Test jig with SMT spring-loaded pins

[mssp]

For a jig testing a very thin PCB, I plan to use spring-loaded pins that can be automatically assembled, such as https://jlcpcb.com/partdetail/Xinyangze-YZP0652_1507201/C5157254

- As far as I know, P100 pogo pin are typically used for such a task. Any reason why SMT pins should not work?
  - the test points have ENIG surface
  - the lower force of about 50g should be ok
  - the precision of the pin is anyway higher compared to P100
  - to keep deformation of the jig-PCB minimal, there is direct mechanical support on the backside of the pins
  - there are no receptables, so the pins cannot be easily replaced. That's ok because the jig-PCB is cheap enough.

- Are there any positioning pins which center the PCB-under-test that can be automatically assembled?

[thm_w]

Not really any reason other than the throw tends to be less, and mechanical strength will be a lot lower. Jigs tend to get abused. With a through hole pogo sockets, you can swap out the pin with a new one quickly.
Any part number for the pins you plan to use?

You can google SMT guide pin and find some options:
https://www.mill-max.com/products/new/sure-hold-surface-mount-pcb-pins
https://www.fivetk.com/product-category/by-category/smt-series/smt-guide-pin/

[mssp]

thanks for the confirmation, I agree with your points. I plan to use https://jlcpcb.com/partdetail/Xinyangze-YZP0652_1507201/C5157254 They allow a tight placement of test points. Should they be mechanically too unstable I can glue them to the PCB.

For the guide pin, I have used so far GP-1S. Those are also spring-loaded what is definitely preferred as the guide pin and pogo pins get lowered manually onto the thin PCB. The issue with GP-1S is that they cannot be assembled automatically (or I wouldn't know) and they require like 30mm of free space on the other side of the jig-PCB. The linked guide pins are all rigid=non-spring-loaded or did I miss something?

[thm_w]

Don't get too obsessed with automated assembly.

You could add springs to the locating pins, or use the SMD pogo pins as the balancing springs and have them evenly around the PCB. Or just use standoffs which fit into the board holes, if the tolerance is not too critical.

Without reasoning as to why you need to make it so compact and maybe some example photos, there is not much to go on here.

https://smdprutser.nl/blog/build-your-own-testingprogramming-jig/
/0]https://www.testfixtures.com/mechanical-test-fixtures/#iLightbox[gallery_image_1]/0