68865Re: [bolger] Pegleg Mast
- Sep 29, 2012I am setting here thinking through my probably flawed logic. It has
always been my understanding that solid mast is not as strong as a
larger one that is hollow. The thing being that they both weigh the
same. Mr. Bolger told me that the mast compliments the lift on the sail
by improving the shape of the sails leading edge. This may be true If
you are using his figure eight lacing that allows the sail to revolve
around the mast. So up to a point maybe the bigger diameter mast might
be more efficient??? Epoxy and glass on the outside may well strengthen
the mast if the weather is cool?? Epoxy softens in heat so I would not
varnish the mast I would paint it white to reflect sunlight at least in
the area of the splice. I built a mast for a 35 ft sail boat about 40
years ago. It was rectangular in shape and I built it hollow from bottom
to top with drip proof vents at the top and hollow all the way to the
bottom so that air would be able to circulate up through it. I saw the
boat a few years ago and she had been through several owners but still
carried the same mast. I believe that fiberglassing a wooden mast is a
mistake. I think a slightly larger mast that weighs the same as the
fiberglassed one is stronger. All this is mostly my thinking and I am
posting it only as speculation and food for thought. Doug
On 09/29/2012 04:03 AM, Mark Albanese wrote:
> Thanks for the encouragement, John. With so many steps I had to do it in
> 6 ounce dribs and drabs, so it took awhile to get this far. Still, much
> easier than building another one. And Rick did some very nice work worth
> saving. Light it is. Except for this flaw, solid. Nice fittings. I love
> its beautiful built in curve.
> Here's how things looked after the accident. There is birdsmouth fairing
> around the outside of the lower plug. See how the glass was snapped cleanly?
> The original crack between the strakes is just above this break and must
> have been a quarter inch wide and six inches long before It stabilized
> with the T88. No new damage there.
> I cleaned up the shards, filled flush with a silica and epoxy, then
> drilled stepped holes for a foot long piece of 3/4" zinc plated
> all-thread. I'd thought 12" just right, long enough to reach into the
> thick part of the foot, spanning the joint strongly, and not going so
> far up as to create a perfect spot to snap just above the partners. Not
> to mention 6" either way was about all I thought to get reliably straight.
> The original idea was to create nice threads in both the upper and lower
> sections and then screw them together, mating the faces carefully with
> thick epoxy. I vaselined the metal in this first try, but hey it was
> stuck for good. In the end I just stuffed as much not too thick and not
> too thin epoxy down the hole as possible and stuck 'em together. Just
> enough oozed out to make a good join.
> Here, ready for glassing.
> Just today I put the third coat on three layers of 12 oz. biaxial tape,
> two at 45 45 straight round the joint, one spiral in between.
> It's the first time I've used this and like it rather more than the
> selvage edge material. The edges will need less grinding off and they
> don't unravel nearly as much as plain fabric. It doesn't go as clear as
> looser fabric. No matter; maybe add a bright white racing stripe.
> This photo is of the drying second coat. At half 85 degrees; half 50
> over night ( ah, Portland late summer), it needs some cleaning up on
> Sunday morning and waiting till late next week for the Raka to mostly
> Then it's off to give it a try with anemometer in hand. Whoopee!
>> On Sep 28, 2012, at 10:56 PM, John Kohnen wrote:
>>> "Dime?" "Nickel?" I guess the tale is growing with the telling. ;o)
>>> Most of the stress on a mast is handled by the material near the
>>> of the mast. Your all-thread solution is a good one for holding the two
>>> parts of Sage's mast together and in line, Mark, but put plenty of
>>> on the outside of the mast to carry the load. And make sure you've
>>> all the varnish away before you do it. <g>
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