Author Topic: Jart/Silver Bullet Rebuild  (Read 707 times)

Offline mdutch

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Jart/Silver Bullet Rebuild
« on: September 10, 2016, 10:42:11 AM »
OK, so at LDRS 31; Tim Lear had a small Jart special sale where if you bought the kit and came back the next day with it built and ready to fly he gave you a CTI three grain case and load to fly it with. It is an all fiberglass kit with a 2 1/4" air frame 12" long, ( it's basically a 54 mm motor mount tube), 1/16" fins and centering rings and a 29mm fg motor mount, it also came with a plastic nose cone. If I remember correctly it sold for about $35. I paid a little extra for the Aero Pack retainer that fit it, but the deal was more than worth it, and yes I did bring it back the next day completely built and got the motor case and load too.
Believe me as I was the Launch Director for the event, even I was amazed that I had it finished.

Well after I painted it chrome the name, "Silver Bullet", seemed to fit it, so that's what I called it. And no, I really don't drink Coors that much. I flew it a half a dozen times but stopped after the second fin started to come loose. Evidence of just how too quickly I built it in the first place.

So yesterday I picked it up off my 'rockets to be repaired' bench and decided it was time to fix it. Both loose fins popped out easily and the third fin came out with a good rap down on the edge of my bench. I was able to pop the motor mount and centering rings by using a 2" diameter dowel and then got the centering rings off, all with out any damage. The only thing that I left on was the Aero Pack retainer as I at least did use JB Weld to mount that. I also replaced the 1/4" scorched and frayed flat Kevlar with some 1/8" round Kevlar so I would have more room for a bigger motor.

After sanding everything down to remove excess epoxy I started to put it all back together this time using JB Weld for everything.
In the photo you see the fins, the airframe, and the nose cone along with the motor mount assembly ready to be epoxied back into the airframe. The rectangular hole you see in the bottom of the nose cone is for my tracking transmitter. With a rocket this small, I want to get it back!

I will post a few more photos as I continue and finish it.
« Last Edit: September 11, 2016, 08:14:18 AM by mdutch »
Mike Dutch
TAP  L3CC
URRG & MRSI Founder
"I just Want to Fly ROCKETS"

Offline mdutch

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Re: Jart/Silver Bullet Rebuild
« Reply #1 on: September 10, 2016, 01:26:50 PM »
So now I have the motor assembly in and I'm ready to start epoxying and mounting the fins.
I'll start by applying a good bead of JB Weld to the fin root and then I'll slip on the fin guide to keep everything in place until it dries.
Mike Dutch
TAP  L3CC
URRG & MRSI Founder
"I just Want to Fly ROCKETS"

Offline mdutch

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Re: Jart/Silver Bullet Rebuild
« Reply #2 on: September 10, 2016, 01:34:36 PM »
So here you see all the fins in and held in place with the cardboard fin jig until the epoxy sets. While I was at it I used the remaining epoxy to apply a very fine fillet to each side of the fins. I'm not expecting this to be the final fillet but what the hey, it can't hurt. The holes you see in the airframe are where the rail buttons where and they will be reinstalled as the last step when it's all repaired and painted.
Mike Dutch
TAP  L3CC
URRG & MRSI Founder
"I just Want to Fly ROCKETS"

Offline mdutch

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Re: Jart/Silver Bullet Rebuild
« Reply #3 on: September 11, 2016, 08:28:21 AM »
So here you see the rocket all taped and ready to apply the fillet. I like to use US Composites epoxy mixed with some white micro balloons. I'll use the large "popsicle" stick to spread it down the fin joint and then smooth it out by dipping my finger in the rubbing alcohol and wiping it down the fillet.
« Last Edit: September 11, 2016, 08:30:15 AM by mdutch »
Mike Dutch
TAP  L3CC
URRG & MRSI Founder
"I just Want to Fly ROCKETS"

Offline mdutch

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Re: Jart/Silver Bullet Rebuild
« Reply #4 on: September 11, 2016, 08:36:24 AM »
Once I'm done applying the fillets I will carefully put all of the tape off and then let it sit just long enough for the fillets to cure to a tacky feel and then I smooth them out once more with my finger and rubbing alcohol. Doing this will smooth down the edges so there is little to no sanding needed.
Mike Dutch
TAP  L3CC
URRG & MRSI Founder
"I just Want to Fly ROCKETS"

Offline RKeller

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Re: Jart/Silver Bullet Rebuild
« Reply #5 on: September 12, 2016, 12:06:20 PM »
lookin good Dutch, I've always like the Jart, cool little rocket.
Riley Keller
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L1 25 Oct 2014 Estes MDRM CTI H133
L2 25 June 2015 Rocketry Warehouse DYOK, CTI L1030RL 14.7k ft mach 1.57

I'm addicted to building stuff, rockets are just a way to get high