As you can see I’ve changed the name of my blog to reflect my current passion - model rocketry. I’ve been flying model rockets since I was 12. I was quite ignorant starting out, lighting model rocket motors with a piece of fuse and kitchen matches or even better, a purloined lighter. I would insert the fuse, light it and run like hell but turn around in time to see the launch. This type of “ground support equipment” was of course completely prohibited by all the National Association of Rocketry safety rules and presumably at 12 I was old enough to read those but the fuse was way cheaper than a real launch controller with batteries and so on, and thus more immediately available on an allowance of like a dollar a week. It would have taken weeks to save up for the proper equipment after all lol.
Anyway I flew model rockets until my teens, then again in my 20’s after finishing college and while working as a medical technologist. At age 27 I went to work in Riyadh, Saudi Arabia in 1986. I think model rocket kits were available in Saudi but no motors or launch equipment (of any type lol) were. When I came back home for medical school in 1992 I resumed the hobby & built a few, IMHO respectable scale models: an Estes Saturn 1B, a Mercury Redstone and a Space Shuttle with a little vacuformed shuttle that detached at apogee and spiraled down gently just like it was supposed to. I launched all of them of course and gave no thought to the very real possibility of the sudden sickening loss of a rocket on which I had spent hours and hours and days and weeks on, trying to get a nice finish for once. But that risk is likewise a very real part of rocketry’s appeal to me in an odd sort of way.
In 1999 I finished residency and the rocketry got put away. At that time I had been in the process of stepping up to larger rockets and motors. I bought and started an Estes Master Series Mercury Atlas. It’ll probably never be finished - some centering rings I had already installed are now kind of warped & stuff but we’ll see. I bought an Estes Master Series Jayhawk I’ve opened but never started. I looked last night and the cardboard shroud stock is kind of moldy but I think I can use it. I bought an Aerotech Initiator starter kit with the mid-powered Initiator rocket. This is mostly finished, though I had somehow lost its nose cone over all my moves. However thanks to eRockets.com (thanks Randy!) I was easily able to replace this. But aside from a few D powered flights I never got anything more powerful off the ground.
During all these years I always launched strictly solo, or with my cousins or a few friends. I have never attended any kind of sponsored or NAR sanctioned launch. Then in 2017 I married the woman of my dreams. Bridgid. She’s 100% behind my re-involvement in model rocketry. And now we live in an area with not one but TWO really awesome and extremely active local rocket group - Southwest Ohio Rocketry Association in Lebanon, and the Wright Stuff Rocketeers. They both launch about an hour away. I’ve met several of the members of WSR on their Tuesday night Zoom calls and everyone is extremely nice and helpful. And so far they’ve tolerated all my dumb questions that I’ve asked the group online. They recognize what I learned in medical school, dumb questions are easier to fix than dumb mistakes.
They’re just now resuming launches in our area tomorrow Saturday May 30 2020, following the recent and relative relaxation of COVID-19 Public Health orders. Of course I have to work but I’m definitely planning on making a launch somewhere ASAP. I have 5 birds RTF (all Estes BTW): a Saturn V RTF, a Satellite Interceptor, a D Region Tomahawk, a Mammoth, and a Trajector. I have some motors but only up to a couple of D12-5’s. Thankfully I understand that motor vendors are frequently at launches!
But now to the point of my new blog - documenting the building of model rockets. My first build will be the Semroc RetroRepo kit, the Micron. Originally released by Centuri, it was similar to the Estes Astron Mark II and cost $1.25. I love that because I can actually remember those days lol.
Here’s a photograph of the kit panel (actually, printed on the instructions):
I love the totally retro appearance. The kit is a pretty straightforward build, starting with the motor mount. This kit uses a Kevlar thread tied around the thrust ring. The thread is later attached to the elastic cord part of the recovery apparatus. That’s new to me but I don’t think it’s going to be a major speed bump or anything.
My goal with this build is to try and perfect all the fundamentals of building a model rocket. In particular I plan to experiment with using carpenter’s wood filler (CWF) to fill the body tube seams and the fins. It’ll be my first experience with this technique. BTW, as the build progresses I believe why “Not-So-Good” is part of this blog’s title will become obvious lol.
I saw some videos on the Apogee site describing how to use carpenter’s wood filler to fill fins and body tube spirals. It looks to me like I’m going to have to use two different dilutions of the CWF. For the fins, the stuff the Apogee guy used looked just like mustard to me. Another blog post said to try 2.5 parts CWF to one part water but I don’t think I’ll try to actually measure it, I’ll go with appearance. Another post also suggested whipping the water in until the CWF is like canned cake frosting but I like the mustard analogy better. On the body tube spirals I think I’m going to need thinner CWF. On another Apogee video, a guy used a syringe to apply thinned CWF along a tube spiral in a continuous line. But I think it was thinner than the fin CWF. I don’t have a syringe so I’ll just have to play around with this.
Along with filling these I’m going to try using epoxy putty to fillet the fins. I want to photograph each step of all this to see exactly where and when anything goes wrong. I also want to document the painting process, typically my finishing downfall of late.
So now I’m facing a dilemma. I did remove the fin sheet and did an initial light sanding with 220 grit. Now, I really should thin some CWF and brush it on the fin stock. I would like to follow the example I saw on an Apogee Components Advanced Construction video, which involves at this point removing all the fins and using filler on one fin at a time. The idea is to avoid warping which might ensue were one to paint only one side of the fin stock and wait for it to dry. This actually already happened to me when I built my Satellite Interceptor so I do want to avoid a recurrence. The video suggests inserting a short piece of music wire into the fin’s root edge then using that as a little handle to hold the fin while you paint all but the root edge with thinned CWF. Then you stick the free end of the music wire into, e.g. the edge of some corrugated cardboard to let it dry. I like that. I’ve ordered some music wire but I have no idea if I got the right size. Probably not, but we’ll see, it’s 0.025” so I hope that’s not too thin.
So I want to start the kit right away! But I just checked and saw that my music wire hasn’t yet shipped. So unless I can think of a workaround I suppose I’d best wait for the wire to show up.
I may be back shortly to post a pic of the fin stock I already sanded. But probably not.
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