Tacks between planks

Dave Aukes

Curious about Wooden Canoes
Did Peterborough use tacks to establish the gap between planks?
When I first saw this I thought someone did this thinking it would stop the edge from lifting when the plank got wet. But looking more and thinking about it I decided it must be a method of spacing the planks.

There is thousands of years of collective knowledge in this organization please share some of your thoughts.



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Thanks for the reply Rod;
These between plank tacks are all over the boat. In some areas the plank has expanded and the tack is embedded in the plank. I spots where there is no plank gap there are no tacks.
The boat was fiber glassed in its past life and the plank gaps were filled with putty that cured to a ceramic hardness and these extra tacks in the gaps complicate the removal of the cured putty.
If they were used during initial build for some sort of plank alignment they have served their purpose and I think I'll remove most of them.

In the aeras without a gap would you all recommend removing plank material to make a gap?
On my recent Chestnut Bobs Special restoration I encountered lots of "between plank" tacks as well. Not consistently however. It seemed more like a random thing, perhaps to edge-set the planks as needed. I wouldn't bother removing them since the clinched end will likely damage the ribs as you remove them. The damage won't be visible, but why bother? I see no harm in leaving them.

Incidentally, my restoration was also fiberglass clad, and I painstakingly removed the cured epoxy resin in the spaces between planks against the backs of the ribs. Bits of blue paint as well! My concern was that over time the hard resin bits would work out of the gaps, and remain behind the canvas where it might damage the canvas from the back side. I probably won't restore another fiberglass covered canoe unless it's rare or historically significant.
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Yes, I agree with you about not doing another glassed queen. Glassing a canoe causes a host of problems for the next traditional repair/rebuild person.
I decided to remove the material from the plank gaps to allow for wet plank expansion and to prevent buckling (maybe).
Also this canoe has two "won't do it again" issues for me, the fiberglass covering AND a square Sturn.
Famous last words, "I'll never do another 'glassed canoe". I've said that so many times....

I do not think the tacks were put there to set the spacing. They were there to hold the edge down on both edges at the same time. At least that's what I've found myself doing.

I would not remove them. I would not remove any planking in areas where there is no gap either. I try to have no gaps. I also try to use quarter sawn planking. But I've never been able to get quarter sawn planking except once when I sawed my own from a thick plank.
Listen to the experts here. Those tacks were probably put there to hold down the edges of planks, either by a builder who was having trouble with that particular planking, or a builder who simply had this style of tacking. So here's a 4th opinion agreeing that these tacks were probably not put there to "establish a gap." Cedar-canvas canoes are generally built with the goal of having tight planking; your canoe's gaps likely formed when planking shrank because of the way the canoe was used or stored. Most restorers wish for tight planking. This is the first time I've heard of anyone wanting to remove planking and trim it to make gaps where they didn't exist before. I wouldn't recommend removing planking unless truly necessary. Doing so can cause more problems - the process of removing tacks can cause damage, and especially in a 'glassed canoe the planking could be bonded to the ribs, so it may break when you try to remove it. Best to clean out what resin you can (if the process doesn't kill you first) and move on with the next phase of restoration.
When building a new hull, the idea is to plank tightly (but not too tightly) and without gaps.
Some builders (White) even went as far as to lap the edges of the planks.
Skilled builders can generally drive tacks right up to the edge of a plank without splitting the board so seeing someone insert tacks between planks is really unusual.
The following is an example of how the planking is properly fit, albeit not by an expert hand....this was done by either my son or I but it illustrates my point.
I’ve encountered these tacks on Peterborough canoes in the past. I agree with the rest of the guys on an effort to hold edges down. I restored a Bobs Special that had lots of them, in addition to a lot of plank cupping. I used a wet towel and iron to warm up the planks to tack down the cupped planks. I probably doubled the amount of tack on that one. I attribute it to flat sawn planks.
This is a great discussion I'm enjoying it and one always picks up knowledge along the way.

Mitchael, as it relates to this 1950s Peterborough I'm mostly leaning in the direction of option #4 in your Wednesday post.
I have no plans to remove any planks, or tacks, if needed I can create a planking gap in-situ with a tool I made. Today with new builds it appears "no gap" planking is the preferred goal so I'm not going to mess with any plank gap issues.

On this canoe all of the 18+ foot planks are flat sawn with gaps. Looking into the back lite canoe it looks like the walls of a tobacco drying barn.
Some of the planks were cupped a bit but they don't show signs of shrinking. After removing the fiberglass cover most of the plank cups relaxed. To me it looks like back in the 50s Peterborough was building with gaps. That really bothers my OCD brain, I like the no gap look.

On a new canvas covered canoe with flat sawn planks do the "no gap" planks dry out as quickly as quarter sawn?