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Showing posts from April, 2020

Plastic Chutes

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The Thrifty Rocketeer blog continues...

I was just chatting with a fellow rocketeer about FlisKits and the need to cut your own balsa (not a big deal) and assemble your own plastic chute.   And that's when it hit me:  Here's a topic for this week's blog entry!  What follows is a quote or two from our discussion on Facebook.

A couple of years ago, I realized that if I melted a plastic chute while out on the launch range, I'd be screwed. So I saw Jon Rockets.com had a 10 or 12 pack of 3 mil plastic parachutes for a very reasonable bulk price. So I got on line and ordered a bundle.

When they arrived, I pre-made them into 12"-15"-18" chutes and labeled them, folding them into small snack-sized zip-lock baggies.

I think I've still got one or two, having melted or ripped a chute over the years!

I found this to be A good, cheap investment!




Now, I know some rocketeers who swear by nylon chutes, and want to buy the best for their sport rocket. And there…

The Maple Seed: How NOT to score motors

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So now that I have finished my build for the Semroc Maple Seed rocket, I'm ready to fly, but noticed I don't have any C11-7 motors to launch with. I started a search on-line, and found Hobby Lobby doesn't stock them, and couldn't turn up a local store with them. So I searched on eBay and found ONE Canadian seller who had a 3-pack for $12.95 and $5 shipping. So I did a little math and decided that was near $4 a motor, still cheaper than paying hazmat charges, so I pulled the trigger. Almost simultaneous, a fellow rocketeer was kind enough to offer to pick up a pack from eRockets, and told me he had them. So, knowing that I'd launch the rocket multiple times, I agreed to pick them up from him. His pack is a 2-pack of the same C11-7 value motors and runs about $8... so they're right in line with what I'm expecting. We met for coffee at a drive thru and he gave them to me. Now the Canadian package arrives, and I notice that i…

Blast shields

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Last entry, I mused about assembling a simple set of launch pad gear, complete with a launch rod, launch pad wires, and alligator clips to attach to a battery.

I also lamented not having settled on a good, simple blast shield for my launch rods yet.  I asked for some suggestions.

Well, an experienced rocketeer responded with a simple suggestion.  And  I immediately took to it...I think.   What he suggested was a Terra Cota plant pot.   

I think I have heard of this before, as a poor man's way to set up a simple launch pad that won't burn.  When up-ended, the pot would act as an anchor and a blast shield.  The launch rod can be slipped down through the large hole and into the earth.  At least, that's what I envisioned.

But I've already built a couple PVC launch pads, and bought a few launch rods in preparation.  Since I've already got the pads set, I just need the shield.  And that's why I did it.

I went to Lowe's and looked…

Low Power Launch Pads

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A couple of months ago, I posted a picture of a power cord that had been modified with alligator clips to be part of a launch cord lead.

It was my attempt to start assembling my own set of launch gear, in the event that it would ever be needed.

Little did we know at the time that a choronavirus pandemic was coming, and that many rocketeers would be self-isolating, and building up their fleets.   Or that all NAR club meetings, assemblies and launches would be cancelled.

But here we are.

Now, most low power guys (whether they started as boys, or joined the hobby as men) have acquired at least one Estes launch pad and controller, sort of as a rite of passage.  The small controller box, with a key, indicator light and launch button, holds something like 3 or four AA batteries to get up to 6 volts an at least 15 feet of twisted pair wires that run out to small alligator clips.

I can't tell you how many of these I have run into, having found them at sec…

The Maple Seed - Part 2: The balanced seed fins

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We continue our build thread for the Maple Seed by Semroc, marketed by eRockets.biz We've already covered the motor mount, body tube and the nosecone last installment.
Houston, we have a problem.  Most all the photos from the critical build of the seeds are gone. My computer crashed. However, I can describe a lot of the steps through the existing photos and point out the critical error I made when it comes up.
The Instructions are clear with photos to help orient your seed wing/fin in a particular direction. Unfortunately, I can't orient my above photo right now, as my operating system has changed and flipped several photos top for bottom. (But I'll try to correct that.)
You start with one of the large pre-cut sheets in the shape of the seed wing. (I'm going to use the terms seed, fin and wing pretty interchangeably here.)
You'll note that the head of the seed is to the right, and the sail of the rest of the fin is to the left. It's h…

The Maple Seed - Part 1: Motor mount & body tube

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After several months of coming down on the wrong side of the fence, I spotted a sale on the novelty rocket "The Maple Seed" made by Semroc and distributed by eRockets.biz

I recognized that someone had put a lot of design time into this rocket which sheds its fins, only to have them spin and tumble down to earth.  That's the appeal.  Plus, the rocket main body recovery under a parachute.
Now, you may think that this would not be a difficult challenge to design and produce. However, the more you think about it, the more you will realize you have at least four separate "parts" to produce for recovery.  Plus, if it was all that easy, why hasn't someone done this before?

This last month, I spotted the sale price, and being a bit bored at home, I figured I could have a friend pick one up for me and when I saw him, I'd pay him the $30 for the kit.  As it turned out, I got it both sooner and later than I had expected.

So on a …