bevel mystery

[PhilJ]

I am building a 17' power boat with a flat raking transom. Lofting has gone smoothly using Chapelle's "Boatbuilding". However, I am now attempting to obtain transom bevels. I followed Chapelle's instructions (p. 123). When I compared the resulting bevel on the bottom of the transom with the same bevel as it shows in the profile, I found that the one I obtained with Chapelle's method is much too shallow.

This method baffles me because Chapelle generates bevels using the distance between the transom and the "next frame or station". Since the distance to each would usually be different, different bevels would result. Yet he seems to be saying that it doesn't matter whether you measure to frame or station. How can this be?

Can anyone explain how I went wrong with this procedure or describe an alternate method for picking up transom bevels? Thank you!

[Bob Smalser]

I make another partial lofting looking at the boat from the top rather than the end or side.

[John Meachen]

I think I might be able to suggest the source of the problem and maybe describe a cure.I think you may be lifting the bevel as it applies in a horizontal or vertical plane.What you really need is the bevel square to the line marked on the face of the transom.An alternative may be for you to develop the inside face of the transom and to make a pattern of it and than to apply it to the correct face of the transom,allowing for the rake of the transom when setting it to the waterline of your choice.Look along the edge of the transom at the lines on each side and cut to the larger and then plane or spokeshave the bevel.
If you really want,you can pick a number of points around the periphery of the transom and take a bevel at each from the lofting but the second pattern is easier to describe and to do.How are your stem bevels?

[Bob Cleek]

I may not have understood your question, or not be vizualizing it right, but if I did understand you correctly, is it possible that you are taking the bevel based on the lofted transom face which is lofted to the INSIDE of the planking. Common problem. Happens all the time. Results from taking the bevel from the distance forward equal to the transom plank thickness, rather that at the true corner.

Just a thought.