Spray Adhesive Question / LJ II

[Molniya]

With timely delivery of my Little Joe II kit before the blizzard yesterday, I've decided to start the build as the snow piles up outside.

Apologies up front as i'm certain this question has been addressed many times. I am considering using 3M 90 to attach the body wrap.

In full disclosure i have not had great luck with this fixative building the Sat V most likely due to a heavy application causing some crazing on one of the wraps.

Suggestions for how to best apply the aforementioned or better ( less idiot proof ! ) alternatives much appreciated. Thanks !

[tbzep]

Spray a few light coats instead of a single heavy coat and allow time for the solvent to flash off before it damages the styrene.

[LeeR]

3M 90 is rated as a high strength adhesive. I think I'd pick lesser formulations, like 77 or 45, and not run the risk of ruining the wrap. I have used 77 a lot in the past. The last time I bought spray adhesive, all I could find I'd Elmers. I used it on my styrene wraps on the Estes Saturn 1B with excellent results.

I mentioned in another thread that Hobby Lobby carries both 3M 77 and Elmers. The Elmers was about 1/2 the price of the 3M.

[tbzep]

3M 90 is rated as a high strength adhesive. I think I'd pick lesser formulations, like 77 or 45, and not run the risk of ruining the wrap. I have used 77 a lot in the past. The last time I bought spray adhesive, all I could find I'd Elmers. I used it on my styrene wraps on the Estes Saturn 1B with excellent results.

I mentioned in another thread that Hobby Lobby carries both 3M 77 and Elmers. The Elmers was about 1/2 the price of the 3M.
High strength doesn't necessarily mean high volatiles/solvents, which is what ruins the wrap. 3M Super 77 is only rated for HSE plastics, where 3M 90 is rated for both LSE and HSE. Odds are it won't craze the styrene as easily as Super 77. Use light coats with either one. Testing on scrap styrene material would be a good idea too. BTW, today's Super 77 isn't the same 3M 77 we used 20 years ago for foam core wings.

[Brent]

There is a special double sided laminating tape available that I used on my Apogee Saturn kits. I will have to see if the name is on the inside of the roll if there is interest. It was recommended in the Apogee instructions. I still have a almost a full roll. I have not decided on mine yet . Just opened the box to look at the parts.

[Crocodile]

On the Estes web site-----a discussion on attaching the SATURN V wraps.................

http://www.estesrockets.com/customer-service/faq/

[Molniya]

Thanks to all for the great tips !

3 light coats of 3M 90 sprayed on to the wrap from about 2 feet worked perfectly !

My little balloon trick does a great job of maintaining equal pressure too.

Thanks again !

[Flash]

Since the fins mount to the wrap, no doubt one would want to use the best glue possible when attaching the wrap. When I built the Apogee Saturn V one way they mentioned also was to wicker thin ca around the edges of the wrap.

I like the strength of the 3M 90 to. I'm going with the 90 and if needed, I will add thin ca on all seams.

[jeffyjeep]

Thanks to all for the great tips !

3 light coats of 3M 90 sprayed on to the wrap from about 2 feet worked perfectly !

My little balloon trick does a great job of maintaining equal pressure too.

Thanks again !
Thanks for doing these posts. I believe I'm now convinced to use spray adhesive instead of "The Devil's Mucous" (contact cement.)

[tbzep]

Thanks for doing these posts. I believe I'm now convinced to use spray adhesive instead of "The Devil's Mucous" (contact cement.)
I plan on using 3M spray but I have to give "The Devil's Mucous" it's due. My Centuri Saturn kit wraps are still solid thanks to the stuff. http://stratics.com/data/images/smilies/DevilSmiley.gif

[jeffyjeep]

Since the fins mount to the wrap, no doubt one would want to use the best glue possible when attaching the wrap. When I built the Apogee Saturn V one way they mentioned also was to wicker thin ca around the edges of the wrap.

I like the strength of the 3M 90 to. I'm going with the 90 and if needed, I will add thin ca on all seams.

Since the fins DO get mounted to the wrap, what is the general consensus for the best adhesive to use to mount the fins strongly to the wrap? Page 5 of the instructions says plastic model cement. Is there anything better, or is it already the best choice?

[LeeR]

Since the fins DO get mounted to the wrap, what is the general consensus for the best adhesive to use to mount the fins strongly to the wrap? Page 5 of the instructions says plastic model cement. Is there anything better, or is it already the best choice?

John Boren posted on TRF about building models for a trade show. He mentioned that on his LJII he used medium CA to attach the fins to the wrap.

[tbzep]

Lee, check your PM inbox. :)

[LeeR]

Lee, check your PM inbox. :)

Tim, many thanks ... Reply sent.

Everyone, nothing earth-shaking, just a request for a decal file ... :)

[mbauer]

3M 90 is rated as a high strength adhesive.

The last time I bought spray adhesive, all I could find I'd Elmers. I used it on my styrene wraps on the Estes Saturn 1B with excellent results.

I mentioned in another thread that Hobby Lobby carries both 3M 77 and Elmers. The Elmers was about 1/2 the price of the 3M.

I've used the elmers spray craft glue before. At first it works great, after a couple of years it dries out and the lamination came off in places. Not impressed. Always use the 3M Super 77 or the 90 now!

Mike

[LeeR]

Thanks for the heads up on the Elmers. Turns out I use spray glue in my wood shop for a several tasks that aren't permanent so I will likely just use it there.

[rocket.aero]

Check out Posts 13 & 14 in this thread over on the Other Forum for a brief overview of how the 3M High Strength 90 spray adhesive is used on the LJ kit:

http://www.rocketryforum.com/showthread.php?131767-Building-the-Estes-Little-Joe-II-Tips-Tricks-and-Modifications&p=1545261#post1545261

James

[jeffyjeep]

John Boren posted on TRF about building models for a trade show. He mentioned that on his LJII he used medium CA to attach the fins to the wrap.

It looks like I'll definitely be using something other than plastic model cement to attach the fins to the LJII wrap. I mounted all of the OTHER plastic parts to the wrap with plastic model cement and they sloughed right off. It appears that model cement isn't "hot" enough to weld through the wrap. I don't think I want to use Tenax7r and risk crazing the wrap, so I'll try the CA. If the CA tanks--at least I have debonder for it.

--but first I'll hit the wrap with steel wool to give it some "tooth".

[rocket.aero]

It looks like I'll definitely be using something other than plastic model cement to attach the fins to the LJII wrap. I mounted all of the OTHER plastic parts to the wrap with plastic model cement and they sloughed right off. It appears that model cement isn't "hot" enough to weld through the wrap. I don't think I want to use Tenax7r and risk crazing the wrap, so I'll try the CA. If the CA tanks--at least I have debonder for it.

--but first I'll hit the wrap with steel wool to give it some "tooth".

Strange, the plastic detail parts worked fine on my LJII kit with the use of Tamiya liquid cement. Any chance that the wrap was already primed and/or painted? That would certainly prevent the cement from working properly.

Tenax should work fine, although you should use a fine paint brush to apply the paint rather than use the fat brush attached to the bottle cap. Using the fine brush will allow you greater control over the glue application, which should prevent any over-application and surface crazing.

Hope this helps,
James

[jeffyjeep]

Strange, the plastic detail parts worked fine on my LJII kit with the use of Tamiya liquid cement. Any chance that the wrap was already primed and/or painted? That would certainly prevent the cement from working properly.

Tenax should work fine, although you should use a fine paint brush to apply the paint rather than use the fat brush attached to the bottle cap. Using the fine brush will allow you greater control over the glue application, which should prevent any over-application and surface crazing.

Hope this helps,
James

It does help. Thanks! I'll try the Tenax on one of the little strips first.