3 point track gauges

I plan to make a small 006 (6mm gauge, 4mm scale) 'pizza' layout, and for that I will need a pair of three point gauges to lay the track with. As nothing is commercially available for this gauge (as far as I know anyway) I've made my own.

This type of gauge not only holds the rails parallel to each other but, more importantly for my intended use, automatically gives gauge widening on curves.

I started with a length of 20mm x 5mm aluminium strip, which had the ends machined square before being marked out with the hole positions, noting that the two in-line holes are twice the track gauge apart, in this case 12mm. Also note that the distance between the in-line and single holes, that sets the gauge, must be set at the gauge plus the width of the slot, that is if the slot is, say, .6mm then the holes must be drilled gauge plus .6mm apart, that is 6.6mm in this case. Then, with the Unimat 3 set up as a mill the strip was clamped down and three holes drilled 2.8mm then reamed out to 3mm, using the machine to index the hole positions rather than my marking out (which was done just as a guide);

Once drilled each part was sawn off the strip, and machined to size. I also machined angles on the sides;

I ended up with these;

For the 'pegs' that hold the rail in position I used 4mm brass rod. Each peg had a .6mm wide by 1mm deep slot milled in the end, to suit the code 40 rail that I plan to use;

A gentle touch is needed here, I took a series of .1mm cuts using the fine feed attachment.

The other end of the peg was turned down for a sliding fit into the baseplates, to allow for adjustment on assembly. Here's the parts ready, with the baseplates cleaned up;

Each peg was glued in place with a smear of 5 minute epoxy, to allow time for adjustment. The two in-line pegs were aligned using an off-cut of rail;

The single peg was just set by eye.

Here's the finished pair;

Now all I need to do is cut some wood and lay some track.

Paul.

Update - some measurements have been changed and additional information added. Slots are now .6mm wide rather than .5mm.