Dual Gauge Peco SM32 Track
Posted: Mon Mar 18, 2019 6:09 pm
Not sure which section to post this in?
My initial plans for a Garden Railway layout started with using Mamod/MSS track. However after attending several 16mm NGM running days I was persuaded to use Peco SM32 track instead. My back garden (yet to be built) is relatively small so I needed to go with a small radius layout. The smallest radius Peco points are 38" radius so I decided to settle on using those together with 38" setrack curves & flextrack for the straights. The layout will effectively be a large rectangular oval with 2 passing loops/stations and two sidings.
I obtained a couple of 45mm gauge only locomotives, primarily to run on an indoor 45mm layout at a Heritage Railway, but was then tempted by the 7/8ths scale Accucraft Bagnall (an excellent runner with incredibly long running time). Peco only do a setrack SM45 curve in 600mm radius, so I was going to get very dizzy watching that Bagnall run round for over 45 mins. There will not be space for a separate 45mm track in my garden so my thoughts turned to dual gauge track.
This is available, but rather costly. I found that there would just be enough sleeper available on Peco SM32 track to mount a 3rd rail on the outside. As the layout is going to be a rectangular oval, if I put that 3rd rail on the inside of the oval, and had all the points going out of the oval then I could get away with just a straight 3rd rail on the points.
Coincidentally around this time, Tony Bird posted a topic on making a dual gauge side change for the track at CMES - https://gardenrails.org/forum/viewtopic ... ge#p124650
I purchased a supply of Peco Sl-802 rail chairs & Peco IL-8 Code 200 rail (this is listed under Gauge 1 rather than SM32, adding to the confusion), and thanks to Tony's topic, E.M.A. Model Supplies PLASTIC WELD.
I converted a panel of flexitrack, one setrack 38" radius curve & one RH point. A battery powered locomotive & 45mm stock ran OK over these, and I had pushed a live steam locomotive over them with no problem. So the rest of the track for conversion was put back into my 'To Do' list after I've built the back garden.
I've recently been offered another 45mm gauge only 7/8ths scale locomotive, but it has an unknown actual minimum required radius. So I needed to convert some more track to see if that loco will cope with just under 38" minimum radius. As I've not run a locomotive in live steam on this converted track I took the opportunity to run 2 of my 45mm gauge locos with a selection of 45mm rolling stock to check all was well so far.
Not obvious in that video but the Bachmann V Dump Car was bumping over the frog on the RH points. When I converted these I had not considered fitting a check rail for the 3rd rail, so when I converted the LH points I added a check rail, although not without some difficulty. My initial thoughts after that video running was it confirmed that an extra check rail was required, but before committing to that action I took a closer look at both points, and discovered a potential design fault. On the faulty RH point the nose of the frog is formed from the curved rail - Whereas on the LH point the nose of the frog is formed from the straight rail - So the gap between the check rail & the frog on the LH point is wider than the equivalent gap on the RH point, which is smaller than the flange on those Bachmann wheels. I got another LH point out of storage to convert to dual gauge, and that gap is big enough for the Bachmann flange, so converted it without an extra check rail. The Bachmann wagon ran through no problem.
I've filed down the side of the frog & adjacent check rail on the troublesome RH points so the Bachmann wagon runs through now rather than riding up over the frog.
Only 4 more points to convert now for the planned dual gauge circuit!
Code 200 rail obviously restricts what depth of flanges you can use, but I do not intend to use the larger flanged LGB wheels. Peco G-45 track is Code 250, thus 1/20th of an inch taller than Code 200.
Chris Cairns
My initial plans for a Garden Railway layout started with using Mamod/MSS track. However after attending several 16mm NGM running days I was persuaded to use Peco SM32 track instead. My back garden (yet to be built) is relatively small so I needed to go with a small radius layout. The smallest radius Peco points are 38" radius so I decided to settle on using those together with 38" setrack curves & flextrack for the straights. The layout will effectively be a large rectangular oval with 2 passing loops/stations and two sidings.
I obtained a couple of 45mm gauge only locomotives, primarily to run on an indoor 45mm layout at a Heritage Railway, but was then tempted by the 7/8ths scale Accucraft Bagnall (an excellent runner with incredibly long running time). Peco only do a setrack SM45 curve in 600mm radius, so I was going to get very dizzy watching that Bagnall run round for over 45 mins. There will not be space for a separate 45mm track in my garden so my thoughts turned to dual gauge track.
This is available, but rather costly. I found that there would just be enough sleeper available on Peco SM32 track to mount a 3rd rail on the outside. As the layout is going to be a rectangular oval, if I put that 3rd rail on the inside of the oval, and had all the points going out of the oval then I could get away with just a straight 3rd rail on the points.
Coincidentally around this time, Tony Bird posted a topic on making a dual gauge side change for the track at CMES - https://gardenrails.org/forum/viewtopic ... ge#p124650
I purchased a supply of Peco Sl-802 rail chairs & Peco IL-8 Code 200 rail (this is listed under Gauge 1 rather than SM32, adding to the confusion), and thanks to Tony's topic, E.M.A. Model Supplies PLASTIC WELD.
I converted a panel of flexitrack, one setrack 38" radius curve & one RH point. A battery powered locomotive & 45mm stock ran OK over these, and I had pushed a live steam locomotive over them with no problem. So the rest of the track for conversion was put back into my 'To Do' list after I've built the back garden.
I've recently been offered another 45mm gauge only 7/8ths scale locomotive, but it has an unknown actual minimum required radius. So I needed to convert some more track to see if that loco will cope with just under 38" minimum radius. As I've not run a locomotive in live steam on this converted track I took the opportunity to run 2 of my 45mm gauge locos with a selection of 45mm rolling stock to check all was well so far.
Not obvious in that video but the Bachmann V Dump Car was bumping over the frog on the RH points. When I converted these I had not considered fitting a check rail for the 3rd rail, so when I converted the LH points I added a check rail, although not without some difficulty. My initial thoughts after that video running was it confirmed that an extra check rail was required, but before committing to that action I took a closer look at both points, and discovered a potential design fault. On the faulty RH point the nose of the frog is formed from the curved rail - Whereas on the LH point the nose of the frog is formed from the straight rail - So the gap between the check rail & the frog on the LH point is wider than the equivalent gap on the RH point, which is smaller than the flange on those Bachmann wheels. I got another LH point out of storage to convert to dual gauge, and that gap is big enough for the Bachmann flange, so converted it without an extra check rail. The Bachmann wagon ran through no problem.
I've filed down the side of the frog & adjacent check rail on the troublesome RH points so the Bachmann wagon runs through now rather than riding up over the frog.
Only 4 more points to convert now for the planned dual gauge circuit!
Code 200 rail obviously restricts what depth of flanges you can use, but I do not intend to use the larger flanged LGB wheels. Peco G-45 track is Code 250, thus 1/20th of an inch taller than Code 200.
Chris Cairns