Quote Originally Posted by metric_taper View Post
Toolmaker; My cheap 4x6 bandsaw was made in 1976 in Taiwan, when they were still making mass produced junk. Still see the same design errors in new ones. That original tensioning bolt was a cheap hex bolt with a knob molded onto the hex head.
I used 7/16" O2 round stock to make the replacement, I changed the thread from metric to inch standard as I made a new female mate (as it was in bad shape). I also installed a thrust bearing as I had one laying about (took the saw apart so I could machine a flat on what was a cast iron surface with the pattern relief angle preventing a square surface for this function), and it's really a missing part (even on my Ellis 1600 bandsaw). On that note, thrust bearings are missing on the draw bolt for the milling machine, which I added to pull the R8 collet in on my Wells-Index mill, and I made one for my antique Rockford horizontal mill (uses #9 Brown and Sharp taper). On the vertical mill, I used a knurled piece of 3" round stock, 2" long to replace the hex nut that the original had. I find I can hand tighten that and get the R8 pulled in with hand force, I do use a rubber strap wrench if needed to give a bit more torque. That thrust bearing makes all the difference. I know people will think I'm crazy as you must use some long arm wrench to tighten these draw bolts. But I've not found it to be a problem in 30 years. I used the clutch throw out bearing from my 1981 Datsun B210 for the vertical mill.
It's clear what degree of trust metric_taper places on thrust, with amount of thrust his post carries..
Bad puns aside, that mechanical aspect is so often neglected or not even considered. I've lapped hard washers to gain that security on torqued fasteners; those being repeatedly loosened need it most of all. Any burr or dirt scores mating surfaces, requiring increased tightening for retention. Easily cured with various efforts of lapping, and a bit of high pressure lube.
My long-time go to mill wrench are double box ends, 3/4" and 7/8" in the case of running a Bridgeport pattern. 3/4" does the drawbar and sometimes handy operating the vise, along with convenient parking between operations, and 7/8" for clamping hardware, another handy parking spot.
A neophyte operator watched me, next day had same wrench as I........, but lacked some discretionary finesse.

But I've never sheared a drawbar. I told him so, adding that wrench lengths are coordinated to sizes of related fasteners; not the requirement to use all of it!