Stainless Steel M4 heat set inserts for 3D printing?

[awemawson]

I've just completed some adaptors for an EDM machine that incorporate brass M4 heat set inserts. It all works but I'm concerned that they won't last long as it's flooded with de-ionised water which will disolve them eventually.
The plan is to re-print when that happens but this time with Stainless heat set M4 inserts BUT I can't seem to source any - does anyone know a source?

 

[fizzy]

https://tinyurl.com/4s4yaraf

ali express

 

[hotponyshoes]

I've got some PEM ones, how many do you need?

 

[awemawson]

That's very kind, I only need 6 (if I don't cock it up!).

But I have to ask, what is PEM in this context ?

 

[bigegg]

Can you adapt the design to use SS nuts inserted mid-print?
Or post-print, epoxied in?

 

[hotponyshoes]

That's very kind, I only need 6 (if I don't cock it up!).

But I have to ask, what is PEM in this context ?

Pem is the brand, just mentioned it so you can check the dimensions are suitable

 

[Agroshield]

Pem is the brand...

I think this is the page:

https://www.pemnet.com/eu/products-overview/products-threaded-inserts/threaded-inserts-ultrasonic-heat-staking-inserts/

 

[Bladevane]

@awemawson - I've just watched a fascinating tutorial about adding ribs to a hole such that the male fastener can screw into the printed item without the need for threaded inserts. If the part is long enough this may be right up your street. The article was concerning FreeCAD so I don't know whether this is a thing with all CAD packages.

 

[hotponyshoes]

@awemawson - I've just watched a fascinating tutorial about adding ribs to a hole such that the male fastener can screw into the printed item without the need for threaded inserts. If the part is long enough this may be right up your street. The article was concerning FreeCAD so I don't know whether this is a thing with all CAD packages.

You can print threads directly pretty successfully.
Or you can just print a hole the right size, heat the bolt/screw and wind it in.
Or print a solid area with a pilot hole/center dimple in the right place then drill & tap it.

The inserts are used for durability (when you plan to remove/refit the bolt), For higher loads (as the o/d of the insert is bigger than the bolt) and for ease/adjustability of design.
I also use them on printed materials that won't take/hold a thread like tpu, pcl etc.

 

[awemawson]

In my case it's part of a mechanical tool (a Wire EDM machine) and needs to be fixed pretty rigidly although there is minimal load on it. For this reason I've run bolts through the part to inserts on the far side hence the part (which is 20 mm thick 99% fill) is being squashed. My only concern is longevity as it runs liberally covered in de-ionised water, which has a habit of disolving stuff.