A 2 part question, can the o scale 2 rail gauge be used to check 3 rail equipment, if not is there a 3 rail version? Part 2, what tools/methods are best utilized to correct mis gauged wheels?
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As a thought: the tool I use is another, correctly-gauged truck or loco.... never had a "gauge gauge". (Funny - in the real RR industry, it is properly spelled "gage".)
The 2R gauge should work well enough, as O-gauge is O-gauge, even if it's O-scale, but things like 3RO flange depth/thickness may make it a little awkward.
1st question, answer: no. …….3 rail gauging is done primarily model by model. Long wheel base locomotives use a different gauging than shorter wheel base stuff. This is why the tread width of 3 rail tires are so wide. In a particular family of locomotives, you would find gauging to be the same and consistent, for example, the entire Railking line of 4-6-2’s -4-6-4’s would have a particular gauge that works best,…..In the Lionel postwar service manual, there’s a page about gauging, explaining this. If you’re unsure about the specific gauging on a particular model, best to ask someone on here to measure a known good model, to establish a base line for what you’re working on…..gauge is measured outside flange to outside flange, where the flange meets the tire …..
Pat
The only NMRA wheel gauges I have seen fit over the flanges. They Would not give and accurate measurement of three rail wheels. I use a caliper, can be vernier or digital and measure at the point where the flange meets the tire. Should be slightly less than 1.25” or five scale feet which all three and most all two rail track gauge is other than proto 48.
Pete
"Part 2, what tools/methods are best utilized to correct mis gauged wheels?" Pro tools would be a wheel puller and wheel press.
The wheel press is overkill. Usually a bench vise or 3” C clamp is all you need.
Pete
@Ken Wing posted:@Norton How much less is "slightly less?"
As Pat pointed out it partially depends on what you are running and how tight your curves. I run on 072 minimum and set the wheels at 1.235”-1.240”. For 027 maybe 1.225”-1.230”. Too narrow and you start hitting switch guard rails.
Measure your track too. Some track is wider than 1.250”.
Pete
@Norton posted:As Pat pointed out it partially depends on what you are running and how tight your curves. I run on 072 minimum and set the wheels at 1.235”-1.240”. For 027 maybe 1.225”-1.230”. Too narrow and you start hitting switch guard rails.
Measure your track too. Some track is wider than 1.250”.
Pete
Hitting guard rails seems to be my issue, running 042 curves, culprit is an 80s vintage williams aluminum passenger car. Also sounds like it's dragging on the rails hence wanting to check.
On postwar equipment the end of the axle is usually flush with hub of the wheel when the wheel is in gauge. On prewar equipment the axle usually extends out of the wheel hub a little way. As Pat said, best way is to check another loco that works properly. If you think you have gauge problems, also check for bent axle. The track gauge and wheel gauge are checked at different locations, which are points that will never make contact. The wheel gauge could be wider than the track gauge and everything will work fine. I use a digital caliper to check both wheel and track gauge. If I find a gauge number that looks correct, I try to record it. Lionel does show a back to back gauge for the 622 wheels, but its primary use is to locate the rollers. The back-to-back for the 622 is 1.100”.
The Lionel Engineering Standards do have detailed drawings for some of the wheels. The wheel geometry is very complicated and is not consistent. I rarely find wheels that the dimensions agree with the drawings. On Lionel locos the inside of the wheel hub frequently contacts the axle bearing taking the thrust. This means that the wheel gauge dimension also controls the bearing clearance.
Lionel was constantly working on their designs and adjusting dimensions. This was done both to improve operation and reduce cost. I am convinced that operational interchangeability was only guaranteed for the items made in a single product year.
@necrails posted:Hitting guard rails seems to be my issue, running 042 curves, culprit is an 80s vintage williams aluminum passenger car. Also sounds like it's dragging on the rails hence wanting to check.
Some of those vintage Williams passenger cars are known for dragging like bricks. Not the best rolling cars on the market. They tend to drag. I fiddled with these a long while back, and I found the best solution was a truck swap with something more modern from MTH. I tried a bunch of ways to make those Williams trucks to roll smoothly, and track nicely, but it wound up being a lost cause,…..you might have better results fiddling with them, but I never could get satisfied, and wound up swapping out the trucks …
Pat
@harmonyards posted:Some of those vintage Williams passenger cars are known for dragging like bricks. Not the best rolling cars on the market. They tend to drag. I fiddled with these a long while back, and I found the best solution was a truck swap with something more modern from MTH. I tried a bunch of ways to make those Williams trucks to roll smoothly, and track nicely, but it wound up being a lost cause,…..you might have better results fiddling with them, but I never could get satisfied, and wound up swapping out the trucks …
Pat
This was one of those too good to pass up deals that may cost more to fix than the car cost but appreciate the feedback. A truck swap may be the best solution.
@necrails posted:This was one of those too good to pass up deals that may cost more to fix than the car cost but appreciate the feedback. A truck swap may be the best solution.
If Pat can't diagnose and fix a mechanical issue, I think I'd move on and swap the trucks. 
Today, I measured the wheel gauge on 5 cars that were in the shop for painting and/or weathering. Wheel gauge on two Lionel cabooses ranged from 1.197 to 1.215. Wheel gauge on three MTH boxcars ranged from 1.201 to 1.221. These are all narrower than @Norton recommends above. The plot thickens...
Ken, I think the main thing is to keep it under 1.250”. I am running on Gargraves track and that tends towards 1.260” or wider than 5 feet.
The thing is if the item is not derailing or wobbling around its probably OK. Or, if it ain’t broke don’t fix it.
Pete
@Ken Wing posted:Today, I measured the wheel gauge on 5 cars that were in the shop for painting and/or weathering. Wheel gauge on two Lionel cabooses ranged from 1.197 to 1.215. Wheel gauge on three MTH boxcars ranged from 1.201 to 1.221. These are all narrower than @Norton recommends above. The plot thickens...
Ken, to add to Pete’s comments, all of this junk is so mass produced, it’d be hard pressed to find consistent accuracies, ….I’ve measured dozens of wheel sets, drivers, etc, and never came up with the same number twice,……like I’ve mentioned above to necrails, that’s why 3 rail tire sections are sooooo wide, ….they make up the inaccuracies to get through a plethora of different brands of tracks,….including tube track,…..I wouldn’t rack your brain trying to accurately portray 3 rail gauging unless you run into a habitual offender that won’t make it down your pike…..
Pat
