Fairing the inner hull.

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phmiller
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Fairing the inner hull.

Post by phmiller »

A general question of any of the builders, what is the most useful tool for shaping the inner hull ? I have a ProPrep scraper that has a stainless steel blade that used to work very well. However, it doesn't seem possible to re sharpen it to the same level as the original factory edge. I believe it is no longer possible to buy replacement blades ?

I know about the method of wrapping sand paper around a drink bottle. Ted Moores has written about re shaping the blade of a paint scraper with a file etc. The ones I am aware of in this country ( NZ ) are made of hardened steel which defies any re shaping efforts. I haven't come across mild steel ones.

Any suggestions would be appreciated.

Regards Patrick Miller.
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Jim Dodd
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Re: Fairing the inner hull.

Post by Jim Dodd »

I Looked at every hardware/tool store that I could find.
I've tried making all sorts of scrapers ! I'm still looking.
But here is a trick I discovered.
Scraping into the inside of the stems is tough, as well as the bilge.
Try a 4 or 4 1/2" grinder wheel, or bigger.
Also try those real stiff sander discs, usually red, and real course 36, or 50 grit, they generally come in two sizes.
Image

They won't leave as smooth a surface as a scraper, but it's all I can offer, except. DON'T USE SOO MUCH GLUE ! :thinking

Epoxy can be worked into small gaps between the strips, making a better bond than wood glue !
You only need enough glue to hold the strips together, until you glass the hull.

Keep trying and searching for a better method!

Good Luck !

Jim
Keep your paddle wet and your seat dry!
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Jim Dodd
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Re: Fairing the inner hull.

Post by Jim Dodd »

Found another sanding aid pic.
Image
These are the heavy sanding discs, that I use.

Jim
Keep your paddle wet and your seat dry!
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Cruiser
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Re: Fairing the inner hull.

Post by Cruiser »

The bottles , regular scraper, foam pieces (pool noodles pieces are helpful) ... are all useful tools. In addition I also find that a cabinet scraper set is also very useful for the inside work .... an example from Lee Valley:

http://www.leevalley.com/en/Wood/page.a ... 41069&ap=1

The turn at the bilge and the stern/bow ends are the toughest areas, for a lot of the rest you can also get a floating pad for your ROS that allows it to do some of the contours .... so a lot of the area can still use the ROS, and the others get muscled with scraping/sanding.

I wouldn't try and sand glue, scrape it out, followed by sanding. If you try and sand it, wood and glue both sand and you have to take more off to get all the glue.

Also, the coarser the sandpaper the faster it removes material, and most hulls are soft ... really soft and with very coarse material it is easy to go too far.

Another useful scraper I find is a couple of carbide scrapers, good for wood and glue removal, but also excellent for epoxy runs/drips :

http://www.leevalley.com/en/wood/page.a ... 3456,43390
and
http://www.leevalley.com/en/wood/page.a ... 43390&ap=1 (the corner scraper is a great little helper)

The carbide lasts a long time and replacement blades are readily available.

Brian
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Cruiser
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Re: Fairing the inner hull.

Post by Cruiser »

Reread your post Jim, I like the idea of using the sanding disks at the bow/stern sections, I am going to remember to get a few for my next build. At first I thought you meant to use them on the grinder, then I realized they are hard flat and abrasive and likely very good for a hand sanding vehicle for the tight spaces.

Thanks

Brian
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Jim Dodd
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Re: Fairing the inner hull.

Post by Jim Dodd »

Sorry for the confusion ! Yes hand sanding ! Tha abrasive discs work great in those hard to reach areas.

I like the cabinet scrapers ! They are definitely worth a try !
Thanks for the link Brian !

Jim
Keep your paddle wet and your seat dry!
phmiller
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Re: Fairing the inner hull.

Post by phmiller »

To Jim and Brian, thanks for your replies and suggestions. To add to my original enquiry I've just done a bit more research myself and found something which may be of interest. From the Lee Valley catalogue there is an item which looks interesting, a Veritas Pullshave which has a shallow concave blade that can be adjusted, and best of all can be re sharpened. At $160 is not super cheap but good enough quality to last a lifetime. The blade appears to be of similar size and shape to the ProPrep scraper I've been using. When this was new the results were fantastic. Held at the right angle you could achieve beautiful long shavings just like a well sharpened plane. Nowadays the results I get are not so spectacular.

Regards Patrick.
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Jim Dodd
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Re: Fairing the inner hull.

Post by Jim Dodd »

I primarily use a scraper to remove glue, or smooth down a ridge.
I'm pretty cheap ! I'd have a hard time laying down $160 for a scraper.
A ROS to sand the wood. At a 1/4" thick, I don't want to shave too much off.

Jim
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Cruiser
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Re: Fairing the inner hull.

Post by Cruiser »

Patrick I have that Pullshave, I can't see how it could be of use in scraping the canoe .... I use it primarily on concave surfaces like the inside of a carry yoke, or the neck/handle transition of a paddle.

From a canoe perspective it has a tight radius and you will likely get into trouble trying that on the inside of a canoe.

Just my opinion, although I have uses for the tool, I just don't think that is one I would even attempt.

The best tool for inside is usually patience, there aren't too many shortcuts for the inside, and it is the only part of the boat you constantly look at .... so take the time to make it look good.

Brian
phmiller
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Re: Fairing the inner hull.

Post by phmiller »

Brian,

Thanks for your comments re the pullshave. When I saw a picture of it on line the radius of the blade seemed to compare to the shape of the curve of the ProPrep scraper I have been using so thought possessing a tool that had a re sharpenable blade would suit me fine. The ProPrep scraper worked very well when new, producing lovely long shavings like that from a normal plane. Unfortunately the factory sharpness of this tool is long gone and being stainless steel is difficult to sharpen to its original edge. Ted Moores has written about re shaping a paint scraper for use to fair this canoe inside. I haven't been able to find a mild steel scraper. The ones here are all carbide steel which defies re shaping.

Regards Patrick.
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Patricks Dad
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Re: Fairing the inner hull.

Post by Patricks Dad »

I use my ROS for almost all of the inside fairing. I'm pretty careful when I glue to wipe any inside drips off with a wet cloth. The ROS held on an angle at the turn of the bilge with 150 grit paper works great for me.
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Cruiser
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Re: Fairing the inner hull.

Post by Cruiser »

You can also get a soft pad for most ROS that allow the paper to conform to curves, that also helps the ROS do most of the accessible areas of the inside.


Brian
phmiller
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Re: Fairing the inner hull.

Post by phmiller »

Thanks for the latest batch of suggestions . Patrick.
hughhallhh56
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Re: Fairing the inner hull.

Post by hughhallhh56 »

Howdy

Been offline for a while - finishing that Ranger canoe. Anyways, I use a Richards paint scraper. I take the flat blade over to my bench grinder and give it a curve. Works very well for the first rough leveling. When sharp it slices the cedar like a plane. I end up with nice shavings. The glue comes off easily and if there are any ridges between the strips, they are gone.

After that I use the orbital for the flat parts and a sponge sanding block for the curves. Yes that does mean some elbow grease is needed.

hugh
alick burt
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Re: Fairing the inner hull.

Post by alick burt »

I like cabinet scrapers (made from an ordinary piece of mild steel) for this part of the build.
I have filed a selection of them to varying curves for the different areas of the hull and am starting to build up a nice collection of useful shapes.

Image

Once you have them to shape they work best if given a proper edge by filing followed by an oilstone and finished with a ticketer or a screwdriver shaft (which is what I use).That way they make shavings rather than dust.
I also heard that clog makers in Holland used to use pieces of glass with curved edges to finish their clogs in much the same way though this didn't work as well when I tried it on my canoes.

Cheers Alick :wink
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