3D printed retention?

[Sparrowhawk]

I'm designing a rocket with a 41.6mm (BT-60) body tube and a 29mm motor mount; I couldn't find any (cheap!) engine retention solutions for composite engines at these dimensions, as all the (cheap!) retainers I could find had an OD larger than 41.6mm. I found a great model on thingiverse (https://www.thingiverse.com/thing:3691731/files), and I was wondering if it's feasible to do something like this in PLA filament. Will it melt?

 

[cwbullet]

PLA is too flexible in the summer heat - go with petg.

 

[Sparrowhawk]

I suppose I do need some new filament anyway... I’ll buy some PETG then.

Will it melt from the heat of the engine casing?

 

[cwbullet]

It will melt but I have not had it melt from the motor casing.

 

[Sparrowhawk]

It will melt but I have not had it melt from the motor casing.

Sorry that is confusing me a little. Are you suggesting that it will melt or won’t melt during a launch

 

[cwbullet]

The retainer should be mounted to a paper tube. It will retain the motor. I've never had one melt except around the end with the motor throat.

 

[Sparrowhawk]

The retainer should be mounted to a paper tube. It will retain the motor. I've never had one melt except around the end with the motor throat.

Oh when I said motor casing I just meant the heat from it going thru the mmt lol sorry if that was worded badly. So structurally it will still hold?

 

[cwbullet]

Yes. It will hold. I print with 100%i infill

 

[Sparrowhawk]

cool, thanks!

 

[swatkat]

Print solid. PETG, or PLA Pro. I've not had one fail, up through level 2 motors. One kit has Nine 38mm H and I motor launches and the outer retainer is just a bit discolored. You can always print a new outer retainer...