[bridkarl]

In the course of a radio repair job I had
to replace some threaded rod that was holding on a part.
I cut the rod with a hacksaw which made it hard to thread a nut on it. Is there a tool or method that doesn't mess up the threading when cutting threaded rod?

[klondike98]

When I've had to do that I almost always have to look closely at the threads after cutting and file the end a bit to recreate a smooth thread for the nut to go on. I've also read that if you tighten two nuts onto the threaded rod just above where you want to cut and the after cutting undo the nuts it can help smooth the threads out but I've not actually tried that.

[morzh]

Yes there was a tool, for smaller screws. It is a two-handel plier-like tool. It has sheering action, and so cut flush; the screw is first screwed in one of the jaws and then cut; then it is unscrewed and this straightens out whatever damage was done (little as this is sheering).
https://www.ebay.com/itm/147106390025?ch...=view_item
Of coures it is always desired to taper chamfer the tip, but it works without it too.
There are power tools also. But they are bulky and won't necessarily fit into the space you workin with.

[MrFixr55]

I use a combination of methods:

Thread nuts on the rod before cutting
Cut with a Dremel tool.
Chamfer the end.
Back the nuts off.

[DaleHCook]

I use a combination of methods:

I do the same with one additional step - I use a die (from my large tap and die set) to make sure the threads are clean and straight.