Sunday, September 11, 2011

HowTo: Repair an Outrigger Canoe Paddle. Part 2 Whole paddle repair

This part will be similar to Part 1, but this time with a more involved repair. This paddle is owned by the club, and was not in great shape. It had the usual scratches and dings like Enzo, but it also had significant water damage on both the handle and the two sides of the face. With the extent of the damage involved, I decided that spot-treatment would be ineffective, and the whole paddle must be redone.
Side View: The edges are scraped up badly.
Wood has started to rot.


As can be seen, there is enough damage to the handle that visible splitting of the wood can be seen. Also, the edges of the face are starting to fray. In some of the problem areas it you can even see some red paint from the canoes. The rest of the gallery can be seen here.

Step 1: Identify Problem Areas

2/3 of each side of the handle are worn. There moderate water damage on each side. Both sides are deep enough to observe wood splitting and a crack running down the paddle. The face has similar damage on each side, with fraying towards the bottom. The face itself is in relatively good condition, but could use a new coat of varnish. The handle has quite a bit of water damage and what I guess to be mold. Must be sanded down. A worrying area is the right side of the face, where a visible crack seems to be running down the side.

Each of those areas will have to be sanded down. Remove as much of the rotting wood as possible. Try to sand down into the cracks/splits to avoid sharp edges. Remove varnish from the entire paddle and revarnish.

Step 2: Sand

I sanded the problem areas first. Again used 220 grit sandpaper. I could have used a courser grit, especially considering how much material I ended up removing anyway, but the 220 ensured that I didn't take off too much material at once. This was done all hand sanding. On the damage to the handle I sanded off all the red paint, as well as evening out the cracks.
Majority of the fraying has been sanded down.
Varnish will give it some strength.
On the face, I sanded the outsides until the I got through the fraying wood. I tried to smooth over the crack as best I could. I got down to the point where the crack was small. I could have gone all the way down, but that might have changed the shape of the face or made it uneven from one side to the other. I also could have Epoxied the crack together, but at this point I wasn't ready to start working with Epoxy yet.

After the problem areas were sufficiently sanded, I went about sanding the rest of the paddle. I decided to just remove as much of the varnish as I could from the whole paddle, and redo it. This would let me experiment with how best to varnish ( more on that later) and give me experience on sanding.

Note: do this in a well ventilated area. I did it in my garage, with the door down and no airflow. Not a smart idea.

Step 3: Varnish

Because I decided to redo the entire paddle, I got the liquid version of the same spar varnish. I initially tried using a normal bristle brush, and a more expensive natural fiber brush. Both worked well... for the first coat. But I was not able to clean them thoroughly well enough, and the next time I tried to use them, they were much too hard. Finally a friend told me to try the opposite, the super cheap foam brushes. Use them for one session, then simply throw them away. This worked much much better.

Also I experimented with different techniques for brushing on the varnish. I've found that super thin coats work the best. It drastically reduces the likely hood of runs and pooling. I would start at the "shoulders" of the paddle ( as it hangs face down from some dental floss). I would "paint" from beyond the shoulder, then brush all the way down past the end of the paddle. Again this is to avoid runs and pooling for when you change direction.

If you decide to do many coats of thin varnish this is even less of a problem, as you simply keep brushing until the coat evens out. Be careful as the foam brush tends to simply suck in the varnish, I found myself almost squeezing the brush along the dry areas of the paddle to create a small pool then spreading it with the brush. Experiment to see how it works best for you.

I did one side completely, then the other. After doing the other side, check the reverse( original) side again for any runs that you may have caused. Usually I'll find a few big ones and brush those away. If you do it quick enough the other side will still be wet enough to allow you to brush. If the varnish has gone tacky, don't brush or you'll only end up leaving brush strokes in the varnish.

Step 4: Scuff/Finish Sand

As before, you have to create and abrasive surface between coats. You can use the same scrubbing pad. But I chose to use the 220-grit for the first few coats. The first few coats had quite a few imperfections and drips, so the extra abrasiveness helped me get rid of them. If all else fails, simply keep sanding until you sand away the imperfection and get back to the bare wood.

I must have added about 10 coats of varnish and sanded away at least half of them.

Step 5: Finish Coat

Keep repeating as in Part 1. A change I did do is that towards the end, I switched from liquid to spray varnish. This ensured that the last few coats would be easier to apply and get perfect. This was especially useful on the face, where imperfections were easy to see.

In hindsight I probably could have kept using the liquid varnish, but my skill was not up to it, and neither was my patience.

The results seem to work out fine. There's a visible difference between the handle and face ( the handle I kept using liquid varnish). I was originally planning on doing a final coat on both parts, but by then the paddle was needed and I figured it was "good enough". When the season ends I'll probably try again to perfect the technique.


Notes

The hardest part of this kind of repair was the face. You can see a lot of drips on the face, and its especially easy to see imperfections in the face of the shaft.

Friday, September 02, 2011

HowTo: Repair an Outrigger Canoe Paddle. Part 1, Simple Repairs

For the past few months I've gotten into repairing outrigger canoe, bent shaft paddles. I started into it because my own paddle, Enzo, needed some minor work done. Mostly just some scratches and small gouges in the face and handle. Those were easy enough to repair, once someone told me how. Unfortunately, the web was less than its usual helpful self when it came to repairing paddles. Hopefully this series of entries will help with that.

Figure 1: Scratches
First round is the simple repairs. These include wood that's been exposed to water, and has started to intake water. Simple scratches (shown in Figure 1) or small dings are pretty easy to repair.

Step 1: Identify the Problem Areas
The first question you have to ask is, is the damage slight enough that you can just fix that small part of the paddle, or is it large enough to warrant stripping and re-coating the entire paddle. Most of the time if you're contemplating fixing your paddle, then its probably bad enough that you'd want to fix the whole thing.

On my first paddle, Enzo, the damage wasn't too bad. Enzo is the "Nani" model, all-wood outrigger racing paddle made by Kialoa. Unfortunately I didn't think to take pictures of the damage before hand. The damage was localized mostly at the handle ( from being stood up on the ground), the shaft ( from banging on the gunwales), and the edge of the face ( from banging into the canoe, and general wear). In our Canoe Club, it is considered very disrespectful to stand your paddle face down, so Enzo has almost always been handle down. Even with this, the tip of the face was still banged up, think how bad it would be if it stood on the face all the time!

Step 2: Sand

The next thing you have to do is sand away the varnish. I chose to use 220-grit sandpaper and hand-sanded all the rough areas. Any areas where wood has started to rot, should be sanded until the majority of the rotted wood has been removed. Be careful of removing too much wood. If the water damage looks pretty deep, it might be worth just smoothing it down, and letting the varnish penetrate through the damage. It won't look as uniform, but you don't risk compromising the structural integrity of the paddle.

Step 3: Varnish

For such simple, smaller repairs, I would suggest using a spray varnish. I used Helmsman Spar Varnish. This is used on marine craft and will work well on the paddle. Apply a thin coat on the area, just enough to cover the work area. A mistake I made was not putting enough varnish. You should put enough to coat the area, but not enough to drip. If you're not sure, err on the side of too little. This repair will require multiple coats, so don't worry if the area doesn't look the same as the rest of the paddle.

Put a coat or two of the varnish, about an hour or two apart. This will create a nice base to work with. Let these coats dry for at least 24 hours. Also, before spraying the varnish, take a slightly damp towel and a dry towel, and go over the area. The damp towel will remove the excess saw dust, and the dry towel will ensure that any water from the damp towel won't penetrate into the wood. Do this right before varnishing ( so that dust doesn't have a chance to get back on).

Step 4: Finish-sanding

At this point the area should be relatively smooth. Because these areas are high traffic, we need multiple coats to build up a nice buffer of protection. At this point take a pot scrubber, such as this. And go over the area to create an abrasive surface. This will allow the next coat to adhere better to the previous coat. Make sure you don't take off too much. Now is the time to remove any drips that might have occured, or smooth out any lumpy areas. Consider going back to a 220 grit sandpaper for big drips.

My rule of thumb is to use the scrubber until the gloss of the varnish has been removed. Go over it again with the damp and dry towels.

Step 5: Revarnish and repear

At this point you simple put another layer of varnish onto the paddle. Alternate sanding and adding a coat and let the varnish build up. On Enzo I went for about 4-5 coats total. When spraying, make sure to go "past the area". The spray should be even and consistant. Start a few inches away from the wood and spray a nice even coat. Then keep spraying an inch or two PAST the wood, before changing direction. This ensures that the speed changes do not deliver more or less varnish.

Face of the blade has been fixed.

Here are some shots of the finished product. It came out pretty well. Note: This paddle isn't the same paddle as pictured in Figure 1. I didn't think to take pictures of the damage before starting work.

 The handle still shows some of the damage left in the wood. To remove the rest of the damage would have required quite a bit more sanding. I didn't think I could remove it without significantly altering the shape of the handle. Plus I didn't want the handle to get too small.

The rest of the pictures from this repair are available in my gallery.