Solvent for Gap-Seal tape prep

Hi y'all,

I have to replace the cloth tape gap seal after loosing the one on the rudder in flight. I removed the adhesive residue with GooOff, which worked really well and washed the area with denatured alcohol. The new tape still won't stick very strong. The glider is metal with PU-paint.
What surface prep solvent can you recommend to make the tape stick?
Thanks for the any advise,

Uli
'AS'

Which denatured alcohol did you use? Be sure to use at least 90%. Second, mask off the area that will be taped and lightly sand with 1000 or 1500 grit wet sandpaper. Sand just enough to dull the surface.

Forgot to mention I also use a small roller, designed for installing pill and stick flooring, to push the tape down to insure full contact of the adhesive.

On Sunday, August 13, 2017 at 2:01:31 PM UTC-4, Tim Taylor wrote:
Forgot to mention I also use a small roller, designed for installing pill and stick flooring, to push the tape down to insure full contact of the adhesive.

Thanks, Tim! The Denatured Alcohol I use is the pure stuff - not Rubbing Alcohol. I will try sanding and the edge-roller.
I was wondering if Acetone would be a better choice to clean up but am not sure if it does attack PU paint.

Uli
'AS'

Uli,
I have found acetone will attack most paints. I use it on gel coat sparingly, but try to use less aggressive solvents if posible. I use the 95% "rubbing" alcohol for most daily wing tape clean up. Works well and and dries clean without an oily feel. Also, see I fat fingered the "peel and stick" tile.
Good luck,

Tim

On Sunday, August 13, 2017 at 11:51:18 AM UTC-7, Tim Taylor wrote:
Uli,
I have found acetone will attack most paints. I use it on gel coat sparingly, but try to use less aggressive solvents if posible. I use the 95% "rubbing" alcohol for most daily wing tape clean up. Works well and and dries clean without an oily feel. Also, see I fat fingered the "peel and stick" tile.
Good luck,

Tim

3M Prep-sol. Works well and doesn't attack the paint like acetone. You do have to wipe it dry after application though.

Craig
7Q

I sand the area where the stickie will go with 200 grit and sand the inside (10mm) of the Mylar with 200 grit also. Then wipe everything down with Acetone.........it won't hurt Poly Urethane. Mask off the area to insure the Mylar goes on straight, then roll it down with lots of pressure. I use a 1" bearing on a stick.
JJ

wrote on 8/13/2017 3:37 PM:
I sand the area where the stickie will go with 200 grit and sand the inside (10mm) of the Mylar with 200 grit also. Then wipe everything down with Acetone.........it won't hurt Poly Urethane. Mask off the area to insure the Mylar goes on straight, then roll it down with lots of pressure. I use a 1" bearing on a stick.
JJ

Is the sanding on the Mylar to roughen, or to remove a surface treatment that
interferes with adhesion? I ask because the Mylar tapes I've bought with the
pre-applied transfer tape are not sanded underneath the transfer tape, and I don't
have any adhesion problems with them.

--
Eric Greenwell - Washington State, USA (change ".netto" to ".us" to email me)
- "A Guide to Self-Launching Sailplane Operation"
https://sites.google.com/site/motorg...ad-the-guide-1
- "Transponders in Sailplanes - Dec 2014a" also ADS-B, PCAS, Flarm

http://soaringsafety.org/prevention/...anes-2014A.pdf

I used some Mylar that came with adhesive applied and the customer returned after one wing shed its top Mylar after he took the bird near redline! That's when I decided the process needed better "tooth"! Without sanding you are asking the adhesive to hold one smooth surface to another smooth surface.. I have had no problem since I started sanding both sides with 200 grit and wiping both sides with Acetone just before application. Also, when replacing the transition tape, be sure to wipe the area with Acetone just before applying the new tape..............remember the bailout at Uvalde after the newly applied transition tape lifted and the pilot thought he was unable to maintain pitch control. The pilot had removed old transition tape, waxed the bird and then re-applied new transition tape over the wax!
JJ

If you live in a cold climate or are trying to do this in the winter, you should also use a heat gun or hair dryer to warm the surface, transfer tape and mylar as you use the roller. Don't get carried away with the heat, as you can easily damage the mylar and/or wing if you get things too toasty. Sometimes I also go back over the bond after a couple of days with the heat gun and roller. Don't melt the safety tape.