Tuesday, 30 August 2011

Epoxy coating and names

Following the advice of other Goat builders I am epoxy coating as much as possible before the boat goes 3D as it is much easier on the flat.   I have found that I get the best finish when I apply 2 coats of epoxy wet-on-tack then leave to fully cure, the surface is then washed to remove the amine blush, abraded to a flat surface and then a third and final epoxy coat applied.   This gives a really tough and attractive finish.   I have tried applying three coats on wet-on-tack but the finish always end up being a little rough so although my method is a lot more work it gives a much better finish.  The final epoxy coat will still need abrading before it gets a protective coating of varnish or paint but at least I know the wood is fully encapsulated so it won’t absorb any water.

So far I have applied the first two coats to epoxy to one side of all the bulkheads, the dagger board case and one hull side.   Unfortunately there is only so much room to lay out all the pieces for coating so it is going to be done bit by bit.  Because I am mixing up some larger quantities of epoxy there is a chance that this could heat up in the pot really fast and set before it is used so the tip I learned was to pour the epoxy on the wood before spreading it out quickly with a plastic squeegee or spreader. The epoxy can then be tipped off with a foam roller or brush that leave as an even coating.

The mast was epoxy and glass coated when it was built some months ago but I was never really happy with the finish, I did it on a day when it was warming up and as a result there was some out-gassing of the wood that had left a finish that really is not great and I have been thinking about sanding it all off and recoating ever since.  What had been holding me back is that this is such a waste of time and epoxy but it had been annoying me.  I have now run over it with a sander to clean up the first two coats and I think it will look ok-ish once it had another coat so I think I will leave it as it is for now and get the boat built.  If it continues to annoy I’ll have to take care of it when the boat is built.

My eldest son had been helping me this weekend, he is only 4½ but I’m pleased that he wants to be involved.   We have been discussing names for the boat, I would like a play on the Goat Island Skiff name but he is more interested in Sharks, these are the options we came up with, I’ll let you work out with who came up with each name.

Son of a Goat

Super Shark

Goatee boat

Shark Bite

Goating fast


Goat Afloat

Shark Killer

Vote Goat!

Any suggestions, answers on a post card…..

Sunday, 21 August 2011

Bulkheads, dagger board case and chine logs.

Since my last posting I have manged to snatch a few hours here and there to get some more work done on the goat.  Bulkheads 1 and 4 are now complete apart from fitting a waterproof hatch of some type so that I can get into the buoyancy tank for storage and drying out if necessary.  Below is a pic of the full set, BH1 to Transom (still without a ruder hole or outboard engine cut-out).

The dagger board case has also been cut out and assembled but not finished.  Below you can see the internals of the case having had a couple of coats of epoxy to seal the wood.  I was thinking of adding some glass mat to the inside to add some abrasion resistance but with only 3mm of clearance and final finishing of the dagger board to be done it will be left with just an epoxy coating.  The aft and possibly the front end of the case will have a tough rubbery foam applied so that the dagger board has some degree of protection when we touch the bottom (at speed).

Lastly, the chine logs have been cut down to size and temporally held in position using a few screws to check that the cedar takes the curve with no problems, as it turns out I need not have worried as it is flexible stuff.  A few builders have suggested trimming the inner-top corner of the chine log to lose the sharp edge and remove a potential dirt and water trap, both of which are good reasons to get the router out.  As you can see below the chine logs have a pleasing bevel and I'll hopefully get these glued up this week.

Monday, 1 August 2011

Bulkheads, transom and hull sides.

A great weekend of GIS build progress, it was a shame to waste some excellent sailing weather working on the goat but very satisfying to make excellent progress.  She is such a simple boat to build I’m sure that anyone with the space could knock one together so top marks to Mr Storer for the design.  The hull sides have been cut out, trimmed to shape and joined.

BH2, BH3 and the transom have also been cut out and their framing fitted. BH2 still needs it’s access hole cut as does BH3, however BH3 may stay solid with an additional bulkhead fitted under the seat to make a water-tight compartment for stowage and reducing the amount of water the the boat after a capsize.

Lastly I have also made the stem piece, the instructions were somewhat minimal ("make stem piece") but all the info was available in the diagram and it is good for builders to have to work these things out rather than being spoon-fed instructions.   I wondered about how to make the required shape for a while  as the width changes from top to bottom then attacked the chunk of cedar with a plane to get the required width and then a Surform that made really quick work of shaping.  The Surform made material removal both quick and easy but was surprisingly accurate.   I shaped the stem of the rocking boat using a surform and it really worked well.  Pic below of the stem piece part way through shaping.