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Old 03-22-2011 | 09:09 PM
  #19  
VerneK
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Joined: Mar 2005
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From: Livonia, MI
Default RE: Blenderm

Okay, got er done. I ended up using most of Mark's first suggestion on my rudder. I pulled the tape out the full length of the hingeline without cutting it off the roll (gave me a temporary handle). The real trick was to get that first 1/8" down straight without stretching it as Mark suggested. Once that was done, I cut the tape from the roll. I ended up putting it on the rudder half of the hingeline first so that the excess would be on the rudder post at the trailing edge of the vertical stab, or fin if you prefer. More on that later. Then I took a 3" wide bindo spreader and burnished the tape from the edge of the 1/8" strip already secured to the hingeline. I started in the middle of the rudder and went up toward the top first and then down toward the bottom second, making sure to overlap the portion I just finished burnishing so I wouldn't trap any air. As I expected, portions of the tape had grabbed the rudder post along the way. I just took my time and got those spots lifted back off the post so that the leading edge of the tape was free. For this edge, I used the bondo spreader to secure the first 1/8" to the rudder post at the hingeline with the rudder fully deflected. Once that was done, I just started in the middle and burnished it just opposite of the way I did the rudder, burnishing from the hinge line toward the intersection of the fuse and rudder post. The technique of overlapping was done as before to prevent trapped air (bubbles). Everything looked great and now I just had the overhang to contend with.

The reason I wanted the overhang to be at the rudder post of the vertical stab is because it's finished with 3/4 ounce glass cloth which gave me a nice, relatively hard surface to cut against. I used an X-acto with a standard #11 blade and basically scored the overhang just inside of where it was sticking out. I grabbed the edge and it peeled off nice and clean. Done! Then I repeated the process on the other side of the rudder.

Thanks for all the tips everyone. I hope this wordy description helps out someone else that has struggled with this in the past. I still like Archie's idea of using vinyl application fluid, though I didn't use it here. Had I done my ailerons with Blenderm, I probably would have gone that way.

Verne


ORIGINAL: ArchNemesis

Hey Verne,

I've had pretty good luck sealing hinges with Blenderm. No real ''tricks'' persay, but if there is one, it's DON'T STRETCH it. I'm careful to attach about 1/8'' to the wing for the entire length and then working from the center of the aileron, with it fully deflected, attach it to the aileron.

The real problem comes AFTER that, in that it when you deflect the surface the other direction, the tape attaches to the inside of the hinge gap and doesn't release well. I've solved that but putting talc into the gap area after attaching the tape so that the talc will cover all the open tacky surfaces of the tape and prevent it from sticking. Never had a problem after that.

Rereading this it's a pretty cryptic description of my process. Give me a shout if you need more.

-M