I know there are lots of great smiths who could handle this for a relatively small fee, but I like to tinker once in a while. I used an old manual millrite mill, then clamped the bolt in the mill vice using v-blocks and did my best using levels to get the bolt handle "plumb" (actually wanted the back side of the handle to be plumb, not the front). Then I used an end mill to cut the knob off down to a 5/16" square to save some boring time. Next I used a boring head and turned the cutter backwards taking off about 10 thousandths per pass until I had a nice cylinder of 5/16" diameter. Once I had all the corners rounded off I used a die to cut the 5/16-24 threads and finally used a small amount of heat and dipped in motor oil to refinish it black. I bought the knob itself from a local smith who builds them on his CNC machine.
This is the second one I did, the first one didn't turn out quite as well, imagine that.
But interestingly I discovered that R700 bolt handles are not hardened steel, the TC venture that I did first, was hardened steel, so I actually had to temper the steel first in order to machine it. If you are doing any bolt handles you might think about what type of steel you have to start with. If you're not sure, running a file across it would tell you pretty quick.
I'm very happy with how this turned out, especially considering I did it myself.
This is the second one I did, the first one didn't turn out quite as well, imagine that.
But interestingly I discovered that R700 bolt handles are not hardened steel, the TC venture that I did first, was hardened steel, so I actually had to temper the steel first in order to machine it. If you are doing any bolt handles you might think about what type of steel you have to start with. If you're not sure, running a file across it would tell you pretty quick. I'm very happy with how this turned out, especially considering I did it myself.
