# 3D Printing > 3D Printer Parts, Filament & Materials >  what the best filament for printing "joints"..??

## Verwijs

*Question*: what the best filament for printing joints like _"Snap-Fit"_  joint..??
(or other ways to fit objects together)  standard PLA  
has a LOT of shrinkage and is very hard so parts don't fit.... 

link to blog with examples:
http://eikimartinson.com/engineering/3dparts/

example snap-fit joint...

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## Ama-fessional Molder

You can use almost anything if your design accounts for the mechanical properties of the material. If you have a very flexible material, you would want a short arm on the snap lever. If it's very rigid, then you'd need a longer one to allow the part to flex.

Also, PLA has a very low shrinkage compared to nearly any other material. Every plastic shrinks, PLA is about the least, and you will always need to account for this in your design dimensions.

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## ralphzoontjens

Yes PLA works great for snap-fits! As long as you maintain proper printer settings it will be quite dimensionally accurate.
Also annular snap fits work great. You can build fully articulatable action figures with plenty of snap features and hinges and the product can still function nicely.
The main thing is feature size with 3D printing, the snap fits will have to be much larger than injection molded snap fits.
Also see if you can orient the print so that the layers get printed along the snap beam, and not across it. If that is not possible there are Cura scripts that allow you to print layers not flat but for example at an angle or in a saddle shape across the print, which drastically increases strength because the interlayer forces are spread more.

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## Verwijs

Thank you for reply,  I'm using M3d Micro with standard PLA..  
I'm going to try  *Octofiber* PLA, to see if this gives me  better results... 
and maybe M3D *ABS-R*  filament (didn't try yet).  A post about it here: http://goo.gl/GLKJno

 for this you need a filament witch is tough, but has slight bending properties.... 
(without breaking  :Smile:  ) 

André

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## curious aardvark

> standard PLA  
> has a LOT of shrinkage


standard pla has ALMOST NO shrinkage. You are thinking of abs. 

petg is your best choice, with a good pla or pla/pha close behind. 

I've found that the pla I use is much better for a tight fit than the abs I've used for the same part. 
It's not what everyone else will tell you. but with the same part I always found that abs would break and pla would snap in. I now use polyflex for the part and it can't break :-)

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## Ama-fessional Molder

> standard pla has ALMOST NO warpage. You are thinking of abs. 
> 
> petg is your best choice, with a good pla or pla/pha close behind. 
> 
> I've found that the pla I use is much better for a tight fit than the abs I've used for the same part. 
> It's not what everyone else will tell you. but with the same part I always found that abs would break and pla would snap in. I now use polyflex for the part and it can't break :-)


You mean shrinkage.

As previously mentioned by Ver, stiffness is key to a good snap fit. You want the bare minimum amount of flex required to snap into place, and maybe a little more to facilitate disassembly in the future if required, plus a little margin of error so that the tab stays in it's safe flex window without being too easy to disconnect.

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## curious aardvark

yes but was using the same word the person did :-)

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## Ama-fessional Molder

Did you REALLY?




> standard PLA has a LOT of shrinkage
> 
> 
> standard pla has ALMOST NO warpage.

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## curious aardvark

well sometimes they change their words :-)

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## Ama-fessional Molder

Nobody here did so. Just admit that you can't read in the mornings.

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## Davo

Just mornings?

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## NaotoSakaue

Plead see this post about NANODAX's glass wool filled PP filament. "Z-Temp Forum"
Maybe this new material is suitable for your requirement.

←My profile says I am a student. But I am an old man. :Wink:

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## curious aardvark

lol - nah they definitely edited their post after I read it. 
Everyone knows I'm completely infallible ;-)

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## Ama-fessional Molder

Ohh, my mistake then CA.

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## curious aardvark

lol - well if you will be so pedantic :-)

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## Ama-fessional Molder

I enjoy accuracy.

If that means I am wrong and need to be corrected, even better.

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## curious aardvark

lol - I even quoted the guy above my reply.

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## infinity3dprinting

You can use PLA Filaments. PLA Filaments are strong, rigid and it is easy to work with in complicated interlocking assemblies and pin-joints. We have PLA Filaments in Australia.

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