3D Printing Engine retainer

[crossbound]

Has anyone tried to 3d print engine retainers, and if so, what material. How reliable are they. Any melting issues? I was thinking of maybe trying PETG.

Thanks in advance.

 

[frogglicker]

I have used 3D-printed retainers exclusively for two years. I have used PLA and PETG, but would recommend at least PETG. The caps do take a bit of heat (so I have extras) but I have never had any failures. 18mm - 54mm.

 

[crossbound]

I have used 3D-printed retainers exclusively for two years. I have used PLA and PETG, but would recommend at least PETG. The caps do take a bit of heat (so I have extras) but I have never had any failures. 18mm - 54mm.

that's great! thank you

 

[Huxter]

I love 3d printed engine retainers! I've only printed them in PETG. They hold up well, altho I have little experience with longevity of them.

I have a Boosted Bertha that has retainers in both stages. The upper stage retainer got a little bit fried with an E engine exhaust started the second stage. But Hey! I can print the female end again easily!

I only use epoxy to mount them to tube. Make sure they screw together nicely - it took a few attempts to dial in the size I wanted and get them to screw nicely together.

Now I print 18, 24 and 29 mm retainers in black, red, yellow PETG.

Don't get me started on baffles!!

Good luck!

 

[jdsmith39]

I've been printing my retainers with ASA. It has worked great for several years now. I mainly do 18, 24 and 29mm. Though I have a couple 38mm.
I suspect petg would work for most, but it depends on the motor propellant.

Pla I would avoid. Can't handle the heat. Did a single qjet white lightning and it melted.

Side bonus: ASA is lighter than the petg and pla materials.

Main issue with ASA is, it is highly recommended to have an enclosure for many reasons. If you do not have one, use petg and replace as needed.

 

[crossbound]

inting my retainers with ASA. It has worked great for several years now. I mainly do 18, 24 and 29mm. Though I have a couple 38mm.
I suspect petg would work for most, but it depends on the motor propellant.

Pla I would avoid. Can't handle the heat. Did a single qjet white lightning and it melted.

That's great. Just started a print in PETG. My setup is pretty basic. Just an Ender 5 Pro and no enclosure.
I wIll let you all know how it went.

 

[crossbound]

Thanks everyone for your input. First retainer print was a success. Might play with the tolerance a little bit.

 

[Hammster]

Thanks everyone for your input. First retainer print was a success. Might play with the tolerance a little bit.

That looks great. What adhesive do you use to attach them to the tube?

 

[Zyzzyva1000]

That looks great. What adhesive do you use to attach them to the tube?

I also 3d print all my retainers. Standard 5 min epoxy seems to work great. As someone further up the thread mentioned, ASA is a great material for these. I have some big 54 and 75 mm retainers that have held up fine. Sometimes the outsides melt a tad if the blast plate is close - but usually its just the paint that's affected.

 

[SolarYellow]

I have a rocket based on the Estes Booster-55. Because I can, I lightened up the threaded retainer cap on the lathe, shaving thickness and tapering the opening a little. Was quite surprised to find the rocket fully intact, with a successful deployment, and no motor present. I concluded that the heat had softened the reduced-thickness polystyrene cap (softens about 212* F or so) enough that the D12 was ejected at the same time as the laundry. The cap went back to its original shape and cooled on the way down.

 

[cwbullet]

Has anyone tried to 3d print engine retainers, and if so, what material. How reliable are they. Any melting issues? I was thinking of maybe trying PETG.

Thanks in advance.

If you design it, upload and share the STLs. We would appreciate it,

 

[Jon Fox]

That's all I ever use. I wrote a parametric rocket parts generator that includes support for three different styles of threaded retention: Engine tube, inner body tube, and outer body tube. Also includes mason-jar style retention plates for parametric threaded retention of clusters.

https://makerworld.com/en/models/518481

Threaded cluster retention: