Optimal Building Procedure for LPR

[vsergeev]

Hello,

I've been reading this section for a while now, going a few pages back. There is quite a wealth of information here! My post-its were getting quite tired last night so I decided to hit the bed and ask the next day.

I've been following the common beginner building procedure (like typical estes instructions) with rockets, but now that I've been getting into building higher C's and D's rockets, I've decided that a bit more effort and support for my rockets might be better.

By effort and support I'm talking about fillets, fill n' finish for fins, super glue spread out over fins, sanding sealer, final coats over the paint, and possibly some epoxy near the fins. Stuff like that.

The building procedure that I follow right now is:
Follow instructions, apply glue fillets with wood glue on fins (usually in instructions anyway), prime with some generic auto-primer, paint. Pretty simple, eh?

I'm thinking of changing to a procedure like:
Follow instructions, apply glue fillets with wood glue (OR maybe epoxy if it's not over-kill), water down Fill n' Finish and rub over fins, sand fins, apply sanding sealer to fins, sand again, apply sanding sealer again, sand, prime rocket, paint rocket, and maybe put a final coat of Future or whatever last coat. I want the rocket to look really nice at the end.

What do you guys think of this? Is this too much for one rocket? Then again, you can never do too much for a rocket, can you?

BTW, I've got money to expand my building supplies so that's not a problem.

 

[SecretSquirrel]

Originally posted by vsergeev


I'm thinking of changing to a procedure like:
Follow instructions, apply glue fillets with wood glue (OR maybe epoxy if it's not over-kill), water down Fill n' Finish and rub over fins, sand fins, apply sanding sealer to fins, sand again, apply sanding sealer again, sand, prime rocket, paint rocket, and maybe put a final coat of Future or whatever last coat. I want the rocket to look really nice at the end.

If you use FnF, you really won't need the sanding sealer.

 

[flying_silverad]

If you are kit building, it might be cool to get into the habit of replacing weak recovery systems (shock cords) with a kevlar set-up. Get yourself a decent length of kevlar cord to keep on hand.

I am getting into the habit of using thin CA to coat fins and other balsa items prior final sanding/ and prior to installation of filling. Adds strength and and keeps application of "Fill and Finish" products to a min.

 

[OKTurbo]

Like Don said, if you use Fill-n-Finish you don't need another sealer. It is your sanding sealer. I've also used CA glue on the fin surfaces like FlyingSilverado says. It's works pretty good, plus it hardens the fins which is a plus, but it sure does smell when you do it. Watch out for those CA fumes....

Personally, I think epoxy for fillets would be overkill on a C/D sized rocket. When attaching fins it's important to rough up the surface of the tube where the fins attach. Especially when there is a glossy coating of glassine. Another trick is to make pin holes along the tube where the fins attach....when you glue on the fin, the holes will fill with glue and make tiny "rivets".

Getting a good finish is really a matter of trying a few things and seeing what works best for you. For example...I really like using Kilz primer. It's always worked great for me. I can spray it on thick and the rocket ends up looking great. Other guys have tried it and they don't like it at all.

Good Luck,
John

 

[lalligood]

My $0.02...

There are almost as many ways to build a rocket well as there are ways to build it wrong. I encourage you to experiment with different techniques--preferrably on different rockets or pieces of scrap so that you can truly see the difference between the techniques & form your own opinion of what works & what doesn't (for you anyway). Ultimately it comes down to 2 factors: 1) trial & error (aka 'experience') and 2) the amount of time you are willing to spend on the build. Typically, having more of #1 leads to a decrease in #2.

It just takes time to find what works for YOU. Having fun finding that recipe for success

 

[vsergeev]

Alright,

Thanks for the advice everyone. I'll probably try both FnF and the CA glue on the fins and see how it turns out.

I probably should install kevlar with the shock chords. I've been thinking about that for a while for the Estes rockets that just have a shock chord mount and shock chord (I've had it ripped off in a launch and I lost a nose cone because of it!).

I've heard many people on the forum swear by and have grudges against Kilz Primer. Like lalligood suggested, the only real way to know is to find out for myself.

I'll grab some extra CA, FnF, Kevlar and Kilz Primer and try em all out. Roughing up the tubes before gluing the fins is a good idea as well, I remember a thread about roughing up the whole body tube before priming for the best finish.

 

[flying_silverad]

Originally posted by vsergeev
Alright,

Thanks for the advice everyone. I'll probably try both FnF and the CA glue on the fins and see how it turns out.

I probably should install kevlar with the shock chords. I've been thinking about that for a while for the Estes rockets that just have a shock chord mount and shock chord (I've had it ripped off in a launch and I lost a nose cone because of it!).

I've heard many people on the forum swear by and have grudges against Kilz Primer. Like lalligood suggested, the only real way to know is to find out for myself.

I'll grab some extra CA, FnF, Kevlar and Kilz Primer and try em all out. Roughing up the tubes before gluing the fins is a good idea as well, I remember a thread about roughing up the whole body tube before priming for the best finish.

Kilz primer....I have heards some ups and downs on it but I can't find a decent hi-build primer and am thinking about giving it a try. Do you guys have any tips on using this stuff?

 

[OKTurbo]

No real tips John. I just spray it on. I usually let it dry for a day....12 hrs minimum before I sand it. If you try to sand it too soon it will just load up the sandpaper. When it's dry it sands nicely (dusty).

I have noticed that the first coat usually bubbles up on some places. I'm not sure exactly why...maybe finger prints...maybe glue. When it dries the first time I sand down the bubbly parts. The second coat has always covered good for me. Two coats has always been enough for me.

On my recent LaserX build I used Kilz spray primer (2 coats) without any other filler like Fill-n-Finish and the Kilz filled the grain just fine...although the first coat took a bit more sanding. It's kind of a trade off. You're either sanding F-n-F or you're sanding Kilz. For me, it's easier to spray the Kilz on than it is to mess with the F-n-F.

 

[jpasqual]

vsergeev
couple more ideas for you to try - soak bt ends and engine mount with CA - will make your rockets last longer
- warm up you can of spray paint for about 10 minutes in warm water and shake can continuously - this will help with a more smoother shine

 

[vsergeev]

Thanks for the tips, I'll be sure to try the first one.

I haven't had much trouble with spray paint, but if I ever do I'll try the warming up stuff you mentioned.

I got some FnF, but am still looking for the Kilz Primer, and will probably get the kevlar from Thrustline

First, I'm going to try the CA-On-Fins and your first tip..

 

[lalligood]

Kilz is normally not placed on the shelf with "standard" spray paints--mostly because Kilz is anything but standard!

At your local Wal-Mart, look for the 1 gallon cans of Kilz...you'll find the spray cans hiding somewhere nearby

 

[vsergeev]

I'll try to find it at Walmart when I have the time to go there.

Thanks, for the tip.

So far, I've CA-coated 2/4 fins of my Deuce's Wild (I decided to only do two at a time because the fumes become an annoyance even with the fan and window opened). However, the fins do turn out nice and strong. Also, I coated the end of the motor mounts and motor mount holder with CA. BTW, for CA I'm using Krazy Glue, and I hope that's good enough.

 

[moocrew]

**NOTE: I would only take these suggestions if you aren't concerned about getting alot of height from your roc.


my technique....
1. Overkill on all construction
2. Overkill with sanding and priming
3. Spend three weeks contemplating paint scheme.

I do over kill mainly for appearance launching my birds to the moon isn't on the top of my list. So finishing techniques are my thing.

Ill use epoxy on Quark sized or swift 220 sized rocs just to get that nice "smooth" corner look. Then ill go over the fins with thin CA usually twice... (apply..sand..apply another coat...sand..prime)
I also do as jpasqual mentioned and dip or coat the BT ends And i beef up the recovery just for fatigue issues with the cords and 'chutes and such.
I also usually beef up the motor mount. spraying the inside of the roc with some type of flame retardant paint is common practice to me (keeps your insides for getting chared out of your butt.) Elmers (white) glue works inplace for good fillets just take a bit longer to set than epoxy.

I don't really overkill but i do put alot of time into finishing and "bulletproofing" sometimes more than I need but hey its what works for me.

Just find you're style and stick with that.
You can't really do anything wrong.......unless you do something dumb
lol

Good Luck!

-moo

 

[vsergeev]

I'm pretty much for altitude, but I'll probably do some overkill as you suggested for rockets I truly want to look good.

What CA do you use?
I just ran out yesterday. Is there some special brand that's sold in a large volume or something?

 

[moocrew]

I bought mine at a local hobby shop. Dunno if any big stores have it...you could make some calls around your area chances are someone carries it. If not you could order online.

I don't think that any one brand of CA is better than the next..im not sure.
But i do know that there are three different viscoties (spelling?) and they are.....
light
medium
thick .....something like that.

Light dries or "sets" almost instantly...i wouldn't recommend this unless you are just tacking things in place... the light kind isn't very strong.

Medium will be alright for most things no real great attributes to it.

Thick takes the longest to set but is typically the strongest.

Ill also mention that even though thick and medium can be used to fill gaps...the gaps can't be very large the larger the gap the less strength the CA has.

for LPR its probably a good choice to go with Thicker CA and fill gaps with some type of fill n' finish i assume.

CA can be tricky..just experiment with it...just don't glue your hands together..or fingers for that fact.

-moo

 

[moocrew]

** I don't really suggest Overkilling everything..or anything for that matter...just do what makes your roc look good.

 

[moocrew]

** I don't really suggest Overkilling everything..or anything for that matter...just do what makes your roc look good.

 

[arthur dent]

There is no doubt that doing all of the above will make your rockets look fantastic