7.5" Honest John Build

UPscaler

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Howdy ya'll!

Not too long ago, I purchased a classic Smokin Rockets 7.5" Honest John kit here on TRF. Instead of the single 98mm, I opted for a central 75 with four outboard 38s. @tjsnakez made me some centering rings with plywood left over from our big Punisher build, and I set to work.

Here are some photos spanning from test fitting to fincan assembly. I built the rocket with the ability to slide the fin can out the rear and fillet all the internal stuff, then glue it back in.
After gluing it all in, I boldly decided to do all 8 fillets at once, which is a bit crazy on a rocket this size...but it went okay!

If you want a detailed look at the construction, here's my video on the build:



Still some fit and finish to be performed, but the rocket is about 95% done.

Things left to do that I'll be covering here:
Recovery system, electronics bay, finish sanding/smoothing of the fillets.

The first flight is planned for the spring sometime on a central M650 with two J570s and two J350s all lit on the ground!

Braden
 

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Sandy H.

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Cool rocket and nice build. I'm curious as to why you chose 2x J570 and 2x J350 for the outboards. They both are W propellant, so the main difference seems to be burn time (and burn profile, obviously). Not second guessing your choice, just curious why you decided to go that route. I've not flown complex HPR, but enjoy watching others do neat flights like this for sure.

Hope to see the video of the successful flight in the spring!

Sandy.
 

UPscaler

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Cool rocket and nice build. I'm curious as to why you chose 2x J570 and 2x J350 for the outboards. They both are W propellant, so the main difference seems to be burn time (and burn profile, obviously). Not second guessing your choice, just curious why you decided to go that route. I've not flown complex HPR, but enjoy watching others do neat flights like this for sure.

Hope to see the video of the successful flight in the spring!

Sandy.
J570s hit super hard and I don't have the hardware to support flying four of them. ;)

White Lightning makes INSANE flames when clustered, so putting a bunch of it together is going to be awesome.

Braden
 

UPscaler

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Alrighty folks, if you're familiar with my history, you'll know I'm not a fan of hiding mistakes. So I won't!

I got a little lazy on the fillet smoothing before spraying because I wanted the rocket to be painted at the end of the video. However, I entirely forgot to sand one of the fillets down, and it was an especially lumpy one from getting a little heavy-handed with the colloidal silica. No problem! We've just got to do some hefty sanding. A good workout, if nothing else.

Up next is sanding down the filler, then palm sand the tubes and throw some more paint over top!

Braden
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