3" Mac Performance Modified Zodiac

[Banzai88]

...whereas I struggle to find #2-56 or even m2 bolts.

For future reference, most of our rocketry vendors carry them in a variety of quantities. Then there's always the universal supplier, McMaster-Carr. Links provided.

Nylon Machine Screw Shear Pin

2-56 Nylon machine screw, 1/2" length with pan head phillips drive Head diam. .155-.167" / head thick .053-.062"

csrocketry.com

SHEER PINS

2/56 10 PACK OF SHEER PINS

wildmanrocketry.com

Hardware

Hardware & Supplies Quick Link 1/8" - $1.75 Delta Quick Link 1/8" - $2.75 (triangle link) Quick Link 4mm - $1.75 1/4-20 x 2" Eyebolt - $1.50 5mm stainless steel eye nut - $2.75 6mm stainless steel eye nut - $3.50 4mm Eye Swivel (200 lbs.) - $3.00 5mm Eye Swivel (330 lbs.) - $3.75 OUT OF...

macperformancerocketry.com

Small Nylon Shear Pins - 20 pack

Shear pins are used to prevent premature separation of the nose cone from the rocket prior to ejection. These threaded nylon screws are easy to install, and are the standard for high power flyers.

www.apogeerockets.com

McMaster-Carr

McMaster-Carr is the complete source for your plant with over 595,000 products. 98% of products ordered ship from stock and deliver same or next day.

www.mcmaster.com

 

[Banzai88]

Pem Nut McMaster-Carr reference here: https://www.rocketryforum.com/threads/pem-nut-kits-and-shear-pins-kits.165818/page-2#post-2154846

 

[thzero]

McMaster-Carr

McMaster-Carr is the complete source for your plant with over 595,000 products. 98% of products ordered ship from stock and deliver same or next day.

www.mcmaster.com

One has to like McMaster (or Grainger, etc) inventory... but doesn't have to like their insane and after the fact shipping.

 

[thzero]

Well I wanted to see how much volume I really needed for my ejection charge canisters, and well what better way than some math.

Did some searching online for FFFF (using Goex from my stash) trying to find out some volume vs weight, etc. but didn't really find good solid info. So I did some of my own research.

Did some calculations and then printed out a 1" cubic cylinder. Measured before and after with FFFF BP. Then more calcs.

Based on this, and some ejection charge calculators, looks like I start at .75g for drogue and .5g for main. However, based on experience with a similar sized rocket which was 1g and 1g respectively, I'm expecting the testing to end up about there. So I think I'll print out a set of 1 g canisters and then a a set of 1.5 g canisters and use them for testing.

 

[waltr]

So I think I'll print out a set of 1 oz canisters and then a a set of 1.5 oz canisters and use them for testing.

Do you mean 1 & 1.5 gram canisters?
There are about 28gm per oz.

 

[thzero]

Do you mean 1 & 1.5 gram canisters?
There are about 28gm per oz.

Yes, damnit, I did. Updated the post.

 

[thzero]

Ah, so the calculations worked good enough with about a .25" gap for padding, probably a tad much though, but for now to test until I know exactly what grams I want to use they'll work.

 

[thzero]

Nothing exciting here, but another tool that for drilling the shear pins; I ended up going with three #2-56 pins. What I did was use the drill bit for the #2-56 tap into the other tube, then drilled again through the body tube into the coupler. Then the body tube was re-drilled with a slightly larger drill bit just enough to let the pin slide through. Then of course tapped the coupler.

 

[thzero]

Internals for the AvBay with the bulkheads and the ejection canisters installed.



AvBay button'd up with the flags.

 

[thzero]

And nearly fully loaded - in this case I don't have parachutes, the two batteries or 54-38mm adapter.



Weights in at 83.65oz. which is within .5oz of what I expected so should be right about 93.34 fully loaded. Thats right about where I was shooting for. Little slow with the Cessaroni 411 than my standard target of 50 fps, but should be fine on my longer 9' rail.

 

[DerRedMax]

Any progress on this rocket to report?

 

[DerRedMax]

Internals for the AvBay with the bulkheads and the ejection canisters installed.

View attachment 558364

AvBay button'd up with the flags.
View attachment 558365

Where did you get the av bay sled? Looks very interesting for my future build.

 

[thzero]

Any progress on this rocket to report?

Er... no. Haven't bothered painting it, etc... just haven't had time and with weather coming and going around here can't really get the bike and fast car out of garage to be painting!

 

[thzero]

Where did you get the av bay sled? Looks very interesting for my future build.

My own custom design. It's flow in two other rockets

HPR Custom Build

Started a new custom build... thought I'd actually create a bit of a log of it for once. Couple of goals for this rocket Explore some new building techniques Build a rocket that can be launched with I motors in the 2000-3000' range Setup for dual deploy in one of two configurations Dual...

www.rocketryforum.com

Which ended up being my L2 rocket.

And

My L2 Project

Well, am finally starting a L2 project. Even created a set of flash cards (https://www.cram.com/flashcards/nar-level-2-12210980) to study with... think there was another one posted some time ago, but didn't really care for it and the process of creating was good study anyways too. As for the...

www.rocketryforum.com

Which ended up not being my L2 rocket, but did fly the same weekend.

This one was original printed on a Creality CR-6 SE in PETG, but I'm now printing most stuff on a Bambu Labs X-1 Carbon in PETG. I've recently switched to eSun PETG and seem to get better results than the previous Overture PETG with the X-1.