Fast Tracks

I have #6 and #8 double crossover kits ordered. These are for code 83 Micro Engineering rail. My question is: will ME code 70 work in these fixtures at all, or will the results be unusable? Also, what is the width, in .000" of the rail base on these two sizes? If the code 70 will not work in these fixtures I probably will want to order just the double crossover fixture at a later date. The point forming and frog point grinding tools should work for both, right?

Thanks

Hi,

The critical dimensions of code 70 and code 83 rail are close enough that they can successfully be used in the same fixture, as long as it is Micro Engineering rail that you are using, rail from other manufacturers are not as close.

Code 70 rail has a base width of .070" and the head is .030"
Code 83 rail has a base width of .067" and the head is .032"

It might seem odd that code 83 is actually narrower than code 70, but it is. Micro Engineering code 83 rail made prior to 1998 was wider at the base than code 70. That year, a German manufacturer was going to "resurrect" TT scale trains, and ordered from Mircro Engineering almost a million liner feet of code 83 rail, that they were going to use in their TT scale flex track, but they required the narrower base. ME had a custom run of this rail made for them, and then the German manufacturer went bankrupt....

So ME was stuck with a lot of code 83 rail, and new dies to match. At that point they decided that this would be their new standard size for code 83.

I got this story from a conversation with Bob Rand, the owner of Micro Engineering a couple of years ago after a few fixtures were sent back from customers using old code 83 rail. We now offer two versions of code 83 fixtures, but usually recommend people purchase some newer code 83 rail for turnout construction, and keep the older stuff, if they have it, for other areas of the layout.

_________________
Cheers!

Tim Warris
Fast Tracks
http://www.fast-tracks.net
service@fast-tracks.net

Thanks for the information. It is very helpful. I plan on using ME rail almost exclusively, except for what I have on hand of others. After I am comfortable with building turnouts and crossovers I probably will order the other sizes of kits, spread out over time.

Does it work both ways as far as being able to interchange ME code 83 and 70 rail?

Does 70 work in a 83 jig and 83 work in a 70 jig?

YES. Order the code 70 fixtures - you can then use ME c70 or c83 rail, also the LaVancil c81 (from CV, R-O-W, and P87 Stores), as well as the C&L c75 (from P87 Stores) steel rail. The base widths, and rail head widths allow for interchange in the fixture and resulting in correct gaging. Double check the guardrail track check dimensions with a track gage for superior reliability when using any size other than the initial c70.

_________________
-ed mccamey-
COSLAR RR - http://www.coslar.us/
NMRA Standards and Conformance Department
PROTO & FINE Scale Coordinator
I estimate I have about 5 pounds of coupler springs somewhere in the vicinity of my workbench.

Forgive me for being new at this and also for probably re-asking questions on a settled topic.

I am planning to build a layout using both code 70 and 83 rail. I see the on the KB that they can both be used in both code 83 and code 70 fixtures (https://www.handlaidtrack.com/kb_results.asp?ID=124). I also see references to Micro Engineering rail having changed in the past and note that these posts are over 10 years old. So, Questions:

Are the dimensions referenced here still accurate for current production ME rail?

That being true, assuming I have no fixtures to begin with, and assuming that that code 70 and code 83 fixtures are actually slightly different, is there a recommendation as to which fixture is preferable if one is going to build with both rail sizes. Specifically --

Would one or the other produce the least variation within NMRA specifications when used with the 'other' rail size?

Is the variation different in one case or the other - i.e. one out of the middle of the specification wide, the other narrow?

Is there a difference in the actual build i.e. is one more difficult with the 'other' rail size?

In short, would it be best to purchase code 70 or 83 fixtures?

Hello wisfarmer,

As the operator who makes all of the assembly fixtures that we sell I can assure you that code 83 and code 70 fixtures are cut with the same mill bit. The only difference between the two is the lettering. In retrospect, if Micro Engineering rail been the same as it is today then the fixtures would have been labeled Code 70/83 for ME rail. The same does not apply to rail made by other manufacturers such as Atlas and Peco.

FYI, the base width for Micro Engineering code 70 rail is actually .002" wider than their code 83 rail. This difference is insignificant when using our tools.

_________________
- Terry -
Customer Service - Fast Tracks HobbyWorks Inc.
service@fast-tracks.net

Perfect. I suspected so but because they are listed separately, I wasn't sure. Thanks for the very fast response.