L3 Design Question - Motor Retention

anbhtblr · Apr 4, 2018

Gentle people:

I'm currently working on a design for my L3. I've decided to use Public Missiles' Kwik-Switch motor mounts to allow 98/75/54 mm motor flexibility. I have run across a difficulty, how to do motor retention? My current thought is to use an AeroPack 98 mm retention ring and make adapter rings for the 75/54 mm mounts. Any additional/better ideas?

OverTheTop · Apr 4, 2018

The style you have suggested is my normal and preferred motor mount technique. I usually just turn up some discs that sit on the outside of the case to hold the motor central to the larger tube.

AdAstraPerAspera · Apr 5, 2018

I would drop the quick switch thing and just build 98mm with an Aeropack retainer. Then use their full adapters. The Aeropack adapters can be nested one inside the other to step multiple diameters.

If you put the quick switch in, you will be limited on motor length when using 98mm motors to what fits between the retainer and the quick switch threads.

cjl · Apr 5, 2018

Aeropack's adapters are fantastic, so I'd skip the PML kwik switch and just do a 98mm mount with an aeropack, as AdAstra suggested.

mccordmw · Apr 5, 2018

cjl said:
Aeropack's adapters are fantastic, so I'd skip the PML kwik switch and just do a 98mm mount with an aeropack, as AdAstra suggested.

+1

That's what I did for my L3. I have a 98mm aeropack retainer and a 98-76 aeropack adapter. Worked like a charm.

anbhtblr · Apr 6, 2018

Thanks for the advice. I hadn't considered the length limitation. I'll revisit the Aeropack adapters option.

Regards, Rich
NAR 59673, L2

OverTheTop · Apr 6, 2018

Thanks for the advice. I hadn't considered the length limitation.

I fit the MD retainer at the location that accepts the longest motor I am likely to use (usually 6GXL :wink

. If I use shorter motors I have rods which take up the extra length to the retainer for the shorter motors. I suppose I am biased towards this as I have a lathe and can make my own adaptors.

Buckeye · Apr 7, 2018

I had a Quick-Switch system, and the threads on one of the adapters cracked off (and I am not hard on my gear!). No thanks.

PML has good designs, but they use way too much wimpy plastic for components.

crossfire · Apr 7, 2018

Aeropack is the way to go.

anbhtblr · Apr 9, 2018

Thanks for the advice. I've ordered a 98mm Bluetube MMT and Aeropack retainer and adapter.

Regards, Rich
NAR 59673, L2

L3 Design Question - Motor Retention

Help Support The Rocketry Forum:

anbhtblr

Rich@bna

OverTheTop

Well-Known Member

AdAstraPerAspera

Well-Known Member

cjl

Well-Known Member

mccordmw

Well-Known Member

anbhtblr

Rich@bna

OverTheTop

Well-Known Member

Buckeye

Well-Known Member

crossfire

Well-Known Member

anbhtblr

Rich@bna

Similar threads

Latest posts

L3 Design Question - Motor Retention

Help Support The Rocketry Forum:

Rich@bna

Well-Known Member

Well-Known Member

Well-Known Member

Well-Known Member

Rich@bna

Well-Known Member

Well-Known Member

Well-Known Member

Rich@bna

Similar threads

Join the conversation!

Join today and get all the highlights of this community direct to your inbox. It's FREE!