Hardline
Ecstatic and Joyous
Wayne said I had to write my own build threads now so here it goes and hopefully I won't embarrass myself......:smile:
When Wildman had the Jart sale in August I Just Had To Get One....but it took until now (November) for me to actually get to building it. I was reviewing the Wildman site in preparation for the Black Saturday Sale and noticed the Wild Child "Fly and Foam" technique that he had posted and decided that I would build the Jart using that method.
So I pulled out my build box (which Wayne has learned To Never Touch....):
I had already washed all the parts and scrubbed off the "stuff" (that is a technical term for sticky bits and pieces of fiber on the fins - I am sure it has a name but to me it is "stuff") and had reviewed all the build threads on this forum (thanks Chadrog for your "Family Drag Race Build Thread!) and downloaded the RockSim File that someone (I forget who - sorry) had posted and opened it up in Open Rocket. I determined that I wanted to make it in to a "Night Jart" and my build was planned accordingly. I also prefer to have Aero Pack Motor Retainers which does simplify certain aspects of the build (the downside of course being the additional cost but hey, you only live once so go for it)
The first order of business was to work on the motor mount. I filed a small notch on the inside of the top centering ring to allow the kevlar cord to fit. Then I sanded the exterior of the motor mount tube, slid the centering ring over the kevlar cord, tacked it into place with thin CA and used the thin CA to glue the top centering ring 1/4' from the top of the motor mount tube. Then, after it fell off, I redid the whole process using medium CA which worked a whole heck of alot better (Lesson learned: use the correct adhesive for the task)
Note the two tape tabs to pull the rear centering ring off prior to foaming.
Next I slid the motor mount into the rear of the tube, aligned so that the centering rings were at the front and rear of the fin slots and tacked the fins with just a few drops of medium CA (application of lesson learned), making sure to align the fins properly:
Then I pulled the tabs and removed the rear centering ring and placed the jart in a leftover flower vase (Wayne likes to give me flowers and the vases come in handy!)
I made sure to cover the motor mount tube with tape to keep foam out.
I used 30ml part A (with 4 added drops of water) and 30 ml part B of Public Missiles Adjustable Density Expanding Foam:
Trimmed up the foam and and epoxied in the rear centering ring since I like the "finished look" although structurally I don't think it needed to be installed. Then I went ahead and installed the Aero Pack Retainer with JB weld:
After letting it cure for a day I started work on the nose cone
After analyzing open rocket I decided on 3 oz of BB's, epoxied in place, and foam to secure the "glow stick/flashlight" I found of $4.99 at Walmart:
Getting ready to foam:
I used 5ml part A with one drop of water and 5 ml part B to foam in the nose cone to keep the BB/epoxy mass from moving but the keep enough room for there to be enough glow to keep it a "night jart". I ended up with 4.97 inches of stability according to open rocket.
There is a SSS launch this upcoming weekend and I'll post up how well the Jart does on it's first launch. I ran it through Thrust Curve and determined it's first flight will be on a Road Runner Single Use G80-7.
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