Binding track?

I have what is probably a track problem that I don't know how to solve. Most of my steam locomotives run fast of the straightaways and slow
significantly on the curves. Track voltage is consistant all the way around so I'm thinking that there is some binding on the curves. I don't have room to make the curves any wider so does anyone have any suggestions?
Carter
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Carter Braxton wrote:

Well Carter, What you are seeing is "Physics in action".
It takes more power (effort) for the train to traverse curves than it does straight track. The sharper the curve, the more noticeable the effect.
So, no, there isn't anything wrong (easily fixable), More power (voltage available on the track) will bring the speed back up, but YOU have to be at the controls turning up the power (And slowing things back down once the curve is past).
Chuck Davis
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I think that the NMRA standards for HO gauge is around 0.640 minimum to about 0.670 maximum, with a wider gauge recommended on curves. I made a brass gauge gauge :-) that mikes out to something like 0.643 on one end and 0.672 on the other. I had a section that was too narrow, possibly from a habit of laying my automotive drop light on the rails for a couple of minutes when doing something tiny on the layout that needs two hands. I think I softened the plastic ties and it narrowed the gauge. You could actually look head on at the oncoming loco and see it ride up on one side for a second or two. Anyway, I later deliberately appied the drop light heat for a couple of minutes, then angled the gauge in and twisted it perpendicular to the rail and let everything cool for an hour. Presto!! It was fixed. BTW, I once melted / deformed about 10 ties in a row leaving the light lay there too long, and had to remove and replace that section of ties. It was kind of fun drilling the little holes and applying the spikes on the new ties.
You could try my method, or replace one rail on the curve, making the gauge a little looser. Is this a steam engine you are having this problem with? Are the middle drivers blind?
Wayne
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*snip*
If you don't want (or have the machining skills) to make a track gauge of your own, your local hobby shop should carry NMRA standards gauges. They're about $12 in my area now, but they're an essential purchase. They do more than just track, too.
Puckdropper
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How about some dimensional units associated with those numbers.... huh?
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Mark Mathu spake thus:

Microfurlongs?
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of use of the word "fuck" is incapable of writing a good summary
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On Fri, 04 May 2007 22:49:31 -0700, David Nebenzahl wrote:

MicroFurlows? Little teeny Porters with stereotyped Mexican crew?
--
Steve

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Dear Mark, David and Steve.........my apologies for the confusion. I didn't realize that you all attended government school. These things are supposed to be intuitive for males.
Anyway, my rememberances about the HO gauges are in inches, but they were wrong. The Official NMRA Standard 3.2 numbers are.........drum roll......... http://www.nmra.org/standards/S-3_2ScaleTrackwork.html 0.649 inches for straight track (tangents) 0.672 inches maximum, with thoughts about widening the gauge on curves discussed in NMRA Recommended Practices 8 http://www.nmra.org/standards/rp-8.html For my railroad pals living in other countries, like Hoboken and Utah, that works out to be 16.4757 millimeters for tangents 17.059 millimeters max
81.9 Microfurlongs for tangents 84.8 Microfurlongs max
Some figures rounded, some figures truncated, all figures subject to change without notice.

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BTW Carter, Charles was correct too. Railroad wheels have no differential, so on curves one wheel or the other on each axel is going to be sliding on the rail a little. Plus there is a lot of scrapping of the outer wheel flange on the inside of the rail head too, all combining to add drag and produce those lovely echoing "chalk on a blackboard" "my teeth are cracking" harmonies heard while traversing tight curves on the subway.
Wayne
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Wayne L wrote:

There is a differential effect through the wheel treads being coned. The wheel diameter beside the flange is larger than the wheel diameter at the outer edge. On straight track the wheels/axle should centre itself on the rails so causing the wheels to sit on points of the same diameter and on curves the wheelsets move across so that the outer wheel will ride near the flange while the inner wheel will ride near the tread outer edge.
There probably isn't enough coning to accomodate 15" curves. =8^(

That noise comes from the flanges touching the rail at an angle. (although I believe that some US suburban lines don't have coned wheels(?))
Regards, Greg.P.
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Well I never thought of that Greg. Brilliant those 19th century RR mechanical engineers, and you're pretty sharp too !

So on really tight curves the flanges can rub against the inside of the outside railhead in front of and/or behind the axle center line ?
Between you and Professor GP, I'll be and expert too if I live long enough :-)
The Professor turned me on to the Yahoo EarlyRail group. I didn't know there was such a group 2 months ago. The era interests me most, but I actually like all aspects of the hobby.
BTW, we've had a day here and there in the 70s. Is there an ocassional chill in the air where you are?
Wayne

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Wayne L wrote:

I never should have left the 19th century!

Well, you'd be pushing your luck if you try to run anything around that sharp a curve - something like an HO 2-10-0 on a 15" radius!!! =8^O

I've already booked a second life so I can finish all the projects I've started - haven't had confirmation as yet!

Well, the thermometer got down to about 50 degrees F overnight - winter's really setting in!

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