Countersunk Screw Basic Steps Info Needed

Brian J Knudsen

Enthusiastic about Wooden Canoes
Hello,

I have a 1922 Ideal Model that I am excited to begin fixing up. It is still cold where I live so I can't strip the canoe yet, but I'd like to remove the seats and thwarts and strip them in my basement. The canoe has countersunk screws in the seats and thwarts. I am looking for information on how to remove the seats and thwarts. I have seen a number of general depictions of how to install countersunk screws, but none that explain how to remove countersunk screws. I imagine that I need to drill through the "plug" to get to the head of the screw and then remove it like any other screw. I'm not certain of this though and I'm also concerned that by drilling through the wood plug on top of the screw that I am going to strip the head of whatever type of screw is hidden.

Thank you for any advice.
Brian
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Hi Brian,
Sometimes if the old glue is dried up you can pop them out by tapping the screw up from underneath. I like to double nut the screw ang hit that. It keeps you from boogering the threads.
If that doesn’t work a hole drilled into the plug will help you chip out the plug.
When reinstalling, I like to epoxy the screw head in the hole so that someday if you need to tighten the seat the screw won’t turn, however it may cause problems for the next guy that tries to remove it!!
 
Brian...this is a nice boat and mine is a 1908. Be careful when getting the plug out as if you tap from below and the circumference is not loose all the way around, you can get a splinter and it is not pretty if it is sizeable. Make sure you know what is going on there. May support the edge with a drilled block or get out your dremel and sacrifice the plug.
I know the turning seat bold all too well. So snip off the head of a brass brad and drive in at the slot edge at a 45 degree and tap/bend the shaft into the slot. It is easily removed down the line....if you remember it is there. Or I use a little rotary disc in the dremel ans grind a slot into the bolt shaft below. A screwdriver in the slot will hold the bolt from turning. Make sure to clean up the slor as it may be sharp. And Brian, you should consider NOT stripping in the basement., for obvious reasons. NO
Have fun, Dave
 
Thank you both for the information. I’ll see if I can get another nut onto the screws and tap them to see if I can get any movement. How deep typically is the plug? I'm also thinking of putting a little WD40 on a couple of the nuts that are not moving. Do you know if the WD40 would stain the wood? I've read that it can actually be used for removing stains, so I assume not, but no harm in asking.

(I've used EZ Strip that is low VOC and advertised as safe for indoor use without trouble in the past. I hope it works)
 
Brian,
I forgot to mention that it helps if you run the heat gun on the plug to soften any glue that may be stuck fast to the plug.
Let us know how you ended up solving the issue....
 
It is very unlikely that the machine screw is slotted. It probably has "ears" below the head that bite into the wood. I usually spray the nut and screw bottom with WD40 and see if the nut moves easily. If not, screw another nut onto the screw while holding the original nut with a wrench. If that doesn't work, use a hack saw and cut off the nut. Of course, that will require a new screw upon re-assembly . Observe the other above mentioned methods for carefully removing the plug.
 
"Do you know if the WD40 would stain the wood? "
Yes, sort of. It will soak in and persist as the key ingredient of WD40 (well, originally, anyway) is light fish oil.
 
Attached is an image of these "Fin-Necked" bolts. I tried looking for them a few years back, but the Fin-Necked bolts being made today are very different from these, and are entirely unusable for canoes. The point being, try not to damage them, as they're basically irreplaceable! The seat bolts for this canoe are bent, I'm not yet sure how it's going to go back together...
 

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Rob, It's not likely to stain through old varnish, and I remove seats before the canoe goes to the stripper. The stripper bleaches the wood after he strips it so I have never had a problem.
Paul, If you need some seat bolts, PM me your address and what size you need. I probably have the size you need because I usually replace them with slotted brass epoxied into the inwale.
 
"Fin-Necked" bolts.


Wow, what a coincidence. I had never heard of fin necked bolts until last week when I saw them being fabricated on "Acorn to Arabella", a YouTube channel. Theirs were a larger scale but same purpose; to keep the bolt from spinning when a nut is installed to tighten.
 
I have removed some of the countersunk screws on my 1922 Ideal by tapping on them from below as suggested. Some of the screws are still in the inwale because they wouldn't move and I didn't want to force it. I will use a heat gun and try again when the humidity goes down. I don't know if humidity makes a difference but I assume the wood in my rails is as swollen as my door frames.

At least some of my screws are bent, corroded, or stripped so they will need to be replaced. Does anyone have a good replacement idea for countersunk screws?

Also, would it be horrible if I glued a plug into the countersunk screw hole and replaced the countersunk screws with new diamond head screws?

Thanks to all for your ideas.
 
Again, Brian. Don't know what came out, but for authenticity I would not bother to go the Diamond route and replace with slotted brass or bronze and put n a new plug. Plug cutters are nice to have around. You can secure the slotted heads as I mentioned above. You are doing fine with the removal of some. Just be patient and try different approaches. If these bolts are are not finned I can't imagine they will not release sooner or later. Have fun none the less.
 
Hi Brian. I agree with David (dtdcanoes) about not changing to diamond head bolts. The latter are very nice, eye-catching, so I understand the temptation. But the vast majority of Old Towns have diamond head bolts. Appreciate that your canoe is special. It is a fairly early example and a nice model, and in those days they were especially well built. Yours appears to be in outstanding condition, a prime candidates for a careful and proper restoration.

Even though the diamond head bolts are nice, the more Old Towns you see the more you will appreciate the uncluttered look of your gunwales with their bunged bolt holes. This is especially true in an Ideal model. That old mahogany will be absolutely stunning if you do a good job of cleaning it up and refinishing it.

As is often said here, it’s your canoe and you should do what you want with it. But in my personal opinion, this one will be much nicer and much more appreciated if you keep it as is and leave the diamond head bolts for newer Old Towns.

Michael
 
Brian.... Go to eBay and look for 'Wood Plug Cutter'. A set of various sizes costs little.
 
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As to "authenticity" --

Diamond head bolts were introduced by Old Town in 1922. See:
https://www.wcha.org/forums/index.php?threads/o-t-diamond-head-bolts.16556/
http://www.wcha.org/forums/index.php?threads/1911-aa-old-town-charles-river.17254/page-2#post-89362
see also with respect to the Charles River model and diamond head bolts:
http://www.wcha.org/forums/index.php?threads/old-town-id-from-partial-serial.14864/#post-78680

Our 1922 Ideal has diamond head bolts:
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Your 1922 Ideal has countersunk bolts -- for a 1922 OT canoe, it would seem that either would be "authentic."

Most folks would agree that bolts countersunk in a mahogany gunwale and covered with a mahogany bung are more elegant looking. But anyone who has had to remove an old seat with old bolts would probably agree that diamond head bolts are more practical.

I while back I had to remove a seat from ours in order to replace a broken seat rail. It was fairly easy to remove the seat by driving the bolts upward a bit from below by tapping easily with a small mallet -- the seat did not want to simply drop down because the bolts had been bent and/or seated at an angle by years of use, and also the seat rails were quite tight against the planking/rib. It would have been a more difficult task with countersunk bolts covered by plugs. In my case, it was a no-brainer to stick with the diamond head bolts when I re-installed the repaired seat/

However, you already have the countersunk holes, and you will have to make plugs one way or the other. In your case, I would restore it as it was built. Just don't glue the bungs in with epoxy, in case they have to be removed in the future. Simply using varnish as a glue for bungs is common, gives a waterproof bond, and makes future removal relatively easy should that be necessary.
 
Here are some pictures of the “fin-necked” screws, as I’ve read they are called, and the holes I’ve created getting them out.
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I have managed to get 4 out of 14 of the "fin-necked" countersunk screws out. I've used a heat gun and a variety of hammers & wrenches to tap on the other screws without success. I have a few questions that maybe others might help with.

Is it possible to revarnish the canoe without taking these countersunk screws out? Do I really need to take them out? What are the drawbacks if I don't take them out?

The fin-necked screws are in mixed condition. Some are good, some are bent and stripped. Is there a replacement that works well that anyone knows of?

Thank you all!

Brian
 
Nothing says you need to remove these screws. Though I'd recommend screwing on a nut then wrapping the nut & threads with tape to keep goop & varnish off. When you're ready to use it removing the nut will help clear the threads.
 
I don't know of any source for either carriage bolts or fin bolts in the size that is usually used in OT canoes. The smallest carriage bolts I've come across in bronze are 1/4-20. (For bolts, including unusual ones, I generally use Bolt Depot ( boltdepot.com -- very good service, good selection, and you can generally buy individual bolts as well as in bulk). I suppose you might be able to use a 1/4-20 carriage bolt, but I think the head might be too large.

Perhaps another option, which I suppose some might consider sacrilegious, would be to grind the points off the head of a diamond head bolt so that it would fit into the existing hole, and then put a plug over it.

Bent bolts can often be straightened enough to reuse -- lay the bolt on a small stick or board, and place another over the threads, before hammering the bolt more-or-less straight. You might run a nut up the bolt before attempting the straightening -- running the nut off can help get any damaged threads corrected. In some cases, bolts, especially seat bolts where seat hangers are used, get bent from use, and may actually work more effectively than a new straight bolt. If the threads are actually stripped, I think replacement is probably the only option.
 
Bronze carriage bolts at Mertons’s Fiberglass
10-24
In many lengths. Sometimes I grind the head diameter smaller
 
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