Official Luthiers Forum!

It's officially summer vacation and today I started my Les Paul, joining the top, truing everything, and laminating the body blank.

The Stew Mac plans I have provide cross section templates of the top contours, but I'd to use the Benedetto method of drawing a topographic contour map and drilling holes of the appropriate depth along the contour lines to help guide me. What are some ideas you have for converting those cross section contours into more of a topographic map?

I thought of drawing a horizontal line from the peak of each contour and measuring down every half inch in order to get the depth, but that doesn't work because I don't know the depth from the peak of the top.

If you have a cross-section along the join axis of the body (you should) as well as the ones perpendicular to the join then you should be able to cross reference the 'peak' of your cross-sections with the side-view of the body to get a height map. The side-view will give you the height of the 'peak' on each cross-section and the distance from your horizontal can be subtracted from that to make a height map.

From there (grid of points with heights) you can either make up the height contour map by hand, or bring the points into CAD and run a surface through them (and then use that to make the contour map).

_________________
Bob Garrish
Former Canonized Purveyor of Fine CNC Luthier Services

James, i do not know if it is possible to attach a file here.
but if you PM me your e-mail address i'll send you a contour map for a Les Paul.

there was a really tutorial on here that someone made about doing the topographical map on an electric

_________________
" Blues is a low down achin chill, if you ain't never had it, I hope you never will."

Robert Johnson

Following Bob's advice, I found the absolute peak along the horizontal view and drew a reference line from head to tail. Then I transferred points C, D, E, and F to the horizontal view.



After doing that, I measured the distance from the surface to absolute peak reference line at each point, then noted the difference on the cross section templates. After penciling in the difference, I drew reference lines on each template and made my 1/2 grid lines.



I think the next step will EITHER be A) plot out the same 1/2 grid lines on a copy of the plan, note the depth, and drill the holes, or to B) find the location of like depths on each contour, plot them, then connect the dots. Which would provide me with more of a carving crutch to lean on?

If you want to convert crossections to contour maps, you need to draw in horizontal lines at intervals from a fixed level (underside of cap?) then you can measure out from the centreline to the intersection of that line with the crossection surface and that gives your contour position. So it's horizontal lines not the verticals you have drawn.