PML D Region tomahawk fin fillets

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highflyer1968

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I'm just wondering if anybody can tell me what the best way to fillet the fins inside the body tube and to the motor tube. I'm using jb weld as the epoxy and its not really that runny and with such a small space it seems like it will be hard to not make a mess inside. Any help would be great.
 
Go to a hobby store and pic up some Bob Smith Industries 30-min Slow Cure epoxy.

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Hobby Lobby or similar craft store should carry some. In a pinch, this epoxy has built many a fillet on my rockets.
 
will his bob smith slow cure epoxy take the heat from the motor. I have been told jb weld is good for that but just has to be something better then a stick trying to place the epoxy in the side the body tube for the fillets
 
SEE sticky at top of this high power section page. " How to build DarkStar" etc.
Go to inject internal fillets in index.
Just about any basic build questions can be found there in index.
 
I leave off the aft centering ring then apply my adhesive to a dowel of the fillet size I want. Then roll the dowel into the joint leaving the glue and a decent fillet.
 
JB Weld will work just fine.
It can take the heat. BSI Epoxies become rubbery when they get hot.
 
JB Weld will work just fine.
It can take the heat. BSI Epoxies become rubbery when they get hot.

How much heat and for how long is the question. BSI can take some heat, as I have rockets built with this epoxy that are 18-years old. I do not use BSI epoxies much any more, except for the 5-Min for tacking fins onto motor tubes, as there are far more superior products on the market. But in all the rockets I have used the epoxy on, none have failed epoxy fillets, as the heat is just not present long enough for structural failure. For heat, there is no doubt that the JB Weld is superior... like any viscous material, epoxy included, it just takes a little finesse to make Purdy fillets.
 
JB Weld is also a joy to sand, so it is fun and enjoyable to work with.
 
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