When blue tape isn't safe

[Sven]

We often do varnish on the spur of the moment; the sun is out, no other chores, let's add a coat ! Some light sanding and then tape it all off with the low-adhesion blue masking tape. Works like a charm.

But not always ! When we last did the eyebrow on Senta II we were left with a sticky tape residue after removing the tape a day later. Getting the residue off was a real pain, even oil and liberal waxing didn't want to do it. We didn't have any Goop Off or Goo Gone or whatever it is called. The tape said it was safe to leave on for days or maybe even a week ?

We asked our favorite chandler (who used to be a painter) if blue tape ever went bad like what we'd seen. He immediately replied that "yes" moisture or dew can do that to you. I believe he knows what he is talking about and he gave us a sample if a silvery masking tape he said we should use outdoors if there might be dew overnight.

I'm still curious if this has happened to anyone else here ? I wonder why it hasn't happened to us before, I'm sure we've left the tape on with dew overnight ?



-Sven

 

[Lucky Dog]

Yes, I used 3M blue tape when it first came out to mask off copper flashing on our house. It rained that night. Three days later I sprayed 3 coats of stain on cedar shingles over three days. That was five years ago, it still there.

I have checked with painters as well. The advice is to use a heat gun to get tape off and spray adhesive remover to get the masking off. "Use blue take to mask the shingles for the adhesive remover doesn’t hurt the shingles". - Just take it off right away.

Good Luck.

ml

ps- We started FIRST robotics with my students this last Saturday. At the kickoff the head of NASA spoke about a engineer at JPL that helped desgin a tool for the mars robot that got is interest in engineering and robots when he was a student... thought of you.

 

[CSMcKillip]

Yes, I had the green tape, not the blue stuff when I re painted our old boat, took me three months to get all of the tape off, it was a total pain.

 

[treilley]

3m makes a blue tape that is safe for 60 days. I use that for everything. Never had a problem with sun or moisture. It is part number 2080.

 

[MarkA]

3m makes a blue tape that is safe for 60 days. I use that for everything. Never had a problem with sun or moisture. It is part number 2080.

I've had 2800 leave some adhesive behind after only an hour. Since it was on metal, I wiped it off with a rag squirted with WD40.

 

[u079721]

Different technques?

I find this discussion pretty interesting, since I was taught to remove the tape immediately, just as soon as the varnish had leveled and was no longer flowing. This has the disadvantage that you might accidentally touch the fresh varnish while working around it. But the big advantage (other than having the tape not get stuck overnight) is that you catch any areas where the varnish has run under the tape, so you can clean them off while it's still fresh.

I guess you guys don't do it this way.

 

[Sven]

I find this discussion pretty interesting, since I was taught to remove the tape immediately, just as soon as the varnish had leveled and was no longer flowing. This has the disadvantage that you might accidentally touch the fresh varnish while working around it. But the big advantage (other than having the tape not get stuck overnight) is that you catch any areas where the varnish has run under the tape, so you can clean them off while it's still fresh.

I guess you guys don't do it this way.

If working with paint I always pull the tape off right away to avoid capillary action pulling the paint under the tape. Since varnish is pretty clear I guess we don't see the "hairy" edge you'd get with paint, or maybe varnish is too viscous ?

So I agree with you about pulling the tape off with paint but we don't do it with varnish for some reason.



-Sven

 

[Flight Risk]

Get froggy with it!

I am in the process of getting my other boat (a San Juan 24) ready to sell. I mask off the boot stripe before putting on a fresh coat of anti-foul and have used 3M blue tape in the past. Never had any real issues other than occasional goo left behind.

On the advice of my friend who works in the local yard I used the green "Frog Tape" stuff this time. Yes, Frog Tape is the brand. The info on the package claims the adhesive swells up and seals when in contact with latex paint to form a sharp edge.

Figured worst case was to buff the hull again if it screwed up with the solvent based Interlux paint. Painted, waited about four hours and pulled it off. Perfect sharp line and NO residue! I would use frog tape again in a second but maybe do a "test" spot to see how it reacts with other non latex finishes.

Chris
E34 Flight Risk