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Old 07-21-2011, 01:35 PM
Carl@Semroc's Avatar
Carl@Semroc Carl@Semroc is offline
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Location: Knightdale, NC
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Originally Posted by Chas Russell
Having worked Standards and Testing way back when, I think you would have to get their input about what they would certify both from a safety and a contest certification point of view. I have WAY too many 18mm composite reloads as once a pak is impounded and then opened, it cannot be used for competition again (must be an unopened pak). This is so the modeler does not "modify" components. This could be carried oper to a multipak of delays.

Seeing as some of the S&T members will be at NARAM for the Board of Trustee meeting, you might want to take them into your confidence and see if they have issues or suggestions.
We didn't call it Standards and Torture fur nuthin'!

BoT 9 years, S&T 3 years, first MESS chair, NARTREK 3 years or so, Contest Board very briefly before overseas assignment...
and the beatings go on.


Your points are well taken. DECAPS have been tried by at least one other company since we had then in the 60's. Our first attempt did not work well. It depended on the skills of the user. The second with 13mm inside 18mm did work better. We will have larger ID's in our 18mm and our DECAP will not fit in Estes or Quest engines so we don't have that problem. The top will be flared sligtly so it will be dificult to insert the wrong way. But, all that said, if it is not safe to use, we will not do it.

This group has more combined expertise than could have even been imagined 50 years ago. Thanks to all for your input and suggestions.
Carl McLawhorn
NAR#4717 L2
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Old 07-24-2011, 02:00 PM
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PaulK PaulK is offline
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Originally Posted by Carl@Semroc
1. Would it be worth the extra $.25 to have the ability to select delays?
2. Would the average (over 18) user be able to "figure it out"?

1. Yes! Not only the flexibility of selecting any delay for any motor, but this means that all motors are available as boosters!
2. Depends on definition of average user, but with good instructions, yes.

I remember you telling me about this years ago at iHobby, I'm glad the idea is still a possibility!
If we weren't all crazy, we would go insane - Jimmy Buffett
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Old 07-28-2011, 05:55 AM
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kurth kurth is offline
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2) If you can assemble an aerotech reload this should be easy.

every motor available as a booster? and separate delays? Brilliant!
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Old 07-28-2011, 06:23 AM
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mrhemi1971 mrhemi1971 is offline
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Thats the way a motor should be offered, being able to have the choice of whether i want a motor to be a booster or delayed is fantastic! Do SAM's get testing duties?

You are only limited by your imagination......

Ryan Leach
NAR# 87642
SAM #216
SoJARS NAR Section 593
Aerospace Education Officer
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Old 07-28-2011, 07:20 AM
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Solomoriah Solomoriah is offline
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I recall suggesting something like this some years back myself. It's a great idea (but then, I would think that, wouldn't I?)
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Old 07-29-2011, 07:48 AM
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STRMan STRMan is offline
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I think this DECAP idea is brilliant, provided I can vary the delay of Semroc B14-0's at will.

(Did you see how I slipped that in there? )
"AND I hope they are from the planet of the "Chunk spunky Mary-Lou Retton clones". - Ironnerd

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"Semroc is almost always the answer" - Stefanj
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Old 07-29-2011, 08:14 AM
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Ltvscout Ltvscout is online now
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Originally Posted by STRMan
I think this DECAP idea is brilliant, provided I can vary the delay of Semroc B14-0's at will.

(Did you see how I slipped that in there? )

Ya, to fit into my Semroc Payloader II with true ST-10 size tubing.
Scott D. Hansen
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Old 07-29-2011, 09:09 AM
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ghrocketman ghrocketman is offline
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I want to sign up to beta-test these.
When in doubt, WHACK the GAS and DITCH the brake !!!

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, if you have to ask what is "NORMAL" , you probably aren't
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Old 07-29-2011, 09:27 AM
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Doug Sams Doug Sams is offline
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Location: Plano, TX resident since 1998.
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Originally Posted by Ltvscout
Ya, to fit into my Semroc Payloader II with true ST-10 size tubing.

My wife asked, "Does this tube look about the right size?" I replied, "Yeah. ST-10. BT-50. Close enough." And then the fight was on


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Old 07-29-2011, 10:17 AM
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jharding58 jharding58 is offline
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The points and solutions raised are valid and informative. The only concern I have is market size versus production run overhead - basically I do not want to see Semroc burdened with sunk cost in a product that is slow to move a la SLS. Is your assembly process for the "packaged motors" also using the DECAP module or are these produced in a standard manner? In the packaging process is there a temporary cap on the propellant that requires removal prior to the insertion of the DECAP? Color band on the flared end of the DECAP to provide a sight cue for insertion?

The virtually infinite variety of combinations of motor burn and delay would be a welcome option for a select group. I just do not have a feel for the mass market appeal, and the added preparation step for the average modeler. At your price point you are comparable with Estes MSRP for packaged, and I have no doubt that retailers will be able to discount. Even at plus 25 cents per I doubt that there would be a real pricing concern. The issue of selectable delay charge is I think fairly sophisticated choice and while the assembly of the DECAP might be a doddle, the combination of model weight and motor thrust might be more math than Joe Average could exert and result in a lot of Tau Zeros blowing their NC into the ground after a really pretty ballistic fligth.

Conceptually I am right with you. The ability to provide a bespoke delay on a model is an absolute selling point for a sophisticated user (which everyone here is). As for the assembly I even envisaged a light ply reload press to seat the displacement fit DECAP into the Semroc motor, but then I over think everything...
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"The complexity of living is eminently favored to the simplicity of not."
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