FLTS - Flat Lying Trammel Head Set

The FLTS is a multi-purpose tool, consisting of two trammel heads, pivot point, blade post and pencil. In order to use the FLTS you need to attach the trammel heads to a beam, which can be any ruler, square or length of hardwood up to 3/32" thick and 2" wide.

Once attached to a beam, the FLTS can mark out arcs or circles, or lay out single or double  parallel lines. The limit to the size of arcs and circles is determined by the length of the beam being used; you can anything from a 6" ruler to a 10' piece of hardwood.

A conventional set of trammel heads has the point and pencil aligned perpendicular to the work. Typically you hold the head with the pivot point stationary, while you swing the other head in the desired arc. To draw a clean, smooth arc you need to ensure that the heads are constantly at 90 to the work surface. For short arcs and circles this is relatively easy. However, on longer arcs, where your arms are widely separated, it becomes somewhat more cumbersome.

The FLTS resolves this issue by having the heads sit flat against the work surface, thereby increasing the rigidity of the beam and using gravity to stabilize the heads as they are moved about. I found it very easy to draw arcs and circles up to about 40" radius with the FLTS. When drawing arcs and circles of up to 24" radius I used my steel shop ruler; for anything longer I ended up making an oak beam. It worked reasonably well, but there was a fair amount of flexing in the beam; I would like to have been able to use a length of 1/8" thick anodized aluminum that I use for laying out large panels. Unfortunately the FLTS trammels only accept beams up to 3/32" thick.

Conventional trammel heads

MPower trammel head

Adjusting the trammel heads is very quick. The key is to ensure that you hold the trammel heads snugly against the work surface when inserting the pivot post and pencil and tightening the brass pinch bolts. The heads slide easily across the length of a shop ruler. Rather than adjusting the heads to the desired radius and then drawing the arc, I found it easier to lay out the radius on my stock, place the pivot point at one mark, and then adjust the other trammel head so that the pencil tip was exactly over the other mark.

Draw circles and arcs

Cut arcs, circles or lines with the blade

You can also use the FLTS to draw lines parallel to the edge of a board or panel. You attach a trammel head onto a square at the appropriate distance from the edge of the square. Because both the edge of the blade and the arm on the square are in firm contact with your stock you end up with an accurate line. If you slip two trammel heads onto the blade of a square you can lay out parallel lines. I found that this system worked quite well on large panels and sheet goods, but much less so on small boards. For laying out mortises and tenons the FLTS is not suitable; the design doesn't enable you to complete a line across the full width of a board. A conventional marking gauge is much more suitable.

Not suitable for mortise and tenon work

Drawing parallel lines to edge of board

The FLTS comes with a blade post, so that you can cut arcs, circles and straight edges in veneer. By exchanging the pencil with the supplied blade post you can score the lines. While I found that it worked reasonably well for straight lines, I didn't have a lot of success cutting arcs and circles in veneer and cork, particularly when cutting across the grain.

The FLTS is an great tool for drawing arcs and circles up to about 40" and for laying out lines on panels and sheet stock, and this is what I would recommend it for. I wouldn't use it as a replacement for my marking gauge, nor would I use it for cutting veneer. If you don't already have a trammel set though, do take a look at the FLTS. It costs less than a good quality conventional trammel set, and offers you the advantage of laying out parallel lines.

Reviewed July 2010