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Lazy Jack
04-13-2001, 09:18 PM
How is the gunter usually affixed to the mast? I built a tapered mast, 2 7/8 to 1 1/2 over 10 feet. The gunter is a straight 1 1/2 diameter. The sail will be lashed to the gunter and have hoops around the mast. The halyard will attach to the 8 foot gunter and run through a sheave in the top of the mast such that there will be two feet of overlap ( six feet of gunter above the top of the mast) How is the foot of the gunter controlled, Jaws and parrel beads? How do you take up the slop in the jaws as the gunter is run up the tapered mast?

barend
04-14-2001, 05:55 AM
Correct, jaws with beads. Thats all. Pressuire keeps the jaws against the mast. Barend

Stephen
04-14-2001, 08:25 AM
When I built my Gunter rig on a similiar sized craft, I found my parrel beads at the local bead craft-shop. They have lots of variety and sizes.

Buddy Sharpton
04-14-2001, 09:32 AM
I'm a little skeptical of just a two foot overlap on your spars. I have a Cape Dory 14 "whitehall" with a gunter rig. Its very convenient to set up with no stays to rig and easy to stow and tow with every thing riding in the boat. I felt for my light airs I could use more sail so I built a new sail with about 16" more height, and another set of reef points. The boat already had a set of reef points and the way you reefed was to retie the halyard to another pad eye on the spar 2 feet higher and hoist so the whole rig is 2 feet lower.Works great. So I put another padeye on the spar just 12" lower to raise the new sail 12" higher( with the boom 6" lower) and discovered that the weight balance shifted so much with that foot less spar below and foot more above, a 24" difference taht when you lower the spar the head wants so come down faster than the foot wants to slide down and it jams until you go forward and pull down on the luff of the sail as you easy out the halyard. Its an inconvenience and could be dangerous to a novice surprised by a squall and struggling to get the rig down.I think your overlap of just two feet on a ten foot spar will do the same but worse. You could weight the lower end but that's working way against your righting moment. I would imagine an overlap of 42" to 48" or so would be a vast improvement. Surely you could experiment easily enough with a dummy spar roughed out of scrap to check it out before you spent time building a nice one.

Lazy Jack
04-14-2001, 10:22 AM
Thanks for the replies!!
Buddy
I have come to some of the same conclusions about the short overlap. I have not cut the gunter to length yet so I plan to leave it long (currently nine feet) The gunter is a nine foot length of closet rod of spruce or fir which I have wrapped with fiberglass tape and epoxy to give it a bit more stiffness. I may still have trouble with there being too much length above the halyard.

Is there anything on your rig, Buddy, that retains the gunter against the top of your mast , ie. a V or half round channel or something or is it simply the tention of the halyard? Better said, once the gunter is hoisted into position, what is there to keep it from wracking and twisting side to side?

I have thought of using some v blocks of hardwood fixed to the mast at each end of the overlap. The halyard run through a sheave in the mast between them would draw the gunter in tight to the V blocks and keep the gunter from swinging out of line with the mast.

But I fear that I am trying to re invent the wheel and may be overcomplicating a simple sysem!! Is the amount of wrack with nothing but jaws and a halyard simply not enought to worry about?

If you could describe your rig in more detail it would help me out tremendously!
Thanks

Buddy Sharpton
04-17-2001, 09:32 PM
Dear Jack, I have had about 16 year's experience with my Cape Dory 14, the whitehall, not the wider beamed catboat they also used to make. I have tried various improvements to snug up that rig and here's what works, and what didn't. The mast comes witha cast aluminum head that has in addition to the sheave for the halyard, two fingers projecting aft forming a u shaped pocket (socket?) for the spar to snug into, Mast is 2" ,spar 1 1/2" tube. Its a tolerable, not snug fit. Thinking I would improve on this< I made a dandy mahogany piece to do the same pocket/socket deal on the heel of the spar to lock the two parallel to each other. Painted the overlapping portions white on buff spars, looked like a topmast setup on a bigger boatand you could imagine crosstrees. I thought the hole mast would then swivel with wind pressure to align with breeze. NOT! What I created was a rig that stayed fore and af, t when paying off spoiled the leading edge of sail with the increased mast shadow/ turbulance. Far better to let the spar twist of at jaws, because the upper spar would never stay snug in upper pocket because you can't keep halyard tight with no stays to pull against aft so it always creeps a little and the spar escapes the socket, the whole spar at head and jaws can rotate in line with wind, the body of the sail pivots similarly on the mast hoops and you get a much better setting sail . I would forgo the masthead fingers entirely and if you look, you won't find any wooden boat mast plans for a gunter rig showing them. Just let that line wear at the masthead sheave, cut off 6" every 300 hours of sailing so it won't surprise you and pop. Buy that halyard another 2 feet longer and you're set for life for $.78 extra. I do have a twaeker that I do like. The halyard is led through a bullseye fairlead on the stem and aft two feet along the gunnel to the cleat. I've got another 1/4" line which goes from a eyestrap placed below this run of halyard, over the halyard, and back down thru the fairlead of a clam cleat tbeside the eyestrap.
After setting up the halyard "snug", I can depress this two foot run downward with one hand while taking up the new slack on tha 1/4" tweaker" and get a real tight set ( which will adjust to that 1 1/2" away from the mast head set. Mind you the line at the cleat is not slipping, the halyard is stretching a little, and the geometry of the rig moving under mast bend to wind load. And the creep is GVOOD. Don't fight it. Go with the flow! Buddy

Lazy Jack
04-21-2001, 05:46 PM
Buddy
This was just the sage advise borne of experience I was looking for! I was thinking of many of the tweeks that you had described and you've already done the learnin' for me. Thanks for saving me so much work!
Lazy Jack

ishmael
04-22-2001, 02:57 PM
A source for ready made jaws and parrel beads would be the US supplier for the Drascombe line. I don't have the address, but it's readily available with a search engine.

I'm not sure about all the fussing. Keeping the gaff tight to the mast, as dictated by the cut of the sail, would seem important, but more important is probably setting as well as you can, and not worrying too much. Ya don't,usually, put a gunter rig on a boat you want to go as fast as possible. No excuse for not playing with it, getting the most out of the rig; while getting it on the water.

dadadata
05-21-2001, 10:20 AM
Not real traditional, but how about "gunter iron tubes" made of PVC pipe or Carlon conduit? I've been interested in trying PVC pipe for some time and actually have the "iron/gunter" made up.

My Cheap Pages have some drawings of the many attempts at gunter rigs from way back in the heyday of canoeing...