Motor retention for madcow 4"squat

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redleder

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Any recommendation for a motor retention system for the 54mm motor tube? I want to buy one and dry fit first before I start epoxying the motor tube and rings in place. The tail end tolerance looks slim and do not want to have a bunch of tube sticking out if I can avoid it.

Thanks,

Jarod


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chris m

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I'm using a t nut and all thread on one
 
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o1d_dude

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There's nothing wrong with an Aeropack motor retainer...well, other than the cost.

Mine uses Kaplow clips.

If the kit hasn't been changed since I built mine many years ago, understand that you will have cut off the base of the nose cone to provide room for the chute and recovery train. Also nose weight will almost certainly be required. BTW, getting paint to adhere to Madcow nose cones can be a challenge so many rocketeers don't bother painting them.

My Squat likes to swim and can locate a puddle, creek, or pond wherever I launch it.
 

Flyfalcons

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You could just glue the motor mount tube flush with the aft centering ring and use a flanged retainer if you're concerned with how much tube can stick out the back.
 

Steve Shannon

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I have used mirror clips from Lowes before with the aft end of the motor mount tube flush with the aft centering ring.



Steve Shannon
 

redleder

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Cool. I like the super simple options. Makes sense. I guess the 54mm motors have some sort of flange to keep the rocket from blowing up through the tube right?


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soopirV

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Cool. I like the super simple options. Makes sense. I guess the 54mm motors have some sort of flange to keep the rocket from blowing up through the tube right?


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Yup- the aft closure of the cases I've used (CTI and AT) are the thrust-ring as well. Have not flown other motors, so YMMV with things like Ex casings and DMS
 

AfterBurners

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I like the AP flared retainer. Has a really clean look.
 

MikeyDSlagle

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I like the aft ends of my rockets to be flush and clean. I don't like the looks of a big threaded retainer on the back, there are some exceptions of course. I like the clips Steve posted but they are not available locally. And theyou don't work very well for snap ring cases like Loki. Loki says not to put the clips on the casing itself but rather go to the snap ring. If you use the clips, cut the rounded part off one end and use it backwards/upside down or whatever; and you'll need holes closer to the motor. I've gotten to where I use aluminum rings instead.

Oh, I wouldn't consider a rocket with a 54mm hole to be MPR. :D

Mikey D
 
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cavecentral

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With short motor tubes and retainer systems , watch for adapters. Ones like aeropack's are too long and the centering ring is beyond the end of the motor mount.
 

crossfire

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The new style Aeropack retainers are much shorter than the old style.
 

redleder

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I like the aft ends of my rockets to be flush and clean. I don't like the looks of a big threaded retainer on the back, there are some exceptions of course. I like the clips Steve posted but they are not available locally. And the work very well for snap ring cases like Loki. Loki says not to put the clips on the casing itself but rather go to the snap ring. If you use the clips, cut the rounded part off one end and use it backwards/upside down or whatever; and you'll need holes closer to the motor. I've gotten to where I use aluminum rings instead.

Oh, I wouldn't consider a rocket with a 54mm hole to be MPR. :D

Mikey D
I know, I was on the fence between MPR/HPR. With the smallest 54mm motor I could find it was in the MPR impulse range. I will probably try to get my L1 with this one this fall.


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Steve Shannon

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I know, I was on the fence between MPR/HPR. With the smallest 54mm motor I could find it was in the MPR impulse range. I will probably try to get my L1 with this one this fall.


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What do you consider MPR?
The single grain 54 motors are all I impulse range. They're HPR.
https://www.apogeerockets.com/Rocke...Grain-Motors?zenid=ri7n8pfbgb844cecn16i4s1td2
https://www.aerotech-rocketry.com/c...MS_Instructions/54mm/54_426wtfjr_in_20079.pdf



Steve Shannon
 

blackjack2564

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WARNING:

Be sure to add nose weight to your Squat.
This model MUST have nose weight to fly correctly!!
No if's-and's-or but's! Mentioned several times in the instructions. Every one I have seen fly [attempted flight] without any weight ended very badly [at least 6-7]
Don't get why, some guys don't follow instructions or advice.

Use lightest retention possible. You don't want more weight on the rear.
Screw and washer or mirror clip is way to go.
 
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redleder

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Hi Steve, you are right and I was wrong. I got my wires crossed in my mind. I have a 38mm rocket that I am working on as well as for some reason was thinking about that one when I was crossing referencing motor types before posting. I will be using an I motor more than likely for my L1 on this one. I still have a lot to learn.

Thanks,

Jarod


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Steve Shannon

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Hi Steve, you are right and I was wrong. I got my wires crossed in my mind. I have a 38mm rocket that I am working on as well as for some reason was thinking about that one when I was crossing referencing motor types before posting. I will be using an I motor more than likely for my L1 on this one. I still have a lot to learn.

Thanks,

Jarod


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That's what I like best about this hobby. No matter what, there's always a lot left to learn.
Have fun learning!
 

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