Sanding, yuck!

Ouch... That's an awful lot of 50 grit... which is too aggressive to begin with, imho. I start sanding with 80 on an RO, but don't get too wild with it, as it can take way too much material off. Then I put 180 on the RO and went over the boat, which finished it off nicely, ready for 'glass... Yes, it's a lot of work, but it sounds like something's not right. :eek:

I can't imagine using that much 50 grit. How rough was the surface before you started sanding? Not just the surface of each strip, but the glue lines between strips as well? Did you try to minimize glue drips when stripping the boat, or at least wipe them off before the glue hardened?
 
Since you're only using the paper until it loses its bite, a lot of it will get used up. It does take time, that's for sure.

Looks like a job well done, and I'm looking forward to seeing the boat all dressed up! What kind of wood are you planning for the rails, seat, thwarts, & decks?
 
I've used a spokeshave on the exterio, before sanding anything. That helped, but not much could be done on the interiorux, but it's a necessary evil!
 
No one that I know likes to sand. I do the following: 1. While laying up the strips, wipe excess glue away with a wet cloth. I would never do this on a furniture joint, but since this entire serface will be removed, it won't affect the final finish at all. 2. First use a T-handled scraper to remove the square joint edges and any bits of glue that remain. 3. On the outside, a faring board with fairly coarse paper like the one you have made, or a bench or block plane set quite fine and used at 45 degree angle to the planking will
get the surface fair and ready for final sanding. 4. On the inside use a covex T-scraper and then a French curve-shaped card scraper followed by any convex block you can construct that will fit the curve and ends where you have to reach. Cover the face of these blocks with sheet cork and then just wrap regular paper around and hold it with you hand. 5. Final sanding can be easily done with a random orbit sander with a thick foam pad like those sold by Klinsgpor for use on 5" Dynabrade sanders. I use these on the inside as well as the outside. Dynabrad pads also fit electric Porter Cables if you don't have air. I also use one of the 5" circular pads with a loop on the back for hand sanding. Do your fairing with moderately course paper or a plane, then final sanding is not so much of a problem. The real pain is doing the inside up near the stems and getting them clean. Some people put a bulkhead here for "floatation". (Ha!) One builder I know does his boats in halves, then glues the halves together and uses fiberglass tape for strength. It looks like a great solution to me, but I haven't tried it yet.

I am reasonably confident with a belt sander, but wouldn't consider using it on the thin, soft planking.
 
Back when I was building a lot of strippers I did it more old-school. I learned strip building from guys who were building them for a living and turning out nice finished boats in about 75 man hours, so they didn't have a lot of time to spend sanding. It is quite possible to go from raw strips and glue drips to baby-butt-smooth wood, ready for glassing in 90 minutes or less and do it using half a dozen or fewer sanding disks. Filler coat sanding after the glassing was abother 1-2 hours. Inside sanding took maybe 2-4 hours, mostly because of the uncomfortable working position and the need for frequent rest breaks.

The key is big power and a light touch using big disk sanders. These are my old stripper sanders. The outside wood was sanded in two passes using a 3450 RPM B&D disk grinder (labeled A in the pic). First pass - 7" or 8", 80 grit floor sanding disks on a hard, stiff phenolic backing plate. The advantage here is that it cuts so well that glue drips and other surface junk are cut down like butter. This allows you to concentrate on getting a nice, smooth, non-wavy surface, rather than all the small ups and downs that many people get with smaller, slower sanders as they work over and over on little problem areas.

Pass #2 with the big disk sander used 100-120 grit paper disks, glued to an automotive "feathering disk" pad (the red and blue ones labeled B). This is a stiff plastic plate with a thick foam pad attached to it. This was a quick pass, just to give a finer-grained surface, free of any swirls from the 80 grit. The hull's outside was then ready to fiberglass.

Inside sanding was done using the same sander and floor-sanding disks, but with a 7" rubber back up pad called a "Black and Decker Super Flexible" (labeled C). It can be leaned on as you sand and will bend to some extent for sanding the inside curves. This is, by far, the most tricky part of big-power sanding, getting a smooth interior without cutting too deep. Finish sanding on the inside was done with a 1/4 sheet orbital sander and a soft pad (E).

After glassing and filling, the cured filler coats were sanded smooth with the feathering disk pad and a couple passes, typically 100 grit for the first and 150 -180 grit for the second pass. When we switched from polyester resin to epoxy about 1978, we also had to switch to a slower sander for sanding filler coats. The 3450 RPM sander was literally melting and smearing the epoxy resin. I bought a 1725 RPM Milwaukee polisher for this (D) and later, when they became available a PC 5" random orbit, which despite being reasonably cheap has held up pretty well through several big boat glassing projects (F).

I'm certainly not suggesting that every strip builder sand their boats with big disk grinders, but that's how production builders usually do it and maintain high quality while drastically reducing sanding time compared to home builders. The bad news is that the learning curve is pretty steep. You can make mistakes in a heartbeat with a big disk, and most folks (including me) chop the crap out of their first boat just learning how to use the sander. A combination of plane what you can, scrape what you can and then sand what's left with a decent random orbit machine, orbital or long-board is probably a better bet.
 

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Well it's probably a bit late now but,

I used square strips and was very careful to keep them in alignment when laying them, stapleless, 4 strips max per night (2 per side). I was also very careful to not use too much glue, I wanted little to no squeeze out.

With that process, I then used a sharp scraper to remove any glue squeeze out, then about an hour with a fairing board with maybe 60 or 80 grit .

When done with the fairing board, the hull is fair, then it just needed smoothing, I used either 100 or 120 in a ROS, and then final sanding by hand with 120 and with the grain.

The inside definately took longer. :)

For me the "magic trick" is to make sure the strips are aligned to minimizes the sanding. I usually put 2 small spring clamps between each station to keep the strips aligned.

Dan

Oh, be sure to wear a mask for protection while sanding, in addition to a vac collection system.
 
Matt,

What's the filler for? :)

Actually, on my 1st I started down the road of using a filler, but stopped as I didn't like the way it was turning out. So no filler for me, just tight joints.

On the 1st 2 canoes, there are no gaps on the out side and just a few total when looking from the inside, and as expected, the gaps were at the chine.

I just let the resin fill them, which created a dark line in those places.

And you'll get no argument about sanding and sucking. :)

Sounds like too much glue.
"they wanted to stick a bit"

And pics, post pics.

Dan
 
That does look like a lot of glue drips to sand off, but not nearly as much as some I've seen.

I'll also say that I've seen "professionally built" strip canoes being sold at Canoe shows, that had a whole lot more filler between strips than you have. You're doing a great job! This will be one spectacular boat!

:):):)
 
Matt,

What kind of glue are you using? If I'm seeing what I think it is, (the inside pic) it seems to be running or bleeding a lot. Which would make the sanding worse. On mine, I just used a std filled carpenter glue, (yellow with wood? filler in it) that just squeezed out into to standing "bubbles", which scraped off fairly easy. In the places, that it was smeared on the surface, it was also harder to get it sanded clean. (read, a pain)

But, no matter, once you are done, it will look great and you'll forget (at least for a while) the sanding.

Nice touch having your daughtor help some, that makes the canoe special for both of you.

Keep us posted on your progress.

Dan
 
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