It there a way to identify Marx O34 track, absent holding a piece up to an O27 curve, or assembling a circle of it and measuring the diameter? Also, am I correct in assuming that you would still need a straight inserted in order to keep concentric ovals of O27 and O34 evenly spaced? Thanks.
Marx 034 curves have 5 ties on them instead of 3. Not sure about adding straight sections that you asked about.
You don’t need to make a circle. Just measure, in a straight line, the distance between the ends of the center rail of a curved section, ignoring any pin. That distance should be about 12 1/16 inches.
Yes, but you would have to use an O34 straight, which is longer than an O27 straight, in the outer oval. The center-to-center distance between the tracks would be 3 1/4 inches, which is enough for straight tracks but may be too close for curves, depending on what you’re running.
(You’re not the Gregory Nagy that I went to school with in Indiana, are you?)
As stated the o34 sections have 5 ties per section (all of them I have ever seen were black) and I believe the straights had 5 ties per section as well. The straights were longer; about 12 to 14 inches IIRC. Marx also made a 90 degree crossing for o34 I think. I just use regular straights with mine and cut to length.
Hope this helps.
J White
Marx O34 straights are about 11 1/8 inches long. The rail web has a distinctive knurling, the rail flanges are folded under the rail, and the Marx track pins have a dull finish and are of constant diameter. Lionel and K-Line rail webs are smooth, the rail flanges are folded up, and the track pins are usually shiny, with a substantial notch in each half of the pin.
Here is a little trick that I used to make a compact double crossover in a corner of my layout, using O34 and O27 track:
Imagine three different corners:
o An outside track has an O27 straight section, then an O34 curved section, then a tiny 9/16-inch straight section, then another O34 curved section, than another O27 straight section.
o Another version of the outside track has an O27 curved section, then two O27 straight sections, then another O27 curved section.
o An inside track has two O27 curved sections.
Lay all three of these on top of each other with the inside and outside tracks going into the corner, 6 1/4 inches apart, to see where to replace the O27 curves and straights with four O27 turnouts.
Thank you. The “5 ties” was the type of description I was looking for, so as to spot them in a photo or at a train show where I might not have a ruler. Also, aside from a short time at Tulane, all of my schooling took place in the commonwealth of Pennsylvania. Thank you for the replies, everyone.