Automatic Heat-Set Insert Holes for Standoffs

[danyvanimpe-lab]

First of all, thanks again for all the work you're putting into Layerling. It's great to see how the project keeps evolving.

While designing electronic enclosures, I thought of a feature that might be useful for some users.

Many electronic projects use standoffs with heat-set inserts for M2, M2.5, M3, or M4 screws. At the moment, the user has to manually create the correct hole diameter and depth based on the insert specifications.

I was wondering if it might be interesting, at some point, to have an option that automatically creates the proper hole inside a standoff for a selected insert type. For example:

• Select insert type (M2, M2.5, M3, M4, ...)
• Automatically create the correct hole diameter
• Automatically create the correct hole depth
• Optional blind or through hole

I've attached an example image of an electronics enclosure where this type of feature could be useful.

This is just an idea from a practical use case, not a feature request I'm expecting to be implemented. I simply thought it might be useful to mention.

Thanks for considering it, and thanks again for your continued work on Layerling.

Best regards,
Dany

[AkiraNorthstar]

Yes, this would be fine!
There should also be the possibility (as with the screws) to add the clearance.
But each provider has its own peculiarities...
Mine are from "ruthex" and "CNC Kitchen", as they are cadmium-free / lead-free.
Both companies provide the CAD files for the heat inserts.

CNC Kitchen - Heat Set Inserts CAD Models (STL and STEP):
ruthex - Heat Set Inserts:

[henmedia]

@danyvanimpe-lab, @AkiraNorthstar, thank you both, this is clear now, and a workflow is a better thing to think about than a library.

What works today: a Cylinder set as Hole, sunk into the standoff with the diameter and depth you type. Nothing sets the size from the insert yet, and nothing puts it in the middle of the standoff for you; the Screw hole shapes (counterbore, countersink) have free measures as well.

I have noted the idea in the form you describe: choose the size, which fills diameter and depth as a suggestion, keep both editable, a clearance field, blind or through. To judge the suggested values it would help to know what you use today: for M2, M2.5, M3 and M4, which hole diameter and depth do you drill or model for your inserts (ruthex or CNC Kitchen)?

[danyvanimpe-lab]

Most users probably buy generic heat-set inserts from Amazon or similar stores, as I do. My idea is mainly about simplifying the workflow: selecting an insert size and automatically creating the correct centered hole and depth in a PCB standoff.

[henmedia]

@danyvanimpe-lab, thank you, the picture helps: such inserts are named by thread, length and outer diameter (M3 × 5 × 5, for example), and the outer diameter follows the thread (3.2 for M2, 3.5 for M2.5, 5 for M3, 6 for M4, 7 for M5, 8 for M6). That fits what you describe: choose the size, and the diameter and a usual length come as a suggestion that you can change, with the hole a little smaller than the outer diameter by a clearance you set.

One more thing that would help to judge it: for an insert such as M3 × 5 × 5, how much smaller than the outer diameter do you make the hole, or what diameter do you give it?

[AkiraNorthstar]

I hope it helps...

[henmedia]

@danyvanimpe-lab, @AkiraNorthstar, thank you both, the two sheets answer it. They agree on three things: the hole is about 0.4 to 0.6 mm smaller than the insert, it is at least the length of the insert plus 1 mm deep, and the plastic around it needs a minimum wall (1.3 mm for M2, 1.6 for M3, 2.1 for M4, 2.6 for M5, 3.3 for M6). From the wall, a standoff diameter follows: the hole plus twice the wall, which is what you meant, @danyvanimpe-lab, with enough material around the insert.

So a choice of the size could suggest the hole, its depth and the smallest standoff, all of them changeable, with the clearance you set. The two makers differ by a tenth of a millimetre, so the suggestion would be a starting point and not a rule. I have noted it that way.

[danyvanimpe-lab]

To be honest, I don't use a fixed rule for that.

Most of the heat-set inserts I use are generic inserts from Amazon, and I usually follow the dimensions recommended by the seller or test them in a small sample print.

That is actually one of the reasons why I thought this feature could be useful. The workflow is more important to me than a specific hole diameter.

My idea was:

• Select an insert size (for example M3 × 5 × 5)
• Place it on top of a standoff
• Layerling automatically centers it
• Layerling automatically creates a suggested hole diameter and depth
• The user can adjust the clearance if needed

Different insert manufacturers, materials and printers may require slightly different hole sizes, so having a suggested value plus a user-adjustable clearance would probably be the most flexible solution.

The inserts I use are generic Amazon heat-set inserts similar to the assortment shown in my picture.
What I also meant with this idea is that it could help users create standoffs with enough material around the insert.

For example, if I choose an M3 insert, Layerling could suggest not only the hole diameter and depth, but also a reasonable standoff diameter so the insert remains well supported.