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LOC/Precision Vulcanite H76

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DynaSoar

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Why yes, as a matter of fact I was a busy boy this weekend.

As best as I can tell, this is an upscale Weasel. Not that that's a bad thing. It's a good design. It's note exactly scale, but it's more than a bit similar. If one wanted to scale themselves up into mid-power and then high power, wanted something tried and true, and weren't after variation in design, these would be a good pair of steps. This will probably be my L1 cert bird.

I didn't have the problem with the nose on this one, like I did on the Weasel; I suspected that was a minor one-of glitch.

Since people have said they had problems finishing the nose, I took some time. I sanded with 100 lightly, then 220. Even then, when the primer went on, there were sanding burrs sticking out. No problem, sanding the primer is normal. Second primer coat and sanding with 400, and it was ready for finishing. A single coat of Rustoleum American Accents would have been fine, except for dropping it in the grass while it was wet. One side is perfect, anyway. The other needed sanding and repainting and still came out with detectable flaws. So much for perfecting my LOC nose cone technique.

I used Devcon 5 minute epoxy throughout. The fillets still weren't up to what I'd hoped, and some needed touching up. I need something thinner for fillets. But for building, the Devcon is great.

The shock cord was enourmous -- 7 feet long. Was this a mistake? No matter, I doubled the shock cord into a loop. Double strength, and double safety should one side break. And it's still longer than the chute plus shrouds. Again, I think the chute might be a bit slight, but I think I'll try this one before changing.

The tubes didn't seem to have much spiral when I started, but after finishing they did. I suspect the shrinking of the sealer/primer/finish might be sucking into where the sprials are and making them not only show, but actually sink in some.

No big deal, I've never really cared much about spirals anyway. They're not nearly the drag factor as some other things, like launch lugs. Speaking of which, I didn't use any. This bird, as well as the Mustang I just finished, are dedicated to the tower I just built. And I may have to build it bigger. The Weasel and Mustang may work well with 3 four foot steel rods, but I may have to go to 6 foot rods for this one.

Opening bag to drying paint time: 12 hours. Pics forthcoming.

Next time: Vaughn Brothers' "BoB"
 

DynaSoar

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Vulcanite, finished but not yet detailed.
 

DynaSoar

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For detailing, I wanted something with a big "V" on it. I happened to find it lying on the table. It was the unused self-adhesive decals from the Mustang. Here's the V side.
 

DynaSoar

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And here's the reverse side with a similar but not identical design upside down.
 

DynaSoar

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The Weasel and Vulcanite together for better scale.

A word to those thinking of building the Vulcanite: plan and implement some engine retaining device in the building. Don't wait until after.
 

Rocketman248

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It looks like you're well on your way to quite a fleet.

With regards to the shock cord length, seven feet is actually pretty short. The ejection charge on the midpower motors can be pretty potent. A longer cord allows the pieces to slow down before the cord is completely stretched out. That way you have a reduce chance of zippering or separating.

It looks good though. Keep up the good work!
 

DynaSoar

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Originally posted by Rocketman248
It looks like you're well on your way to quite a fleet.

With regards to the shock cord length, seven feet is actually pretty short. The ejection charge on the midpower motors can be pretty potent. A longer cord allows the pieces to slow down before the cord is completely stretched out. That way you have a reduce chance of zippering or separating.

It looks good though. Keep up the good work!
Thanks for the explanation. Luckily I never hard-connect my shock cords. They all connect with either snap swivel or loop-through the eye. Easily changed or adjusted.
 

DynaSoar

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A follow-up to both the Vulcanite ans the Weasel: they have no positive engine retention, and I didn't know enough to add this into the plans as I was building it. Both got it tonight. I drilled two holes into the epoxy and slightly into the aft centering ring, and epoxied two bolts into the holes. When dry I added washers and nuts. Done. Worked out well enough that I'll probably continue to use this technique, though I won't have to retro-fit them. Drilling into the aft end on an already completed bird was a bit scary. One slip, and it could take lots more work to repair the damage.
 

DynaSoar

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Originally posted by DynaSoar
A follow-up to both the Vulcanite ans the Weasel: they have no positive engine retention, and I didn't know enough to add this into the plans as I was building it. Both got it tonight. I drilled two holes into the epoxy and slightly into the aft centering ring, and epoxied two bolts into the holes. When dry I added washers and nuts. Done. Worked out well enough that I'll probably continue to use this technique, though I won't have to retro-fit them. Drilling into the aft end on an already completed bird was a bit scary. One slip, and it could take lots more work to repair the damage.
Both have now flown successfully.

Here's the Vulcanite after having a repaint with cobalt blue metal fine, whole bird and close-up. The pic doesn't do it justice.
 

xenon

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Very nice looking rocket!
Mine was the same color blue in the nose, and a red body.
My Dad used his for his L1 on an H153, It should go 2900ft or so on that motor, but I'd strongly recomend replacing the shock cord. On his first atempt at L1, the shock cord snapped the payload section back into the body tube on the top. The payload tube was bashed in about half way, he didn't get is L1. The next day, with a kevlar cord and no payload bay, he got his L1
 

DynaSoar

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Originally posted by xenon
Very nice looking rocket!
Mine was the same color blue in the nose, and a red body.
My Dad used his for his L1 on an H153, It should go 2900ft or so on that motor, but I'd strongly recomend replacing the shock cord. On his first atempt at L1, the shock cord snapped the payload section back into the body tube on the top. The payload tube was bashed in about half way, he didn't get is L1. The next day, with a kevlar cord and no payload bay, he got his L1
Mine was a real nice finish of glossy blue at first. Then I added the launch lug. It needed repainting, so I started using what was left from the Mirage. It didn't get near as much clear coat though.

What we need is some kind of resettable or else replaceable shock absorber. Put two loops in the shock cord and put this between the loops with a shorter length than the amount of cord between the loops. Something that'll give and strech, absorbing the pull, but not snap back. Some wraps of teflon tape would work, but it might get expensive. Even if it broke it'd absorb a lot of the shock first.

A spring made out of solder. Yeah, that's the ticket. Rubber screw eyes?
 

DynaSoar

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Wish it luck.

The Vulcanite is presently packed with an Ellis Mountain H50-10. It should apogee about 3300' with ejection .8 seconds after. If all goes well, after the time it takes for a 24" TAC-1 to bring it home, I should have my L1.

Me, I don't believe in luck. I'm a scientist. We have confounds, unforeseen variables and unpredicted interactions. Yeah, right.
 

n3tjm

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Nice Looking Vulcanite :). I had one... loved it. Flew great on a Estes/NCR F62-6.... to bad I lost it in a tree :(.
 

DynaSoar

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Originally posted by rstaff3
Good luck!
Everything else today needed luck, and didn't get it. So I chose not to try. It was just One Of Those Days.

Had an F25 blow its nozzle AND crack the case. Fuel intact in the casing which I got out, delay charhe intact and still in the bird.

It blew the flange off one of my PVC retainers, but everything else was intact (except the motor). Too weird.

Better to way until a day when things go right.
 
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