MAST HOOPS

[steadybrook]

What is the proper diameter,thickness and width[in relation to the mast] of mast/sail hoops??

[Buddy]

For catboats and the like(not 80ft schooner) the rule of thumb is just that, about a thumb's width between the hoop and the mast. Too tight will bind going up and down. Too loose will be pointless and start hanging up on boom and gaff jaws.

[RichardBlake]

On our 35-foot gaff cutter the right clearance would be around a thumb all the way round - but set up your main first, well stretched, and measure the distance of luff from mast. Friend forgot to do this, bought hoops allowing for good clearance, slid them on, rigged and stepped mast, and only then realised they were too big and couldn't stop the luff sagging away! Had to cut, scarf and re-rivet them in place.
All the best,
Richard

[Mr.O]

See Wooden Boat # 65 P40.

[Wooden Boat Fittings]

.
It's normally considered that the inside diameter should be about 20% larger than the largest mast diameter (ie the largest diameter of the mast if its cross-section isn't circular.)

Anything much smaller risks binding on the mast as you raise or lower the sail (especially the latter unless you use a downhaul.)

The comments above regarding catboats are interesting, and probably explain why many catboat sailors resort to greasing their masts, or spraying them with silicon, or some such. (See here (http://www.everythingboats.com/catboat/forum/bbs.pl?read=2807), for example.)

Mike

[John B]

It's a knuckle clearance here. About a thumb in other words.

[Doug B]

Around here catboat mast hoops are usually 25% larger than the mast.