Re-furbishing Lofrans Royale Windlass - 2

[ghostlymoron]

Further to my previous post, I also need to drill and tap some 8mm threads in the body of the windlass. The holes are at the moment 6mm - one has a broken bolt in it. The Lofrans parts list however shows these as 8mm. I've no experience of tapping a thread - it can't be that difficult? What size blank hole do I need for an 8mm bolt? Drill size?
Thanks all

 

[TQA]

There are slightly different requirements for fine medium or coarse thread bolts. In an ALI casing it would be usual practice to use medium or coarse threads. Use grease or oil as a lubricant.

SEE http://en.wikipedia.org/wiki/Tap_and_die


Tapping is not difficult but I am not sure that I would want to use a hard to replace casing for my first attempt.

 

[robertj]

6.8mm