Estes V2 #3228 fin mounting improvement
 

"The Vixen" left for Philly on Monday--leaving me all alone.

Ever since the V2 kit was re-introduced I've been brainstorming about a way to make the joint between the slot-mounted fins and the engine tube more secure, and I think I've nailed it. It's all about having access to the joint after the fins are inserted into the slotted fin can. TBC

I first assemble the engine tube and engine mount as per the instructions except I don't mount the (2) CR8050 rings. I take one of the rings and using the nibs as guides, I pencil a cross on it. I then use a pair of battlefield tracheotomy scissors (yes, really) and I cut (4) curved wedges out of the ring. Next I insert a tube marking guide into what will be the forward end of the engine tube and make (4) fin lines with the mount's EH centered between two of the lines. Some of you may have figured out already where I'm going with this. TBC

Next, I epoxy the rear CR onto the rear of the engine tube and the large CR that I modified earlier onto front of the engine tube--but 1" further toward the (ejection) end than the instructions call for. TBC

Next, I prepare the fin can.

After cutting the raised nibs and the top and bottom scrap pieces from the fin can with a razor knife and preparing the slots to accept the fins, I sand some "tooth" into the inside rear end of the can with 220.

I then insert the engine tube assembly into the can as far as it will go--registering the small CR onto the inside sanded area and orientating the EH between (2) fin slots. I then use a short scrap piece of BT to align the modified large CR and the can's shoulder. I then glue the small CR to the inside of the can with epoxy. TBC

Now with the scrap piece of BT80 removed from the fin can, The engine mount tube is perfectly centered in the fin can and the joining areas of the fins' root edges where they register to the engine tube are accessible through the wedge-shaped cutouts of the large CR. TBC

Now for the internal gluing operation.

After first mounting (2) of the fins and cross-bracing them for alignment until the wood glue sets, I then use a long stick to apply epoxy onto the fin-to-engine tube joints.

After that epoxy hardens I repeat the procedure for the other (2) fins,

.....and voila!

The V2 has (4) Amatol-proof fins!

Now that the internal epoxy is hardened I attach and epoxy the top CR to the engine mount tube.

Before inserting the assembly into the BT80 I do a couple of upgrades: a 100# Kevlar shock cord leader and a 48" braided elastic shock cord.

I then epoxy the engine tube/fin can/fin assembly into the BT80 and the V2 has fins I won't have to worry about!

Now the build gets continued and completed like usual.

Time for a Scotch and a Wingwalker. Good night.

I like it. That is how the kit should have been from the factory.


Bill

I agree. Nice work-around, jeep.

Thanks. But IMO if the kit had been like that from the factory, I think it would have put the skill level so high that it wouldn't sell well. Even with my skills the technique is sorta kinda difficult and potentially messy, but the results are MORE than worth it, and this is how I'll do the fins on all future V2's.

The real test will be a rough flight and a hard landing!