Help wanted with how to cut, before I cut.

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Oscarpop

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Can you please help me work out how to cut a piece of teak to act as the pad for the bracket ofmy Hydro vane?

The front face of the pad, that takes the hydro vane bracket has to sit perfectly flat, whereas the face of the teak block that is in contact with the hull has to be shaped to take Into account to the angulation of the hull.

I have taken accurate measurements with a digital spirit level. The angle of the transom slopes inwards at 10 degrees from the vertical.
It also slopes at 6 degrees in the horizontal from the midline of the boat to the port side.
There appear to be no curves just a slope in both the horizontal and vertical plane.

Tomorrow I am going to get my friend to cut the teak with a band saw.

Is it simply a question of setting the saw at 10 degrees for one place, then rotating the block by 90 degrees and sawing that at 6 Degrees? It doesn't seem right.

I also tried it with a block of parmesan and a shape knife, and it still looked wrong. This has nothing to do with sailing. Just wanted
To visualize it

All help gratefully received.

Cheers
 
If in any doubt, get a block of something cheap and easy to work, eg pine or balsa and make that as a trial fit so you get the process right. This will ensure you don't waste that block of teak. You can also get a small bit and use that so you get the process for the angles correct.

I would also not cut it exactly to size with the saw; leave a little green so you can do the final fit on the boat, by hand. One thing is for sure, your transom won't be flat!

Good luck
 
I had to make something similar to go against a compound curve. Make templates out of card for the four outside edges of the square and cut until you have the approx curves you need and transfer to 4mm ply screw them round the square made out of 12mm ply. Finish shaping the 4mm ply edges until all four are flat to the transom and the square face is at the angle you want. Put the square of teak inside the template (sized so it just fits). Shape the face using saw/router/flap wheel/sandpaper until you can run a straight edge across anywhere and the face of the teak touches it all along. If you really do have a flat surface the problem is to work out the angle across the 'diagonal' that making a single cut needs to go. Two cuts at 90 degrees won't do it.
 
Alternative to a teak block is to cast an epoxy block as described in the West book. Seems to remember examples using the technique on the Hydrovane website.
 
You are over thinking the job. Cut an over size wedge based on your fancy spririt level measurements and then get to work on site with a plane, belt sander, chisels, whatever, trying it for fit until it does.
 
Two cuts will do it
First mark top rear edge of block. With block in that orientation cut the side to side bevel. Turn the block on its side and cut the top to blttom bevel on the rear surface of the block.
Putting both cuts on the same side of the block will NOT work and do remember to rotate the block 90° between cuts.
 
I will be doing the same thing very soon. On the Hydrovane website there is a tips page. As far as I know on the vertical axis one of the brackets is hinged the other can work through the angle, so all you are doing is making a pad to compensate for the curve of your hull (port to stbd).

I am not sure what boat you have but so long as its not a huge curve to be made I would simply get some very coarse sand paper or equivalent and stick it (masking tape) to the transom. Make sure you have a fair overlap for the pad. Then 'holy stone' the pad i.e. rub the pad up and down the sand paper until you have your shape, then work your way down through the grades. You will most likely use some sealer which will take up any slight imperfections. I wouldn't tighten the pad so as all the sealant is squashed out leave it until almost gone off and tighten down.

added a link http://www.hydrovane.com/instructions/tips/#4
 
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