Bedding compound

T

tbennett

New Member
Joined
8 Aug 2006
Messages
21
Visit site
I'm having to replace some mahogany quadrant beading on the deck/coach roof junction which was previously inadequately bedded (hence the leaks) in some black rubbery stuff which despite leaking made the beading very difficult to remove. What do people recommend I use as a bedding compound for the replacement to avoid the same problems?

I have read about using non-setting builders' mastic, when I went to Travis Perkins they recommended 'oil based mastic' a brown oily goo, is that it? Tradboats also sell a bedding compound which they say stays soft, perhaps that is the thing to go for?

By the way, I posted earlier about sourcing mahogany quadrant bead - Robbins in Bristol were very helpful and are machining it up for me.

Thanks...
 
Linseed oil putty, thinish stuff, is what I use for bedding cleats etc. I reckon trad boat would know the right stuff, builders mastic would be OK as well, as long as you dont use too much.
 
i used bitumen (used for roofing) from builders merchant for bedding decks.

used oil based mastic (for windows) for bedding the sealing/frames around the windows(mahogany to mahogany)


happy to report no leaks yet!

steve.
 
Builder's mastic; be very sure to paint both faying surfaces with two coats of primer. If you don't do this the oil in the mastic migrates into the wood and it dries out and is useless.

Alternatively, for a really good job, use white lead paste - I've known this to be still soft after 48 years. Again, prime both faces two coats first or its a waste of time (and, in this case, money!)

DON'T use Sikaflex, etc., for these jobs! The beading will have to be chiseled out if there is a leak - and quite often there will be!

Old boatbuilder's trick for stopping leaks - take a grease gun and fill it with white lead paste mixed with a bit of grease. Drill a hole through the middle of a coach screw and braze a tecalemit nipple onto the head.

Drill small hole in the offending coaming, deadwood, whatever, wind in the coach screw, hook up the grease gun and pump in white lead paste until you see it coming out somewhere... repeat further along as required.

This is a brilliant trick and I have never known it to fail...
 
Sorry guys,have to disagree! For bedding of almost anything, its hard to beat Butyl rubber (Arbomast BR). I have removed fittings 18 years later and this stuff is still gooey. Oil based mastics go hard eventually, just like putty and paste, especially on timber/timber joints. I agree if you prime the surfaces it lasts longer though. White lead paste goes hard too, unless mixed with grease, linseed or other secret ingredient.....if you have the time.
Save Sikaflex and polyurethene sealents for deck seams, and silicone sealants for your bathroom.
You can get Arbomast BR in grey or brown from Marine and Industrial sealants, Norfolk. For an easy clean-up tip, spray the fitting with white spirit before removing excess mastic with a piece of timber sharpened to a chisel point. Magic !
 
Oh yes, the hollow screw to grease nipple trick works well with Butyl rubber too, but it needs slight thining with with sprit to make it pump through the gun in cold weather. Great for cabin corner posts ......
 
Thanks for that, I'll get some of that, where in Norfolk are they? As I work offshore Great Yarmouth at present.
 
Thanks Forbsie!
How would you like another visit?? Myself and Sainty and John Beddoes!!!! Plus Belinda! You up for losing yer teeth again? Be around my birthday time!
 
You must log in or register to reply here.

Share this page

Top