hi temp tape shrinking

[craigcraig]

i used the tape i got from caswell to tape off some spokes on a rim and then i stuck it in the oven to pre-bake and the tape shrunk. so i had to pull off all the tape and do it again. and let me tell you taping each spoke sucks. anybody else have this problem with the tape

[DALE]

Yup it shrinks,which makes it nice to remove after curing.I only mask after prebake.

[jagboy69]

screw the tape... Aluminum foil... It wont shrink I promise!

[pdeinc]

I've been having good success with just good qualilty blue painters tape. I cure at the required 400 degrees for 20 minutes and altho the tape darkens and becomes brittle, it doesn't shrink or fall off and can be removed without leaving much in the way of residue.

[jagboy69]

No kidding You mean that new BLUE 3m tape that is advertised on TV?? It is a little pricey for tape, but if you say it works....

[pdeinc]

Yeah, no kidding. I was surprised myself. I use a lot of the blue tape in my fibreglass and painting work and had always been impressed with how long it sets in the Florida sun with deteriorating so I thought I'd give it a try. It turns dark brown and gets brittle, but the glue does not let go and will come off with a minimum of residue. I just finished a Holley 650 DP carb last night and it took all kinds of masking to spray. I used that tape everywhere without a problem. Certainly no shrinkage issues with it.

[jagboy69]

well... thats the last time I buy special powder coating tape... Tin foil and blue home depot tape for me!
THANKYOU!!!!

[pdeinc]

Well, just because it's blue doesn't necessarily mean it will work. I'm using the best quality of the Scotch 3M tape, so be sure to look for that.

[pdeinc]

Caveats!!

Some caveats may be in order here. I just finished my carb base and based on this most recent use of the tape, I can't heartily recommend it!

It's a new roll and maybe the formulation changed or the application is different enough, but it was a PITA to get off. And it left lots of glue residue. Go figure!

The previous uses were an aluminum intake manifold, an aluminum water pump and an aluminum alternator housing. In nearly every case, the tape was laid across a flat surface and trimmed around the edges. A varying amount of what the tape covered was open air space, ie the carb mating surface of the intake manifold, or the mating surfaces of the water pump. In these applications, the tape turned slightly brown but was able to be peeling off nearly intake - it was brittle. A quick wipe with lacquer thinner cleaned off any glue.

The most recent use was the base plate for a Holley carb. Again the mating surfaces were covered plus all the linkage on the side of the base. The tape did NOT remove easily from the mating surfaces, but it wasn't much of a problem since they were flat. The linkage was another story, as I said, major PITA. And left lots of glue!

I also bought some purple 30 day tape and used it on the bottom of the plate. It's glue was not very aggressive and altho did not fall off, it gave me some concern. The tape did remove better than the blue, but not like previous uses.

So there you have it. Proceed at your own risk. YMMV. Please report back on successes/failures so the rest of us may know.

[johnny933]

I use the green hi-temp tape and have no problems with. Yes, once the part is fully curred it might wrinkle some but it does it job. I use the green hi -temp with no problems on 1, 2 and 3 coat applications. Stick with the hi temp. It might peel and curl when done but will come off eaisly. Tape is used for protecting those areas when coating that you dont want the powder to go on. If your doing a two or three stage coating and the tapes peeling/lifting then I think the user has gotta be over curing there first coating.
Just my opinion as I have had no problems with the hi-temp g. tape.

[pdeinc]

I haven't noticed the green tape, but then again wasn't looking for it. Thanks for the tip.