Fin question

[bigone5500]

I am in the process of building the Estes Interceptor and have the fin/wings ready. I want to use the technique that you coat the balsa with paper. What tips can you give me to make this work without having bubbles or warping?

 

[SecretSquirrel]

https://www.rocketryforum.com/showpost.php?p=500740&postcount=4

 

[Race58]

Some use sticker paper and they seem to like it. I use 3M Super77 spray adhesive. I spray the paper then stick the fins to it. I then spray the other side of the fins and lay another piece of paper on top. Rub it with your hands and let it sit for awhile. After that just cut the fins out and CA the edges. Works for me.

 

[paparoof]

Some use sticker paper and they seem to like it. I use 3M Super77 spray adhesive. I spray the paper then stick the fins to it. I then spray the other side of the fins and lay another piece of paper on top. Rub it with your hands and let it sit for awhile. After that just cut the fins out and CA the edges. Works for me.

I use the 3M Super 77 stuff too. After gluing the paper and the fins, I stack it all with wax paper and set it underneath a dozen 12" ceramic tiles. I usually leave it under the tiles overnight. The weight keeps everything flat and smooth.

 

[bigone5500]

What's the nominal drying time for Super77?

 

[Race58]

.

 

[Race58]

30 Seconds it says on the can and I believe it. I was able to cut the fins out right away after sticking the computer paper to it with no trouble at all. I did stack some books for weight on the assembly like Paparoof for about 15 minutes.

What's the nominal drying time for Super77?

 

[Stymye]

they can be cut out in about 15-30 minutes. If you apply the paper on a flat surface you shouldn't need to weight them down, I paper both sides one right after the other.

 

[Race58]

I think stymye is right even though I haven't tried yet. Right before I put the books on them I noticed that they seem to be stuck pretty good already with no wrinkles.

 

[aerospike]

Personally, I prefer Jap tissue and dope for LPR.

 

[bigone5500]

I weighted them down overnight after applying cardstock to both sides

BUT

I did a test with a scrap piece of balsa and cardstock with Super 77 spray. I sprayed a decent coat on and immediately stuck the paper to it. After about 10 seconds, the paper left approximately 75% tear. I think it's safe to say that 15-30 mins is sufficient for adhesion with this adhesive.