Doing up, and undoing nut's and bolt's

Good point. Sometimes the "lead in" is more trouble than it's worth. When shortening bolts I normally wind a nut down the thread, cut the bit off and wind the nut off the thread again. This at least ensures that any distortion at the cut is corrected. A brief whizz around the end with a file takes off any burrs. Almost always works well.

+1, but use the file before you remove the nut.
 
+1, but use the file before you remove the nut.

And +1 to that.
If shortening a fastener, rotating it so that the cut is 'out-to-in' at all points on its circumference produces much less of a troublesome burr. I generally use a cutting wheel in a Dremel (or 1mm cutting disc in an angle grinder for larger fasteners), but there's no reason a hacksaw can't be used in the same way.
 
I wonder if anyone makes a conical (concave) grinding wheel to deburr the end of a screw thread? I usually use a die, set loose to pick up the thread initially - sets can be had quite cheaply from the likes of Toolmart.

I have often found that in awkward positions/orientations it really does help to close my eyes, somehow removing the visual distractions simplifies the task.

Rob.
 
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