What is the purpose of this disk over a Samtec connector?

Question

With beautification in mind I decided to attach 3D-STEP models to elements on my PCB.

One of them is a connector from Samtec. They do provide a STEP models for a download, but it was immediately suspicious to me, that the preview had this weird disc over the connector. At that moment I thought it was some kind of glitch and proceeded downloading STEP model regardless.

See the image below:

Attaching the downloaded STEP model I was surprised by this disc again. Turns out, it was also exported into STEP model along with the connector. Unfortunately, this serves bad for the purpose of "beautification" :)

Questions are:

What is the purpose of this disk?
Is there any way to download a STEP model of Samtec connector without this disk?

For a reference, the connector is QSH-030-01-F-D-A-K

Now that you know what it is, their website lets you disable the "pick-n-place" pad when generating the model :) — crasic, May 25 '20 at 20:05
@crasic Really? I couldn't find anything, that disables it. It has a listbox of download options and "Download" button. — PF4Public, May 25 '20 at 20:11
To do that, you need to visit the page with the generic series, not with the specific part number; check out https://www.samtec.com/products/qsh — Vladimir Cravero, May 27 '20 at 05:32
@VladimirCravero That was already obvious after Mast's answer. — PF4Public, May 27 '20 at 08:45
Now that you have accepted it, and it is on the top of the list, it is obvious to me as well :). — Vladimir Cravero, May 27 '20 at 09:41

score 45 · Answer 1 · edited May 26 '20 at 08:43

45

That orange disk represents a pick-and-place sticker—it provides something for the pick-and-place machine's vacuum head to grab onto. Without this, you'd have to assemble the connector by hand.

Here is an example photo of a similar Samtec SS4 with the vacuum pick and place sticker in place:

edited May 26 '20 at 08:43

Cody Gray - on strike

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answered May 25 '20 at 20:10

Jeroen3

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Mast · Accepted Answer · 2020-05-28T06:33:47.877

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This hasn't been explicitly mentioned yet, but you got a disc because you asked for one.

It's a Polyimide film pad, and specified by the last code in your part: -K. The purpose of this pad is so the vacuum pick-and-place machine has something to hold the component on. It needs a flat surface big enough for the vacuum head, as already shown by Jeroen3 and DKNguyen. For manual manufacturing, you don't need the film pad. But some automated lines can't pick up the parts if there's no flat surface provided.

QSH-030-01-F-D-A-K has the pad, QSH-030-01-F-D-A does not.

030-01 says how many positions and the lead style. The other codes:

-F: 3u plating
-D: double rows
-A: alignment pins
-K: Polyimide film pad

See the QSH configurator. Find your new, padless STP files there too.

Polyimide (also known under the brandname Kapton) is stable for a wide temperature range and a good electrical isolator, making it ideal for this purpose.

edited May 28 '20 at 06:33

answered May 26 '20 at 10:09

Mast

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Just what I was about to say. I love the Samtec part configuration abilities. – SiHa May 26 '20 at 10:16
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Aha! This answer adds some additional info on top of what the higher-rated ones have. +1! – akwky May 26 '20 at 12:35
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So the answer is "you got a disc because you asked for one". Now I feel stupid :( That must have been a punishment for blindly copying the connector from an evaluation board. – PF4Public May 27 '20 at 08:51

DKNguyen · Answer 3 · 2020-05-25T19:46:23.090

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It is a place for the pick-and-place machine's vacuum head to grab onto.

Taken from Adafruit

edited May 25 '20 at 19:46

answered May 25 '20 at 19:15

DKNguyen

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It really sucks – May 25 '20 at 19:52
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It's vacuum. There's nothing to it. – Transistor May 26 '20 at 10:15
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@Transistor: But you still have to pump vacuum into the chamber (yes, operators in a [sugar refinery](https://en.wikipedia.org/wiki/Sugar_refinery) actually used jargon like that) – Peter Mortensen May 27 '20 at 12:41
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@PeterMortensen Well...we have hole flow so........... – DKNguyen May 27 '20 at 14:53

Spehro Pefhany · Answer 4 · 2020-05-25T19:53:24.393

The polyamide pick and place disk is part of the assembly as defined.

If you have a 3D CAD program that uses of one of the very many supported formats you can simply open the file and delete the disk, then save it as an AP214 .stp file.

Otherwise you are at the mercy of whoever is creating these files and the options they happen to offer.

You can probably find a demo or free version of one of the supported pieces of software.

What is the purpose of this disk over a Samtec connector?

4 Answers4

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