Internal filet epoxy recommendations

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Locksmith

Locksmith

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I have 2 rockets on the bench and they are all have the wings "tacked" on with JB weld which I love working with but just a little to thick for this. This time I left the bottom centering out so I could do internal filet but their is just no room 1 is 3" rocket 1 is 4". The 4" I am able to use the JB weld just not sure what to use on the 3".
Any recommendations? needs to be high heat since it will be attached to motor tube, and able to "flow from the end to the top. Foam Maybe?

Not afraid to order what I need rather do it right first time.

Epoxies I have on hand
BSI 5m-6m-30m
Rocket Poxy
JB Weld
635 thin epoxy resin - Also have milled fiber and shredded carbon fiber additives Never used any of it.
Elmer's regular and Max
Gel Superglue

Thanks for help
 
You did not specify a material. If it is wood and paper, just use wood glue. The MMT does not get hot enough to be an issue. I have used BS epoxy on fin roots with no problem. If you are worried, some folks here use West Systems (or similar hi end product) with milled fibers.

There are myriad of methods you can use to get the glue up inside the tube. I am partial to bamboo skewers from the grocery store with a q-tip taped to the end. Coffee stir sticks (or craft sticks from the store) work well, again can be taped to a skewer as needed for reaching in. Syringes work well if you have room (https://www.amazon.com/gp/product/B01N3KPB2P/?tag=skimlinks_replacement-20 ) they can also be used to inject glue through openings cut/drilled in the airframe along the fin root.

Keep it simple, as a general rule, with proper surface preparation, your glue joint will be stronger than the materials being joined. JB weld is only necessary for attaching motor retainers.
 
Last edited by a moderator:
T-Rex said:
You did not specify a material. If it is wood and paper, just use wood glue. The MMT does not get hot enough to be an issue. I have used BS epoxy on fin roots with no problem. If you are worried, some folks here use West Systems (or similar hi end product) with milled fibers.

There are myriad of methods you can use to get the glue up inside the tube. I am partial to bamboo skewers from the grocery store with a q-tip taped to the end. Coffee stir sticks (or craft sticks from the store) work well, again can be taped to a skewer as needed for reaching in. Syringes work well if you have room (https://www.amazon.com/gp/product/B01N3KPB2P/?tag=skimlinks_replacement-20 ) they can also be used to inject glue through openings cut/drilled in the airframe along the fin root.

Keep it simple, as a general rule, with proper surface preparation, your glue joint will be stronger than the materials being joined. JB weld is only necessary for attaching motor retainers.
Click to expand...

+1 on all this!

BS epoxy (30 minute) placed in globs, then hit with a heat gun / hair dryer will make the epoxy runny & flow evenly. It'll also cure faster...
 
Last edited by a moderator:
I've been using straight Gorilla Epoxy almost exclusively since I BAR'd. Readily available and thus far seems plenty strong. My L1 PML Ariel is built with it. That said I haven't pushed mach yet...low and slow has been my thing so far...
 

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