MT Metal Wheels

[peteski]

My order at the BLW for a set of these wheels has been canceled (sold out). So it looks like ether MTL didn't make many of these, or they are very popular with modelers.

[Point353]

My order at the BLW for a set of these wheels has been canceled (sold out). So it looks like ether MTL didn't make many of these, or they are very popular with modelers.

Joe from MTL did mention that initial demand was strong and that the first production run had sold out quickly.

You might check with this dealer for availability:
http://www.tophobbytrains.com/0031202033MetalWheels-12-axlepack.aspx
http://www.tophobbytrains.com/0031202133metalwheels60-axlepack403-60-nscale.aspx

[peteski]

Joe from MTL did mention that initial demand was strong and that the first production run had sold out quickly.

You might check with this dealer for availability:
http://www.tophobbytrains.com/0031202033MetalWheels-12-axlepack.aspx
http://www.tophobbytrains.com/0031202133metalwheels60-axlepack403-60-nscale.aspx

Thanks, I wasn't really all that gung-ho to get some of those wheels. I just happened to be placing an order with BLW for other items, so I just added a 12-pack of the MTL wheels.  I'll get a set at some point in the future when I place another larger order with one of the online vendors I usually deal with (MBK or BLW).

[mmagliaro]

This isn't to add to the metal wheel discussion but is something I recently discovered with the plastic wheels and this reply was triggered by Max's post with dimensions.  The flange width dimension that you measured on the plastic wheels (.010") must be from an older set as I recently discovered something that may be old news to many of you with decades at this but I sure didn't know and had never heard of. 

I had a number of various vintage older hoppers that I hadn't run until very recently.  Some had the larger flanges and I changed them to low profile while others already had the low profile.  All were original with truck mounted couplers.  What happened was a problem when backing through switches with a string of 10 to maybe twenty-five cars I had a few that would pick a switch on occasion.  And it was always the same cars and from the same sets.  A quick glance and a quick back gauge check showed them all to be fine, in spec.  A close look at the switch and it looked to be fine.  Maybe a little tweeking could be done but basically should have worked and DID on a LOT of different cars. 

This had just shown itself with these hoppers.  As I was looking closer at them I noticed that the flanges on the troublesome cars, those that already had the low profile flanges therefore hadn't received new wheels, did appear to be pointier, narrower, maybe.   Measured and sure enough, .010" whereas all of the replacement sets I had and all of those I measured on any other cars I had were .020".  It was all one series of cars.  I changed them all out with new plastic wheel sets (.020") and no more problems.  Then I remembered that some time ago I had a few boxcars (5?) that had done this once in a while, always the same ones, and I had just set them aside to be looked over another day.  Went and checked them and sure enough, those had the .010" flange widths.  That had me checking through a lot more and only found another few cars in my inventory with these narrow flanges and replacing them cured any propensity for picking a switch.

Bottom line, the newer plastic MT wheel flange width measures .020" which also agrees with the NMRA spec.  I suspect with the knowledge floating around here that somebody can chime in with a fuller explanation.  Hopefully it's helpful to someone like me who never knew this was a possibility.

I was aware that plastic MT wheel flange widths had gotten away from the razor-thin style of the old pizza cutters to a wider profile, but I never kept track of just how wide they got and when.  It is interesting to note that Fox Valley wheelsets have .020" wide flanges, and I have always found them to be much more sure-footed going through switch points.  They have a better profile with a rounded-over edge, not a knife edge, so they won't pick points.

The new MT metal wheelsets, however, seem to have a REALLY wide flange: .028".  They work fine on my layout, but I really think they should stick within the NMRA standards.   

[peteski]

The new MT metal wheelsets, however, seem to have a REALLY wide flange: .028".  They work fine on my layout, but I really think they should stick within the NMRA standards.

Since this is a brand new design (and NMRA specs have been around for a while) I wonder what made them not follow the recommended design but to "roll their own"?

[wcfn100]

The flange width for RP25 wheel contour is based on the code of the rail.  .028" would be for code 100 rail.


Jason

[peteski]

The flange width for RP25 wheel contour is based on the code of the rail.  .028" would be for code 100 rail.
Jason

Ah,I see. But  when was the last time we used code 100 in N scale?

[wcfn100]

Ah,I see. But  when was the last time we used code 100 in N scale?

Probably the last time I had a 9 3/4 radius everyone still designs for.

Jason

[peteski]

Probably the last time I had a 9 3/4 radius everyone still designs for.

Jason

The tallest N scale rail I recall (even the 7" Arnold hairpin curves) were less than code 100.  So are you saying that in the past N scale did use code 100?!

[Point353]

Probably the last time I had a 9 3/4 radius everyone still designs for.

The radius of the inside track on a standard T-TRAK corner module is just a shade over 11".
These look good to me: https://www.therailwire.net/forum/index.php?topic=42469.msg535475#msg535475

[Doug G.]

No N scale manufacturer has ever used code 100 rail. Code 80 is the tallest.

Doug

[nkalanaga]

Peteski:  The wheels stayed on my "axle" for turning mostly because I used very light pressure.  No need to press the file against the flange to hard, because I didn't want to remove the whole flange.  I very light, brief touch, check the results visually, then either take another cut, or get the gauge out.

As for the short-lived MT lo-pros with very narrow flanges, the problem I found wasn't the flanges per se, but the gauge.  When they narrowed the flange, they left the back-to-back distance the same, which narrowed the check gauge.  With one flange against the rail, the other could hit points and guard rails.

[narrowminded]

As for the short-lived MT lo-pros with very narrow flanges, the problem I found wasn't the flanges per se, but the gauge.  When they narrowed the flange, they left the back-to-back distance the same, which narrowed the check gauge.  With one flange against the rail, the other could hit points and guard rails.

You made me take them out and measure a little.   That's it, I'm sure.  They seem to measure about .308" back to back at the flange and the S-4.2 standard has a max of .303" and a min of .297".  Then when you go to the track standard S-3.2 and find that the flangeway target is .028" with a max of .030" and a min of .027" you see it.  But that also raises the issue of the mentioned new metal wheel flange thickness measurement of .028" and if true, that's likely to be trouble or at least very finicky as it consumes all tolerance and even .001" tight if the flangeway was at the minimum.  Leaves no room for tolerance in the trackwork OR the wheel gauging.  A review of those two NMRA specs will show this and more.  The radius at the wheel flange perimeter may allow a car to get through without derailing but it would cause some bumping, rocking and rolling.  I had that problem with #5 turnouts that weren't in spec when I purchased the Seaboard 2.0.

I had #5 Atlas switches that were over the wing/ guard span spec (dim "S" in the track standard S-3.2) by more than a little and as part of that had the flangeways or guard rail clearances at less than spec, some as narrow as  .017" which, as you might imagine with cars with proper .020" wide flanges, had cars bumping or rocking through those turnouts, some worse than others depending on where their tolerances fell in the scheme of things.  I didn't start with the turnouts being suspect but after thorough inspection and careful regauging of the wheels per spec (plastics in spec but also not adjustable), recognizing the effects of the tolerance, it led me to the track standards and a very logical result but also a huge surprise.  I really didn't expect that and not the numbers of switches that had at least one problem, several with more than one problem, and several at the extreme right of the yard that had multiple problems on the same turnout  adding up to pretty severe, and would bind the wheels or cause some locos to derail.  Most still passed cars through without derailing but there was an inordinate amount of rocking or bumping on those switches with troubles, some worse than others depending on where in the spec tolerance they fell.  After grinding one side of a flat file to both thin it sufficiently to fit in the flangeways and also to make it cut on one side only, as needed, I was able to clean everything up, get it in spec, and now trains just glide through, minimum if any rocking and rolling, no derailments.  At least not until this wheel thing that I had no idea about surfaced.  I'll write it off to another new thing I learned that I never wanted to know.

Edit add:  A spotting clue on those wheels without measuring is a noticeable bulge on the wheel backside from the axle out, ending near the flange outer diameter.

[nkalanaga]

My experience with the narrow-flange MT wheels was very short lived.  At the 2008 N scale convention I bought an IM 60 ft flatcar, the first car I'd bought in a few years with MT trucks.  Since I had a large supply of Precision Masters wheels, and quite a few original MT lo-pros, I also hadn't bought any new wheels in some time.  I took that car home, put it on the track, and it wouldn't run through my dual gauge turnouts.  Thinking that the MT wheels had to be right, I checked the turnouts, and they were fine.  Everything else ran fine.  Finally I checked the new wheels, and the problem was clear.  I never tried running another set, since the flanges were sharp enough to feel the difference, and simply felt any new MT wheels that came along.  If they felt sharp, they were discarded, no questions asked.

[Philip H]

So, 73 replies in, whats the consensus?