Atlas Code 55 #7 turnout and Bluebox Kato SD40

[CRR Chase]

I was messing around the other night, and noticed my older Kato SD40 engines are struggling to navigate a turnout.

The turnout is the atlas code 55 turnout, and the issue is the older run SD40 seems to "lift up" and "hang" in the frog. the unit fits the wheel gauge but, the wheel profile is noticeably  different from the newer Kato SD40. the newer unit has no issue. The simple easy fix, would be to just swap out the wheels on the older Kato, which I can do.

My curiosity has me wondering, is there a fix for the turnout? I know Atlas 55 turnouts have been cantankerous for some of us, but it there a solution to fixing the frog, or would i risk damaging the frog, rendering it un-usable?

I am thinking I could file it.. but I am not sure about that, because I knoe they "Plate" their metal. at least ive heard that..

have you folks had any success with modifying, or correcting the turnouts from atlas?

[John]

Do the wheel flanges fit in the guage properly .. they are probably too deep .. I wouldn't screw with the frog .. because filing will remove what little plating there is on it and expose the mystery metal

[sschnabl]

The first thing I would check is to make sure all of the rails are in gauge, seeing as how you already checked the wheels and they were fine.  If those check out, then I would suspect that the wheel profile might be the issue.  You said this is different than your other loco.  Are these "pizza cutters" with deep flanges?  If so, you would either need to swap out the wheelsets or file down the area between the frog and the wing rail.  The flanges of the wheels could be riding up in this area and essentially lifting the wheel off of the rail a bit.

Scott

[robert3985]

I was messing around the other night, and noticed my older Kato SD40 engines are struggling to navigate a turnout.

The turnout is the atlas code 55 turnout, and the issue is the older run SD40 seems to "lift up" and "hang" in the frog. the unit fits the wheel gauge but, the wheel profile is noticeably  different from the newer Kato SD40. the newer unit has no issue. The simple easy fix, would be to just swap out the wheels on the older Kato, which I can do.

My curiosity has me wondering, is there a fix for the turnout? I know Atlas 55 turnouts have been cantankerous for some of us, but it there a solution to fixing the frog, or would i risk damaging the frog, rendering it un-usable?

I am thinking I could file it.. but I am not sure about that, because I knoe they "Plate" their metal. at least ive heard that..

have you folks had any success with modifying, or correcting the turnouts from atlas?

If you've got one, or a couple of engines that won't run on a turnout, but all the rest of your engines and cars do, it's not the fault of the turnout, it's a problem with the engines....so, the logical choice is to fix the engines, not mess with the turnout.

That said, if the older engine's wheels are in gauge...I mean perfectly in gauge, then the problem, especially since the turnout is an Atlas55 turnout, is probably overly deep flanges (pizza-cutters) on the older engines, since Atlas55 track won't run cars or engines with pizza cutter flanges because the flange clearances on them are built to NMRA standards, and many older N-gauge wheelsets weren't.

Just because I'm obsessive, I would carefully check the gauge again on all the older engine's wheelsets just to make sure the wheelsets...all of them...are perfectly gauged...especially not narrow...because narrowly-gauged wheelsets do exactly what your older engines are doing...lifting up, and "hanging" when attempting to traverse the turnout's check gauge...which is the space between the guard rails and the frog's wing rails.

Once again, IF the older engines' wheelsets are truly gauged properly and they're still lifting up at the frog, then it's the pizza-cutter flanges on the older engines.

So, the easy and logical solution is to change out the offending engines' wheelsets, either with other, newer wheelsets you get from another Kato engine, or from ordering replacements from Kato.

It's one of the things that N-scale modelers should be aware of, that Atlas55 won't run cars or engines with pizza-cutter flanges, because the deep flanges hit the spikeheads and frog bottoms.

The two other Code55 track brands, Peco55 and Micro Engineering Code55, don't have this problem since their spikeheads are much smaller than Atlas55's way oversized blobs that have no resemblance to spikeheads.

Cheerio!
Bob Gilmore

[CRR Chase]

The first thing I would check is to make sure all of the rails are in gauge, seeing as how you already checked the wheels and they were fine.  If those check out, then I would suspect that the wheel profile might be the issue.  You said this is different than your other loco.  Are these "pizza cutters" with deep flanges?  If so, you would either need to swap out the wheelsets or file down the area between the frog and the wing rail.  The flanges of the wheels could be riding up in this area and essentially lifting the wheel off of the rail a bit.

Scott

this is what i was thinking...

[CRR Chase]

If you've got one, or a couple of engines that won't run on a turnout, but all the rest of your engines and cars do, it's not the fault of the turnout, it's a problem with the engines....so, the logical choice is to fix the engines, not mess with the turnout.

That said, if the older engine's wheels are in gauge...I mean perfectly in gauge, then the problem, especially since the turnout is an Atlas55 turnout, is probably overly deep flanges (pizza-cutters) on the older engines, since Atlas55 track won't run cars or engines with pizza cutter flanges because the flange clearances on them are built to NMRA standards, and many older N-gauge wheelsets weren't.

Just because I'm obsessive, I would carefully check the gauge again on all the older engine's wheelsets just to make sure the wheelsets...all of them...are perfectly gauged...especially not narrow...because narrowly-gauged wheelsets do exactly what your older engines are doing...lifting up, and "hanging" when attempting to traverse the turnout's check gauge...which is the space between the guard rails and the frog's wing rails.

Once again, IF the older engines' wheelsets are truly gauged properly and they're still lifting up at the frog, then it's the pizza-cutter flanges on the older engines.

So, the easy and logical solution is to change out the offending engines' wheelsets, either with other, newer wheelsets you get from another Kato engine, or from ordering replacements from Kato.

It's one of the things that N-scale modelers should be aware of, that Atlas55 won't run cars or engines with pizza-cutter flanges, because the deep flanges hit the spikeheads and frog bottoms.

The two other Code55 track brands, Peco55 and Micro Engineering Code55, don't have this problem since their spikeheads are much smaller than Atlas55's way oversized blobs that have no resemblance to spikeheads.

Cheerio!
Bob Gilmore

Thank you sir.. I think the wheel change is the fix. I'll buy a bunch more... Already have some for other projects..
 

[peteski]

Even very old Kato models never had anything remotely resembling "pizza-cutters". Current wheels they have noticeably narrower tread and slightly smaller flanges, but the older wheels should still work with Atlas C55 turnouts. After all I believe Atlas still uses what is a knockoff of the older Kato wheels with wider tread and deeper flanges, and they shoudl run fine through Atlas' turnouts.



This photo shows Kato's current "semi scale" wheels on the bottom, and Atlas wheels on top (which would be close in appearance to what Older Kato wheels would have looked like).  I'm curious if the older Kato wheels in your SD40 look like the Atlas wheels?

I wonder if the problem is the long wheelbase of the 3-axle truck. If the wheelsets do not have much lateral play, the truck might be too stiff to correctly negotiate the tight Atlas flangeways in the frog and guardrail.

[chuck geiger]

The first thing I would check is to make sure all of the rails are in gauge, seeing as how you already checked the wheels and they were fine.  If those check out, then I would suspect that the wheel profile might be the issue.  You said this is different than your other loco.  Are these "pizza cutters" with deep flanges?  If so, you would either need to swap out the wheelsets or file down the area between the frog and the wing rail.  The flanges of the wheels could be riding up in this area and essentially lifting the wheel off of the rail a bit.

Scott

Just did this with the older Atlas GP-9 Trainsmaster having the same problem on one turnout. File and smooth out the top of the frog and don't ride up. I also noticed this might be a turnout that is not super secured in the meat or center area of the turnout and mainly on the ends and diverging track.

[robert3985]

Just did this with the older Atlas GP-9 Trainsmaster having the same problem on one turnout. File and smooth out the top of the frog and don't ride up. I also noticed this might be a turnout that is not super secured in the meat or center area of the turnout and mainly on the ends and diverging track.

The OP has two engines that don't work in that turnout.  All the rest of his engines and cars run through it just fine.  This logically means it's the two engines' problem, not the turnout's. 

Fix the engines, don't mess with the turnout....especially filing an Atlas55's plated mystery metal frog.

Cheerio!
Bob Gilmore

[jagged ben]

Check the wheel guage.   Again.

[peteski]

Another thing to try would be to drop the truck out of the chassis and roll it by hand through the turnout and see what exactly is the problem.  It will be easier to see with a bare truck.

You just need to remove the shell and the fuel tank and slightly loosen the screws holding the frame halves. Then spread the frame halves just a little and the truck should just fall out.

[robert3985]

Another thing to try would be to drop the truck out of the chassis and roll it by hand through the turnout and see what exactly is the problem.  It will be easier to see with a bare truck.

You just need to remove the shell and the fuel tank and slightly loosen the screws holding the frame halves. Then spread the frame halves just a little and the truck should just fall out.

@peteski Excellent advice!

Cheerio!
Bob Gilmore

[John]

A lot of good suggestions here from the brain trust - it's always hard to troubleshoot without seeing the patient first hand .. but based on what evidence we have is leading toward wheel gauge  / flange depth / truck related..

[NtheBasement]

One quick check is if the turnout is flat, i.e. the tops of the rails and frog are coplanar.  Turn off power, put a steel ruler edge-down across rails and frog, get your eyes down to that level and see if you can see where light comes out under the ruler.  Different loco's trucks wiggle differently and some handle uneven rail better than others.

Second check is run in very slow motion and watch where the wheel comes up.  I had one case where the wheel raised up a bit before the turnout that it finally derailed at.

[altohorn25]

Swap the wheels out of the truck with the newer "low profile" geared wheels from Kato.  They drop right into the truck.  This should fix the problem.