Strong and Flexible Plastic / Nylon : Brass Heat-Set Threaded Insert for Plastics

I am interested in using a brass heat set threaded insert in a part 3D printed in the Shapeways Strong and Flexible Plastic Nylon Material.

Here is a link to the insert that I want to use at Mcmaster.com:

http://www.mcmaster.com/#94180a363/=zh8cvk

My Question: What is the minimum temperature that I will need to heat the brass insert to slightly melt the Nylon and bond with the 3D printed part?

Why You don´t try to make the hole same as the given dimensions ?
Normally, You don´t need to heat the insert..

Possibly it is a more safe way to to heat Your Nylon in hot water (60-70°) before You hammering the insert into the polyamide.

Edit: Because the sintered nylon is porous,- You might get less grip because shrinking of the sinter material

.

I did design the corresponding 3D printed Strong and Flexible Nylon part to have the recommended taper that this brass insert requires. The threaded brass insert uses a special soldering iron tip that allows you to heat it up from the inside of the threads. Then you just gently melt it into the tapered hole. I am wondering if anyone knows what the actual melting temperature of the Shapeways - Strong and Flexible Nylon material? I can raise the temperature of the brass to just above this melt point and insert into my part. Then I can have strong brass threads embedded in my nylon part.

I appreciate your input.

Thanks,

Hey Panascape,

I've got a bit of professional experience with designing for and using threaded brass inserts in injection molded Nylon parts. The 3D printed Nylon is similar enough in my opinion.
The temperature situation is transient rather than steady state. That is, if you heat your insert to the melting temp of the plastic, as soon as it makes contact with the Nylon and you get some heat transfer, the temperature will drop significantly, and you'll be sitting there slowly warming up your plastic part to where large portions of it start to warp and not getting anywhere. The trick is to go hotter than melting, but lower than burning to avoid discoloration and fires. Luckily that window is pretty broad. The hotter the temperature, the faster you'll be able to dump heat into the plastic, melt it, and move it out of the way, and the quicker you'll be able to remove the heat source and avoid spreading the heat to too much of your part. The sweet spot you're going for is a temperature that gives you the most control during the pressing operation, 2-3 seconds to drive the insert all the way in with moderate pressure. The only thing to watch out for is driving your insert too deep. A flanged insert is a lot easier in that respect as it gives you a very definite stop to press against when its fully in.

According to the material datasheet for WSF ( https://www.shapeways.com/rrstatic/material_docs/mds-strongf lex.pdf) the melting point is around 180° C. You'll probably want to start with a soldering iron set to 200°C+ and experiment from there.

A special soldering tip is a complete waste of your time and money. Any soldering tip small enough to have it's end fit into the threaded hole will be good enough, just make sure it doesn't jam in the threads and releases cleanly. I've had a few inserts come right back out of the part when I was trying to remove the soldering iron. One trick you can try is to thread a long screw into the insert and manipulate it with some pliers with one hand while heating the screw and insert with the soldering iron with the other hand.

Hope this helps and please share how it turns out.

Euge,

Thanks so much for your very helpful explanation. I am greatly appreciative of the time that you took to write such a thorough response to my inquiry. It is exactly the kind of information that is incredibly helpful and that it is not possible to find without experience.

I will definitely post photos of the 3D printed part and my brass insert results. The Shapeways part was shipped this morning and I ordered the Mcmaster brass insert yesterday. I should be putting them together next week.

Best,

David Garden

I posted my experience with threaded inserts here:
https://www.shapeways.com/forum/index.php?t=msg&goto=139 538#msg_139538

Does anyone have any experience with the "screw to expand" inserts? This is the McMaster link to the product.

I am hoping to use these in the Strong/Flexible plastic and be able to routinely join two piece of plastic together tightly.

Good article on threaded inserts on the Form Labs website. Most of it useful to here as well.

https://formlabs.com/blog/adding-screw-threads-3d-printed-parts/