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ford
07-12-2000, 06:31 AM
is there any way to remove old clenched nails to facilitate re-nailing.

John R Smith
07-12-2000, 07:16 AM
Hmm... rotten job, this. The clenched end of the nail is usually sunk down into the wood, so you can't grind them off. I've usually resorted to prising up the clench with a screwdriver or similar, until I can get pliers or a mole wrench onto it and straighten it out. Then it MIGHT punch back through the plank without bending again. If anyone has better ideas, I want to know about them too.

John

TomRobb
07-12-2000, 08:31 AM
Center punch the head, drill it off, drive it on through with a skinny punch? John's idea is probably better.

[This message has been edited by TomRobb (edited 07-12-2000).]

Phil Young
07-12-2000, 06:56 PM
Do you mean clenched, ie bent over, or rivetted, ie cut off and peened over a rove, which is a slightly cone shaped copper washer? If rivetted, which I expect yours would be, the job should be a little easier as you are dealing with a straight nail. Drill or grind off the peened end and try to punch the nail out. Or probably better, drill the head off from ouitside and pull the nail and rove from inside.

TomRobb
07-13-2000, 09:17 AM
Just had a DUH moment. Are you only tighteng her up? Why remove the nails?

Keith Wilson
07-13-2000, 09:28 AM
OK, here's another case of "two nations separated by a common language". What the **** is a "mole wrench"? Is it what we colonials call a vise-grip pliers? Or perhaps a crescent wrench? Definitely a nasty job. This seems to be a case where the argument that "traditional construction is easy to repair" doesn't hold.

John R Smith
07-13-2000, 09:54 AM
Sorry, yes a Mole wrench is the same as a vise-grip. Apparently invented by a Mr Mole in Wales. I assumed that Ford meant clenched, rather than roved, of course, although that would be a bit unusual on a 1960s boat I suppose.

John

docgoeckel
07-13-2000, 10:29 AM
come on something as handy as a visegrip had to be invented by us Americans.

John R Smith
07-13-2000, 11:00 AM
No Mike, plenty of carvel boats (especially lightweight racing yachts) fastened with copper roves just like a clinker boat. It's just the clenched bit which is a bit of a surprise - but see the Hereschoff classic "Little Win" which survives over in your USA. She was built clenched, for very light build, and was a real winner in her day. But where is Ford? Only he can save us floundering about like this.

John

Gary Bergman
07-13-2000, 12:35 PM
ORCA's a carvel planked Herreshoff design primarily fastened with bronze ring-shanks {boat nails} with the exception of some silicon bronze screws used in repair upgrades. Last month the surveyor needed to remove a couple to judge their status. Drilled out as mentioned in earlier threads; core drilled. They were in excellent shape with no signs of electrolysis. Replaced with wooden plugs and epoxy. It seems to me that although very labor intensive, replacing a lot of them as dicussed is about the only consistent form of repair.

Dry Rot
07-13-2000, 11:12 PM
Can you "whack" them with a biiiig hammer and a punch? Whatever you drive out, just fill in the resulting hole with RIAC (Rowboat in a can) or epoxy. Then you can use screws after the epoxy cures.

ford
07-15-2000, 12:21 AM
The boat in question is CLENCHED. The reason to remove the nails is twofold, 1. to replace damaged frames, either a new frame or scarfed frame.
2. To replace where possible nails that may have some corrosion.
I like the idea of drilling off the head and drive the nail thru' and pull it out with vice grips.

[This message has been edited by ford (edited 07-15-2000).]

Don Danenberg
07-15-2000, 02:58 AM
Ford, the best approach is from outboard. Center-punch and drill the head off with a bit just larger than the nail shank. When removing thousands, I have my crew use a plunge router fit with a drill bit. All you do is quickly drill the head off (use the vise-grips to remove the built-up nailheads from the bit when run in reverse).
Drive the shank inboard with a dulled spiling pick or suitably sized untapered drift. Don

Roger James
05-20-2002, 09:06 AM
Three years ago I bought a 16' Wianno Jr. which was built in 1952 of mahogany on oak. I turned the boat over to do some refastening, but decided to replace a few planks. After taking off a few planks, I discovered that almost every frame is broken, so I decided to take off every plank below the waterline and start replacing all the frames. I want to reframe it with steam bent oak and replank the bottom with cedar.

The hull had been refastened several times in its lifetime resulting in planks that fell apart under their own weight when removed and frames that gave up trying to hold onto all the screws or broke in two trying.

Is there a reason for using screws instead of rivets other than the labor involved and the problem with the rivet heads and roves interfering with the ceiling? I would feel more comfortable with a rivet going all the way through the frame instead of a screw which grips only part of the frame and tries to split it.

Art Read
05-20-2002, 12:01 PM
Roger. I believe the Wiannos were built upside down on a jig in a similar manner to which Herreshoff built most of his boats. Makes it almost impossible to get inside for riveting. (That's why my boat is fastened with screws anyway...) I think that a lot of re-builds and restorations of these boats DO go with rivets the second time around though. No jig in the way any longer. I suppose if, heaven forbid, I ever have to do any refastening I'll go with rivets too. I'd think that riveting your boat as you put her back together would make a lot of sense. It'll help if you have a small, agile and PATIENT helper when the time comes.

http://www.imagestation.com/picture/sraid15/p80e85cdd912db9e243d146ceb058ffde/fdebc42f.jpg

[ 05-21-2002, 04:07 AM: Message edited by: Art Read ]

Scott Rosen
05-20-2002, 01:18 PM
Roger,

Your choice of fasteners will also depend on the scantlings. Relatively light construction in small yachts means smaller frames that can take a nail all the way through. The thicker the frame, the longer the nail has to be, and you can see the problem with larger boats.

I agree with Art on the Herreshoff method. Herreshoff was into production efficiencies. Screws are faster, less labor-intensive (i.e. need only one person) and can be used when the boat is framed and planked with station molds in place.

Personally, I like rivets where you can use them. Of course even in a riveted boat, you still will need to use screws for fastening the planks to the stem, keel rabet and transom.

Bernadette
05-21-2002, 05:59 AM
it's always interesting to read the variants on different methods...but both drilling heads etc and the other option of prising out the nail end etc work ok with drilling the head the better option. it's also a little alarming to read statements of the like 'voiced' by Mike Vogdes. our entire boat is built with roved copper nails. likewise it was just a matter of choice...to clench or rove! also, hood ends can be fastened with dumps as an alternative to screws.

[ 05-21-2002, 06:00 AM: Message edited by: Bernadette & David Hedger ]

Roger James
05-21-2002, 08:09 AM
Scott,

I should have mentioned that the Wianno Jr. (and Sr.) were built by the Crosby Yacht Building and Storage Co.. The scantlings are the opposite end of the spectrum from Herreshoff's, being 1-1/4" square! I think that was part of the problem -- the radius of curvature, particularly toward the stern is too great for bending such a heavy frame. I suspect that the frames next to the transom were cracked before the boat was even planked!

Bernadette & David,

What are dumps (for fastening planks to hood ends as an alternative to screws)? Is this a "down-under" term? :confused:

Nicholas Carey
05-21-2002, 08:14 PM
Originally posted by ford:
The boat in question is CLENCHED. The reason to remove the nails is twofold, 1. to replace damaged frames, either a new frame or scarfed frame.What we did with PIRATE (she is/was nail-fastened, but not clenched) in reframing here was to section the existing frame with a circular saw (carbide blade) into 6 inch pieces or so and then split them out with a sport chisel[1] and a mallet. Once that was done we cut off the nails with a mini-grinder flush with the inside of the hull -- make sure you're careful with the sparks, though. Finally, we drove the nails out from the inside with mallet and punch. Don't forget to remove the plugs on the outside of the hull -- you want to avoide blowing out the surface of the plank.

I think that worked about as well as anything. It's still a slow and painful slog, though.

I wrote about it the process in some detail (a long stream-of-consciousness rant) a while ago, but I'm not sure what thread it was under.

[1] Sport Chisel. n. chisel used for sporting purposes. Usually has great gaping notches in the blade.