Gapping Question (2-Rail Cab Control)

Perhaps Mr. Westcott was handlaying the rail, and not talking about electrical blocks?

Pennslover

Pennslover:

The article is entitled "Two-Rail Track Wiring" by Linn H. Wescott

"Your colored block boundaries are the approximate locations for the gaps you need to isolate trains.  It is best to stagger the gaps rather than to place them directly opposite.  The normal way to stagger gaps is to put the one in the right-hand rail where the engine will reach it first, and the other gap should be about 100 scale feet beyond."

Thanks...

I'm guessing here....but a 100 scale foot staggered block would be about 25 inches long.  If your upcoming block was NOT set to match your current block electrically, then the engine would encounter a 25 inch long dead spot, and coast to a stop.  If the current block and the next block WERE connected to the same circuit, then the 25 inch long blockk would not have a dead spot and the train would continue into the next block with no problems.

The staggered block would be kind of a fail-safe stop area if the next block was NOT connected to the current block. The other rail would not complete the circuit, so the engine would not proceed to the next block because the two rails are not a single common circuit.  An interesting concept....

Pennsylover

Pennslover:

That makes perfect sense, but I wonder how many are actually doing this?  Also, if you have a small layout, this could drastically reduce the number of blocks you have.  The number is 200 scale feet in the left hand branch of a turnout and the left hand gap should lead the right hand gap.

I can imagine this working well for large club layouts where the blocks are much longer.

I have some decisions to make.

Thank you...

Electrically speaking, if the next block had the wrong polarity the wheelsets on one side would still bridge the gap and cause a brief short (full short with all-wheel pickup). With modern polarity switchers, they'd pick this up and throw the polarity anyway. From a construction standpoint, in curves the gaps should be staggered to reduce kinks. This is hard to do with flex track because of the ties.