Peco Code 83 Turnouts - Narrowing Check Rail Gap?

[Ian J.]

Hi all,

 

At some point in the future I have a job to do narrowing the check rail gap on a batch of Peco Code 83 turnouts, both straight and curved, being used on the fiddleyard boards of my layout idea. This is to allow the back-to-backs of RTR stock to be eased out to 14.8mm to allow for better quality running, and the scenic sections will be using handbuilt finescale OO track.

 

Can anyone advise on best ways to do this?

 

My current thoughts are to:

• lay the turnouts
• cut the stock rail check rails off
• file clearance from the base of the rail
• clear out the plastic from between the sleepers
• put two small, flat-headed screws between the sleepers
• solder the check rail back in place with a narrower gap

 

Does this sound OK, or is there a better way?

[Il Grifone]

IMHO it's certainly the way to go, but I would replace a couple of plastic sleepers with PCB and solder both stock and check rails to that rather than use screws which will fix the track solidly to the baseboard and not allow any 'give' *. The narrower the flange gap, the less tolerance it has to shift.

I would be inclined to replace the wing rails as well.

 

* IMHO advisable both for trackholding and electrical pickup.

[Ian J.]

Interesting thoughts. I would think that to do so would most likely require removal of a couple of sleepers before laying the turnout, in order to do the job well. That's possible at the moment but I hadn't planned on it so will have to think through how it affects my track laying intentions.

 

The wing rails have to stay where they are. The Code 83 track has a 'floor' between the wing and nose intended for NMRA flanges to ride to prevent the wheels dipping across the gap. Digging that out is a non-starter and I don't think it will be an issue as long as I ensure that, as I already know I have to, any UK stock has any over-deep flanges turned down so they can ride the 'floor'.

[DCB]

A chap I bought bits and bobs off through eBay on a number of occasions narrowed Triang Super 4 check rails by gluing a strip of steel or brass to the side of the check rail.   Best of luck with soldering rail to screw heads.  I do it for functioning check rails on some awkward curves and it's a bit of a sod

[Ian J.]

Now here's a thought, something I hadn't realised. I checked the check rail gap on the Code 83 turnouts, and it 'turns out' that at about 1.2 mm it's somewhat less than UK Code 75 turnouts, which are around 1.5 mm. The NMRA standard is for gauge of 16.54 through the frog, with check rail gauge of 15.42, meaning an ideal gap of around 1.12 mm. Given that, it may be possible that a widened UK outline back to back of around 14.75 to 14.8 mm could get through without going the wrong side of the frog. I will need to experiment, but if that is so, I won't have to make any adjustments to the check rails at all, leaving the turnouts as is.

[Dagworth]

Superglue a piece of microstrip (10thou?) on the inside of the checkrails

 

Saves messing about with the structure of the points.

 

Andi

[Il Grifone]

14.8mm B2B is pushing it a bit, but should be OK as long as the flange is not thicker than 0.5mm and the check rail gap is not more than 1.2mm

[Ian J.]

So I did a little experimenting and it's not a good result.

 

I took an axle from a recent-ish Hornby wagon and widened out the wheels to just short of being tight on the rails on plain track. This gave it a 'back-to-back' of 14.75mm, as far as my digital calipers could tell. The wheels wouldn't run through the crossing of a code 83 #6 when the stock rail wheel was up against the check rail, as it left the V wheel hitting the V.

 

With the V wheel up against the V, I can see what appears to be around 0.1mm to 0.2mm daylight between the stock rail wheel and the check rail. Using the digital calipers, I've estimated the check rail gap at 1.2mm (it's not consistent through the check rail).

 

The only answer will be to either move the check rail or, as others have suggested, pack the outer edge of it with something to take up that approx 0.2mm extra gap that leaves the V wheel hitting the V. As the check rails are nickel silver (unlike the U.K. Streamline which are plastic), I'm wondering if soldering a pre-shaped strip of phospher bronze or such like might be possible? I doubt I could pre-shape a thin piece of plasticard, and I'm not sure gluing it would really be viable in the long run.

[Grovenor]

Much easier just to hand build your fiddle yard turnouts since you are going to do that for the scenic areas. Fiddle yard turnouts are a quicker build as you can cut the number of timbers by half or more, and a substantial saving over those expensive Peco points as well.

Or go for 00SF in the scenic areas to avoid all that fiddling with widening back to backs.

[Ian J.]

7 hours ago, Grovenor said:

Much easier just to hand build your fiddle yard turnouts since you are going to do that for the scenic areas. Fiddle yard turnouts are a quicker build as you can cut the number of timbers by half or more, and a substantial saving over those expensive Peco points as well.

Or go for 00SF in the scenic areas to avoid all that fiddling with widening back to backs.

 

The turnouts have all already been purchased, and that was because I am not interested in handbuilding them for the fiddleyard. I've never been happy with the idea of even narrower gauge track for scenic areas, so 00SF has always been out of the question.

 

I will have to do some experimenting on the best solution. I have a couple of spare Code 83 curved turnouts due to a minor change in turnouts I eventually settled on, so I will see how difficult each idea for narrowing the gap is likely to be then make a decision. Right now though I have other things to concern me so that slows things down, and it could be a few weeks before I have an answer.

[Ian J.]

My first thoughts for a modification are to try and add some 'fill' to the side of the check rail to narrow the gap, as per some suggestions.

 

To that end, I've measured the rail, and it looks like I'll need a 1.2mm wide / 0.175mm thick strip of some kind of metal that will solder to nickel silver to 'fill' the gap of the web related to the head. Then I need something similar, but 1.75mm wide and 0.2mm thick, to sit on the outside of that and be the actual padding to fill the gap between check rail head and stock rail head.

 

I did wonder about using thin plasticard strip, but I'm not sure it would be available that thin, and also I'm not sure how well it would glue to the nickel silver check rail, and also hold shape with the flared ends.

[Ian J.]

A little experiment tonight: I took one of the 'spare' turnouts and removed the 'clips' holding in the check rail on the non-stock rail side. Then I filed away some of the foot of the rail that faces the stock rail. This was done very awkwardly using fingers and tweezers to hold the check rail against a piece of scrap ply. The results weren't entirely clean, but good enough to know that if I could more reliably reduce the width of the foot on that side of the check rail and get it 'pointed' again so if fits against the double-sided clips that also hold the stock rail in place, then the gap would be reduced by the needed amount to get the gap to about 1mm. There is enough plastic in the base that Peco put in for the check rail to glue the check rail back into place, probably using Araldite or similar.

 

Any constructive advice on how to accurately reduce the width of the foot of the check rail on the stock rail side and 'reprofile' it would be gratefully received. I have around 60 of these little blighters to do and I want to be able to do the work cleanly and accurately.

[Ian J.]

OK, with a little help from a friend who had a suitable engineering tool for holding things, I have been able to reliable file down the foot of a check rail, keep the edge 'pointed' and fit it to the turnout. That reduced the check rail gap from 1.2mm to very near 1.0. That was then glued in place with a two part epoxy (B&Q's 'finest') and that seems to have held well. I'm not going to break the join deliberately and I have used enough pressure to feel confident that it's holding. Testing with a Hornby wagon with wheels at pretty much the maximum gap (14.75mm back to back) has the wagon running through the check rail cleanly and not hitting the V point.

 

The beauty of this way of narrowing the gap is it's probably easier to do once the turnouts are laid. This means I can get on with fiddleyard track laying for S&P and can worry about narrowing the gaps at a later date once everything's running well in 'coarse' mode.