Bedding between planks.

[Gary Lee]

I am ready to fasten my second lap to the first lap of my new hull. What is the choice of bedding between the planks?

[mmd]

May I answer in the form of an anecdote?

A couple of years ago I was introducing a client, who was looking for a dinghy for his new yacht, to my boatbuildin' buddy, Whammy. The client asked Whammy what he used to get a watertight seal between the planks of his lapstrake dinghies. Whammy, who doesn't waste too many words, looked him straight in the eye and said:

"Good joinery."

[Gary Lee]

There has been a lot of conversation concerning the Simmons, that discussed the water being pushed up between the planking of the older models that were built by the original designer with no bedding or caulking at all. Would it be better to use a shiplap seam?

[TimothyB]

Quick and dirty could be a thin strip of butyl rubber. You can get it sticky-fied on both sides so it stays in place while you join up the second strake. Just make sure the strip ends are also well sealed.

Here is a list of the properties of it:


Key Properties

Key Properties of butyl rubber include:
· Air tight and gas impermeable, (a unique property of butyl rubbers)
· Flexibility
· Good weathering resistance
· Resistant to ozone
· Good vibration damper
· Biocompatible If you paint inside and out it should last pretty much as long as the boat. If not, depending on use, maybe you'll have to replace some of it a few years down the road.

They even make SCUBA Dry Suits out of this stuff, it is so watertight.

Of course, the -best- way is good joinery ;)

--T

PS: Hey! I found a source for it. Its awfully cheap!

http://www.pplmotorhomes.com/parts/caulks-sealants/484 63.htm (http://www.pplmotorhomes.com/parts/caulks-sealants/48463.htm)

..and even cheaper, and a brand name:

http://www.campingworld.com/browse/skus/index.cfm?skunum=7547&affiliateID=577&siteID=nGt.Iox5rjI-SwYfwYaNjNMgsdaQAooEmQ

[ 01-03-2005, 02:29 PM: Message edited by: TimothyB ]