Hand laid Fine N scale turn out standards / tools / solutions?

[craigolio1]

Hand laid Fine N Scale turnout standards / tools?

Hey all. Years ago I made a HUGE investment and converted all of my freight car wheels to Fox Valley wheel sets. This was long before I ever laid track or ran a train.

Well fast forward and I’ve laid some track and run some trains. I have a curved #10 hand-laid using Fastracks. The cars that have FVM wheels drop into the frog. Other brands of wheels don’t. Well wouldn’t you know, I bought the narrow treads.  The frog is so big and the tread just narrow enough that both wheels on a freight car truck are unsupported.

I tried shimming the bottom of the frog. Freights cars a glide through. Locos that I’ve had flanges turned down glide through. Some locos that are stock and still have low profile flanges …. But not THAT low profile….. bump over the shim.

I’m very invested in these wheel sets. They look great and cost $$$$. I’m right at the beginning of track laying (only three turnouts in) so I’m at a bit of a cross roads.

Shim and deal with the bump? I guess. But I’m $$$$ in to my trains and wheel sets so I’ll feel pissed off everytime a nice loco climbs the shim?

Keep turning down flanges on locos so they don’t climb the shims? Yeah. But the guy who used to do them for me doesn’t anymore and I have A LOT that need turning. Plus the “problem” is known and it’s not the flanges. So turning is a work around.

That leaves me with building turnouts to really tight clearances so the wheels can actually perform as a wheel should on a frog, and be supported the whole time it’s passing through.

So finally I get to my actual question which is… is there a fine N scale standard I can follow? What about templates and or tools to help me? Or am I just on my own to build them as I see fit?

Naturally I’m open to hearing of others experiences and solutions.

Thanks!

Craig.

[learmoia]

Are the FVM wheel flanges in gauge?... is the track in gauge?  Do you have an NMRA gauge? (I assume you do)...

Based on what you noted as the issue, it sounds like something is out of gauge. 

If you tightened the tolerances of the rail to satisfy the FVM wheels (tighten the gap between the frog and the rail so the FVM wheel can't all in, is everything else going to accept it?

But if everything is in gauge, there shouldn't be enough play between the rails and flanges to let the wheel tread slide over enough to fall between the rail and the frog.

[peteski]

To me the problem sounds like the wheel falls into the flangeway between when the wheel tread leaves the closure rail and  before it is supported by the center pointy part of the frog (I dont' know what the official name for that is).  It is like the frog's flangeways are too wide, so when wheel tread is not wide enough, it will fall into the flangeway.

[craigolio1]

This is exactly what’s happening.  The number ten frog is huge. The narrow tread wheel sets are unsupported and fall into the chasm in the middle.

I didn’t build this turnout (not that that matters). I bought it but it checked out with my NMRA gauge, or at least I felt like it did when I bought it maybe ten years ago. There’s lots more testing to do.

Wheels are in gauge. Track is in gauge. Regular wheel sets on MT, Atlas, etc traverse the frog just fine. It’s my belief that the narrow tread FVM wheels don’t necessarily follow the NMRA standard and require a finer build.

As far as tightening up the clearances go, yes it could cause issues with other equipment but I would take measurements of other wheels in my fleet to ensure that any clearances I test can accommodate all of my equipment. Whether THAT is fine enough for these wheels remains to be seen but it would still be important to have that info prior to commuting.

All of that is a lot of work, and so I nstead of reinventing the wheel I was curious if there was a finer standard…… which leads me back to the question.

Craig

[garethashenden]

All of that is a lot of work, and so I nstead of reinventing the wheel I was curious if there was a finer standard…… which leads me back to the question.

Kinda. There is an NMRA standard for Fine:N, but that's all there is. There are no gauges available for that, so you're kinda on your own. Looking at the numbers,  I think all the Fine:N is within the Standard:N specs, it just has tighter tolerances.

https://www.nmra.org/sites/default/files/standards/sandrp/pdf/S-3.1%202006.01.pdf

[Chris333]

Some people fill in the frog with solder and saw a gap for the flange. This way instead of the wheel riding on the riail the flange will ride on the gap. Like those shims everyone puts on Peco turnouts.

[peteski]

Craig, in N scale no matter how fine is the modeling standard, the dimensions are way out of spec (too wide) compared to 1:1 dimensions.  With 1:1 track the wheel tread's width is wide enough, and the frog flangeway is narrow enough for the railhead (of the closure rail and the frog's point) to continuously support the wheel tread as it crosses the gap.  I don't think that is feasible in N scale.

Making the flangeway shallower (so it supports the wheel's flange as it crosses the frog) is  probably the only way to mitigate the problem.  But if your equipment has multiple flange depths, then (as you noticed) some with deeper flanges will bump over that area of the frog.

[Brian M]

Tim Warris of Fast Tracks put out a series of videos from a while ago that step through all of the dimensions that come into play with wheels, wheel treads, frogs, etc.  I think most of the key points have already been made in this thread, but nonetheless, it is a very informative set of videos:

https://www.youtube.com/watch?v=JBdWvMHEN8s

-Brian.

[sschnabl]

I'm wondering if it would help if you tightened up the tolerances of the flange way width and made them narrower than the standard.  I know a #10 frog has to be very skinny and very sharp.  When I build my turnouts (mostly #6 and #8), I always struggle with how far in to put the frog rails to minimize that gap (I have FT fixtures).  I did build a curved crossover that I think has a #10 frog.  I've found that the point of the frog has to basically intersect with where the closure rail would be if it continued through the frog, if that makes sense.

Below is the curved crossover I built a few years ago with the #10 frog.  I use FVM wheelsets, and I believe they are the narrow tread.  I don't have any problems with any of my equipment going through either frog.


https://www.therailwire.net/forum/index.php?action=gallery;sa=view;id=37438

[craigolio1]

Kinda. There is an NMRA standard for Fine:N, but that's all there is. There are no gauges available for that, so you're kinda on your own. Looking at the numbers,  I think all the Fine:N is within the Standard:N specs, it just has tighter tolerances.

https://www.nmra.org/sites/default/files/standards/sandrp/pdf/S-3.1%202006.01.pdf

Thank you. This is what’ve as hoping to find as it gives me a place to start.

Craig

[learmoia]

When you noted narrow tread (width) wheel dropping in a frog gap, I assumed it was a gauge issue...

I'm a bit confused how the length of a #10 fog causes the issue?  Maybe for 28" wheels, but as the wheel size goes up, the ability to bridge the gap in a long frog shouldn't be an issue...

I'll watch that video tonight.

Nevermind.. I looked at that photo... I think I get it now.. 

[craigolio1]

I'm wondering if it would help if you tightened up the tolerances of the flange way width and made them narrower than the standard.  I know a #10 frog has to be very skinny and very sharp.  When I build my turnouts (mostly #6 and #8), I always struggle with how far in to put the frog rails to minimize that gap (I have FT fixtures).  I did build a curved crossover that I think has a #10 frog.  I've found that the point of the frog has to basically intersect with where the closure rail would be if it continued through the frog, if that makes sense.

Below is the curved crossover I built a few years ago with the #10 frog.  I use FVM wheelsets, and I believe they are the narrow tread.  I don't have any problems with any of my equipment going through either frog.


https://www.therailwire.net/forum/index.php?action=gallery;sa=view;id=37438

Your turnout looks really good and the frog does look “tighter” than mine. Your idea is exactly what I was considering. I’m thinking of measuring the flange width on all of my varieties of car and loco wheels to come up with a minimum clearance required, see how that compares with the NMRA fine n spec above, and start with that. I’ll start with one turnout and if I can find a happy medium that works I’ll be good to go. If not I’ll use other solutions like the shims.

Craig

[sschnabl]

Of course looking at that photo reminds me that I have to fix the head block ties.  I don't know what I was thinking.   

[rodsup9000]

  Don't know if this will help.  I fill the frog area with solder and then use one of my old (not any of my good ones) NMRA gauges and scrape the solder out till the depth is correct, Then slope the area before the place the flange has to ride on the bottom of the frog for the crossing gap. Make the slopes as long as possible. Any wheels with flanges larger than the depth will ride over it without hardly any notice at all. 

[ednadolski]

I fill the frog area with solder and then use one of my old (not any of my good ones) NMRA gauges and scrape the solder out till the depth is correct

This is rather the old-school method.  Just use lead-free solder -- filings from leaded solders are toxic.

Ed