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pjwilletts
03-05-2017, 10:25 PM
I want to take a thin rope and wrap it around a metal pulpit tube to give it a more classic look....what can i use to adhear the rope to the metal and also to seal the rope against the elements?

cstevens
03-05-2017, 10:45 PM
I want to take a thin rope and wrap it around a metal pulpit tube to give it a more classic look....what can i use to adhear the rope to the metal and also to seal the rope against the elements?

I'm sure Jay or Bob will be along shortly with the correct answer based on their years of experience, but I'd vote for shellac. Works great for bicycle bar tape. I suspect that the proper nautical technique would involve Stockholm tar, Japan drier and boiled linseed oil but shellac would do the job, look great and stay put for a long time.

EDIT: Looks like this topic has been covered before, with some discussion of shellac and a report on it after a year or so:

http://forum.woodenboat.com/showthread.php?130928-Wrapped-wheel

http://forum.woodenboat.com/showthread.php?146984-Shellac-Report

Bob Cleek
03-06-2017, 10:40 PM
Yea, it's been discussed before. Get yourself a copy of Ashley's "Knots" and knock yourself out. It's on line: https://archive.org/details/TheAshleyBookOfKnots

Nothing is used to make the line adhere to the stanchion. It's knotted. The knots keep it on.

Shellac is a good sealer for fancywork indoors, or if you want to renew it regularly, outdoors. It will build up over time, though, dries out and will crack after long UV exposure. It's easily thinned and can be soaked off with alcohol.

A soaking in thin shellac, which will soak into the cordage easily, covered by paint holds up the best.

It's not rocket science, but you will probably be surprised by how much line it takes to cover stanchions.

Sad to say, like a lot of things, decent, clean, uniform, hard-laid three strand cotton "cod line" or "seine twine" (Sometimes also called "Belfast Cord") is very hard to find these days. I don't know if it's even being made anywhere now. It certainly doesn't seem to be available on line from anybody. The serious knot tiers I know seem to be using "new old stock," and jealously guarding their "stashes." What we are talking about is a tightly laid pure long-strand cotton cord with a stiff, hard "hand." It has to be "clean" without lumps and crud in it, so that the diameter is uniform throughout. Trying to tie fancy knots with limp, soft-laid line is difficult. Today, it all seems to be synthetic material, which often doesn't hold a knot well because it's prone to slipping. (It's also harder on the hands to work than cotton.)

The closest I've seen available on line is Phoenix's "cotton cable cord." It's a polyester blend, which they say makes it harder, but it's used for chalk line, so it's probably not laid that hard. (Chalk line is soft so the chalk will hold to the line better.) http://phoenixrope.com/rope-products/natural-rope/cotton-cable-cord/

http://phoenixrope.com/wp-content/uploads/2013/09/cotton-cable-cord-3-sizes.jpg

Maybe one of the marlinspike sailors in here will be along and give you some tips on where they get their line these days. Vince Brennan is your man for that.

babaluey
03-07-2017, 04:01 PM
We served (wrapped) all our dyneema rigging with black marline on top of a layer of friction tape parceling. Just plain old electricians cloth friction tape. Under the pressure of the winding marline it becomes almost putty-like and makes a nice grippy foundation. I think it would work well on metal tubing too, but if you're serving with white cord there might be some black from the tape showing through. You'd need to experiment to see how it looks. Black marline is already coated in stockholm tar so requires no finish, but you can renew it every one or two years by smearing with a sludge of stockholm, linseed oil and varnish.