TechWise
Member
- Location
- South Ayrshire, Scotland
I recently acquired a Tom Senior horizontal milling machine from a garage clearance. A previous owner took it to bits with a view to cleaning and refurbishing it. He then lost all of the bolts but assures me all of the important bits are there. The latest owner bought it in bits as a rainy day project then downsized so it had to go.
There are holes in the casting about 1/2" in size. An M12 bolt will go in about a turn then get stuck. A 1/2" UNC will go in about the same distance before binding up. A 1/2" UNF won't even start as it's clearly far too fine. I've just been and gotten some 1/2" BSW and 1/2" BSF bolts and it's not those either. There are also some holes about 3/8" in size, but again they don't seem to be M8, 3/8" UNC, 3/8" UNF, 3/8" BSW or 3/8" BSF. Oddly though, there's one pair of mounting holes that are definitely 3/8" UNC, which convinced me to try forcing UNC into one of the other holes but I had shards of metal coming out so it's definitely not all UNC. This has got me wondering if a previous owner has hit the same problem and retapped two holes he was working on only.
Are there any other oddball threads out there that might have been in use on an 1950s era British built machine before I get the impact wrench out or the mag drill and start making it all metric?
There are holes in the casting about 1/2" in size. An M12 bolt will go in about a turn then get stuck. A 1/2" UNC will go in about the same distance before binding up. A 1/2" UNF won't even start as it's clearly far too fine. I've just been and gotten some 1/2" BSW and 1/2" BSF bolts and it's not those either. There are also some holes about 3/8" in size, but again they don't seem to be M8, 3/8" UNC, 3/8" UNF, 3/8" BSW or 3/8" BSF. Oddly though, there's one pair of mounting holes that are definitely 3/8" UNC, which convinced me to try forcing UNC into one of the other holes but I had shards of metal coming out so it's definitely not all UNC. This has got me wondering if a previous owner has hit the same problem and retapped two holes he was working on only.
Are there any other oddball threads out there that might have been in use on an 1950s era British built machine before I get the impact wrench out or the mag drill and start making it all metric?