LOC Precision 4" Iris

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I used a piece of maple for the rear rail guide with the nut recessed and epoxied into the back of it. The forward rail guide is screwed into the FCR. I'm not sure how far apart these rail guides need to be, but for a 80" rocket they look too close together. Right now they are 15-1/2" apart.

It'll be fine.
My old (now retired) PML Endeavour had 14" between the buttons on ~70" length. Always flew great.
 
I guess that I should dig out my old Yank 4" IRIS then... Since all the pictures of it in the Yank gallery disappeared with the changeover.
It was a good flier. Handled any K that I could put in it. I didn't glass it, just foamed the fin can.

Yank IRIS instructions . . . PDF's below.

Dave F.
 

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Well, almost 2 years have went by. Going to finally get the Iris finished up and get my level 1 cert soon.

I'm looking for recommendations on what motor to use. I would like to keep the altitude under 2,000ft. I want to use a motor ejection charge, and I'll probably use a chute release system at lower altitude.

Do you recommend using shear pins?

Thanks in advance.
 
Well, almost 2 years have went by. Going to finally get the Iris finished up and get my level 1 cert soon.

I'm looking for recommendations on what motor to use. I would like to keep the altitude under 2,000ft. I want to use a motor ejection charge, and I'll probably use a chute release system at lower altitude.

Do you recommend using shear pins?

Thanks in advance.
If you're putting out the main chute at apogee with motor eject, then using the CR to reef it, you don't generally need shear pins on the NC. Just ensure the NC is a snug fit.

Shear pins are commonly used for 'full' dual deploy set ups (ie where electronics in the av bay fire the sep charges in two stages). In such cases, the force of the apogee charge that is intended to separate the booster/fin can assembly from the payload/nc assembly can inadvertently shunt the NC off if the NC is just friction fitted, thereby prematurely releasing the main at apogee (ask me how I know this). So in that case, shear pins are used to retain the NC until the rocket has descended to pre-set main release altitude. Conversely, with a CR set up, the NC is supposed to come off at apogee.
 
Here is my Mega Magg with the combo Dave is talking about. This is how the motor retention is used on the 4” IRIS. No need to buy anything unless you want to simply change how it looks. This example used the retention on a Aerotech 75mm casing. The other side shows how the “T-Nut” peeks through the hole and where the screw mounts the “Z-Clip”. I also have a 4” IRIS I need to complete. Of course to note the 4” IRIS is 54mm with the ability to adapt down to 38mm and 29mm. Let me know if you need any questions answered on any LOC builds. #theLOCmafia
I am building the LOC 4" Goblin using the included motor retention and adapters. However the 38mm adapter screw holes for the clips causes the screws to press against and indent the aft centering ring. Maybe shorter screws is the solution?
 
I am building the LOC 4" Goblin using the included motor retention and adapters. However the 38mm adapter screw holes for the clips causes the screws to press against and indent the aft centering ring. Maybe shorter screws is the solution?
I also built the 4" Goblin. I added a plywood spacer to fill the gap caused by the 'T' nuts. Then good size epoxy fillets. The joint between the MMT and the rear ply disk takes the entire motor thrust.
 
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