What is used in this situation, inorder to spread load and avoid any galvanic activity. Some of my fixtures will be cast and others ss.
Ahoy Stewart, there doesn’t seem to be enough information here , maybe you could take a deep breath, and focus our attention on a particular area, of your concern ?
Douglas
Sorry folks,The whisker stays, boomkin stay tangs, chainplates and such are bolted thru the fibre glass of the hull. They would have a nut and washer in place, I wondered whether there was a metal plate in addition to this which would spread the load over a greater surface area to prevent crazing of the fibre glass. Is there a flexible “gasket” type of material used for cushioning or bedding effect for example underneath the plate.
Hi Stewart, My BCC is an older one, being commissioned in 1985.
The Morse Co., used square ss washers under the ss nuts. these were about the same size across as of what we know as fender washers,in diameter, but these washer-plates were thicker.
The midship chainplates were bolted on with these “square-plate” washers, too.
Do you see crazing on the gelcoat around the bolts or tangs on your chainplates ?
Recently, I read on the Brion Toss Riggers Forum, that some boats were successfully assembled using butyl rubber tape, instead of using a calk type beding compound, but I would still use 3M5200 on and around each bolt shank, too.
I found butyl rubber tape listed in McMaster-Carr catalog.
Douglas, BCC # 072
For this job Butly rubber is preferable over 5200
The butyl rubber is a flexixble compound, designed to expand or contract depending on the load exerted upon it. It is the same product that is used to seal the hull to deck joint on many boats, including the C&C range through the 1970’s and 80’s.
5200 is a definative sealant, and whilst it may have some elasticity, it does not have the ability to revert back to shape as butyl rubber does.
For this job Butly rubber is preferable over 5200
The butyl rubber is a flexixble compound, designed to expand or contract depending on the load exerted upon it. It is the same product that is used to seal the hull to deck joint on many boats, including the C&C range through the 1970’s and 80’s.
5200 is a definative sealant, and whilst it may have some elasticity, it does not have the ability to revert back to shape as butyl rubber does.
thank you everyone, I have a fair bit to learn yet however the boat and parts are starting to come together, it is quite exciting.
Hi Doug, mine is a new construction project and I am tring to fit such that I don’t get crazing in the gelcoat. Hopefully I can succeed!
Stewart,
have you ordered rigging? Drop me your email.
ben ATT beneriksen DOTT com
wheres the pics of the progress?
Are you in Maine?
-B
Hi Stewart, my 1985 BCC, didn’t have any gelcoat crazing around any hull structural fittings.
I can understand your concern, though.
I guess my only recomendation would be to have slightly larger bolt holes through the f/g hull, so the bolts could draw tight, straight, even if the drilled hole had a slight angle.
The hardest chainplate hole to drill is the upper midship ones, that go through the rub rails.
I think the Morse yard , originally drilled these upper holes, one half way in from outside and half way in from the inside, then “wallow” drilled the meeting place into a near alignment.
The ss 3/8" bolts that I extracted from these upper holes, were bent in the middle, as it they bent during driving them into place.
Most everything I have read about fastening plastic with metal fasteners, says to allow the plastic room to move a little bit around the metal fastener.
I also think it would be important for you to have your chainplates bent to a curve that matches your hull curve, my factory ss ones, were not, and they slightly distorted the f/g hull when the bolts were drawn up tight.
Hope this helps, Douglas