Reference points
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NY Signal drawn by 3rd PlanIt

NY Signal drawn 
3rd PlanIt by Walter Griffin

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3rd PlanIt provides a new feature for building your model railroad that ensures your track is accurately positioned. This feature, known as Reference Points, is used in conjunction with a few tape measures mounted at fixed locations in the room.

Layout room

Here you can see two of the three tape measures I've mounted on my layout. I bought a 100 foot cloth tape measure from Home Depot and cut it into 30, 30, 20 and 20 foot lengths. Each is mounted at it's "zero" end on a 2x2 that is part of the layout.

You can see the head of a tripod underneath the intersection of the two tape measures. Now it is time to look at the track plan and locate the center of the circle.

Plan view with reference points

The list shows the distance from each reference point to the selected circle, as measured along the tape measures. I can choose any two to form the intersection. I try to maintain an angle of about 90 degrees using the two shortest measures that cross near this angle.

Reference point tapes

The screw in the tripod head is centered at the intersection of two measures. Using the wooden arm I can now mark the circle on joists and place risers with clamps. I used to hold the arm in with a nut, but I bumped it a couple times and moved the tripod. It's much easier to replace the arm after knocking it off - so no more nut.


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Last modified: September 28, 1999