Refastening

[BuccaneerCapn]

What is the purpose of counter-sinking plank fasteners?

[ssor]

That's easy!
A: you don't want them to stand proud.
B: the countersink allows filling and sealing the hole.

"A" help to make the hull "fair", "B" helps to keep the water on the outside.

[ssor]

On this thread I have a question ; Has anyone dipped the screws in plumbers pipe dope before driving them? It does such an effective job of sealing pipe threads that I wonder if it would be beneficial on boat planking.

[ 04-08-2005, 08:56 AM: Message edited by: ssor ]

[BuccaneerCapn]

One reason I asked is since I am planning on copper sheathing the bottom, the heads will never again be visible, and I would think the tightness of the screw going in would seal better that the bung over it. Just a thought process.

[ssor]

Fasten several short boards to a plank with screws, give it a long soak, dry it for a day or two and pull the screws and see if the holes are dry. Rip them through the center with a band saw. If you use screws that are not plated and add a handful of salt to the soak water you may learn all sorts of things.

[sdowney717]

IMO,
Builders thought it would keep the screws from corroding, it does not. Although, it does slow down the amount of water getting to the screws and may slighly prolong their life.
It may help slow down any leaks from poor fitting shanks and screw heads.
Its always been done that way.
I dont see fairness as much of an issue except for looks.

[Bob Smalser]

If done neatly, countersinking and plugging keeps the screw slot clean so it's easily removed later. Just pop out the plug with a chisel.

[BrianW]

Speaking of chisels Bob...

When I get my boat hauled what kind of chisel works best for knocking out the bungs? Any other advice for getting to the screws? Guess I should have an assortment of screwdrivers handy. smile.gif

[Concordia..41]

Pop out the bungs with a chisel?

Shaving off the tops of the new bungs yes, but the other is a new trick for me.

The forstner bit was just the ticket for the 100+ bungs I removed yesterday.

From long ago and far away...

Removing Bungs (http://www.sailingwithsarah.com/proj6.html)

[BrianW]

Concordia..41,

Thanks for the link to your website. I spent some time checking out a few of the pages and learned a couple things that will help.

[BrianW]

Oh, meant to ask a question.

Would it be a good idea to to pick up some of those forstner bits and appropriately sized bungs. Seems like it would speed things up a bit since I don't have much time once she's hauled.

[Bob Smalser]

If the plug is installed with just a dab of varnish or paint around the edge so as to keep the slot clean, then the corner of a common butt chisel can be dug in just inside of the edge of the plug and with the chisel bevel resting on the surrounding wood surface, the plug can be popped out, often in one piece.

If the plug was slathered with too much paint or anything stronger then more drastic measures may be called for.

[ssor]

Sometimes just driving a drywall screw into the center of a bung will pull it out. other times, when they were put in they weren't intended to ever come out.
Were you using a forstner bit a little smaller than the bung?