How close do clevis pins need to fit?

[steve77]

We are an american boat, with everything sized in inches. We are currently having the mast and standing rigging replaced in Lisbon, and I am having a problem matching a metric mast to my imperial chainplates and other equipment.

Sparcraft keeps telling me not to worry about it, and that they will match everything up. Color me skeptical, because it looks to me like they plan on using 12mm pins for the mast tangs to fit 12.7mm holes in the Hi-Mod terminals. For the cap shrouds, it is a larger mismatch - 16 mm pin in an 18 mm hole.

So, how close does the match between clevis pin size and the hole in an eye terminal need to be?

Thanks!

Steve

[Rustic Charm]

I would have thought 2mm would not be ideal. I replaced my chain plates last year but they were made to fit the pins so the gap is almost nil. It's a very neat fit.

[GordMay]

Clevis pins should completely fill* the hole into which they are inserted; to limit wear and reduce the failure rate of either the pin or the clevis.

* Within about 0.025mm (25 microns, or 1/4mm)

[steve77]

Thanks, Gord. Appreciate the info.

I was always under the impression that it should be a very close fit to avoid point loading. I just don't know how close, and I certainly don't have a reference.

I have been looking for a standard of some type - ANSI, ASME, ABYC... Do you have access to something that I could look at?

Cheers!

Steve

[deblen]

A handy MM to Inch Chart :

https://www.dropbox.com/s/s0diw6xidq...c-SAE.pdf?dl=0

[steve77]

Originally Posted by deblen

A handy MM to Inch Chart :

https://www.dropbox.com/s/s0diw6xidq...c-SAE.pdf?dl=0

Thanks! The dimensions of US coins is especially helpful. I knew most of the common conversions from memory, but the coin sizes will help visualize it better.

Appreciate it!

Steve