Semroc Lil' Augie (KA-38)... I got #8... So, where are the first seven?

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K'Tesh

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I just scored Semroc/eRocket's Lil' Augie (KA-38) #8 from Randy (and it's actually INTACT!!! :surprised:)... I think I need to sim this, but it's such a low production number, I hesitate to open the kit... Arrrrggghhh!



I'm curious, who has the other low number Lil' Augies?

Pointy Side Up!
Jim
 

RocketRohde

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I believe Randy keeps all the number 1's and I have acquired number 5.
 

K'Tesh

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Building Tips:

Before removing the binding post from the lower airframe tube/coupler, I'd suggest drawing a line on the body tube and coupler inline with the non-slotted end of the binding post. This will help aligning the parts again later.

When gluing the knot of the parachute's lines, DO NOT use CA glue. CA will wick into the fibers of the lines and harden them. As the lines flex, they will eventually break, causing the parachute to fail, or require replacement. White glue would be best for the knot.
 

neil_w

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K'Tesh, are you actually *building* now? Cool. Is this the first one?

Also, jeffyjeep is nearing the finish line on a build of one of these on YORF. Looks like his is #7.

I still don't understand how the staging is done on this thing. Seems weird.
 

K'Tesh

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K'Tesh, are you actually *building* now? Cool. Is this the first one?

Also, jeffyjeep is nearing the finish line on a build of one of these on YORF. Looks like his is #7.

I still don't understand how the staging is done on this thing. Seems weird.
I've opened the kit, and done a little work on it (mostly simmed it). However, the instructions call for epoxy, and I'm still waiting on that. I talked to Randy and he said that it could be built with white glue. So, we'll see which is better, my patience waiting for it, or white glue.

I was told the staging method is called "Chad Staging". I was told it was named after someone named "Chad" and that the letters aren't some kind of acronym. [EDIT] According to this thread it stands for "Cheap and Dirty Staging".[/EDIT] In this case, the booster's motor recesses into the sustainer's motor tube about 1/3", the sustainer's motor is then trapped by the tube coupler, and a retaining ring. The binding post (the metal part) locks the lower body tube and prevents the motor from blowing through the body tube. There's aluminum tape included to prevent the shroud from being burned by the motors.

Other CHAD staged rockets apparently are done by simply having a motor for the booster taped to the sustainer's motor. The idea is that the booster motor simply falls off at the staging event.
 

neil_w

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Ya, I know about CHAD staging but can't quite figure out the scheme here (even your description leaves me befuddled; I'll need to see some pictures of a finished model to understand it fully). The idea of CHAD staging a kit is odd to me, but it sounds like there is some specific accommodation here, which one day I'll understand. Not that I'm particularly interested in this kit, just the techniques used.
 

kitbasher99

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I helped in the development of this during the upscaleing. How it works is the sustainer motor is loaded where the airframe breaks above the binding post. There is a motor block located near the rear of the airframe to keep the sustainer motor from falling out and the coupler acts as the motor block to keep the motor from going forward. The Booster motor then is friction fit into the rear of the airframe. The Booster motor only goes into the body tube about 1/2".

The first time we flew this rocket it spit the sustainer motor when the ejection charge went off. Luckily it also ejected the parachute, but without the extra weight of the expended motor, I has to chase it quite a ways to recover it.
 

K'Tesh

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The .ork file is up (with Randy's blessing).

Here's a couple of images of it...





The shroud and staging of it was beyond OR's ability to sim the flight characteristics, but you might be able to wrap your head around how it works with this.

Oh, and I have applied some glue to parts, but I'm awaiting the arrival of some epoxy (which is OTW soon) before I really get going on it.
 

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kitbasher99

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My version has 4 fins whereas the production version only has three. I flew it on Saturday on a F 15/ E 16-6 motor combination. I had a Jolly Logic Altimeter 2 aboard and it flew to 1455 feet and flew flawlessly.
 

BEC

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I got one a few days ago....no production number on mine.

I've seen Big Berthas flown CHAD staged. The Bertha has so much stability margin the extra weight hanging off the back is no issue.
 

BABAR

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I have cloned this, it is a great design.
 
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