How about some prototypical looking wheelsets?

With all this talk about slower running locos and finer code 55 track how about some better looking wheels that don't cost an arm and a leg like NWSL? 28" 33" and 36" with a thinner tread and a dished face at a reasonable cost.

 

Isn't the NMRA currently considering standards in this area, something along the lines of fine-scale standards. And wouldn't this mean a reduction in the tolerances in the manufacturring of track and turnouts thus another increase in cost. The wide tread on the wheels is needed to allow for these current tolerances.

 

<blockquote>quote:</font><hr>Originally posted by squirrelkinns:
Isn't the NMRA currently considering standards in this area, something along the lines of fine-scale standards. And wouldn't this mean a reduction in the tolerances in the manufacturring of track and turnouts thus another increase in cost. The wide tread on the wheels is needed to allow for these current tolerances.<hr></blockquote>

NWSL already makes wheels in different tread widths that work fine on standard track.

Reduced flanges would also make a new line of wheels more prototypical

 

I havent heard of the NMRA doing anything about the wheel size and all, and doubt that they are.

And no, with smaller wheel threads everything would still run fine on the current track guage. It would mean that your track would all have to be properly maintained and guaged, but thats no biggie. And with smaller wheel threads, the tolerences would actually increase. Place any wheelset (except for a NWSL) on a piece of track and move it around left and right. You'll see just about all the wheelsets are actually narrow in guage and move around, especially locomotive wheels, and thats because they have large threads. With smaller threads, the wheels would have to run like the real thing, with the flanges constantly riding on the rail, and so everything would run smoother (if your track was well laid). This whole thing is how it is because back in the 70s THEN the tolerences were really low, so they had to enlarge everything to make sure it ran. Its a "sort of" Catch-22.

Mike

 

I'm not a railroad employee but I agree with Alan's comments.
If wheel flanges were in constant contact the railroad repair shops would certainly be kept busy and we would need flange lubricators even on straight track.

 

That is also where 'super-elevation' on curves comes into play, when done right the flanges do not touch then either.
Looking into this even further, yes the smaller tread does track well enough on tangent and curves the real problem is at the frog and its safety rails, you'll definitely need to reduce the distance of the gap between the outside stock-rail and the safety-rail also you'll have to look into reducing the flange clearance in the bottom of the frog itself.(wasn't there a Canadian ferm that offered photo-etched frogs with the proper flange depth for hand laying code-forty turnouts.)

 

Yes, Athabasca Scale Models, except John (the owner) retired. At first he dropped his entire line and just made parts for a brass HO 2-10-2, but he just recently sold off the company so maybe all the parts will reproduced. The problem however with the etchings he made was that they were brass, not nickel silver or at least stainless steel. BTW, does anyone know exactally why our track is made from NK, and not any other metal that maybe doesnt oxidize that much or have better electrical conductivity?

Mike

 

<blockquote>quote:</font><hr>Originally posted by atirns:
The problem however with the etchings he made was that they were brass, not nickel silver or at least stainless steel. BTW, does anyone know exactally why our track is made from NK, and not any other metal that maybe doesnt oxidize that much or have better electrical conductivity?

Mike<hr></blockquote>

Way back in the prehistoric days of N and HO scale track was made of Brass and the ties were a fiber product. Staples held the track to the fiber ties. Then came plastic ties but we still had Brass rail. The problem with brass was when it oxidized the oxide coating was non conductive. So you either had to run your trains constantly or clean track constantly. Then came what was called nickel silver. It also oxidized but its oxide was electrically conductive. According to my old High school chemistry book all metals but one, oxidize. That is, they rust. They don't all look like iron oxide (rusty brown) But all metals except one,including aluminum, oxidize. Nickel silver was chosen because it had the best properties for use as rail including cost, ductility, conductivity, strength, availability and a host of others. Plus it didn't have the yellowish color of brass but rather the silver color of polished steel rail. Now you can find other metals that will conduct electricity better(like copper, silver, gold) but how much do you want to pay for a piece of flex track? And do they have the other qualities needed for track? Now I think Bachmann or Model Power used stainless steel in HO track and it is used in O guage and maybe G scale but I don't think it was used in N scale. Electrically, stainless steel has more resistance than nickel silver.

 

Squirrelkinns is correct about the super elevation aiding wheel tracking on curves to some extent, but that is on prototypically correct curves to scale. The taper turned on a wheel tire acts like a sewing thread spool. The spool will roll straight with both flanges, yet remove one flange and the spool will roll only in a circle. A taper like on a bottle cork does the same thing. The opposing tapers on a wheel set allow the set to "track" between the rails so long as any curve incountered does not exceed the maximum curving radius provided by the combined taper on the wheel set. That is to say, the smallest diameter on the one wheel to the largest diameter on the other wheel. The flange only comes into play when the wheel sets wear enough to negate the taper. Toy and model trains almost never run on prototypical track where the sharpest curve for HO would be no less than 54" radius including turnouts.

Real flanges are only one inch high and one inch wide. That would mean an N scale flange is only .006" wide and tall. With today's plastic solid non-flexing, non-sprung trucks, it would be impossible to lay track suffeciently flat and level to accomodate the "Scale" .006" flanges. HO flanges would only be .011", so not much better. You would also have to run at scale speeds, and the equipment would have to weigh all the lead you could stuff into it, and even then it wouldn't be enough.

You say your diesel engine weighs 200 tons in real life? that is 400,000 pounds. N scale is 160 to one, so that means your little diesel would have to weigh 2,500 pounds! Yes it would then stay on your track!

Inkaneer is also correct, and the reason NK is used is also because it can be soldered for electrical connection. It is not bad looking when oxidized, and the rail top looks like steel rails when cleaned, and has a tendency to 'heal' any wounds from nicks and scratches better than brass, and is a little stiffer if it has silver in it, or softer if it has tin replacing the silver. "Tinned Brass" we called White Brass.

Up until WWII nickle silver was called German Silver, and had up to 20% real silver, and various alloys of nickle in it, along with brass for malleable qualities.

Our rails today are part brass, and part tin in most cases, with neither nickle, nor any silver in it, either way it still solders OK. The difference being, the tin type coming from China is dirt cheap, while the silver type only available from Europe now, if at all, is more expensive than straight brass as we would expect. Its almost like fraud that both are sold as (pure) Nickle-Silver at the higher price as if it actually had real silver in it. There is a little difference in electrical resistance too. Silver is an excellent conductor, as is nickle! Most PC boards are made with a copper etch, then either gold, or nickle plated, never brass plated. Both nickle and silver corrode is conductive. Gold doesn't corrode.

I just remembered, my dad turned the flanges off of a pair of wheels years ago, and would roll that wheel set down his track to insure he had easments and curves elevated correctly. There was no flange needed because he had huge curves and the wheels tracked centering themselves in the rails. You could try it with a pair on an axle and see how good your track is.

[ 22 July 2001: Message edited by: watash ]</p>

 

Thanks guys for explaining about the wheels and also the why of nickel silver rails.

Mike