Madcow 2.6" fiberglass Patriot build

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matthewdlaudato

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This will be a short and straightforward build and thread. I got this off the Madcow July 4th sale, just getting around to building it. Will be stock build, Aeropoxy adhesive, JB Weld for the retainer. Parts will get cleaned with denatured alcohol and roughed up with 180 grit sandpaper before bonding.

Here's what's in the bag:

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The forward centering ring curing on the motor tube. Those are two spent 9v batteries that I'm using for support & alignment. And why not.
 
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Ready for installation. That's a temporary centering ring cut from foam board to keep the tube centered while the forward ring cures.
 
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Motor mount installed, ready for fins.

Did you attach the shock cord already? Or at least a string to pull the final shock cord through the eye bolt? With the minimum clearance on that eyebolt, you won't be able to attach a quick link. It will be tough to get a shock cord threaded through it too.

Don't ask me how I know that.
 
It is already attached and stuffed into the tube for safe keeping. (I have a guess as to how you know that - bit me on a recent build but was able to work around it!)
 
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Two down, two to go. I smooth out the excess Aeropoxy and dab in more as needed to make the fillets. I won't need to do any additional fillet work (other than perhaps some Bondo to smooth them out for painting) so this saves some time in the build.
 
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The last fin, installed and curing. Alignment looks good, all fins solidly mounted with good internal/external fillets.
 
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The bulkhead is assembled but needs some sanding to fit into the nose shoulder. Will probably hand sand it.
 
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Packed chute, cord, protector, and simulated mass of an H143 (largest likely motor). Epoxied in 230g of nose mass in the form of 13 bolts to get CG at recommended location. Only thing left to do is epoxy the nose bulk plate in place.

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Closeup of the nose mass. Those tiny fins combined with dense fiberglass aft necessitated quite a bit of mass to push the CG forward.
 
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Aft centering ring and nose bulkhead epoxied in place. Will put fillets on both later today.
 
I use it in several ways - sometimes clamped to a bench with the tube on the side, fin parallel to ground. In this case I happen to use it in upside down mode. The jig has a 45° V that the tube fits snugly into, the bungee assures that. I do throw a level on it in this mode to keep it plumb.
 
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Put the epoxy fillets on the aft ring and nose bulkhead. Down to retainer and rail buttons, then the long wait until spring for the finish prep and painting.
 
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Back to this build now that spring is here. Mounted the rail buttons with a dab of 5-min Loctite on the screws. Used hack saw blade taped to a ruler to reach in and cut the protruding screw tip. Will dab on some epoxy to smooth it out.
 
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