What did you do rocket wise today?

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jqavins

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I finally got sick of that and created new .eng files under the brand "Estes_w_adapter" for the C11, D12, and E12 with the mass and length of the adapters morphed in, imported them to OpenRocket, and was back in business.
Keep up that sort of thing and you'll have to change your user name.
This particular rocket has some peculiar design constraints: it needs to sit stably on its fins on display
The clipped tips of the fins on Big Bertha are good for that.
 

bad_idea

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The clipped tips of the fins on Big Bertha are good for that.
Yes, what I have so far are essentially that style of fin, though a bit wider in span and a bit shorter of leg, with the hard angles broken by transition angles.

Unfortunately I can't get it to sim well on both a C and a G without messing with removable nose weights I don't really want to bother with (either in flight or - especially - in repeated simulations). I know tube fins would nail the stability without costing much weight, but they're a real drag on altitude with the bigger motors. D is acceptable as the minimum motor, but I had hoped it would fly well on any Estes, Quest, or HobbyLine 24 or 29mm. I need to work on weight at the rear of the rocket.

But in the end, working on future designs is basically a way to procrastinate from doing sanding and filling on work in progress.
 

jqavins

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C11 seems like a small sacrifice if exchangeable nose weights are something you want to avoid.
 

bad_idea

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C11 seems like a small sacrifice if exchangeable nose weights are something you want to avoid.
Agreed, especially since most of the municipal restrictions I see are "D or under," and frankly the C11 isn't all that inspiring a motor anyway. The design is for a friend who is dipping his toe back in to rocketry but with perhaps less interest in minutia than I, so the loss of the C won't matter much given every Hobby Lobby has the D and E, and nearly every park can fly a 56mm D with good odds of recovery.
 

teepot

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I thought I would build a 29mm and 38mm minimum diameter rockets. I started on the 29mm one tonight. The execution is harder than I thought when I was building them in my head. It's like trying to put 10lbs in a 5lb bag. It needs to have an Av Bay. I am going to use a thick walled 24mm motor tube as a coupler. It's a perfect fit in the 29mm heavy walled motor tube I'm using for the body. I would like to find something to hold the Av Bay together besides a 1/4" threaded rod. I'm putting a MW RRC3 with a screw switch and a LiPo battery in it. A 29mm hole saw makes good end caps. I'll plug the hole with epoxy and drill a new hole below the center for the rod. Anybody know of a different way to hold the Av Bay together? I'm all ears or eyes as the case may be.
 

rharshberger

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I thought I would build a 29mm and 38mm minimum diameter rockets. I started on the 29mm one tonight. The execution is harder than I thought when I was building them in my head. It's like trying to put 10lbs in a 5lb bag. It needs to have an Av Bay. I am going to use a thick walled 24mm motor tube as a coupler. It's a perfect fit in the 29mm heavy walled motor tube I'm using for the body. I would like to find something to hold the Av Bay together besides a 1/4" threaded rod. I'm putting a MW RRC3 with a screw switch and a LiPo battery in it. A 29mm hole saw makes good end caps. I'll plug the hole with epoxy and drill a new hole below the center for the rod. Anybody know of a different way to hold the Av Bay together? I'm all ears or eyes as the case may be.
#6-32 all-thread works and is stronger than needed in a 29mm MD rocket. I have heard bicycle spokes will work nicely as well.
 

OverTheTop

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#6-32 all-thread works and is stronger than needed in a 29mm MD rocket. I have heard bicycle spokes will work nicely as well.
I have used titanium spokes on 54mm Avionics bays and other situations. They don't take up much space and have a breaking limit of about 280kg. You get them made to length at bike shops that have the thread-rolling facilities. They also make really good long bolts when needed.
 

jqavins

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Anybody know of a different way to hold the Av Bay together? I'm all ears or eyes as the case may be.
My mind is aglow with whirling, transient nodes of thought careening thru a cosmic vapor of invention. But everything I think of is totally impractical.
 

boatgeek

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My mind is aglow with whirling, transient nodes of thought careening thru a cosmic vapor of invention. But everything I think of is totally impractical.
An AV bay for the insane gambler!
 

hobie1dog

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I received the new drill chuck that I found on eBay and mounted it on the adapter on top of the new K & F tripod that I recently got, so we just have to go to the dollar store and buy a pan top so that will have a brand new blast deflector and then we can have the rockets at waist level and be able to tilt the head over easily and mount the Rockets on it, changing from 1/8 in launch Rod to a quarter inch Rod will be easy now.
 

Cape Byron

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DigBaddy

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Day off from work (gotta burn 'em or lose 'em) so I got the woodstove fired up in the shop early and got the MDRM, 29mm Bigger Daddy and 2.5" Nike-X covered in sandable primer. Should be able to sand (yipee) later. May run to a hobby shop today to find some stuff for a dumb build idea I have and probably buy too much other stuff.
 

Mach_Seven

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I created a six page checklist for my Firestick XL.
View attachment 491936View attachment 491937View attachment 491938
Day off from work (gotta burn 'em or lose 'em) so I got the woodstove fired up in the shop early and got the MDRM, 29mm Bigger Daddy and 2.5" Nike-X covered in sandable primer. Should be able to sand (yipee) later. May run to a hobby shop today to find some stuff for a dumb build idea I have and probably buy too much other stuff.
Can i come?
 
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Just tested the main ejection charge for a 2" diameter scratch build. I'm working my way towards dual deploy and after building the AV bay figured this was the next step. Used .3 grams BP, 2 #2-56 shear pins and and ejected the NC about 15ft. This seems about right to me but if anyone has thoughts I'd be happy to hear. I did not have the shock cord and parachute inserted, would this affect the amount of BP?
 

jd2cylman

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Just tested the main ejection charge for a 2" diameter scratch build. I'm working my way towards dual deploy and after building the AV bay figured this was the next step. Used .3 grams BP, 2 #2-56 shear pins and and ejected the NC about 15ft. This seems about right to me but if anyone has thoughts I'd be happy to hear. I did not have the shock cord and parachute inserted, would this affect the amount of BP?
Always test in flight configuration. So, shock cord and nomex covered parachute should be installed before testing.
 
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