First let me describe the installation. I have taken a 2' by 6' section of a walkway and installed TT in the exact center. Now picture a clock face with the no track section between 11--1 and 5--7 (2' wide area). The lead track is coming in at 4. I have two Walthers 3 stall round house structures to be placed at 1--3 on one side and 7--11 on opposite side with a garden track or two if possible. I am going to install brass pem nuts in both floor of structures and plywood to ensure exact placement. The question.....can I first secure the structures to the plywood and then program TT to line up track or program TT and then line up track? At this point I am working with thousandths of an inch and I want to get this right the first time. Not quite sure how exact the movement of the TT is for programming purposes. Any recommendations would be appreciated regarding programming of the TT stops also.
I'm not sure that it would be practical to program the TT then line up the track. In any case if you ever had to reprogram you would have to line the TT to the track anyway. I mention this because I have had to reprogram mine several times.
If you haven't already cut the hole, make sure you scribe a radius for the roundhouse dimensions so you get it placed correctly.
The programming instructions come with the TT. Follow them carefully, it all makes sense after a while.
I installed my track and roundhouse first and then programmed the tt to align. They all worked fine so I am guessing the 'precision' of the programming is quite good. I think Walther's uses a rotary encoder to track the position of the table and it is most likely one with a 0.9 degree step. Just keep in mind there is a 'no track' zone where you cannot place any track around the pit, also defined in the instructions and I believe it is marked on the tt pit underside. I marked the areas with a Sharpie on the plywood (top side) to 'remind' me not to put track there.
-Bob
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