Has anyone got a single 2" long 5/8" BSF grub screw I can exchange for currency? My local (usually pretty good) fastenings stockist is unable to come up with the goods. If I really have to I can die sink a hex socket into a bit of HT 5/8" BSF studding cut from a bolt (that I'll have to buy from them) but I'd rather not as it means the bore of making a tool.
(This is a pivot adjusting screw on an Edwards 4 foot x 14 gauge box pan folder I am resurrecting)
I recently made two brass carb jets that need a hex recess and tight-fitting key to hold them in place while being installed. The tooling I made to broach the hex consisted of a 6-hole sheet metal index disk bored to fit my lathe's spindle thread, secured by the collet holder removal nut, and a hex key one size smaller ground flat on the end.
I held the disk in each of the 6 positions with a cobbled-up index pin made from brazing rod and broached out the hex at 0.001" per hand-fed cut with the sharpened hex key in a boring bar holder. The key cuts with the angle that's toward the operator and set to center height. After a few passes all around I ran in the shop-made 90-degree-point D bit, which originally formed the recess and the lead-in to the metering hole, to knock off the shavings.
6 index holes around a circle is very simple to step out with dividers still set to the radius of the circle, in case you've forgotten your Euclid.
If the chosen high tensile steel is too difficult to tap, maybe you could machine or grind a male hex section on the end and use a modified socket head cap screw for the wrench. Then you could shape it with a carbide flycutter and not risk a more delicate and expensive tool. jsw
Thanks chaps for the suggestions, but if I end up having to put a hex recess into the end of the HT stud, I will use my die sinker EDM machine as the tooling just needs to be a copper or graphite hex with a hole down the middle for flushing. I might even get away for a one off with a bit of hex brass bar :)
"Andrew Mawson" wrote in message news: firstname.lastname@example.org...
Nice that you have it. We have to make assumptions when someone asks how to do a simple operation, such as that they are an amateur with only a hobbyist lathe and/or mill. I have a surface grinder but rarely suggest an answer that needs one. jsw
Well I don't know why I didn't suggest just pulling out your EDM. I mean that's what I would do . If I had an EDM machine. EDM would make a nice and easy job for making the female hex shape. Cheers, Eric