Another filler thread.

mmmalmberg

LOVES Wooden Canoes
I think I've read about 50 of them:). Just a couple of questions.

I have just under a pound of white lead that I'd be happy to use for the '52 OTCA project I've just started. The original canvas is in amazing shape but after 70 years or whatever the filler has come to the end of its years.

Looking at the recipes below, (thanks Benson!), it looks like the amount of lead needed is somewhat open to interpretation and a pound would suffice for one canoe (and if two coats of filler then I could perhaps throw it all into the first).

I understand Silex to be silica but I'm not sure what mesh. I have 80 and 325. The 325 would be quite smooth. ?

From the recipes below it seems I'll need about a gallon of filler for one canoe, does that sound correct?

What is "varnish mixing oil" and what is Savasol?

Interesting that in '58, whiting (calcium carbonate or chalk) replaces the bulk of the lead. Does anyone know the functioning of the whiting?

I'm open to either adding lead to the best of current commercial fillers (unclear to me which would be in first place) or coming as close as I can to the original formula which has worked extremely well from what I can tell.

Thanks for any answers or thoughts!
-Mark
[manufacturers]Old Town Canoe Company[/manufacturers] 1947 Recipe (Courtesy Benson Gray)

  • 25 1/2 pounds white lead (or 20 pounds)
  • 70-75 pounds Silex (or 90 pounds)
  • 6 gallons boiled oil
  • 5 gallons varnish mixing oil
  • 3 gallons Savasol #4
  • 1 quart dryer (japan or Pratt & Lambert Liquid)
  • makes 14 gallons, enough for 14 canoes

[manufacturers]Old Town Canoe Company[/manufacturers] 1953 Recipe (Courtesy Benson Gray)

  • 75 pounds Silex (100 pounds 1959)
  • 25 1/2 pounds white lead (17 pounds whiting, 8 pounds lead 1958)
  • 1 quart dryer
  • 5 1/2 gallons linseed oil
  • 8 quarts Savasol #4
  • 4 gallons varnish mixing oil
  • makes 25 gallons
 
This may not answer any of your questions, but I'd just hit up Rollin at Northwoods or Jerry at Island Falls for a gallon o' filler. It's just a lot easier to grab it from them while you're ordering tacks new canvas, bedding compound, etc. Their fillers are based on the recipes above without the lead. The main purpose of the lead was used as a fungicide/mildewcide. If these are a concern of yours there are other things you can try like buying mildew-resistant canvas. I think it would be prudent to forego the use of lead. For your health and that of whoever inherits the boat after you. Plus it will save on the overall weight.
 
Thanks, I'll think about those points. Weight's not a concern as I'm only looking at about 3/4 lb. of lead carbonate (a fluffy powder). Substituting microballoons for silica is a weight-saver but it is not a substitute except as a thickener (maybe that's its main function anyway?), I mean basically you're replacing a rock-hard substance with air bubbles.

Regarding modern fungicides/mildewcides, does anyone know what they actually are? I wonder if the chemicals themselves are as enduring as lead. It doesn't seem like anything is made these days to last more than a couple of years... It's certainly a fair point regarding the next person that re-canvases, if they don't know there's lead filler used. I do imagine the little bag of lead I have is going to make its way to the environment someday somehow. But perhaps in a less accessible form... I appreciate your comments.

Is zinc used as well for this purpose? I have plenty of that as well:)
Here's a product I just found made from crab shells!
 
You can purchase pre-treated canvas from Northwoods Canoe. It has anti microbe properties. As far as I know Rollin is the only one that sells it.
 
The 1 time I tried mixing my own, (from the recipes on the site) it didn't work and got VERY heavy. (and not from any lead)
I haven't tried it again.

I do add one of those midewside packets from the paint dept of Home Centers to the filler.
I don't know if it helps the canvas, but it sure kills the bugs that stop on the canvas.

Dan
 
I'm just astounded by the great condition of the canvas on this canoe, given the age and the condition of the paint, including behind the keel and stems, where the canvas looks pretty much like new. They sure got something right:)
 
OK I've got a minute here while I'm in the shop on Sunday. 43 oz. boiled linseed oil, 21 oz. mineral spirits, 34 oz. enamel paint.(Gray Rust-oleum) 2 oz. japan dryer, 6 1/4 lbs. silica 300 or 350 grit will work. 2 oz. spar varnish. Add your mineral spirits last so you can make it as thick as you like. Add some mildewcide from any paint store. This will make one gallon. It's your standard mixture that works great. But if you only need a gallon or two your probably better off buying it. If you make it make sure you wear a mask when handling the silica. Good luck. I'm sure everyone has their version of this. This is just what has worked for me every time.
 
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OK I've got a minute here while I'm in the shop on Sunday. 43 oz. boiled linseed oil, 21 oz. mineral spirits, 34 oz. enamel paint.(Gray Rust-oleum) 2 oz. japan dryer, 6 1/4 lbs. silica 300 or 350 grit will work. 2 oz. spar varnish. Add your mineral spirits last so you can make it as thick as you like. Add some mildewcide from any paint store. This will make one gallon. It's your standard mixture that works great. But if you only need a gallon or two your probably better off buying it. If you make it make sure you wear a mask when handling the silica. Good luck. I'm sure everyone has their version of this. This is just what has worked for me every time.
Thanks. Yeah I do ceramic art and make all my own glazes etc. so I have good masks and habits:)
 
Thanks. Yeah I do ceramic art and make all my own glazes etc. so I have good masks and habits:)
Having once been a ceramics major I now understand why you have white lead laying around. I had a ten pound bag of it when I left school but got rid of it many years ago. Once I discovered canoes I wished I had kept it but it would have just encouraged me to try to mix my own filler. I always use what is commercially available and never had any problems.
 
Having once been a ceramics major I now understand why you have white lead laying around. I had a ten pound bag of it when I left school but got rid of it many years ago. Once I discovered canoes I wished I had kept it but it would have just encouraged me to try to mix my own filler. I always use what is commercially available and never had any problems.
I'm actually torn between using it for the canoe and using it for some of the unique things that can be done with it in ceramics, specifically chrome yellows and reds which are like no other. But yeah I've not actually used any for decades and I have less than I thought (a good thing) but enough to do something good with:)
 
In the FWIW category: For a while, I could get canoe filler here locally with lead in it. I used it on maybe half a dozen canoes. I really noticed very little difference, if any, over the unleaded fillers that are commercially available. I think the mildecide properties of lead are also probably negligible. There are other mildecides that work better too.

I don't think it is worth risking the potential health effects which are real.
 
Thanks Fitz. I think that's clearly a viable point of view.

What would be great to know is whether canoes made in the post-lead era, say the 60's or whenever it switched, fared as well as those from the leaded era. Are many or any 60's canoes still floating on their first canvas? The thing is I don't know how much of a next generation of canoe restorers there will be, and certainly there are almost none already south of the northernmost states in the U.S., and I'd love to have this canoe (bought new by my grandfather in 1952) be part of the family for at least another couple of generations.

A similar question is, what is the long-term durability of modern mildewcides, and do they decay in any way over decades of time? I started trying to find out what the actual chemicals being used are but didn't get anywhere with the time I had... In today's world, something that works for 5 years would be considered long-lasting, so I can't assume anything about the durability of modern products in general, know what I mean?
 
I have a several canoes that were canvassed in the 60's rocking the original canvas. I also have one that was recanvassed in the 70's with a perfect canvas. On the other hand, I have one that was built and canvased in the mid/late 70's that needs a fresh canvas. In each case the main determinant of how well the canvas has held up has been how the boat was stored. The three with good canvases were all provided with good indoor cover when they were not being used. The one that needs a canvas sat outside on a porch, undercover but outside where snow could sit on it and where rain could run down the sides and accumulate near the rail tips. The canvas in those areas has pulled away from the planking and decayed. The boat is useable but it needs a canvas.
From my perspective using a current lead free filler on a treated canvas and letting it cure properly before painting it achieves great results. If the boat is stored dry the canvas will last for years... The canvas on my Morris is now almost 40 years old and even with really heavy use it looks like it was just done.
Before there were Royalex hulls wooden canoes were used with abandon for anything that you would want to use a canoe for and many of them were not very well cared for. They got pulled up on shore and flipped over and would sit like that for weeks or longer. The ones we are building and restoring now tend to get much better care. Due to replacement and repair cost very few folks still use a wooden canoe as a "beater".
Done correctly and properly stored and barring incidents your canvas job could last you another 30 or 40 years and probably longer if it doesn't see really hard use. It could literally last forever if it just sits in storage.
 
I have to admit it seems clear to me with this canoe that most of the decay and damage is not from its time in the water but from how it was stored when not in use. Most of which was well done but in its long life it had to have seen some number of winters without cover or with with cover but outdoors.
 
Can't believe my grandfather let us treat his new canoe like this! I remember flipping it and playing beneath it with my brother and uncle very fondly.
 
Mark,

You are way over thinking this.
Canvas is a disposable, a maintenance item, put it on, fill it, paint it and use it.
When it's needed down the road, replace it with a new piece.

Dan
 
Seems as good a time as any to toss in the epoxy fill. I havent fooled with traditional filler for the last 7 or 8 canoes. cost is comparable, may be some more sanding but thats in a week instead of months. Anyhow, i'll just back away slowly now....
 
Dan - No doubt true. 'Though I doubt my future ability to do something like this. I have terrible arthritis along with a few other health issues. More likely it will get used 'til it's not usable and then, with luck, 50 years later one of my great grandkids will pick it up and do something with it:)
 
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