how to align edges of object against cylindrical pins

[jonboste]

Hello Everyone

Im struggling with an alignment task of two objects, using the A2plus V0.4.47 workbench.

I have this big plate, labelled R1H0S, which has 3 protruding cylinder pins used to align the smaller green pcb against.

So im trying to align the smaller green pcb, such that its edges push against the 3 alignment pins.

I can roughly do it through manual movement of the green pcb, but that is not accurate enough for my needs.

I did without problem a PlanesCoincident constraint between the top surface of the big jig and the bottom surface of the green pcb, but I can't figure how to align the edge planes / edge lines with a tangent coincidence to the cylinder pin face.

pcb-align.png (20.35 KiB) Viewed 940 times

Freecad version:

OS: Ubuntu 20.04.4 LTS (ubuntu:GNOME/ubuntu)
Word size of OS: 64-bit
Word size of FreeCAD: 64-bit
Version: 0.19.24291 (Git) AppImage
Build type: Release
Branch: (HEAD detached at 0.19.2)
Hash: 7b5e18a0759de778b74d3a5c17eba9cb815035ac
Python version: 3.8.8
Qt version: 5.12.9
Coin version: 4.0.0
OCC version: 7.4.0
Locale: English/United States (en_US)

[chrisb]

Moved from Help forum.

[dan-miel]

I can't figure how to align the edge planes / edge lines with a tangent coincidence to the cylinder pin face.

jonboste:
Here is a workaround if it is close enough. I made a half pin the same size as the pins on the plate, then attached them to the top of the existing pins using a coincident and axis to axis constraints. I then made the flat surface of the half pin parallel to the sides of the plate. Lastly, I use the "point to surface" constraint to connect the point of the half pins to the edge surfaces of the board.
Hope this helps.
Dan

OS: Windows 10 Version 2009
Word size of OS: 64-bit
Word size of FreeCAD: 64-bit
Version: 0.19.24267 +99 (Git)
Build type: Release
Branch: Branch_0.19.3
Hash: 6530e364184ce05ccff39501e175cf2237e6ee4b
Python version: 3.8.6+
Qt version: 5.15.2
Coin version: 4.0.1
OCC version: 7.5.3
Locale: English/United States (en_US)

[jonboste]

Dan-miel:

Thank you very much for the quick reponse, this works for me!

Cheers!