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Timing the Thrifty Rocketeer

You may have noticed that the Thrifty Rocketeer blog is now coming out once a week.  This isn't by accident.  Well, maybe it is...but bear with me here...

When I started this blog, it was in response to a challenge by The Rocket N00b, who was trying to encourage everyone to start a blog and flood the internet back in November with Rocketry bogs.

I guess I misunderstood him, as I wasn't clear if he was asking for a daily blog, or something more periodic.

So, after a bit of time (like almost the whole month slipping by)  I decided to launch in with a build thread around Thanksgiving.  I had time on my hands and I thought that I might give it a whirl.

My writing ability and touch typing got the better of me, and it was easier to start than I thought.

I also was under the impression that people would be eager for each new installment of the blog build thread.  But I was wrong on a couple of points.

First, you don't want to flood your readers with updates too often.  Not everyone rea…

Super Big Bertha-- Part 5: Paint job

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It's almost time for the final step in this build thread.  After gluing and finishing the construction, I've stopped just short of gluing the coupler and attaching the two halves of the body tubes together.  The reason for this is that I'm going to attempt to install two rail buttons after construction is completed, but as long as the coupler isn't in place, I can still reach down the throat of the body tube and install one correctly. The other will be uncomfortably close to the "tail pipe" but should be clear of it.

So, the first step in finishing was to select a primer paint and spray the entire body tube, fins and nosecone.  In my case, I had a few passes of Gloss White Rustoleum left in one can, and an entire can of "Primer plus Paint" flat white Krylon.  So, after choosing carefully, I hit the sealed wooden fins with the Rustoleum once, and then moved onto the body tubes.  I shot the body tubes with the flat w…

Balsa fin excess

The Thrifty Rocketeer continues...

OK, here's where this blog earns its name... "The Thrifty Rocketeer"!

For several years, I have been puzzling over an aspect of model rocket kits that confounded me.  That is, it has been a question that pops up at least once during each build session, but then gets swept aside until either clean up, or gluing inside a body tube.  You'll see what I mean...

In today's modern technology, we have eliminated the need for templates and patterns to be traced and cut out of fin stock.  Instead, we advanced first to the die-press plates that stamped or "cut out" the fins so that all the new rocketeer had to do was simply slice the few remaining bridges or tabs to complete the outline of the fin.  Presto!  With a little sanding, you had a perfectly shaped fin, with the wood grain correctly oriented for strength.

The next phase was the introduction of laser cutting of fins, again with minimal balsa wood bridges or tabs left to be sl…

Super Big Bertha -- Part 3: Another motor mount!

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The first step in this construction is supposed to be the motor mount.  And often I will plunge in and do that right away, so that it can be drying while I work on another part.

But this time, I waited until after I had done the fin assembly.

I carefully sliced out the three centering rings and assembled the various parts for this motor mount.    Much later, a screw on motor retention device will be added, but after the rocket is pretty much assembled.

Now, the instructions indicate that you are to measure 1/2" from the tail end of the motor mount tube for the last centering ring.  The middle ring is 3 inches from this end, and the top ring is 7 1/2" from that same end.  (This also can be seen as 1/2" from the top end, but who's counting here.)

You can assemble and glue all three in position without much trouble at all, and I did this.  Then I realized that I had rushed into it without thinking it all the way through:  When assembling t…

Super Big Bertha-- Part 4: Odds and ends

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While my fins dry, I thought I might address a few other items that can be prepared in preparation for the next step.

First, the kit came with two body tubes. We've been working on the bottom body tube, while the top half has been waiting patiently until now.

If you've not already done so, try fitting both the nose cone in one end, and the coupler in the other.  I personally prefer to orient my body tubes so that if not perfectly round, the coupler or the body tube will stiffen and reform that roundness.

I also chose to insert half the coupler into the top body tube with a layer of wood glue smoothed on the inside of the body tube, instead of applied to the coupler. The difference is where the squeegeed glue winds up. Instead of being piled up on the coupler, it is shoved further into the tube. It doesn't hurt if it dries there. But if it's on the coupler, it could leave a ridge or form a separation between the two body tubes.

When prepari…

Super Big Bertha -- Part 2: The fins

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Well, I couldn't resist, so I started the build of the Super Big Bertha that Santa left me on my front porch.

One of the things I love about kits like this are the Through-the-Wall construction, as well as the sandwich fins.  The first time I encountered this was in my Mega Mosquito kit, and I loved it and learned a couple of things. Apparently, not well enough too...

The first step after slicing open the package with the instructions in it, was photocopying the second page so that i wouldn't have to slice up my instructions.  But the next step was to lay-out the balsa.  I discovered two different sets of balsa:  One set of four fins was about 1/8" thick, and one set of 8 fins was 3/16" thick and a solid sheet.  That is, these were the exterior fin sheets.  The thicker sheet had cut outs in the shape of triangles, that I removed and saved. (You never know when you're going to need this spare, scrap balsa.) In fact, I saved all the …

The New Year's Eve Parachute

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An amusing follow up to my earlier blog entry about umbrella parachutes.

Just yesterday, as I was driving into work, I passed something on the roadway as I hit the entrance ramp to the expressway.

This is the same location where I stumbled across a crushed Alpha II rocket several months ago. (It was pretty trashed, but someone had written "Have a Nice Day" on the nosecone. But that's another story.)

I'm not sure why I noticed the aqua-blue material along the roadway, but something registered in the back of my mind.   I made a mental note and hoped it would be there on the way back, cause I was already up to 40 mph and accelerating in traffic up to the highway.

Sure enough, coming back after midnight, I took the exit ramp, turned onto the shoulder and slowly inched toward the entrance point.  There it was.

I turned on the flashers and trotted along the berm of the deserted roadway to where it was pinned in my headlights.  I picked it up a…