I was wondering if anyone had any experience in this area and if they could recommend a resin that would provide the proper friction needed to keep snap-fit joints tight?
Thanks
I’m not sure about FormLabs resin, but I’ve used the ApplyLabWorks Olive-Gray (Modelling Plus) resin to make ball and socket joints, and it works quite well.
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Formlabs resins would be tough or durable. I would use durable to make the ball and socket easier to install.
A little heat on the socket side would also help assembly.
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Tough Resin tends to work best for snap-fits and we have a new White Paper on Engineering Fit that you might find helpful.
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Thanks and will Give it a try.
This sounds like what I’m looking for but how is the friction on the socket with a limb attached?
Appreciate the recommendation.
Thank you all for getting back to me so quickly.
Are you planing on prototyping something that you will manufacture later from a different material – or is your intention to have the printed parts be the final parts?
No matter what material you use you will need to prototype a few different fits to get the feel you want. The material used and even a bit of printer to printer variation can have some effect.
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Just a word of advice, from personal experience. Getting the fit to be nice and smooth when you test fit the 2 parts is not always desirable, especially if those joint are going to be supporting something heavier up above.
I had this happening to me when I was building my Imperial Knight. The hips and knee joins were smooth and could stand on their own, but once I added the weight of the main body on top, the model could no longer stand on it’s own, it would collapse at the joints.
So you can make your joints a lot tighter, or you will have to get creative with means of locking the joint in place once it’s posed.
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Actually both…but It’s starting to seem like that’s asking a bit much.
I kind of figured that could be an issue. I’ve created several versions of joints with different textures and what I like to call friction plates. My biggest issue will be the figuring the proper gaping for the joints since I’m a ZB user and getting it precise will be a must. Are there any concerns with resin shrinkage or bloating VS what you model?
Prototyping different parts for my desired outcome is not so much of a problem VS using different printers. I was hoping I’d be able to manage all of my printing needs from the Form 2 with the combination of different resins.
My experience with resin to resin friction joints (grey and black) is that the tightness lost very quickly with any regular use. They will become loose within the same day if I do a lot of posing.
I have read a lot about tough and durable resins, is there any reason to believe they will last 100x, or 1000x longer than grey/back do? I think for the end product to be a printed part, this level of improvement in friction wear is needed but I have my doubts that tough or durable are anywhere close to that.
For me the only solution to printed part friction joints is to incorporate a stronger material (metal parts) to bear the friction.
I would love to hear any experiences where tough or durable contradict my beliefs! 
Durable/Tough can’t go as small scale as the standard resins but they help. Walls need to be a bit thicker to remain rigid.
Tough is good but you get white dust from the parts rubbing
Durable has been amazing so far- I’ve not tried to paint it yet though. The sample they give you is literally a ball joint with a screw to add variable friction.
I never worried about shrinkage and such, and as mentioned elsewhere I tried a bunch of variations from the tightness of the joint, to doing textured surface . None lasted more than a few minutes of movement.
Ultimately, the only thing that worked for me was to install a grub screw in the socket, that could be tightened against the ball.
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Not to discredit anyone else here but you seem to have a lot of experience for what I’m aiming to accomplish. I want to run an idea by you and whoever else is in this thread. The Joints I’ve designed are modular to fit a line of character sculpts (which is the norm)…so what if I combined the rubberlike attributes of flexible resin with a grey/tough to help with friction? Standard barbell ball joint (tough resin) and the receiver which would be a plugin to the sculpt itself made out of flexible resin? Is this something you’ve thought of or tried?
Are you talking about a regular resin socket with an inner flex resin sleeve?
Never tried it, but in retrospect it might work. You’ll want some flexible/elastic/compressible resin, but this would be a design I would try:
Let’s say this was an arm and wrist. The wrist has the ball joint, and the arm has a square receptacle. The middle piece is made from flexible rubber, and has the socket for the wrist ball joint… You first snap the rubber piece over the ball joint, then you insert the whole thing into the arm receptacle, which is slightly undersized. Because the insert is rubber-like, it will compress and fit tightly into the receptacle, and at the same time it will apply even, all around pressure on the ball joint.
Give it a try. Who knows, it might work.
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Exactly!
Thanks for the assist.