2 questions...

[bogp40]

If your running a 28" outside radius, use a clearance of 2 1/2" track centers giving you 25 1/2 " radius inside. The 2 1/2" is more than enough for combined inside pilot overhang to clear a side overhang of the 85' cars on the outer track. If you have any doubts, layout some flex and check with the offending equipment.
Try not to go under 24", you could experience troubles with the longer rolling stock.
Bob K.

[simonjeff1]

hotshott,
For the first question, go to:http://www.nmra.org/ and review the "Standards and RPs" section (link on the left-hand side down the page a bit. This should tell you everything you needed to know, and then some, about radius, clearances, and everything else.

For the second question, ESU (LokSound) makes one for you, part #72446. I have used some of these decoders for my engines, and they are small, well made, and sound great. Plus, they are easy to install as they come with the speaker included and attached. If you go to:http://www.loksound.com/ you can listen to it. Look for the v3.5 sound files, American section.

Hope this helps.
Jeff

[Anonymous]

Hi all, im big into amtrak modeling but am limited to 28" radius for now. I would like to add an inside track to the 28". What would a good radius be so that the 85' cars don't hit the next track over? Second, does anyone make a P42 sound decoder yet?

Thanks! [:D]