Happy New Year to all

The sliding rails on the attached picture are about 2” longer than I wanted. I tried to cut off the extra length with a hacksaw but did not even make a mark on the round part.

Perhaps a reciprocating saw may do the job?

That stuff is hard to about 1/16" or so deep, then it is softer.
I grind all the way around with a cut off disc about 1/8" deep then saw it.
Or just cut it off with the disc in a hand grinder. If you have one big enough.

Thin Cutoff disk in a cheap 4" hand grinder will do just fine.

(;-)TP

Great idea, thank you both

You might want to wrap it with a wet towel to keep it cool while cutting.

Or use a masonry type petrol cutoff saw with water feed, these are great for keeping dust down and should help with cooling.

I will use a Cutoff disk in a cheap 4" hand grinder which I have and wrap the rest with a wet towel

4"  disc angle grinder is good in use. Personally, I made an holder for it in the Z- slide of my router, so different type material can be cut with nice cut efge or surface by reciprocating the x or y axis motion. Taking care to have less in depth of cut, to have  thru' cut at both ends, enough surrounding safety shield on your machine.

Coolant flood as well.

Very good idea Raychar, thanks