Seeking bolt cutter that is flat on one side and concave on the other

I need to grind off the tips of threaded bolts with a metal grinder to make them the correct length. What I’m doing now is I’m throwing on a nut and using a metal grinder to chop off the portion of the bolt extends beyond the nut.
It’s not a clean process since my hand isn’t steady and I end up cutting into the nut, not only that, I have to brace or clamp down the item.
The problem with a regular bolt cutter is it won’t cut flush to the nut. I’m wondering if a bolt cutter exists that will cut flush to the nut?

 

Use two nuts and jam them tight together, Then use a hacksaw to cut off the bolt.

Or

Install a nut past where you want to cut off the bolt. Mark the bolt length to the nearest thread and cut off using a hacksaw following the angle of the threads. Turn off the nut to clean up the threads.

 

I’m doing something similar to that now, would like to save the trouble of clamping and sawing , if I can

 

You can cut the bolts to length before installing them. That way you can do it in a workshop where the conditions are more controlled and you can grind the end of the bolts square & pretty and put a nice chamfer on the end so the nuts start easily.

The most common method is to just use a grinder or cutoff wheel. Like anything you'll get better with practice. Sometimes hitting the cut end with a sander can clean up the cut and make it look a bit more presentable.

Then there is the manual hacksaw. It's much slower so you can have more control and may be able to make a neater cut than the grinder. You could also try a fine tooth metal cutting blade in a reciprocating saw. Still, I'd pick the grinder or cutoff wheel first.

 

I don't think OP mentioned the size of the bolt being cut, but for machine screws no larger than a #10, I used wire strippers similar to the one below. Run the screw in the threaded side of the stripper, close to cut the screw and removing the screw chases the threads. Easy to reproduce matching screw lengths.

If larger than #10, Post #2 is best.

 

1/4" bolt but I got a bunch of 1/8" thick washers from Grainger and I can use them to take up the space prior to the cap nut fitting over it.