A friend for whom I have done repairs on spinning wheels brought me a loom she had got from India made of teak. The problem was that it would not lock adequately into the upright position. I examined the loom and determined that the slotted machine screws just spun as the wingnuts were tightened.
The loom was actually quite well made, except for the white plastic parts, but they just couldn’t or didn’t figure out all of the details. So I decided that two of the four machine screws in question could be replaced with simple carriage bolts. I used a square file to make the bolt go into the hole without splitting the wood, and that worked out fine.
However the other two machine screws could not be replaced with ordinary carriage bolts, so I had master blacksmith Mark Schramm weld on tabs on both sides of the square top of the carriage bolts. I had to remove one of the shed spacers in order to remove the old screws and insert the new tabbed carriage bolts.
Once they were in place I repositioned the spacers in the proper location, put it back together and low and behold it works. And the happy customer brought me this hand spun dishtowel that she had made on the loom. Thank you.