OK, now unfortunately comes the hard part. If you are great at drawing smooth, free curves, then just mark the foam with these measurements for the three places you cross-sectioned (nose, mid, tail) and connect with smooth lines. I am no artist, so I came up with a way to ‘morph’ the cross-sections into one another smoothly. Here goes:

Put the measurements in columns (numbers are not to scale, just what I measured on the screen)

Middle of board section: Width: 5.12 Thickness: 1.65

Rail Band Horizontal measurement Vertical measurement

red (45deg) 4.09 .63

blue (60deg) 3.54 .40

green (75 deg) 2.53 .48

magenta (85deg) .98 1.22

OK, now that you have all of the measurements (you have to do this for all 3 cross-sections), you have to normalize the data to the cross-section width and thickness. Sounds complicated, but it is just taking each horizontal measurement and dividing it by the width of that section (for instance, above, the red rail band’s horizontal factor is 4.09/5.12, and the vertical factor is .63/1.65). Here is what you end up with for the factors for the above cross-section measurements:

Rail Band Horizontal Factor Vertical Factor

red (45deg) .8 .38

blue (60deg) .69 .24

green (75 deg) .49 .29

magenta (85deg) .19 .74

You will end up with three sets of these factors. They will differ some, and the hard part is how to change them along the length of the board so that a smooth transformation between rail shapes takes place. I use Excel to draw smooth curves between them. We now have to establish a coordinate system.

So, now you have three sets of factors, and three places on the board, nose, middle, tail. Usually, this means 12" up from the tail, 12" up from the nose, and on or near the midpoint of the board’s length. Let’s say you have an 8 foot board. So, the ‘tail’ cross section will be at 1/8 up from the ‘very tail’ of the board, the midpoint at 4/8, and the ‘nose’ at 7/8 of the board. These will become relative locations on the board. You should have something like this for each rail band:

1st rail band (red)

Location Numerical Relative Location Horizontal Factor Vertical Factor

very tail 0/8 or 0 x x

tail 1/8 or .125 from measurements made at that cross-section

```
2/8 or .25 x x
3/8 or .375 x x
```

middle 4/8 or .5 .8 .38

```
5/8 or .625 x x
6/8 or .75 x x
```

nose 7/8 or .875 from measurements made at that cross-section

very nose 8/8 or 1 x x

All of the ‘x’ places are numbers that have to be filled in by the smooth curve. Once you have all of the factors for all of the positions and bevels, you just measure the blank at all the positions (width, thickness) and multiply the Horizontal factor by width at that spot on the board to get where the measurement is for that bevel, same for the vertical measurement.

I made a spreadsheet to make all of the calculations for me, as it becomes very tiresome. All I have to enter is the board’s measurements and the measurements from my drawn cross-sections, and it spits out everything. I print it, and layout the measurements on the board. I tape off the rail bands with 3/4" packing tape and use a planer to take large pieces of foam away, then use a sanding block to hit the tape exactly. I peel the tape, and you have a bevel, same side to side, and no guesswork involved.

I am no sculptor, and most shapers definitely are. As a student, I cannot afford to buy 3 blanks to learn (i.e. make mistakes) with, so I had to make it count on my first one. That’s how I came up with the method. It takes a LOT of time to do the layout of the measurements for every bevel, but the end result is nice. Here are the first two top bevels, you can see I have started marking the ‘vertical’ measurement for the 3rd bevels in already…

That is the short version of how I do it. I have to get back to studying… If anyone is interested, I can explain more when I have more time.

JSS