I've just joined and have a specific question, that I hope you can help with;
I'm up-issuing a drawing at present, relating to a machined block with a machined bolt going through it.
The bolt has an M12 Thread on it, but there is no indication of what pitch the threads are (I don't know much about that anyway). I don't have any thread gauges available, only a vernier caliper.
On the existing 'assembly drawing', there is a note which states:- Screw bolt in to block face, hand tight only. Then back off 1/4 turn.
Then drill a 1/8" hole on the center line (of the bolt), completely through the assembly.
The threaded end protrudes through the other side of the block, and a cap nut is fitted to it, with the same instructions as above.
The 2x 1/8" holes are then pinned with slotted roll pins.
The crux of my query is;
How can I determine the bolt length, and the positioning of the 2x holes on the bolt? (1 on the shank near the bolt head, and the other through the threaded end).
I want to add reference dimensions for the benefit of the machinist who will manufacture these items.
How do I work out what distance the head of the bolt is from the face of the block?, after turning it back a 1/4 turn, from being hand tight against the face of the block?
I can only guess at this at present, but there should to be a way to work it out, should there not?
I would appreciate any help, that any of you can provide.
Thanks & regards,
And you think the print is unclear?