Repairing Minor Damage to your Hull caused by hitting rocks on rapids!
August 27, 2016
How to repair damage from paddling your woodstrip canoe on moving water.
At the Song of the Paddle Big meet this year thanks to Greg Spencer I got the opportunity to paddle my wooden canoe on moving water for the first time.
I have dabbled in this concept a little, partly when I knew no better on the Towy in Wales and when I knew a little more I paddled through Symonds Yat on the Wye but on both occasions I had no instruction so it was great to have Greg and other experienced paddlers with me to help me learn and improve my skills.
On this sort of water with rocks under you it is unlikely that your boat will survive unscathed but do not worry all damage ranging from minor scratches right through to big holes and splits can be repaired and here you will see how I go about some minor repairs.
Looking at the bottom of the hull we can see three different problems. The first is the simplest. These are small scratches that you always get, though after a day scraping in shallow water or a day running water with rocks just below the surface you will have many more of them.
These are easily fixed as they are just through the varnish and do not penetrate the resin layer very far if at all. All it requires is a light rub down and a coat of varnish to have the boat looking like new again.
Next you will notice I have bent the keel band in two places. One is not too bad as it has not bent enough to break the band itself
but on the other the band is broken on one side of the screw hole.
I will bend these back in to place but if the broken area does not go back without much more damage I may have to replace the broken bit.
For those who are often running rivers like this you can see why a boat without a keel is more suitable!
The final problem is an area where a rock has cut through the varnish and resin and just reached the cloth.
This will need to be sanded back and have a cloth patch and fresh application of resin. Whilst not difficult it does require drying time so with two days to go till the weekend when I may want to paddle I decided to make a start on this first.
The first stage is to sand back the damaged area with 80grit to about an inch all round.
Then a patch of fibre glass cloth is cut to go over the damaged area.
Next the resin is mixed and the cloth put on and wetted out.
As it was the end of the day (and a very hot one at that) I left it to absorb resin for about half an hour before removing the excess with a squeegy and making sure the cloth is flat and free of bubbles.
I left it to set as I know it will require sanding between coats to feather the edge of the cloth so there is no advantage in trying to get the coats of resin all on in one go.
Next day I sanded the whole area back taking care not to make any flat spots or leave lumps and bumps particularly just outside the damaged area.
Then I continued with the sanding all over the hull in order to remove the rest of the minor scratches and prepare for varnishing.
A coat of varnish was applied with a brush. I do this covering an area between staple marks (from when the boat was made) at a time, dipping the brush into the varnish about 10mm working it vertically first then finishing brushing horizontally from the dry to the wet area of the hull.
I start at one end working to my right as I go and when I reach the larger areas at the middle of the hull the brush is dipped twice.
The varnish is thinned with just a cap ful of white spirit in an inch and a half of varnish that is in a plastic pint pot.
Drying time is 16 hrs between coats but I actually left it about 24 which is always a good thing to be sure the first coat is bone hard before adding more, otherwise you are trapping solvents under another layer of varnish.
After the first coat she looked like this.
It might have been enough and in fact you can paddle a boat that has not been varnished(as long as the resin has set) but I had given her a fairly hard rub down so decided a second coat was in order and as the forecast was for heavy rain came in to do this on Saturday.