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Flush Mounted Threaded Through Hole on PCB

Flush Mounted Threaded Through Hole on PCB

Flush Mounted Threaded Through Hole on PCB


Does anyone know the name of this component of the top of their heads?

I'm working on designing a product that requires 2-56 threaded holes in a PCB, and I need it to be as flush to the surface of the board as possible due to physical size constraints. The component in the photo looks like it inserts into the through hole and solders in place--that's exactly what I need, I just can't figure out what it is called so I can order some.

Thank you in advance for the help!

RE: Flush Mounted Threaded Through Hole on PCB

Thanks for the quick reply, Dan!

We're actually using PEMNET fasteners right now, that's a great site. Unfortunately they all seem to have a lip that's about 1/8" high, and I'm hoping to eliminate that and make it as close to flush with the surface of the PCB as possible.

Someone pointed me to these, which look like they might be close enough:

Someone else mentioned that this might not be a component that was soldered in, but rather a tapped hole in the PCB that was plated.

RE: Flush Mounted Threaded Through Hole on PCB

Found this website describing your fastener:


Scroll down about 4 or 5 pictures. He states that he is simply threading (tapping) a plated through hole, and you can see in the photo that the threads are being formed in the PCB, not metal. The apparent flange of the "fastener" is just a blob of solder on the thru hole pad.

RE: Flush Mounted Threaded Through Hole on PCB

That is clearly just a regular through hole that has been tapped..

RE: Flush Mounted Threaded Through Hole on PCB

Thank you for the replies! Good find, btrueblood, that's perfect.

From the site you linked to:
The mounting holes in the PCB were sized to accept threads (0.067-inch hole for 2-56 screws). I’ve been threading holes in PCBs for many years. I assumed that the plating on the interior of the hole would be the material that would get threaded. However, now that I get a close look, I can see that the through-hole plating is lost in the process, and that the threads are made in the garolite substrate. I suspect that the threads in the substrate will have a much more limited life span of having the fastener installed and removed.

mcgyvr, you're correct. I couldn't tell from the photo if the hole was larger and the solder was just covering up the transition to the insert.

Thanks again for all the help! I think this closes the issue.

RE: Flush Mounted Threaded Through Hole on PCB

If it helps, you might be able to get the threaded hole through-hole plated as a final step.

RE: Flush Mounted Threaded Through Hole on PCB

Seems like the intended "design" is just going to have a small screw with no protrusion from the backside just barely holding something in place so even a PEM extends too far out the back..
Thats what I took away from it anyways..

RE: Flush Mounted Threaded Through Hole on PCB

Thank you all for the input!

My plan is to move forward with the MAC8 fasteners found here:

The press-in inserts btrueblood linked too look interesting, but I need to have electrical connection to these holes. I'm afraid the press-in fasteners might tear the traces when inserted.

mcgyver, you're exactly right. We're using PEM fasteners now but were looking for a slimmer option. The part is being held in place by a different feature, I just need something to thread into as an electrical connection.

Thanks again for the help!

RE: Flush Mounted Threaded Through Hole on PCB

I would never trust the glue holding copper to fiberglass to hold a board in place (which is essentially what a one-sided fastener does)... just asking for trouble in the long run.

Dan - Owner

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