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sveng
Member

Post Number: 1
Registered: 08-2009
Posted on Monday, August 24, 2009 - 4:58 pm:   Edit Post Delete Post

Hi I am wondering if it is worth to buy a canoe wooden frame and recanvas it my self.
the canoe looks like it is in a good shape.
I am a little concerned as there are quite big gaps between the boards (1/8 to 1/4 inch)
I do not know if this is a sign that the canoe has dried out to much and will be to brittl and crack the first time I put it in to the Water.
Any suggestions?
Sven
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ed
Moderator

Post Number: 658
Registered: 03-2004


Posted on Wednesday, August 26, 2009 - 7:56 am:   Edit Post Delete Post

Sven:
You might try posting this on www.myccr.com
There are a number of boatbuilders who lurk around over there and they might provide you with an answer to your query.
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sundown
Member

Post Number: 477
Registered: 04-2007
Posted on Wednesday, August 26, 2009 - 8:38 am:   Edit Post Delete Post

Hi Sven

I concur with Ed... Battenkiller and Graybeard over there would have some good input.

From my view, I'd need a bit more info in order to comment more specifically.

In general, percentage of moisture content is critical in canoebuilding, though. I cannot know if your frame was ever canvased... ie, it had a previous life and someone removed the canvas and never got around to recanvasing (which is what I'm thinking), or whether it was never canvassed at all?

I would suggest that you use a moisture meter to determine what you are dealing with to begin with, and proceeding from there. I strongly suspect your ribs are desecated, and you ought soak the entire canoe for a period of time to swell the wood (carefully) and then moniter the moisture contents as it dries to a suitable state ideal for re-canvassing.

Once it reaches a suitable moisture content, evaluate the gapping at that point, and make your decision then.

No... I suspect I would NOT just recanvas it as-is presently, for the reasons you state.

Regards

Sundown
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preacher
Member

Post Number: 60
Registered: 09-2007
Posted on Thursday, August 27, 2009 - 12:05 pm:   Edit Post Delete Post

Worth it financially? I doubt it.
Worth it spiritually? Yes.

We did this 25 years ago with a canoe builder's guidance. It was a lot of fun. There were similar sized gaps in the planking.

While it's in its current condition, well worth investigating other potential issues. Rot, warp...take it to the pros?

Maybe also look into other coverings. Canvas while classic isn't as durable and is a lot heavier than newer materials that mimic canvas.
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woodcanoe
Member

Post Number: 3
Registered: 05-2007
Posted on Tuesday, September 29, 2009 - 9:30 am:   Edit Post Delete Post

Check out www.wcha.org

They have a builders and restorers directory. You might be able to find a pro near by you that can evaluate your canoe and give you the best advice. They might even be willing to canvas the canoe with you.

Generally speaking, the only time moisture content in wood is critical for canoe building is whether the wood is green, fresh off the sawmill, or seasoned, appropriately air dried. The other big issue of moisture (or lack of) concerns the humidity levels of where you live. Unless you live in a dry climate like Arizona or keep your canoe in a heated building during the winter, you have nothing to worry about.

A moisture meter will tell nothing other than what any good boat builder can, that your wood has reached its EMC or equilibrium moisture content. Your wood isn’t overly dry from lack of moisture but rather a lack of its’ natural resins within. This is something that can easily be rejuvenated with good restoration practices.

Soaking the canoe in water will do nothing for you other than drive you nuts. Your wood will swell and then return to its’ current moisture content. You’ve achieved nothing other than put the wood through an unrealistic expansion and contraction cycle.

By rejuvenating the lost natural resins in the wood and properly varnishing the wood (sealing it) you will effectively lesson the amount of expansion and contraction which is what you want.

Wide spacing between the planking typically indicates a poorly built canoe to begin with. Some builders intentionally built their canoes with spacing between the planks to allow for expansion and contractions (of the planks). But this technique was only due to using lesser quality planking stock and somewhat inadequate building methods.

Sorry but canvas is the only way to go here. Dacron is the other material that is sometimes used in lieu of canvas. True Dacron weighs less, but it is not nearly as durable as canvas is. In fact Dacron has little resistance to abrasion and tearing.

When properly done, canvas is a highly durable and long lasting material. There is really nothing out there that can adequately replace its’ 140 year use as a viable material for canoe building.
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sundown
Member

Post Number: 504
Registered: 04-2007
Posted on Tuesday, September 29, 2009 - 2:39 pm:   Edit Post Delete Post

Woodcanoe

I didnt say "Soak In Water"... I said "soak the entire canoe"... which is precisely what you will be doing as you add resins.

As any woodworker knows, soaking WITH water will raise the grain, thus opening the pores for any resin to soak into... ONCE it is at an appropriate moisture content for "absorption".

The way any woodworker checks accurately for moisture content IS with a moisture meter.

Any "good boat builder" who would determine EMC by running their hands over it, or otherwise opting for 'gutfeel' when perfectly good technology is available at hand to measure it instrumentally... ain't much of a good boatbuilder, IMO.

I could pick apart the rest of your post further, but my goal here in this post, will remain in the future (as it was in the past, and is in the present), the providing of good sound empiral advice.

Regards

Sundown
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woodcanoe
Member

Post Number: 4
Registered: 05-2007
Posted on Wednesday, September 30, 2009 - 8:34 am:   Edit Post Delete Post

Pardon me SVENG, but I need to reply to Sundown. Good luck with your quest to bring your wooden canoe back to life. Your overly dry wood is most likely easily rectified to bring the canoe back to a useable state. If you haven’t already, do check out www.wcha.org (wooden canoe heritage association) they have a wealth of information specifically aimed towards traditionally built wooden canoes.

Well don’t you have everything figured out Sundown. No need to be aggressive toward my opinions, especially when your advice is slightly misleading and at times faulty. We’re just having a discussion.

“I didnt say "Soak In Water"... I said "soak the entire canoe"... which is precisely what you will be doing as you add resins.”

Okay, chalk one up on the board for yourself; this was a misinterpretation on my part about soaking the canoe in water.

To my defense, when you say;

“you ought soak the entire canoe for a period of time to swell the wood (carefully) and then moniter the moisture contents as it dries to a suitable state ideal for re-canvassing.”

You can see how I thought you were talking about soaking the canoe in/with water. After all, the only way to increase moisture content (MC) in wood is for it (wood) to absorb some form of water. Rejuvenating the lost natural oils, which is no more than coating it with linseed or tung oil, will not raise the moisture content of the wood. (Sure linseed and tung oils are liquids and they may raise the MC an immeasurable amount when initially applied, but as the solvents evaporate and the oils solidify into a solid you will no longer have a liquid in the wood which means the MC has not been raised.)

By the way, I think your statement of soaking the canoe with some sort of liquid to increase the MC and then let it dry to suitable state for re-canvassing is a little misleading.

Suppose we were to increase the MC by soaking the wood with water and then let it dry. The wood would dry to its’ original MC prior to soaking assuming that the air temperature and Relative Humidity (RH) hasn’t changed. Your statement further implies that we can somehow magically turn the MC in wood on and off by adding water and letting it dry. What controls MC and determines the amount of MC in wood is air temperature and RH. The only way we can control MC is by controlling the atmospheric conditions that surround wood.


”As any woodworker knows, soaking WITH water will raise the grain, thus opening the pores for any resin to soak into... ONCE it is at an appropriate moisture content for "absorption". “

Again, this is pretty much a false statement. You are implying that the MC needs to be raised for better absorption which is not true.

This technique of wetting the surface of the wood to raise the grain is not done to promote better absorption of the finish. In fact soaking wood with water will not open the pores of the wood. It will do the opposite. It will fill them up closing off their ability to further absorb more moisture. What do you think a liquid finish does? It fills the pores and seals them off so water or moisture vapor can’t penetrate the wood. Have you ever tried to finish a piece of green saturated wood? You can’t because the pores are filled with moisture.

Technically, the drier the wood the more liquid that wood will be able to absorb. This is due to the fact that the pores aren’t “filled” or absorbed with moisture (water). Think about it, bare wood is thirsty for a finish. If we use varnish, which would be used in this case on a wood canvas canoe, the first few coats will soak right in. Soon the pores will be filled and the varnish will begin to build up on the surface of the wood.

If we followed your logic which states “soaking WITH water will raise the grain, thus opening the pores for any resin to soak into” than every time we applied a coat of finish the pores would continue to open allowing for further absorption of that liquid. If this were true we would never be able to effectively finish or seal wood. The very act of finishing wood (varnishing, oiling, et cetera) seals the pores up to prevent further absorption of liquid or vapor.

In regards to raising the grain by wetting or sponging the wood, this is a technique used prior to putting the first coat of finish on. This sponging is done so the grain won’t “raise” when you put the first coat of water based finish on, hence saving you the aggravation of sanding before the second coat of finish goes on. If you had to sand in-between the first and second coat, you risk damaging your finish coating. On a side note, this technique is not widely used, if at all, by small wooden boat builders as their finishes, which are primarily oil base varnish and paint and not water base finishes, rely on a “little tooth” for adhesion. Contrary to popular thought, a premature sanding could ruin the adhesion properties of the finish.


“The way any woodworker checks accurately for moisture content IS with a moisture meter.”

Yes, this is true, a moisture meter will give a fairly accurate reading of moisture content but why spend hundreds of dollars on a device that will only tell us what our “empirical knowledge” already knows in this case? The wood is dry.

A moisture meter is nonsense when dealing with older, traditionally built canoes. The wood in such a case is seasoned and is at an appropriate moisture level. For the most part, the wood is not going to have a detrimentally low or high MC that would prevent one from re-canvassing or properly re-finishing. In less you and your canoes live in a very dry aired climate like that of the Southwest US or keep your canoes in a heated room during the winter in the northeast, natural RH and air temperatures in the northeast will generally yield acceptable moisture contents year round for any task that needs to be performed on an older wooden canoe.


”Any "good boat builder" who would determine EMC by running their hands over it, or otherwise opting for 'gutfeel' when perfectly good technology is available at hand to measure it instrumentally... ain't much of a good boatbuilder, IMO.”

You’re a little off on your assessment of EMC. EMC or Equilibrium Moisture Content can not be measured with an instrument such as a moisture meter. EMC is not a measured value or percentage per say. EMC represents a state of equilibrium that wood is in when it (wood) is no longer gaining or losing moisture.

Perhaps I wasn’t clear enough in my previous post about EMC and what a knowledgeable person could tell you with out a moisture meter. Any wood canvas canoe sitting idle in a barn for several years with out its’ canvas (and presuming that this one is/has been) has most likely or rather its’ wood has most likely reached its’ EMC at some point. This doesn’t necessarily mean that the wood is currently in a state of EMC but what it does mean is that wood is at an acceptable MC. This is what any good boat builder and his “empirical knowledge” will be able to tell you without the aid of some electronic do-dad.


”I could pick apart the rest of your post further, but my goal here in this post, will remain in the future (as it was in the past, and is in the present), the providing of good sound empiral advice.”

This is a little aggressive, don’t you think so? We’re just having a discussion of opinions here with some factual information mixed in. But hey, if you must pick my post apart, pick away, just as long as you don’t pick my nose along the way.



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woodncanvas
Member
Post Number: 1
Registered: 11-2009
Posted on Sunday, January 17, 2010 - 2:11 pm:   Edit Post Delete Post

Without getting into any argument here (I'm a new guy here so just getting my feet wet), I'd agree with advice about WCHA as a great source for advice....I'd also suggest The Wood and Canvas Canoe by Rollin Thurlow and Jerry Stelmok as one of the best written resouces....you might want to check out Canoeguy's Blog, http://canoeguybc.wordpress.com/, from Mike Elliott of Kettle River Canoes (a very good builder and restorer) for more info....as well as his website for articles on restoration such as Care and Maintenance of a Wooden Canoe, http://www.canoeshop.ca/care.html, or How to Fill and Enamel Wooden Canoe Canvas, http://www.canoeshop.ca/enamel.html. There are other resources posted on left side of my blog, http://reflectionsoutdoors.wordpress.com/, including several helpful videos from places like YouTube. Don't be put off canvassing an old canoe. Personally I think that cedar and canvas make for something very special in a canoe....old or new. But then I'm biased.

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