I'm always a bit nervous about turning off a thread that I have started for
fear that I might be making the last statement and then stopping any
responses. OTOH, it is time, I think, to get back to strictly frt cars.
So...let's terminate the wheel discussions by 11PM EDT tonight. We've pretty
much investigated the subject as far as frt cars are concerned. I'll
summarize a bit.

1. Frt car wheels are being made today with code 88 tire width. At least
some are being made with code 110 flange size. These wheels are referred to
by their manufacturer as Semi Scale wheels.

2. These wheels will operate very well on HO scale track and frogs built to
NMRA standard S-3 as long as the frog numbers are less than 10. Turnouts
with frog numbers above 8 will allow the wheel to drop into the gap between
the frog point and wing rail. This will not, necessarily, cause a derailment
but as the frog number increases past #10, the dangers of derailment will
increase. Emperical data will tell the story on derailments on number 10
frogs.

3. The thinner tread size of the Semi Scale wheels is much closer to
prototype appearances than the code 110 wheel tread and many STMFC members
strongly prefer it to code 110.

4. NMRA RP-3 and RP-4 "Fine Scale" track/wheel relationships work well with
true code 88 wheels.

5. Any wheel size will operate best on track frogs built to match the wheel
size...whatever it is. Thus, using wheels of more than one code...say, true
88 and 110, on the same track invites problems. The Semi Scale wheel is a
possible answer since it employs the code 110 flange. It is, however, what
we in the software world might term a "kluge".

Anyone with additional comments on this summary are certainly welcome to add
them...until 11 PM.

Mike Brock
STMFC Owner

Blithely ignoring Mike's

So...let's terminate the wheel discussions by 11PM EDT tonight.

I wanna pick a bone about his summary statement (in both senses of the word
"summary")

2. These wheels will operate very well on HO scale track and frogs built

to

NMRA standard S-3 as long as the frog numbers are less than 10. Turnouts
with frog numbers above 8 will allow the wheel to drop into the gap

between

the frog point and wing rail. This will not, necessarily, cause a

derailment

but as the frog number increases past #10, the dangers of derailment will
increase. Emperical data will tell the story on derailments on number 10
frogs.

As I said, Mike, Tim and I have operated trains with 088 wheels all around
the North Shore Club layout, Tim more than me, and Tim with more 088
equipped cars than I have (or than I own yet) where we have many switches >
No 8, and we have no problems.

5. Any wheel size will operate best on track frogs built to match the

wheel

size...whatever it is. Thus, using wheels of more than one code...say,

true

88 and 110, on the same track invites problems.

This happens all the time in our case, again, no problems.

Anyone with additional comments on this summary are certainly welcome to

add

them...until 11 PM.

Hey, cut me some slack, I didn't even get on line until about 10:30!

SGL

Not wanting to let a misunderstanding to remain misunderstood and, gulp!, I guess I will have the last word on this topic, let me quickly respond to Schuyler and Denny:

Schuyler says:

"As I said, Mike, Tim and I have operated trains with 088 wheels all around
the North Shore Club layout, Tim more than me, and Tim with more 088
equipped cars than I have (or than I own yet) where we have many switches >
No 8, and we have no problems."

With small numbered frogs like number 8's <g>, I don't expect any problems. I would note, however...again...if those wheels are Intermountain or Reboxx, they are probably not code 88 but are more likely "semi scale" with code 88 tire width and code 110 flanges. I don't know why this seems so difficult to understand.

Denny says:

"On the common "test" route on my layout, my test train with a
majority of cars (about 30 of mixed parentage) with .088" wheels, the
train will traverse two curved 83 #12's and four 83 #10s."

Now this is a much better test. Again, given that Denny says Reboxx, I believe these are probably Semi Scale wheels and not code 88...meaning that while the tire width is .088", the flange is code 110 0.030".

To be sure, I have not run extensive tests and let be very clear...I thought I had...that I do not claim that derailments will occur. I only have said that the wheels will drop into the gap on mainline sized frogs of number 10 or greater. Those that use industrial sidings will be safe <g> from this anomaly. Time will tell. IOW, when I have a piece of trackage out of guage or with some other problem, this does not guarantee a derailment. As a wheel clunks through some irregular joint or some such problem, it only warns of a possible problem which will then rise to the surface, say, during an op session or Prototype Rails. It is best to avoid these issues. As to whether or not the wheel dropping is such a warning, I don't know yet. Denny seems to have more data than anyone else and he seems satisfied. I would only say that, while thinner wheel treads do look much better, wheels dropping into gaps on turnouts don't. This dropping might have one advantageous side effect, however. If you've spent much time near real RRs...as I have...you'll note the clanging when a wheel strikes the frog. Maybe the dropping wheel clink can replicate that. I'll admit to actually filing down a wheel...making it a "flat" wheel to get the bang, bang sound as it moves along the track. This works well when the car is by itself, but the sound of a full train seems to drown it out.

At some point, Denny or I or someone with mainline sized turnouts need to test a fine scale wheel...true code 88 I believe. I have a set here and I'll try to test it. For whatever that's worth.

If I've said anything that Schuyler or Denny disagrees with, contact me off group and I'll set it straight. I don't think we should continue boring folks and wearing out their delete keys on this subject.

Mike Brock

At some point, Denny or I or someone with mainline sized turnouts need to test a fine scale wheel...true code 88 I believe. I have a set here and I'll try to test it. For whatever that's worth.

Who makes a true "Code 88" wheel, Mike?


Tim O'Connor <timboconnor@...> -->> NOTE EMAIL CHANGE <<--
Sterling, Massachusetts

Tim O'Connor asks:

Who makes a true "Code 88" wheel, Mike?
I think the NWSL fine scale wheel may be. I have one somewhere.

Mike Brock

The problem was not the hoppers. It was the hard chrome plating on the
driver's tires! After that was machined off, with no other changes to
the loco, the results were as mentioned with the same cars and wheels.
At that point in time, the only semi-scale wheels available were some
NWSL Code 72 and CV "Fine Scale" if you had a hoard put away.

Max

Max, you missed the point. Reducing the TE necessary to haul the hoppers by
reducing both the starting force required, and the rolling friction once
moving, can have a significant effect on how many hoppers you can pull.
PART of the problem was the hopper TRUCKS. With replacement wheels

properly<< fitted to the truck frames (that is, with the appropriate

length of axle), the rolling resistance is dramatically reduced.

SGL
----- Original Message -----
From: "Kathe Robin" <kathe@...>
To: <STMFC@...>
Sent: Saturday, August 16, 2003 12:02 PM
Subject: Re: [STMFC] ADMIN: Wheels have rolled far enough

The problem was not the hoppers. It was the hard chrome plating on the
driver's tires! After that was machined off, with no other changes to
the loco, the results were as mentioned with the same cars and wheels.
At that point in time, the only semi-scale wheels available were some
NWSL Code 72 and CV "Fine Scale" if you had a hoard put away.

Max


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