which will last you a long time...

[joa]

Bill, Oh, thats good too. Hadn't thought of spraying something.

After I wrote the message I stopped by the stationary store on the way home and lo and behold I think they have just what I'm looking for. Called Frisket and I've heard it referenced but never knew what it was for. I also got a swivel knife there. Only thing I'm worried about with the Frisket is that the paint will bleed underneath (the darn stuff gets under about anything it seems.)

You know, I think I'll try to mount the swivel knife in the SB and see what happens, it should work for the size of letters I'm cutting out (N-Numbers). If it doesn't work I'll do it the old fashioned way, plot and cut by hand.

I think I'll use the Bertram font, it's different and looks neat. I'll let you all know how it turns out.

Joa
"vinylcutterignoramus"

[pjldesigns@hotmail.com]

I've used vinyl that the sign shops use for making vinyl cut letters. You can get different grades (thicknesses) and grades of adhesive. I've also used MACTAC shelf liner. Both work very well. For cutting I use a very sharp 60 or 45 degree Vee bit in the router and cut through the vinyl at about .020 to .030 deep. If you plan it right that small cut will disappear when you do the final routing of the design.

I first prepare my wood as follows:
1) Plane and sand as desired to get an even surface.
2) Prime the wood with a sealer. Clear lacquer from a spray can works good. If you omit the sealer step you could get bleeding from the coats of paint down into the grain of the wood which detracts from the final result.

3) Determine which color is predominant in your design and spray that over the wood.

4) After the paint has dried cover with mactac and then cut through the area that you want for your second color and spray paint.

5) Cut the design into the wood.

6) Repeat with layers of MActac and again cut out areas to paint and then paint over them.

Repeat steps 4, 5 and 6 as many times as necessary.

I will try to find my photographs and post them on the ftp site to show how I used this technique to make a HAIDA type carving in red and black and natural wood color.
Phil

[garbob]

Good idea Phil!

I'm not sure about the price of mactac, but a cheaper alternative to vinyl sign lettering is premask sold in all kinds of thicknesses, widths and tackiness. A sign wholesaler will carry all of that stuff.

[Cliff Haldeman]

I don't know if this would work,but here are a couple of ideas I thought of while I read about your other good ideas.---(1)instead of some kind of paper or adhesive maybe a peelable spray-on paint booth coating would work.It adheres good and peels off easy.I think sign painters use a similer spray-on peel off material for masking.---(2)for a quick short cut you can buy prefinished plywood in different stain colors and they ship it with a peelable film to protect it during shipping and machining!!! It's available from cabinet makers supply companys

[ditapo]

Hey, I thinking about buying a shopbot. Joa was making N number stincels so I'm hopeing he's using his shopbot for airplanes. I'd like to hear about what it has done in aviation related projects.

[birdsofplay]

Oh man !!! now you're gonna ge the FAA
involved. We'll hafta start doing 100 hr
inspections on our SBs and add those danged
encoders back on the machines !!!
Or at least get a GPS for tool navigation.

Happy Bird day :-)

[studebaker]

Yeah, but the C-checks get expensive! I would probably have to replace the servo motors every time.

Happy landings!

[epatsellis@mcleodusa.net]

as an alternative, you can buy vinyl that has a removable adhesive, I use 5-6 rolls a year, very little if any adhesive residue, ready to use, and about the same price as regular vinyl

[transdude@msn.com]

After struggling with plastic film painting masks, I say phooey!!! Here's the trick, I've used this for over a year so I feel confident in sharing it as "road tested". Take a sheet of 1/8th" tempered hard board (about 5 bucks a 4x8 sheet), an 1/8th inch cutter, a working shopbot, a vacuum table, Corel Draw and Partwizard or similar, a little shopbot experience and an orbital sander. Put all of this in a bag and shake it up and you should be able to come out with durable, reusable, inexpensive, stencils. Instead of spray adhesives etc.. I recommend a relatively old product but it works great and it's virually free. Gravity. In my area there is sufficient gravitational force to hold these stencils in place (this may vary in your area especially if you're from the moon). Paint textured side up, smooth down. After many paintings you will of course get build up. Clean them by throwing them into a circular file and repeating the above procedure. These of coarse work best on flat, horizontal surfaces. If you need to paint letters on 55 gal. drums full of old oil from your back yard turkey fryer you may have to give up on gravity and invest in some of Red Green's duct tape, but I'll bet you could do it! If you have further questions concerning these babies, try one of the following: A: risk 5 bucks and try it. B: Bang your head real hard on a work bench, wait for an answer... if no response bang again, wait... bang again, wait.. bang again. I find this very effective. C: Post me a question, remember, there are no stupid questions, only lack of thought before asking an embarassing question with an obvious solution. I have also found this to be very effective.


Happy ShopBotting,
Keith

[bjwat@comcast.net]

Keith,
I'm having trouble with the circular file. It seems that my system will only handle rectangular ones. Is there a patch available? I already tried A & B, and I'm out $7.50. I spent $5 on the hardboard and $2.50 on asprin and bandages.

What can I do???




-Brady

[transdude@msn.com]

Brady,
This would fall under catagory C. of "there are no stupid questions..." I suspect what is wrong is that your circular file has been converted to what we here on the farm call "the verticle pile". A working patch should be readily available. Here again duct tape is the answer. Pick out a nice roll, I know you probably have serveral types but please use the good stuff, this is not the time to skimp. Run the patch over AND around the verticle pile. This should restore it's function, but you may need to run the patch again for repeated and continued use.

Good example of "UNDER USE" of step B. but thank's for the obvious question.

Tip of the Day: If you develop file access problems, try standing on your ShopBot table, just watch out for that moving gantry if you are running a file!

While I have your attention, I have this idea about using the Z axis as a beer can crusher?... oops, I guess that's getting off topic. I should start a new "Project Ideas" thread for that one.

Have a good, no Have a GREAT day Shopbotting!
Keith

[kerrazy]

Has anyone actually been able to convince someone to lie still enough to get probed yet?

Just curious ;)

[mbarinholtz@chdc.org]

Dale -

I actually spent seven years in Roswell, New Mexico, and along with using Frisket film and 3M Blue tape for all of my masking needs (3M also makes a great pinstriping tape, sold at auto body shops in many widths - it's orange, expensive, but extremely flexible and will NEVER bleed under or tear your edges, unless you coat too thick), I believe I have met several individuals who had either been probed, or needed to be - what are the proper feedrates for 4/4 walnut in zero g's at warp factor 6?

Hey - I thought that this thread was about masking?

[rgbrown@itexas.net]

"what are the proper feedrates for 4/4 walnut in zero g's at warp factor 6?"

To find the proper speed in cubits/fortnight we will need to know the bit size. I will calculate that as soon as I can get the centers of the "O"'s; "A's"; "R"'s and such to stay in place when I pick the hardboard masks off the vacuum bed. Well, actually, the centers stay on the bed and not with the rest of the mask.

BTW - "Cor-Plast" seems to work well for masks also too.

[Transdude@MsN.CoM]

Sorry Ron,
This sounds like an option C. No such thing as a stupid question again.

Again the answer is Duct Tape.

None of the masking that I do deals with lettering, but if I had run out of duct tape (Never!) the obvious solution is to avoid words with "O"'s, "A",s, and "R",s.


Keith