Gemini DC Paint/Glue Dilemma

[Pippen]

My 11-year-old son is working on a Gemini DC for a 4-H project. You've already talked us through the crushed body tube and that turned out well and we now have one more spot I could use some advice on. I wish I'd found this place earlier but that's besides the point now.

This rocket has two small side pods for rear deploying parachutes and when it came to attaching the pods and painting we were in a catch 22. If he attached the pods on prior to painting there was no way he could get spray paint into that small area between the pods and fins. I don't know if it was the right thing to do but we decided to paint first and then attach the pods. I had read elsewhere of someone doing this using epoxy with satisfactory results but now as I read through the epoxy threads it sounds a lot more difficult than we bargained for. I'm glad for us to learn something new but I don't want to risk blowing it so close to the end, especially since this needs to be checked in on Monday evening.

So this is where I could use your ideas to strike a balance between getting this to look decent and adhere well. Would you use glue? Epoxy? If epoxy is there any brand that would be easy for rookies? Adhere it well enough to get through the fair and then strengthen it later? I'm assuming he needs to do some sanding where the pods need to be attached.

While I'm at it I'll ask if anyone has advice as to how to get around this problem if we run into something like this again.

Thanks,
Pippen

 

[Justin Horne]

All epoxy is just about equally simple.. Most is a 1 to 1 mix, and the stuff that isn't is WAY WAY WAY past what you need... Also, I don't think you need epozy at all for an estes kit... It seems like overbuilding.. However, on the pro side, you can get epoxy that dries in a variety of times, that would make building easier..

 

[rbeckey]

At a home improvement store you will find epoxy in a dual stringe. You push the plunger in and a premeasured amount of each component comes out. You mix it thouroughly with a coffee stirrer or popsicle stick or what-have-you, and you have about as many minutes as it said on the package to get everything where it needs to be.
Sand the paint in the area to be glued. Use masking tape to keep everything clean. Stick the tape to the inside of your arm first, to reduce it's tack and reduce the chance of pulling up some paint when you peel it off later. Mask off a thin strip and sand to the tube on both parts. Mix the epoxy just before you intend to use it, AFTER the sanding is done. A little goes a very long way. However much you think you need, use half of that. Seriously.
Next time you find yourself in this quandry, cut a thin strip of masking tape and put it on the tube before painting. Completely finish the tube and pull the strip off. Instant glueing area. This is how I intend to finish my Outlander.

 

[qMaxx]

Just a suggestion, but you will probably want to scrape any paint off the areas that will be glued or epoxied. Continue the scraping and/or sanding through the glassine finish on the tubes as well. That will allow whichever adhesive you use to soak into the parts and give a good strong bond. Next time, mask off the areas to be glued before painting - this was a step in the instructions for both the Estes 1/100 scale Saturn 1B and the Titan IIIE.

Edit: Darn, Bob. Just 2 minutes sooner....

 

[Pippen]

Masking off the area...now why didn't I think of that?

He's only got a coat of primer so I think this should do it. Barring any unforseen problems, that is. Last year it was the shock of watching the paint on the rocket crackle when the second coat went on (unbeknownst to us) precisely when the solvent of the first coat was evaporating. The year before it was discovering that metallic gold is NOT the color to choose for a first year project. Next year, who knows...

Thanks a bunch.

 

[Justin Horne]

Originally posted by Pippen
Masking off the area...now why didn't I think of that?

He's only got a coat of primer so I think this should do it. Barring any unforseen problems, that is. Last year it was the shock of watching the paint on the rocket crackle when the second coat went on (unbeknownst to us) precisely when the solvent of the first coat was evaporating. The year before it was discovering that metallic gold is NOT the color to choose for a first year project. Next year, who knows...

Thanks a bunch.

Im assuming the gold shows EVERY little imperfection, right? welcome to true rocketry...:kill: I've gotten way too used to that...

 

[Pippen]

Originally posted by Justin Horne
Im assuming the gold shows EVERY little imperfection, right? welcome to true rocketry...:kill: I've gotten way too used to that...

Yup, you got it. And as an added bonus, it has superb fingerprint enhancing properties, ideally suited for 9-year-old boys and their younger siblings.

Thankfully, painting and fin alignment are in his father's department. I get to watch over the rest.

 

[Pippen]

My son picked up a Best of Class for his rocket at the fair today! He felt it was worth all of the effort (sweat and a few tears too) in the end and was so excited for his to be selected. I am seeing a competitive side to him I've never seen before as a result of this and last year's placing: he has his sights set on making it to the State Fair next year. As for me, I just have my sights set on recovering from this year's fair.

I sincerely want to thank all of you who gave us suggestions to consider when we came to the bumps because without them we would have been going at it blindly. My husband was his small town's rocket medalist when he was a kid and in my before kids days I was a science teacher so he has willing help--it's just not the knowledgable help of people who have their hands deep into it now.

Our Introduction to Epoxy 101 was a bit stressful but given we were approaching the nth hour I think it was the right thing to do. When he had it all ready to go he looked at me and asked "Are you sure you know what you're doing?" to which I replied "No, but we're doing it anyway."

Lessons we learned:
1) It doesn't take a whole lot of epoxy
2) If you run short of epoxy don't add more because the whole mess starts to harden
3) It would be prudent to learn how to thin down epoxy that is getting too thick before digging in
4) When it's way past bedtime, kids should be sleeping and epoxy should wait until morning because that's when epoxy smudges are likely to happen

There was one minor thing we ran into and for future info was wondering how to solve it. A small short horizontal vent tube connects the BT to the side tubes. One of those side tubes fit perfectly and was flush with the side. The other side tube fit fine into the vent hole but it didn't lie flush with the rocketnear the top. We knew it was there before he attached them but I assumed the epoxy would be enough to bring it together and close the gap but it wasn't. The gap wasn't huge and it was filled with epoxy but the two didn't match perfectly. I know this is nit picking but how could this have been fixed? Is there a way to clamp gently without damaging the tubes?

Again, thanks a million!
Pippen

 

[Missileman]

I am glad to hear of your sons placing and his interest in the hobby.
A strip of masking take is about the best clamp in this situation.
Most epoxies can be thinned slightly with a little denatured alchohol.
When you fly the DC be careful you don't put recovery wadding too far into the side pods. It will block the cross tubes and prevent deployment.(I learned this the hard way)

 

[rbeckey]

Epoxy can be wiped up before it sets by rubbing alcohol. WalMart sells a 90 percent solution that works well. I use wax paper for a disposable work surface. Epoxy does not stick to wax paper. Epoxy should be handled with gloves. It can cause a serious allergic reaction on bare skin. Dry fit all parts before mixing epoxy. 5 minute epoxy is of limited utility to persons who need extra time to figure out what's what. Other adhesives may be a better choice. Wood glue can cause problems as it shirnks when it cures. Polyurethane glue expands as it cures and should never be use on surface mounted parts. Buy a couple of inexpensive rockets and build them using various techniques. By the time next year's project is due, you'll be ready.

 

[Justin Horne]

But are you ever gonna FLY THEM?!?

 

[Pippen]

Originally posted by Justin Horne
But are you ever gonna FLY THEM?!?

WHAT'S THIS??!! And risk denting those fins and ruining that paint job?

Yeah, it's gonna fly. First time out will be the last day of the fair. They invite all the kids to a launch and they can try out their projects and bring rockets from home. They have a big bucket of engines and they go to it. They have a ball--much more fun with friends than mom or dad.

 

[Justin Horne]

I say get an 18mm Aerotech reload kit to let it get some SERIOUS altitude...

 

[seo]

Did you take any pictures that you can share?

 

[Pippen]

Tee hee, Justin! We'd get some serious altitude all right...right before it was lost forever in a cornfield.

Seo, it's still on display and I can't get close enough for a good photo but afterwards I'll try and get that posted. I really enjoy seeing pictures of everyone's rockets.

Thanks all for the additional tips.

 

[Justin Horne]

Originally posted by Pippen
Tee hee, Justin! We'd get some serious altitude all right...right before it was lost forever in a cornfield.

Seo, it's still on display and I can't get close enough for a good photo but afterwards I'll try and get that posted. I really enjoy seeing pictures of everyone's rockets.

Thanks all for the additional tips.

I know, I know... I just like seeing them fly! Although, coming from your perspective, I have lost (well, actually, sent to my repair desk) a couple models that looked awesome, so I can easily know what you mean..