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zeke1312
10-29-2006, 10:45 AM
I'm new at rocket building and would like suggetions on what type of glue to use for construction. Different glue for different parts of a build? Some reasons for one glue type over another? What about body filler?

barone
10-29-2006, 03:13 PM
For general construction, I use white glue. Either WeldBond or Titebond. Elmer's is good also. Just don't use too much. It could shrink on you and make your body tubes look really bad. A yellow carpenter's glue is also used by a lot of rocketeers. Most kits will give a recommendation on glue. Plastic parts usually use a CA adhesive or model cement. Again, the kit should provide some type of recommendation. Higher power stuff and you start looking at using epoxies. I like to use the 5 minute ones because I don't like to sit and wait for it to dry. Normally, the longer the cure time, the higher the strength.

Most of us, I say most based on past post, use Elmer's Fill and Finish for body tubes spiral filling. It's porbably listed as wood filler at the store. Just water it down some and smooth it into the spirals on body tubes or work it into the grain on balsa parts. Some people brush it on but I just like to make a mess and use my finger to push it into the grooves and grains. Need to sand it before you paint and apply some primer (depending upon on how detailed a finish you want). A good sandable primer like Krylon or Kilnz works well. Some folks prefer the Kilnz because it seems to go on thicker, thus filling with fewer coats.

Good luck with your efforts. Remember, if you need help, these forum members have a wealth of information that can be tapped. Also, check out the construction tips at this web site, http://www.apogeerockets.com/education/construction_tips.asp. There're other links there to other places with some more tips for you.

CPMcGraw
10-29-2006, 05:05 PM
Zeke,

Welcome to Model Rocketry Construction 101... :D

For general construction, I use white glue. Either WeldBond or Titebond. Elmer's is good also.

I've also used several brands, but I keep coming back to the Titebond II formulation for general construction. This is not a "white" glue, but a standard "yellow aliphatic resin" woodworker's glue. With either white or yellow, there is a bit of shrinkage, and sometimes this is most-noticeable around the engine mount components.

Barone mentions CA and epoxy glues, and these do have their place. They also have their weaknesses. CA, for example, is great for sealing paper skins to balsa fins, and for making or repairing balsa-to-balsa joints; but it is poor to unusable for attaching fins to tubes. Epoxy is heavy, but is good for attaching paper tubes to plastic fin units if used sparingly (and correctly - thin smears on both mating surfaces). For assembling polystyrene parts, I prefer Plastruct (orange bottle), but Testors clear liquid is a suitable alternative. There is also a thicker gel-type from Testors that comes in handy.

Most of us, I say most based on past post, use Elmer's Fill and Finish for body tubes spiral filling. It's porbably listed as wood filler at the store. Just water it down some and smooth it into the spirals on body tubes or work it into the grain on balsa parts. Some people brush it on but I just like to make a mess and use my finger to push it into the grooves and grains. Need to sand it before you paint and apply some primer (depending upon on how detailed a finish you want). A good sandable primer like Krylon or Kilnz works well. Some folks prefer the Kilnz because it seems to go on thicker, thus filling with fewer coats.

I like both Fill-N-Finish and Kilz, and alternate between both. FNF is very good in repairing dings (like the infamous Estes Dent) and in filling spiral grooves in tubes. Kilz is great because it's quick and easy to apply, but it has its drawbacks, too. If applied from the spray can too heavily, it will bubble on the surface due to trapped gasses. These bubbles will not rise to the surface before the spray coat dries, and it resembles the surface of the moon after you've sanded it down. If you have the time (and the equipment), buy the regular pint or quart can and apply it in light coats with a spray gun / detail gun.

Good luck with your efforts. Remember, if you need help, these forum members have a wealth of information that can be tapped. Also, check out the construction tips at this web site, http://www.apogeerockets.com/education/construction_tips.asp. There're other links there to other places with some more tips for you.

...And we'll butt right in without you having to ask, too! :D :rolleyes: You'll find most of us on this forum are builders to one degree or another, so we really enjoy sharing our thoughts / tips / opinions on the subject of rocketry.

zeke1312
10-30-2006, 09:25 AM
Thanks for the replies! I must confess of recently building (well almost complete) a TLP Nike Ajax. It's the first rocket I built since the mid '70s so I figure for sure I'm a novice! The NJ is complete to the point where I'm priming the rocket. Now I can notice "imperfections" in the finish. One thing I found hard to work with is CA. I followed instructions and began with "fast" CA. The stuff dries quickly and I've found it hard to eliminate runs and roughness when spreading with a business card. Sanding becomes a chore since the stuff does not take to sanding easily. Some areas near the larger body fins have imperfections or gaps at the joints ( I used Elmer's White). I assume I can/will fill with your recommended wood filler so that should not be a hard one to overcome. I guess to overcome the CA induced imperfections I'll just continue to sand.

I've used 3 coats of Krylon primer. I plan to use Krylon satin for the finished surface. How well will decals adhere to the satin surface?

Otherwise the NJ looks great. I built and have the Estes version in the mid 1970s and like the comparison of size and features. Actually the Estes has farily good detail!

I want to build a Nike Hercules (I'm hung up on the Nike thing), but apparently there is no kit. I did see scale plans to build one (Apogee I think). I'm not adverse to building from scratch but am wondering how good such drawings are.

Now that I have tackled the TLP Ajax, can I assume using good drawings I can build from scratch? The TLP has fair instructions which have you cut fins (15) and make conduits. The body tubes, interconnect tubes or whatever you call them, the nose and motor mounts came "precut". When ordering tubes and the various fiber rings, are all these things "stock" . I assume I would need to cut tubing to size but body rings would be a task for me. The other stuff (fins, etc) I have no problem with.

Thanks

ghrocketman
10-30-2006, 10:54 AM
I use 4 glues for about 95% of all my low/mid power model rocket construction.

1) Titebond II :for general construction and attaching fins to body tubes.

2) 30 minute Epoxy: for ALL fin filleting for anything that is 24mm engine and above, and any 18mm that I use my RMS18 (composite reloadable)engine in. I know it is heavy, but the weight penalty is very small if used sparingly...the fillets come out perfect in one step, every time. I have in fact started to use this method on ALL my rockets except 13mm powered, even though the strength is not needed. One benefit of this is that I NEVER get fins busted off upon landing.

3) Medium CA: Wherever specified in the instructions of particular kits.

4) 5 minute Epoxy: for building/installing ALL engine mounts that will or potentially will use composite propellant engines (RMS24 & RMS29)

I use several other adhesives, but the above listed are used for 95% of all jobs.
For plastic parts I use Tenax 7R liquid plastic welder if the parts fit tightly, and I use Testors tube-type plastic cement thinned with 30% Toluene for parts that do not fit tightly.