New to Mid Power Rocketry

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The retainer is usually the last thing you glue on.

This way, the rear-most centering ring can be placed / positioned to help get things aligned. Then it is removed to apply internal fillets. Then finally glued in place. Then glue on the retainer.

But this is how we all learn! :D

Another helpful hint:
If you are using buttons, add a piece to the centering rings, another piece of 1/4" ply or... Sand to match the CRs! Align them when you glue the two CRs onto the MMT tube. Then mark off on the BT where these will be located in the BT. Once it is all together, you now have two 'thick' points to mount your buttons. Drill your holes, then use wood screws to mount them buttons! No need to futz with blind nuts or ..
Ill have plenty of room for fillets internally and on the rear.
 
Well the Lil Goblin is finished.....ish. Just have to finish fillets in the morning sand. And then its ready for primer and paint. Came out wonderful. Not bad for my first mid power. This makes 4 rockets to paint and 6 to fly.
 

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For tacking fins in place I use JB Quick Weld. 6 minute set time and it's heat resistant up to 200*.
Is this for the joint between TTW fin and motor tube? I'm getting ready to attach fins, and I'm planning on Elmer's Carpenter's Glue for the fin root to body tube (double gluing), and TTW tab ends to CRs, but can't decide between J-B Weld or 30 minute epoxy for the fin to motor tube joint. I like the heat resistance of J-BW, but is it as strong as epoxy? Or, for this purpose, does it need to be?
 
Is this for the joint between TTW fin and motor tube? I'm getting ready to attach fins, and I'm planning on Elmer's Carpenter's Glue for the fin root to body tube (double gluing), and TTW tab ends to CRs, but can't decide between J-B Weld or 30 minute epoxy for the fin to motor tube joint. I like the heat resistance of J-BW, but is it as strong as epoxy? Or, for this purpose, does it need to be?
I put the JB on the bottom edge of the fin root for TTW fins. Then press it down on the motor tube. Lift a little and press it down again. I use a fin jig and do all four fins at once. Only takes a minute or two. The jig holds the fins in place at the correct angle and perpendicular to the motor tube. It sets in 6 minutes and the fins are locked in place. Then I proceed with the external and internal filets. I finish by epoxying the rear CR into place.
I would say it depends on how heavy the rocket is or how fast it's going to go weather to use wood glue or epoxy. I think the biggest advantage of epoxy over wood glue is epoxies heat resistance.
 
@teepot - I'm using both wood glue and epoxy—wood glue on fin/body tube and centering ring joints, and epoxy on the fin/motor mount joint. I've decided to use JB rather than regular epoxy, just because it is stiffer, and can be applied to the edge of the fin tab and inserted through the fin slot without dripping.

The rocket is 24 oz with a G80 loaded. OR sims that motor at 375 mph, 15 Gs.

Fin Template.jpg
 
@teepot - I'm using both wood glue and epoxy—wood glue on fin/body tube and centering ring joints, and epoxy on the fin/motor mount joint. I've decided to use JB rather than regular epoxy, just because it is stiffer, and can be applied to the edge of the fin tab and inserted through the fin slot without dripping.

The rocket is 24 oz with a G80 loaded. OR sims that motor at 375 mph, 15 Gs.

View attachment 471260
Looks good to me. Your speed and G force are not that high.
 
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