I’m really not looking forward to using the long board so I started today by repairing two small errors that I made when removing the thwarts. In two places I managed to cut the hull, in one place right through the wood and in the other just partially. These have now been routed out and filled with veneer. Once the epoxy is cured these two will also be filled and faired as required.
Since these were small repairs I decided to remove only enough of the hull to accommodate two layers of veneer. The cut through the remaining hull was filled with the epoxy. Both layers of veneer were applied one after the other without allowing the epoxy to cure between the layers. This is acceptable where the shape of the hull is not compromised by the damage as was the case with the main repair.
I could have just filled these with thickened epoxy and left it that way but I decided that dong the job properly was a better way to go and only took an hour or so to accomplish.
More sanding required, though and that I could have done without!
The larger of the two sawing errors. This one went right through the hull.
This error was much smaller and did not cut right through.
Yesterday saw the last layer of the major repair glued in place. As you can see from all the photos and descriptions so far there has been nothing that is inherently difficult about the repair despite the extent of the damage, there has just been a lot of it.
The photos below show the progress of the last layer yesterday and the cleanup this morning.
The next stage is the filling and fairing. The epoxy between the strakes and in any other gaps is put in place level with the wood but it is drawn in to the wood until the epoxy cures and after it has cured you find that there are lots of depressions in the epoxy as a result. All these and any other depressions will need to be filled with epoxy and filler mix and then sanded back to a smooth surface. The epoxy will be put on to the hull in a line about 20cm long and then scraped along the hull using a long piece of plastic like a squeegee. The idea is that where the hull is fair, the epoxy is moved along the hull without leaving any behind but where there are depressions of any kind the epoxy is pushed into the hole resulting in a smooth surface.
In practise the result still needs to be sanded smooth and the process repeated as many times as necessary to fill up all the depressions.
Tedious. My arms are going to ache!
All the strakes have been cut and are held in position by wood and staples.
A close up of some of the smaller pieces of retaining wood. The staples have been placed through the wood and into the hull and not the veneer. This is because the veneer is fragile in this state and removing the staples always causes damage.
Some of the larger retaining wooden pieces where the bend in the veneer means the one staple is not enough to hold the strake in place.
Some additional wood and staples were required to stop the strakes from rising away from the hull.
Another view of the cut strakes in position.
The strakes removed and stacked ready for the next stage.
There are 41 strakes in all ranging from quite small, about 2” in length to the longest around 40”.
Two and a half hours later all the strakes are glued to the hull using plastic staples to hold them tight to the hull whilst the epoxy cures.
Another view of the completed layer having cured.
Two hours later and the major bumps and excess epoxy have been removed using the surform.
From this angle you can see that there is still a lot of work to be done filling and fairing.
After a short break over Christmas I started work on the second of three layers and the result is shown below.
Putting on a layer without having to cut away the hull first is very quick in comparison. In the morning you cut the veneers and staple them in place temporarily using long legged, metal staples with a wooden protector as you can see in the photos of the inner repair before I found out about plastic staples. As each veneer is cut it is stapled in place so that cutting the next veneer is fairly simple to do. About 2 hours is all it took me to cut the entire set of 41 veneers including the fiddly bits. I had a break after that, leaving the veneers in place to bend a little. After lunch I removed the metal staples and stacked the veneers in order having pencilled a number at the top of each veneer so I don’t get them mixed up.
Then begin the great mix up! I use 7oz plastic coffee cups in which to mix the epoxy and these can hold 3 pumps of resin and hardener plus the microfibres. Any more and the cup is too full. I need two cups of mixed and thickened epoxy to glue three of the longest veneers.
This time, unlike the first layer where I put the epoxy on to the strakes I put the epoxy directly on the hull and spread it out a bit. The reason for this is that epoxy, when it is curing, is exothermic and if you mix up too much at a time it can get so hot as to melt the plastic cup. I’ve managed to do that once or twice in my boating career! Because of this, whilst in the pot the epoxy only has a useful life of about 9 minutes at my workshop temperature. Spread it out over the hull a bit and that time goes up to 15 or 20 minutes. This allows me to mix up two or three cups of epoxy without having to worry about leaving it too long before placing the strakes, then having to rush to get the strakes in place before the epoxy is too hard and then making mistakes because I‘m rushing.
So having mixed up the two cups of epoxy and spread it around a bit on the hull I used a notched grout spreader to spread the glue where I wanted it to be. The veneers were stapled in place using the plastic staples this time and any gaps between the strakes filled in with the stuff that squeezed out, and boy did it squeeze out in places!
Repeat this 12 (ish) times and voila, one glued up layer. Leave to cure overnight, then use a small surform to trim off the high spots and excess epoxy.
So, only one layer left to glue in place, today’s job. I’ve already cleaned up the last layer and used the surform so after I’ve had a coffee break and posted this I shall be back to the workshop to start cutting the veneers for the last layer. As this is the outer layer I’ll be a little more careful in the cutting, but not a lot since I still have to use a long board, also known as a torture board, to fair the hull and that will remove many of the imperfections. I’m not a perfectionist in this regard.
The tarpaulin is back in place. It’s been raining and there are a few holes in the workshop roof and I have to protect the wood from the drips. You can’t use epoxy on wet wood. Well, not the epoxy I’m using.
Two milestones have now been reached. The first is the completion of the second veneer layer and the second is the routing of the stepped edges for the next two layers. With these two milestones now reached all the damaged hull has been removed and the replacement can be carried out with no further routing required. Just lots and lots of veneer strakes and epoxy.
The last few pieces of the second veneer layer now in place.
The steps routed, the router guides removed and the tarpaulin taken down.
Another view of the hull.
A close up of the steps cut into the hull. As you can see from this photo I have to go round with some epoxy filler and close up all the gaps. When that is done I shall roughly fair off the repair so far to smooth down the high spots and excess epoxy.
The last few pieces of the second veneer layer now in place.