Looking for Max Shim Thickness for Peco 100 Guard Rails

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beiland

Well-Known Member
I bring this up as an individual subject as I am sure there are LOTS of Peco Code 100 turnout users out there. And there are likely LOTS of those users that have experienced some derailing problems in some situations

There is a relatively simple modification that will improve their performance. It involves the guard rail 'slot' across from the frog area. I'm almost surprised that Peco themselves have not offered some sort of 'fix kit'

The flangeway across from the frog is just a bit too large for the needs of most modern American train models. This excessive width allows the axles to shift away from that outer rail and over towards the frog slot. The wheel(s) may then encounter the tip of the frog and ride up over the tip of the frog, resulting in a derail.

There have been a significant number of folks who have shimmed up this flangeway in the guard rail to help prevent this problem. I've seen some folks that report the use of shims of .010".

I'm searching for what might be other suggestions/experiences for a maximum thickness that might be used??
 
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beiland

Well-Known Member
Fine Tuning Peco Code 100 Curved Switch Check Rails


Using brass shim on guard rail,..pretty clean installation.


Interesting observation about backing thru the turnout verses forward picking of the frog.
 

beiland

Well-Known Member
from another forum,...

When you bought Peco turnouts that were supplied with paperwork in the box they themselves said to glue .010 thou shims to the guard rails if you ran scale type wheels sets. I have shims in mine .010 thou in the older ones. These newer ones with out the adjustable spring tensioner have up to .020 thou. I also now make the guard rail longer so that the end is not almost opposite the tip of the frog. I found once I had the wheel set further over I wasn't getting the short problem as much from the two merging rails at the frog of insulfrog type turnouts.


Hope this helps Les
 

beiland

Well-Known Member
Shim Experiments


One of the reasons I brought this subject up at this time is that I had been doing some testing on a custom double crossover arrangement that had one leg going off via a curved (dbl-curve I term it) Peco turnout. Upon exiting that curved turnout I sought for the track to enter a rt-hand turnout that would eventually feed a container port facility. I decided to experiment around to determine what size turnout this might be. Here are the 3 Peco options I was considering,..






1) Lg size Peco:
All of my locos would go thru this turnout, including the 2-10-4 Broadway T-1





2) Med size Peco:
The 2-10-4 would not go thru this without consistently derailing its first driver on the point of the frog. Several of my 4 driver axle driver steam locos also had problems here. The IHC 4-8-2 Mountain did NOT have a problem here ( I surmise that is probably due to its slight cookie-cutter flanged wheels).


3) Sm size Peco:
All steamers but the IHC mountain had problems here.


NOTE: None of the diesels had any problems with all 3 sizes, including the very small flanged 6 axle ones.





At first I was wondering if it was the 'S' curve coming off the curved Peco that might be the problem. But I had also been aware that some shimming of Peco guard rails had been tried successfully in the past,...might this solve a portion of my problem? Good time to experiment while I had this test bed set up.



I looked around for some plastic or metal strips I might utilize to conduct a few experiments. I found VERY limited materials either in my storage trailer, nor in the local stores. Remember I am looking for something probably .010” to .020” thick, by .040” to .060” tall.
1) Metal faced tape:
Why not multiple layers of metal-faced duckwork tape,...total failure

(metal tape on upper guide rail in photo, metal shim on lower guide rail )



2) Styrene strips:
I had some .015” thick strips but they were 1/4” tall, but then I found some Evergreen ladder strips, and some particular ones that were .020 x .040. I tried gluing these in to the flangeway of that Sm Peco (figured that if I could make the Smaller radii Peco work that would prove the effectiveness of this approach).












It did work, for all of the steamers except the 2-10-4. And the .020” thickness seemed to work also.



I had a problem getting the styrene strip to fully glue to the guard rail. You can probably see that its not fully bonded in its center portion. Need more careful gluing, and perhaps some better glue than the styrene bonding agent I used. I'm sure my old Tenax 7 would have done a better job. It was also tough to get the bonding solution on JUST the face between the guard rail and the styrene strip,...invariable some solution would end up on the outer side disrupting that nice smooth side.






NOTE !! I did discover something about the height of this shimming piece. When I first glued it in I paid particular attention to NOT let it be any higher that the other tops of the rails. As it turns out that was a little too low. When I popped it off and reglued it higher, it worked even better. I am now convinced this shim piece needs to be a bit taller than the adjacent rail, particularly for our very smalled flanged wheels on modern American equipment. Plus, this will not negatively affect matters as there are no portions of our locos or cars that project down this far directly adjacent to the inside rim of their wheels.









3) Metal strips:
Looking back at that video I posted early on I began to give more serious consideration to the metal shim idea. I had a .010” thick sheet of steel. Could I cut it into thin strips? I gave it a try with big thin snips, then had to reshape that little thin strip into a presentable shape,












I'm pretty much convinced that I want to go the metal shim route. But I was not finding a ready made strip of metal at first. Finally I have found two candidates from K&S
http://www.ksmetals.com/29.html
815020 & 815021


Both of these are 1/64” thick (.015”),...nice compromise between .010” & .020'.
One is 1/16” (.0625”) tall which would make it slight proud if its bottom edge were sitting on the tie plates. The other is 3/32” (.093”) tall which I figure would be sitting on a slight slot cut into the plastic ties/tie plates with a hand held cut-off wheel rubbed back and forth.
 

trailrider

Well-Known Member
I have a number of curved PECO turnouts, and don't recall having this problem with them. However, it is good to know about it, and how to fix the problem, if it occurs! Thanks! :)
Me and my big mouth! I have a kitbashed 2-10-4 that I store on a siding which branches off a curve, but with the siding coming off on the straight side of the Peco turnout. Haven't used the siding much. Today, when I tried backing the locomotive onto the siding, the 4-wheel trailing truck derailed...several tries! I cut a piece of .010" brass sheet so it projects above the guardrail and the stock rail. It works, even though I didn't cement it in yet. Probably will use some CA. OTOH, if I can find a short Shinohara turnout, I may substitute that instead. Funny thing is that trains proceeding into the curved portion of the turnout from the point of the frog, do NOT derail? Go figure. :confused:

Well, I finally got a Round Tuit and cemented the shim in place with gap-filling CA. Ran the locomotive back and forth several times and NO PROBLEM! :D Thanks for the suggestion, folks! BTW, I checked at my LHS (Caboose in Lakewood, CO, and they haven't seen hide nor hair of a U.S. speced PECO turnouts, yet! Also checked with several other dealers at a model railroad show who carry PECO turnouts. No joy their either! I looked at replacing the PECO turnout with a modified Shinohara, but that wouldn't fit in. So, looks like the problem is solved!
 
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beiland

Well-Known Member
I'm pretty much convinced that I want to go the metal shim route. But I was not finding a ready made strip of metal at first. Finally I have found two candidates from K&S
http://www.ksmetals.com/29.html
815020 & 815021
Both of these are 1/64” thick (.015”),...nice compromise between .010” & .020'.
One is 1/16” (.0625”) tall which would make it slight proud if its bottom edge were sitting on the tie plates. The other is 3/32” (.093”) tall which I figure would be sitting on a slight slot cut into the plastic ties/tie plates with a hand held cut-off wheel rubbed back and forth.

I got a sample of each of these strips in, and I'm convinced that the smaller one is the one to use,...the part# 815020....1/64" thick, 1/16" tall.

Upon reviewing again this subject of problems with derails in Peco turnouts, I'm now pretty satisfied that the large size/radius Pecos are not so venerable to this derail problem. BUT the mediums and certainly the smalls are, particularly with steam engines. So now I am pretty much convinced that I will have to shim many of my Pecos.

I likely may have to do my 3-ways? Does anyone have particular experience with these??
 

wvg_ca

Active Member
it's recommended to use styrene, 10 to 15 thousanths of an inch ..
and the styrene strip should stick up above [slightly] the guard rail
 

beiland

Well-Known Member
My preference for the metal strip verse the plastic one is 2 fold:
1) more durable in the long run
2) the possibility of winging it's ends out to effectively make the guard rail longer,..like this plastic one...






On the other hand I also like the way this one locks itself around the existing plastic guard rail,..



I suspect this one would also have less problems interfering with track cleaning pads.



I must also do a little measuring as I believe I detected a difference in guard rail spacing amoung different size Peco turnouts, and maybe even date of manufacture??
 

autocoach

Active Member
I can't give you a specific answer but there is a wealth of information at the British model railroad (model railway) forum. rmweb.uk.com In the UK about 90% of the modelers use Peco products and there is a wealth of information. The forum software they use is almost identical to this forum.
 

beiland

Well-Known Member
I can't give you a specific answer but there is a wealth of information at the British model railroad (model railway) forum. rmweb.uk.com In the UK about 90% of the modelers use Peco products and there is a wealth of information. The forum software they use is almost identical to this forum.
That link did not work for me?
 

Andrey

New Member
I am now convinced this shim piece needs to be a bit taller than the adjacent rail, particularly for our very smalled flanged wheels on modern American equipment.
Hello! Yes, high guard rails do their job! This is video:


This is video guide how to upgrade turnouts:

 

beiland

Well-Known Member
I'm getting ready to do a little 'mass production' of the shimming of my Peco turnouts on my layout,...certainly most of the tighter radius ones that my steam engines may have to traverse,...and thus that are inaccessible in staging areas. Tighter radius I am defining as the Code 100 Peco smalls, mediums, small wyes.


I have decided to utilize .01" thick styrene material, and super glue it in place. I hope to find black styrene locally so I don't have to paint the ones on the upper decks.


As I reviewed a few of the discussions I had started on this subject of shimming, I discovered these 2 comments that I thought was very helpful,..


1) I believe that I just used 0.010 thick Evergreen strip. If you use plastic liquid cement, you need to make sure that the strip is held firmly against the guard rail until the cement sets. CA would probably work better.
2) I made a couple of CA applicators that hold different amounts of CA.
One is a simple sewing needle stuck eye first into a wooden handle. It is great for tiny amounts of CA. It's just the same as using a pin but I find the handle makes it easier to hold.
I made the other one by grinding off the top of the eye of a needle and sticking the pointy end into a wooden handle. The remaining part of the eye forms a wye and it holds a bit more CA than the first one, but not so much that it flows everywhere. You can vary the amount that it will hold depending on how far down you grind the eye.
The wooden handles make the needles easy to handle, and when I put them down on the workbench they won't glue themselves to the cutting mat because the tip stays above the surface.
 

beiland

Well-Known Member
Posted on another forum just recently. Has anyone else experienced this??

Years ago when I built my Buffalo Line I used Peco code 100 curved turnouts in a few of my staging yards for the ladder. Discovered that when backing long trains into the tracks that cars would derail at the frogs. So I measured the gap between the guardrail discovered that it was a bit too wide so I then got a small length of styrene about .010 less than that measurement. Been so long ago I do not remember the sizes. Anyway I would put the piece of styrene in the gap then using a pair of square nose line mans pliers gently squeeze between the rail and guardrail as the plastic they use is fairly soft . When the styrene spacers is tight I stop and remove the piece and the guardrail is now closer to the rail with no white styrene shim to deal with. You don't have to move the entire guard rail just the section directly across from the point of frog. Have never broken a Peco doing this and 29 years later they are still in service with no derailments. Nice thing is this can be done easily when the turnout is in place and ballasted !
 

GeeTee

Active Member
Me and my big mouth! I have a kitbashed 2-10-4 that I store on a siding which branches off a curve, but with the siding coming off on the straight side of the Peco turnout. Haven't used the siding much. Today, when I tried backing the locomotive onto the siding, the 4-wheel trailing truck derailed...several tries! I cut a piece of .010" brass sheet so it projects above the guardrail and the stock rail. It works, even though I didn't cement it in yet. Probably will use some CA. OTOH, if I can find a short Shinohara turnout, I may substitute that instead. Funny thing is that trains proceeding into the curved portion of the turnout from the point of the frog, do NOT derail? Go figure. :confused:

Well, I finally got a Round Tuit and cemented the shim in place with gap-filling CA. Ran the locomotive back and forth several times and NO PROBLEM! :D Thanks for the suggestion, folks! BTW, I checked at my LHS (Caboose in Lakewood, CO, and they haven't seen hide nor hair of a U.S. speced PECO turnouts, yet! Also checked with several other dealers at a model railroad show who carry PECO turnouts. No joy their either! I looked at replacing the PECO turnout with a modified Shinohara, but that wouldn't fit in. So, looks like the problem is solved!
peco1.jpg



Note the difference in the guard length between each turnout. The one on the right is longer.


peco2.jpg



Now look at the guard position relative to the point of the frog.


peco3.jpg


Note the guard "throat" opens before before the frog point.
peco4.jpg

the turnout outside rail gauges to tight not enough clearance between the frog and the outside rail .The flange way clearance is against the frog on one side and the other lands on top of the rail.

The No Go flange gauge fails on all.

Apparently later Peco's have less of a problem , but there still seems to be an issue . Even with shims there may still be a problem with properly gauged RP wheels . They may get squeezed out the turnout.
 

beiland

Well-Known Member
@GeeTee,
Your photos are a little too blurry and dark to be really useful in support of your posting. I might also suggest that you google the 'Peco flangeway' subject and look thru a number of more extensive discussions on this subject. and on other forums.

I have over the years read quite a bit on the subject, and somewhat recently did some experiments on the problem(s).

1) Steam engines seem to be the most affected, and those steam engines that have multiple in-line drivers.

2) Diesel engines, even those with 3 axle trucks, and very small flanged wheels did not seem to have problems.

3) The .010" shims seem to adequately effective in most all cases. I did try out .015" and .020" shims and did not find that they 'squeezed' the wheels out of the turnout. But since the .010" ones worked fine I just figured I would use this figure,....then some of my few Euro trains would have less problems.

4) I do NOT think the use of a 'proud' shim is a good idea, as it will surely interfere with track cleaning cars.

5) Shim experiments https://model-railroad-hobbyist.com/node/35992?page=0#comment-379092


I am really interested to learn more about this 'new idea' of bending the guard rail rather than shimming it. That same fellow recently added this comment,
I have a bunch of Evergreen styrene . So I found out what fit tightly in a non modified Peco . Then subtracted .010 from that and that's what I used as a spacer when I bend the guardrail. The line mans pliers I use have a fairly wide square jaw end . You only need to move the guardrail about .010 and only the portion leading up to the point of frog and the point. I've done Peco's that have been in place for over ten years and have yet to have a failure. --- Ken
 




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