1" ID EMT Conduit Plug

I mostly deburred my pipe-cutter cut pipes, but there was still a bit left to make it narrower, so this is 25mm instead of 25.4mm ID. It will be a little loose on factory cut ends. 

If it's too tight/loose, you can scale it in your slicer, or modify parameters in the Fusion file.

Or a couple wraps of electrical tape will fatten it up to fit. 

Attached to my V1 Engineering Lowrider 4 CNC (v1e.com, lowridercnc.com)