If I 2-railed my Lionel Cab Forward (product number is 6-11462 if it matters), what would be the new minimum curve that it could pull cars on?
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Personally you could use O72, but lager is better
@Dave Koehler posted:Personally you could use O72, but lager is better
"072", in 3-Rail speak, is only 36 inch radius, in 2-Rail SCALE terms. Thus, nowhere near large enough radius curve for a large 2-Rail SCALE articulated steam locomotive model.
Hot water I gathered converting a 3 rail to 2 rail should not effect the radius !
@Justin Acuna posted:If I 2-railed my Lionel Cab Forward (product number is 6-11462 if it matters), what would be the new minimum curve that it could pull cars on?
What does it operate on now?
@Dave Koehler posted:Hot water I gathered converting a 3 rail to 2 rail should not effect the radius !
Converting ANY locomotive to 2-Rail SCALE from 3-Rail definitely does effect the size requirement of curves. Many 3-Rail locomotive models have blind drivers, i.e. no flange, while 2-Rail SCALE models have all wheels flanged, plus the flanges and tire treads are more prototypically scale.
Assuming you have the same arrangement of blind drivers to flanged ones, there is no reason it should require a larger radius to operate. The scale couplers are closer connecting so that may be a bit of a concern. However, just because the tighter radius is possible it may not be desirable. 48" radius is about minimum for scale length passenger cars. 54" is recommended for most 2 rail locomotives with all flanged drivers.
If you are going to use all flanged drivers, then yes a larger radius would be required.
If you are going to go through the entire exercise, making a decent-looking model with proper tailbeam and pilot beam, and proper engine spacing and tender drawbar, double the radius to about 72".
If you just want to run 3-rail models on 2-rail track, pay attention to Hot above - retain the big flanges, insulate one side, and run on 2-rail Gargraves track. Should take the same radius as the 3-rail version, and you can convert back any time you start to miss the center rail.
Absolute cheapest and best way: Sell it, and buy a 2-rail Sunset version. Stay away from that seller who offers Sunset for $2150.
Opinion.
If you go fully flanged, you'll likely need a 72" radius (O-144). Though the Lionel likely doesn't have a tail beam and could possibly negotiate a sharper curve, I'd recommend against it for aesthetics and smoother operation.
@mwb posted:What does it operate on now?
O-72 but I think that's because it currently blind center drivers.
@AGHRMatt posted:If you go fully flanged, you'll likely need a 72" radius (O-144). Though the Lionel likely doesn't have a tail beam and could possibly negotiate a sharper curve, I'd recommend against it for aesthetics and smoother operation.
To be clear, you recommend not fully flanging it?
@bob2 posted:If you are going to go through the entire exercise, making a decent-looking model with proper tailbeam and pilot beam, and proper engine spacing and tender drawbar, double the radius to about 72".
If you just want to run 3-rail models on 2-rail track, pay attention to Hot above - retain the big flanges, insulate one side, and run on 2-rail Gargraves track. Should take the same radius as the 3-rail version, and you can convert back any time you start to miss the center rail.
Absolute cheapest and best way: Sell it, and buy a 2-rail Sunset version. Stay away from that seller who offers Sunset for $2150.
Opinion.
$2150?? Seems a bit high...
@GG1 4877 posted:Assuming you have the same arrangement of blind drivers to flanged ones, there is no reason it should require a larger radius to operate. The scale couplers are closer connecting so that may be a bit of a concern. However, just because the tighter radius is possible it may not be desirable. 48" radius is about minimum for scale length passenger cars. 54" is recommended for most 2 rail locomotives with all flanged drivers.
If you are going to use all flanged drivers, then yes a larger radius would be required.
Yeah, I'm trying to stay at a minimum radius of 54" but there's one spot that's proving difficult...but that's off topic.
54” radius gives a scale Mikado fits. I have to “narrow” the tail beam and make a little extra space for the lead truck wheels for 64” radius.
@Justin Acuna posted:To be clear, you recommend not fully flanging it?
Actually, if I was going to go through the trouble and expense of 2-railing a steam locomotive, I would go fully-flanged. I'm sorta living on both worlds and my Northerns, my Cab-Forward, and my S2 Turbine are hi-rail since my likely layout design is going to have a ruling radius of between 42" and 45". The operation will support my MTH scale-wheeled Big Boy, which can handle 36" radius (O-72) because of it's 3-rail roots and my scale-wheeled Hudson because of its shorter driver wheelbase. My scale-wheeled diesels can all squeeze through 36" radius as well. Because I've acquired pure 2-rail locomotives as well, the layout will go both ways.
There are other reasons to go fully flanged if you convert to 2-rail. One is that the wheel treads will be much narrower than their hi-rail counterparts -- by about 50%. This will have the wheels hanging in space over the rails on sharp curves, or worse dropping into and/or outside of the gauge and derailing if the drivers are sprung. On locomotives with long driver wheelbases and/or a lot of drivers, this is more prevalent. The one blind driver exception I can think of off the top my head is the PRR 2-10-0 which had flanges on the #1, #3 and #4 axles, while #2 and #5 were flangeless, so hold that one in your trivia bag when someone says no steam locomotives had blind drivers. Bob probably knows of others.
By the way, if I had the space, I'd go with 72" radius and larger in a heartbeat -- even with hi-rail equipment. The look and smooth operation is worth it. I had designed a backyard layout for when I was living in California that actually had 96" minimum radius (O-192) with a couple of 144" radius (O-288) curves.
@AGHRMatt posted:Actually, if I was going to go through the trouble and expense of 2-railing a steam locomotive, I would go fully-flanged. I'm sorta living on both worlds and my Northerns, my Cab-Forward, and my S2 Turbine are hi-rail since my likely layout design is going to have a ruling radius of between 42" and 45". The operation will support my MTH scale-wheeled Big Boy, which can handle 36" radius (O-72) because of it's 3-rail roots and my scale-wheeled Hudson because of its shorter driver wheelbase. My scale-wheeled diesels can all squeeze through 36" radius as well. Because I've acquired pure 2-rail locomotives as well, the layout will go both ways.
There are other reasons to go fully flanged if you convert to 2-rail. One is that the wheel treads will be much narrower than their hi-rail counterparts -- by about 50%. This will have the wheels hanging in space over the rails on sharp curves, or worse dropping into and/or outside of the gauge and derailing if the drivers are sprung. On locomotives with long driver wheelbases and/or a lot of drivers, this is more prevalent. The one blind driver exception I can think of off the top my head is the PRR 2-10-0 which had flanges on the #1, #3 and #4 axles, while #2 and #5 were flangeless, so hold that one in your trivia bag when someone says no steam locomotives had blind drivers. Bob probably knows of others.
By the way, if I had the space, I'd go with 72" radius and larger in a heartbeat -- even with hi-rail equipment. The look and smooth operation is worth it. I had designed a backyard layout for when I was living in California that actually had 96" minimum radius (O-192) with a couple of 144" radius (O-288) curves.
Yeah, I'm trying to stay as wide as possible but reality sometimes gets in the way.
When I lived in places which had limited layout space I worked with smaller locomotives and cars in 0 scale. Once I even moved to a smaller scale to run large equipment. Then again when having a very large space available I went to #1 scale on my way up to 1": ft.
I have a hard time thinking through the process of forcing large equipment to function in a limited space.
I now have a large space and broad curves but the equipment that looks best IMO are the medium sized locos and cars in medium to short trains. They make my good sized layout appear even larger.
@Justin Acuna posted:O-72 but I think that's because it currently blind center drivers.
Thank you; that explains the current operating tight radius. As noted by others, to retain that radius you'd have to retain the blinded drivers with conversion to 2 rail, otherwise you're going to have to consider a good bit larger curve.
