Metal bifold doors with top and bottom tracks - what pins?
Thanks for posting. We need just a little more information. Can you tell us the diameter of the pins, as well as the diameter of the caps atop the pins? And is there any manufacturing information on the door you can show us a picture of? We'll do our best to assist from there.
The brims of the caps are 5/8 and the smaller part of the cap is 3/8
There are no manufacturing marks.
The conical springs seem to be 2 inches tall.
Perhaps I can help. It looks like you have the old style Slimfold bi-fold doors. I pulled up all the related parts that go with your doors. If you are replacing the tracks, look at the 21-401 3' track, as well as the other sized varieties I have listed on this page. For the bifold pins, you will need one bottom threaded pivot pin, the 21-001; for the other three you will use 21-007. Please review.
The springs are in fact included with the 21-007 Guide Pins.