Tim O'Connor observes:

I have run .088 wheels on a large club layout with hand-laid
track up to 20 years old, with no problems. However, I don't
think there are any #10 turnouts. But there are some tricky
curved turnouts that are worse!

Sure there are, Tim. I laid some of those, and I know they are No 10 or
larger. And on the new section, when I did the CAD layout of the tracks, I
used No's 5-12. You are right, however, about the curved turnouts.

SGL

Jack Wyatt says:

This is where I'm not following you. I don't think wing rails support
anything. Their function is to guide the wheel to the correct side of the
point of the frog.

They actually have at least two functions. Even the prototype. To quote from
the Track and Structure Cyc of 1955: "The wing rails, in common with the
point, serve to carry the wheel treads through a distance back of the point
of frog and also act as guards for the flanges". In this case, "back" refers
to the distance between frog point and the moving points. If you look at a
drawing of an actual frog, you'll see that the larger the frog number, the
more use a wheel will make of the wing rail for support.

Mike Brock>

On Apr 1, 2:30pm, Jack Wyatt wrote:

Subject: Re: [STMFC] STMFC RP-25 award to Roger Miener

But with standard
NMRA trackwork, the 0.110 wheels drop, too. The 0.088 wheels just drop
slightly further and a little bit longer.

Exactly. Mike was concerned with wheels "dropping" into the gap. Fact
is, any wheel has to drop when there's a gap. The real question is "how
far does it drop" versus "how much drop is acceptable?"


As it turns out, these questions are moot (from Mike's perspective), as I
just phoned him and he has "seen the Light" and is feverishly converting
all of his brass steamers to Proto:87. I understand he already has 5
axles of his 4-12-2 completed.

Regards,

-Jeff

--
Jeff Aley jaley@...
DPG Chipsets Product Engineering
Intel Corporation, Folsom, CA
(916) 356-3533

<<Well...that could be...and it might not be. It simply depends on how far
the
wheel has to roll off of a frog's support looking for support from the wing
rail. If it finds it before it drops...great. If it doesn't...kerplop. The
wider the wheel tread the quicker it will find support....

Mike Brock >>

OK, I see what you are talking about - the wheel riding up on the wing rail
from the other route. The wider tread will do it sooner and the shallower
the angle of the frog, the bigger the gap to contend with. But with standard
NMRA trackwork, the 0.110 wheels drop, too. The 0.088 wheels just drop
slightly further and a little bit longer. I don't think that would increase
the derailment potential very much, but probably adds to the clickity-clack
factor.

Jack Wyatt

<<Well...that could be...and it might not be. It simply depends on how far
the
wheel has to roll off of a frog's support looking for support from the wing
rail....

Mike Brock>>

Mike,

This is where I'm not following you. I don't think wing rails support
anything. Their function is to guide the wheel to the correct side of the
point of the frog.

Jack

Mike,

In the way I understand the NMRA HO track standards, the distance between
the wing rail and rail is 0.050 inches, so a 0.088 wheel will not drop until
it gets to the gap in the frog. But a 0.110 wheel will drop at least 0.003",
or maybe more (minimum depth of flangeway is 0.028" - flange on 0.110 wheel
is 0.025"). The 0.088 inch wheel only drops 0.002" futher (0.023 flange
depth). I don't see what the big deal is about 0.002". Or is the problem
that some commercial turnouts have non-standard dimensions?

Jack Wyatt

Tim O'Connor writes:

I have run .088 wheels on a large club layout with hand-laid
track up to 20 years old, with no problems.

Keep in mind that the only issue has to do with gaps at frogs. There is
nothing whatever wrong with in gauge code anything running on in gauge track
itself. And, ME or handlaid [ in gauge ] should not pose any problems.

However, I don't

think there are any #10 turnouts. But there are some tricky
curved turnouts that are worse!

Well...that could be...and it might not be. It simply depends on how far the
wheel has to roll off of a frog's support looking for support from the wing
rail. If it finds it before it drops...great. If it doesn't...kerplop. The
wider the wheel tread the quicker it will find support. Again...that doesn't
mean a code 88 or any other code wheel won't operate well through turnouts.
It does mean that a code XX wheel needs to operate on turnouts designed for
the wheel's code. NMRA track standard S-3 provides that only for code 110
wheels. The problem only becomes severe on larger numbered frogs...showing
up on number 8s and becoming noticably a problem on number 10s.

Mike Brock

Jack Wyatt comments:

I hate to keep bringing up the .088 wheels, but it's been on my mind

lately.

Nothing wrong with the topic.

Mike, I appreciate the theory, though I having a bit of trouble following
exactly what happens in the frogs. As a practical matter for the people

that

are actually using the .088 wheels, are you having any problems?

Since I'm not currently "using" any, I can't give a good answer. I have
tested some.

Mike Brock

<<Any code 88 wheel will tend to fall into the gap between frog and wing
rail
when rolling on a turnout built to the current NMRA S-3 track standard...

Mike Brock>>

I hate to keep bringing up the .088 wheels, but it's been on my mind lately.
Mike, I appreciate the theory, though I having a bit of trouble following
exactly what happens in the frogs. As a practical matter for the people that
are actually using the .088 wheels, are you having any problems?

Also, if I don't go with the .088 profile using Reboxx wheelsets with
various axle lenghts, what .110 profile replacement wheels are modelers
favoring nowadays?

I appreciate any help with these questions.

Jack Wyatt

I have run .088 wheels on a large club layout with hand-laid
track up to 20 years old, with no problems. However, I don't
think there are any #10 turnouts. But there are some tricky
curved turnouts that are worse!

At 12:50 PM 4/1/02 -0500, you wrote:

<<Any code 88 wheel will tend to fall into the gap between frog and wing
rail
when rolling on a turnout built to the current NMRA S-3 track standard...

Mike Brock>>

I hate to keep bringing up the .088 wheels, but it's been on my mind lately.
Mike, I appreciate the theory, though I having a bit of trouble following
exactly what happens in the frogs. As a practical matter for the people that
are actually using the .088 wheels, are you having any problems?

Also, if I don't go with the .088 profile using Reboxx wheelsets with
various axle lenghts, what .110 profile replacement wheels are modelers
favoring nowadays?

I appreciate any help with these questions.

Jack Wyatt

Tim O'Connor <timoconnor@...> *** NEW EMAIL ADDRESS ***
Sterling, Massachusetts

Jack Wyatt asks:

So, are the Reboxx's a true code 88 or a hybrid? If I use Reboxx's, are my
wheels going to fall into the flangeways on #10 and higher turnouts?

Any code 88 wheel will tend to fall into the gap between frog and wing rail
when rolling on a turnout built to the current NMRA S-3 track standard. A
code 88 wheel with flange WIDTH of a code 110 wheel will not find the
surface of the wing rail because its tread width is not great enough to
reach it before dropping. Will it derail? Not necessarily. Bad track will
not always cause a derailment. It, however, certainly doesn't help to keep
stuff on the track. For a code 88 wheel to not drop into the gap, the
wheel's flange width should be less than a code 110 wheel's AND the
turnout's flangeway WIDTH should be less so that the wheel's smaller tread
can reach the wing rail. The only thing flange depth has to do with it is if
the modeler chooses to build a "kluge" [ a method of solving the problem
using a different process from original design....it working sometimes] by
letting the wheel be supported by its flange. One has to have pretty damn
accurate flangeway depths for that but it IS a way out.

Mike Brock

As NWSL (US), IM, and Reboxx (China) have the wheels turned they could
have the correct maximum flange depth which (from memory) is .023 on a code
88 wheel. I'm with Richard in that for semi-scale/or RP-25 we don't need
equalized trucks. For full scale it might very well be different. Notice
that NWSL, IM, and Rebox do not call there wheels RP-25's, they call them
"semi-scale".
For now we need to be happy with what we get and continue to educate. I
think I know all the people that are interested in this sort of thing and if
another is invited to the discussions one only gets a blank stare! Someday,
remember it wasn't to many years ago if you asked for a .088 wheel all you
got is a blank stare<VBG>.

Jon Miller
AT&SF
For me time has stopped in 1941
Digitrax DCC owner, Chief system
NMRA Life member #2623
Member SFRH&MS

<< ... Perhaps the current code 88 wheel...the one I examined
anyhow...should be
called a code 88/110 wheel. Nah.

Mike Brock>>

So, are the Reboxx's a true code 88 or a hybrid? If I use Reboxx's, are my
wheels going to fall into the flangeways on #10 and higher turnouts?

Jack Wyatt

Bill Schneider notes:

There may be more to it than that.... that old money thing. The typical

wheel mold has the parting line (the division between its two halves) on the
lip of the wheel flange. Those cheap manufacturers, being the penny-pinchers
thay are and not giving a damn about the advancement of the hobby, could
create a "code 88" wheel by simply tooling a new insert to make the wheel
tread using the existing back half of the wheel mold, thus saving a few
thousand of those green paper things..... :>)

Actually, if a true code 88 wheel were to be made...and I'm not saying one
hasn't been, I've only examined one...it might require matching trackwork at
the frog. IOW, the flangeway might need to match for acceptable operation.
So, perhaps manufacturers putting code 88 treads on code 110 wheels have
done us a favor...unless you have higher numbered frogs and don't like
hearing the wheel bang into the point of the frog. True code 88 wheel
matching track flangeways are not relevent to anyone using code 110 RP-25
equipped engines, though...particularly those with significant wheel
bases...because "we" are going to stay with flangeways matching code 110
wheels...NMRA standard S-3. At least those of us not wishing to hear that
screeching and screaming sound.

Perhaps the current code 88 wheel...the one I examined anyhow...should be
called a code 88/110 wheel. Nah.

Mike Brock

Mike,

There may be more to it than that.... that old money thing. The typical wheel mold has the parting line (the division between its two halves) on the lip of the wheel flange. Those cheap manufacturers, being the penny-pinchers thay are and not giving a damn about the advancement of the hobby, could create a "code 88" wheel by simply tooling a new insert to make the wheel tread using the existing back half of the wheel mold, thus saving a few thousand of those green paper things..... :>)

Bill Schneider
Manufacturers...possibly wanting to avoid having their
customers avoid having to hear this wrenching and screaming sound...appear
to have merely placed a code 88 tread on a code 110 wheel

Roger Miener writes:

True, if you are using "steam roller" Code 110 - RP contour wheels
together with the NMRA track and wheel standards associated with same.

Roger hereby receives the very first STMFC "I understand NMRA RP-25" award.
This award has never been issued before for the simple reason that no one
has ever indicated...or expressed...true knowledge of RP-25. Note how
horribly Lionel Strang strangled it in his "wheels" write up in the April
MR...making no less than three errors in two sentences. Many times I've had
to tell people that there is more than one code [ read that, wheel size ]
covered by RP-25. All of this is abundantly clear in the RP...which is no
further away than the internet.

Probably still true if you refine the above and go with the
"semi-scale" Code 88 wheels.

I will note that I believe that at least some code 88 wheels do not conform
with Code 88 RP-25 but are simply code 110 wheels with a thinner tread. For
a true RP-25 code 88, the flange width and height should also differ. IOW,
if one were truly going to code 88 wheels...with the proper flange...the
flangeway width would be smaller to accomodate the smaller flange...thus
making it possible to smoothly roll a 2 axle code 88 wheeled truck through a
number 10 and larger frog designed for code 88 wheels without falling into
the gap between frog and wing rail. Of course, in that case the wrenching
and screaming sound you hear as a 4-12-2 with code 110 RP-25 drivers enters
the turnout is the sound of a certain amount of nickle silver being removed
from the guard rail of said turnout...and the cleaning of said 4-12-2's
driver sides. Manufacturers...possibly wanting to avoid having their
customers avoid having to hear this wrenching and screaming sound...appear
to have merely placed a code 88 tread on a code 110 wheel. I'm not sure how
a true code 88 wheel would negotiate a frog built to the S-3 track standard.
Perhaps the NMRA should produce track standards to match other wheel
sizes...assuming S-3 is designed for wheel standard S-4 which is pretty much
a code 110 RP-25 wheel size.

Mike Brock