What sort of tool do you use to measure wheel gauge on typical toy train 3 rail style O & O-27 equipment?
Original Post
Replies sorted oldest to newest
This is one tool. check here...
Originally Posted by DMASSO:
This one tool. check here...
I don't think that one does High Rail 3 rail wheel sets. If they get out of gauge they can be matched up with a set you know are good. But every set I ever had get out of gauge were bent beyond use.
The Lionel Service Manual shows a wheel gauge for the 622. It checks the back
-to-back distance with a steel block that is slotted to clear the current collector. The dimension is 1.100". i have also seen where they show the gauge being measured at the intersection of the flange with the tread. The manual states "The precise distance depends on the length of the locomotive and varies from 1.265" in Scout locomotives to 1.235" in 773 Hudson's." However I have never seen where they provided any gauge dimensions for other locomotives. The gauge dimension could easily be measured with six inch veneer calipers. I think most people let the length of the axle define the gauge.
I believe the 622 gauge is actually intended to position the collector assembly.
Lionel did not offer the gauge, it was up to the service station to make their own. The Train Tender had some made up (ST350-GT).
I use a pair of inside calipers. I think the slide calipers that AMCDave linked would work fine too.
I am either just old fashioned or a cheapskate, but for my HO equipment I just use my trusty dial calipers. I have never had to measure the wheels on my O gauge equipment. Recently did a wheel swap in an Athearn and the calipers came in handy there.
So, just to clarify, the NMRA O Gauge tool will, or won't work for 3 rail O & O-27?
The unit linked in the 2nd post will NOT work with O-27 3 rail trains.
quote:However I have never seen where they provided any gauge dimensions for other locomotives.
As far as I know, they did not provide dimensions. I just set my inside calipers before removing the old wheel, or if that is not feasible, I set the calipers against a different wheel set on the same or another identical motor.
As David said above, the axle sets the wheel gauge for the individual locomotive. The wheels are usually pressed on until the edge of the axle is flush with the outside of the wheel hub opening, and neither projects out of, nor is recessed in the hub. The wheel gauge may check differently on different locos. You should not need to measure the gauge if you have the correct axles and wheels for your locos. Our tinplate wheels and track do not adhere to the '0' scale model standards that closely; that is why the Standards Gauge cannot be used.
Larry
quote:The wheels are usually pressed on until the edge of the axle is flush with the outside of the wheel hub opening, and neither projects out of, nor is recessed in the hub.
That may hold true for prewar tinplate trains. I don't think it holds true for postwar. The Lionel service manual warns the repairman to get it right.
Here is a page from the general motor service section of the Lionel service manual: page.
Folks looking to work on their own trains would do well to read the motor service section. They might pick up some good basic information on repairing Lionel trains. For years this information was difficult for consumers to obtain. When Aurotec published the first reprint of the Lionel Service Manual, it was a boon to those of us interested in repairing Lionel trains. Now the entire manual is online at Olsens.
The wheel gauge figures given in the service manual seem to apply only to the Scout and 773 Hudson locomotives. There does not seem to be any precise standard for the rest of the locomotives. If you wish to measure the wheel gauge back-to-back before removing wheels to aid in reassembly, that can be done. Lacking calipers, and the lack of a precise gauge standard applicable to all locomotives, the method I have described works well, and I have had no problems with locomotives not running properly passing through switches, going around curves, etc.
Larry
As I mentioned earlier, and inferred in the Lionel service manual, either measure the spacing before dis-assembly, or take a measurement on a like engine.
Here is a quote from the service manual page I referenced above.
quote:When mounting wheels be careful to maintain the original distance between the wheel flanges. The precise distance depends on the length of the locomotive and varies from 1.265" in "scout" locomotives to 1.235" in 773 hudsons.
Certainly we are all free to repair our own trains as we see fit.
A set of calipers is only a few bucks for a serviceable set, so I'd consider buying them. 
If you're willing to go to the trouble of standardizing all your wheelsets, consider this:
In the NMRA Standard the "K" dimension is an interesting dimension. It is from the gauge point to the opposite back side. Someone must have a custom gauge that makes use of this. No where does it actually give the wheel set gauge, but it is easily derived by adding the back-to-back dimension to two flange thicknesses. Te standard does not identify the gauge point on the flange, but if the Lionel gauge point is used, it is easily found.
On real wheels the back-to-back distance is the critical one as the track frogs and guard rail interface is critical. The wheel set gauge is usually about 3/4 of an inch less than track gauge.
Since most of us run curves much sharper than 20 degrees, I would suggest sticking with the OEM's wheel gauge unless there is a problem that needs to be resolved. My experience is that derailments related to wheel gauge are usually a result of a loose wheel or a bent axles.
