Gaffer Mast Chafe

[Jack G]

Well, after only two sails my 12' catboat's mast is bare where the
gaff jaws ride on the mast. The design did not call for anything beyond the wood of the gaff and jaws, and no riding shoe. I'm reluctant to cover the mast at the bearing area out of fear of trapping water. Mast is 3-1/2" Dia. Everything is painted with two coats of primer and high quality topside enamel. Has anybody used copper?

[cs]

What about wrapping the gaff jaws with leather?

Chad

[WindHawk]

That seems to be a good idea Chad. Make 'em thick (or doubled), and replace as necessary.

I'm currently trying to get my wife to make a set of 4" x 4" leather chaff guards for where the trailer straps go over the combing & gunwalls. She insists that I need to learn to sew heavy material, as that's a traditional sailing skill... :rolleyes:

[Andrew Craig-Bennett]

My boat is 37ft and 12 tons. The gaff jaws are bare wood, but the tumbler is slathered in tallow, and the mast in way of the jaws in the full hoist position has vertical strips of oak, tapered at the lower ends, about half an inch square, screwed to it. Works perfectly. Has done for fifty years or more.

[Ian McColgin]

I've set in teak strips as ACB described his oak. Works well and looks fine.

You'll want to leather the jaws and if you've not got one, what ACB calls the tumbler, a pivoting up and down piece about 3x longer than the jaws are thick and set between the jaws to spread the compression load, should also be leathered and tallowed.

I do not recommend copper or any other sheeting for just the reason you noted. Mya broke her foremast a few years ago on a winter sail and the cause was rot under the copper, probably water getting in through the tacks.

G'luck

[Bob Smalser]

I've been installing leather as chafe guards and pads.

http://pic3.picturetrail.com/VOL12/1104763/3075025/59303995.jpg

Vegetable-tanned tooling cowhide...it stretches when wet and shrinks nicely when it dries. It also ages beautifully. And you can get it in thick weights.

I scruff the area to take the leather with Scotchbrite to make a bond for the poly sealant (5200 equivalent), coat the area with poly, stretch the wet leather where I want it and tack it down with brass or copper box tacks. Cleanup with mineral spirit-dampened paper towels. Oil the leather after the poly cures. I use a neatsfoot-beeswax-pine tar mix.

The poly cures under the wet leather adequately and provides a good seal for the tacks.

Make patterns out of graph paper and cut the leather undersize to allow for the stretch.

http://pic3.picturetrail.com/VOL12/1104763/3075025/59303981.jpg

I buy the leather in quarter hides off of Ebay for 40-50 bucks and the supply lasts me several years to make straps, guards, spreader boots and such. Tandy Leather also sells it for more money.

For a fiberglass-hard surface, you can also use rawhide. Stretches and shrinks more...and doesn't take oil well....but practically bulletproof.

http://pic3.picturetrail.com/VOL12/1104763/3075025/59306398.jpg

http://pic3.picturetrail.com/VOL12/1104763/3075025/59030331.jpg

[ 07-08-2004, 11:28 AM: Message edited by: Bob Smalser ]

[Andrew Craig-Bennett]

Good point about poly. under leather. I should have thought of that.

[Ian McColgin]

Nice work Bob.

One trick I've used on inside curves such as gaff jaws or the notch in a boom gallows - a variation with more gap works on outside curves - is to cut the part that folds to each side of the piece and will take tacks into a series of UUUUUUUU. The radiating pattern is quite attractive and it gets the leather around difficult shapes with minimal fuss.

Leather is hard to make work on the mast where the throat lands as there's always that little bump that will try to curl up more each time as you hoist. Very modestly inlaid strips - I just notch them in about 1/32 - that taper on the bottom (and top if you're feeling decorative and symetrical) to exactly the mast surface are very nice.

If you use wood strips, have the space between them small enough that the tumbler (I like that term, never used it before, hope I'm using it right, thank you ACB) spans the full breadth of two strips and the intervening gap and thus will not bind in the slot.

I like using seven strips across a 120 degree arc as this makes mystical and numerological sense.

[Jonathan Kabak]

Here's my two cents for what it's worth....

As said before you want to leather the jaws as well as the coin, tongue, clapper (take your favorite term) with a fairly heavy grade of leather. Tooling leather or heavier would serve best. Make sure you paint and or varnish under the leather first. Don't go crazy with adhesive as you should be able to pull the leather off to inspect every year or so. Likewise treat the leather with neats foot oil and then mink oil or similar dressing.

As for the mast..with such a small diameter you really can't go with barrel staves of oak as you do on a larger diameter mast. Go with sheet copper and make sure you bed it well. I would use either roofing tar or dolphinite. Again the idea is semi-permenant installation, something that you can remove every couple of years to take a peek at. The other option would be fiberglass cloth at that section. Not as traditional but wouldn't look to bad either.

Just my professional opinion

Jonathan

[Smacksman]

Stuff on the mast works till you reef.

I would go for leathering the jaws and tumbler and treat with neatsfoot oil to keep it supple. Tallow stinks after it's 'sell by date'. Varnish or paint the mast after laying up so it has all winter to harden up then the oiled leather seems to slide ok. Never use silicone - it slides ok but you will never get paint to stick thereafter.

Check your jaws are not too snug round the mast so that when the gaff rotates axially, as it will off the wind, it doesn't bind on the mast.

[John B]

Nice to see you back on forum Smacksman. I picked up somewhere you've been on an ocean journey? That would warrant a post over in Misc boat related. hint.

mast chafe. I do both. leather... vaseline and some mast protection. thats why she has 3 bands on the mast. just remember this phrase if you're thinking about copper and tacks.

" tear along dotted line"

[Jon Etheredge]

Leather on the gaff jaws and the tumbler will work. I stitch the leather in place on the jaws to eliminate concerns about tacks or nails causing a break but I don't worry about tacks in the tumbler. Barge cement (available from a shoe repair shop) is a leather adhesive that you can use in addition to the stiching that is a lot less messy than 3M 5200.

Here is a photo of the boom jaws and tumbler on my 13' catboat. The gaff jaws and tumbler are done the same way. The leather is continuous on the inner face. What look like gaps are just "darts" in the leather to allow it to follow the curve of the jaws:

<center>
http://www.imagestation.com/picture/sraid91/pb26e4e047231297bf10610fac13f1525/fa5f87d5.jpg
</center>

[ 07-12-2004, 09:47 PM: Message edited by: Jon Etheredge ]

[Nicholas Carey]

By all means leather the gaff jaws and tumbler.

Similar to ACB/Ian McG's vertical [hard] wooden chafing strips, you can also install brass half oval.

You'll want to install them in 2 or 3 place: where the gaff jaws ride without a reef in, plus a set where the gaff jaws ride when reefed.

Also, check how the tumbler sits when the sail is hoisted. I've seen some gaffers where, unless you were really careful making sail, the tumbler would get cattywampus (e.g., not parallel to the mast) and chafe the mast on its own. I suspect that this particular habit has to do with either the parrel being too loose, or the tumbler not being long enough.

[Nicholas Carey]

Originally posted by Jonathan Kabak:
[when leathering]&hellip;Don't go crazy with adhesive as you should be able to pull the leather off to inspect every year or so.Actually a good adhesive to use for bedding leather chafing gear is good ol'l rubber cement. Easy to remove. Doesn't trash the varnish underneath when you remove it. Cleanup is easy.

For greasing leather, it's also hard to beat Huberd's Shoe Grease. Made from beeswax and pine tar in in McMinnville, Oregon, It's pretty much unimproved since 1929: thousands of PNW loggers can't be all wrong.

https://secure.armysurplusforless.com/images/upload/huberdssnogreaseM.jpg (https://secure.armysurplusforless.com/productInfo.cfm?prodID=3277&colorID=1296)

You should be able to find it at any decent workboot dealer or tack shop.

For really serious leather greasing, melt it in an improvised double boiler and paint it on with a chip brush.

[A little googling reveals, somewhat disturbingly, that Huberd's appears to be the Leather Dressing of Choice for the S+M/BDSM fetish types :eek: &mdash; people who, err, know their leather, so to speak. :D ]

[Smacksman]

Shoe grease. I wonder if that is what we call dubbin this side of the pond? Good stuff.

Hi JohnB, yes it's great to be back after 5+ months and 5,000+ miles in a 6 foot fo'csle.

Most people think it's no big deal ocean crossing nowadays so I wasn't going to mention it other than some info on the twizzle rig we used to great effect which might be useful to others.

Twizzle rig site at -
http://www.simetric.co.uk/twizzle_rig/

[ 08-06-2004, 08:08 PM: Message edited by: Smacksman ]

[Ian McColgin]

Please Please Please tell us about the crossing and especially I'm interested in the twizzel. I believe I was the first, before you the only, to mention this. I've only experimented and improvised to see if I'd want to do this for real. I'm sure I do before heading off shore, but any remarks and photos would be hugely appreciated.

[PeterSibley]

Smacksman...please do.

And I'll put in a plug for any of the lanolin products....Lanocote being my favourite.I don't kow if they're available in Britain or the USA , but they're definitely the best thing ever for softening hard leather.

I recently scrounged some very useful sized pieces of 1/4" thick leather from a failed upholstery workshop.It had sat in the rain for some time and was not only hard as the proverbial board but resistant to all softening efforts ...including soaking in water for a week or so.The only thing that worked was the Lanocote.It made the stuff quite flexilbe and useful.No, I don't have shares .Wish I did smile.gif

[ 07-13-2004, 07:12 AM: Message edited by: PeterSibley ]

[Smacksman]

I would definitly go for the twizzle rig Ian. We started off low tech and ended up zero tech with the best downhill cruising rig I've used. Zero chafe, reef from the cockpit, kills the death roll and will trim to 60 deg. either side of astern.

I've got a lot to catch up on but I plan to make a web page and a DVD on the subject. But I'll put a bit on the Misc. Boat page here asap.

Oops! I put the link to twizzle info above in stead of here -
http://www.simetric.co.uk/twizzle_rig/

[ 08-06-2004, 08:13 PM: Message edited by: Smacksman ]