Silly me, I just ordered a new frame from UDC and realised that its too large for my seat post without a shim. My post is 22.2 and the frame is 25.4 meaning I need a shim of 3.2.
However, it seems UDC is out of shims of that size. So what would work as a Temporary shim until I could by one from UDC or elsewhere?
Beer can? Hockey Stick Tape?
I wouldn’t use the tape, it’ll compress and not work well. Aluminum cans used to be the cheap shims of choice for the trials riders back in the day, go with that.
+1 on this.
Just check periodically that your shim hasn’t deformed or moved from where you first put it… you can end up deforming your frame in the process.
Tried a beer can it did not work very well. Could not get the thickness required. Tempted to try a tin of beans.
Maybe I’ll just send the frame back and get it exchanged. 
Get a new seat post.
i’ve used electrical tape and it worked really well
I would get a new seat post…
Seat post on order.