Hello all! I'm new to this forum, though I've been rail modeling for a number of years now. Took a two year hiatus from the hobby, and I'm just getting back into N Scale. My name is Andrew. I have a question, right off the bat: I don't remember having this problem when I modeled N Scale a few years ago, and this MTL Coupler Height Gauge is a few years old but I can't imagine the standard has changed. I am preparing to convert my freight cars to body-mounts, and wanted to do some pre-checks with the coupler gauge... I've found, though, that the gauge says all of my MTL truck-mounted couplers are too low.... I tested with low-pro wheels and pizza-cutters. Pictures added. What am I missing?
My gauge, acquired several decades back, also shows the same way. I cannot recall ever having a problem because of this difference.
Fair enough.... Then which height should I set my body-mounted couplers at? The couplers on my locomotives are at the same height as the trucks. If i set my freight couplers to the locomotive coupler heights, I should just use an MTL truck as my standard... In which case this gauge has no purpose.... I feel like the difference is pretty significant considering the height of the coupler will play a big part in determining how much to lower my freight cars... And the height difference seen in the pictures will have a large visual effect on the overall appearance of the cars.
The difference you show is minimal. You will find more differences than that between manufacturers. I have thought for a long time that truck mounted couplers sag a bit. Do you get the same difference when the truck is mounted to a car. The coupler weight will cause a truck to tip because of the slop of the axles in the truck, expecially when it is by itself as in your picture. The size of the flange (lo-pro vrs. pizza cutters) will not make a difference cause the wheel is the same size. I have some of the new Micro-Trains passenger cars with body mounted couplers (direct from MT) and they match up with the gage exactly.
I've checked most of my MTL trucks against the gauge and they are all at the height shown in the picture, even those mounted to a freight car... I just think it's strange that the same company's truck-mounted couplers and coupler height gauge disagree with each other..... No matter, though: As stated I'm going to use an MTL truck-mounted coupler as my height standard for all body-mounting.
I can't lay my hands on my gauge but recall it has to be pushed down on the track hard, not just set on it. Trucks work just as well, eaiser to find. Bob.
I have never had this problem with my old, old gauge. Looks like the coupler box might not be fully seated in the gauge. Al
This is not an issue I have encountered before and as Mr. Horn stated the gauge does need to be pushed down solidly on the track. The next question is the coupler in the gauge the one that originally came with the gauge and is it properly set into its recepticle. The coupler should be absolutely flush on the top with the metal for the entire coupler length. Also as a last thought you might have a defective gauge or coupler in it. I have two gauges and looking at your 2nd photo it appears that the coupler in the gauge is setting just a tad high. Looking at both of mine from the side at eye level you don't see anything but the mounting screw for the coupler box. The box top is flush with the metal top. I would want to check for flash on the coupler and against another coupler gauge. Could have been a milling issue at the factory. Just because it is supposed to be a precision instrument doesn't always mean it is. I have three different N scale rules that are supposed to be precision. Yet all three tend to have discrepancies at the longer measurements.
Smaller flanges make no difference, the diameter of the wheel (which contacts the rail) should be the same
Mine is identical in how it meshes with the truck mount coupler. Even when firmly pushed down on track. The coupler is seated solidly in the metal base. I have had it apart to check for flashing, etc, and it is clean.
I have seen this difference as well, and my gauge is definitely sitting correctly on/between the rails, and has the original coupler factory installed. The MT literature says the mid-line of the coupler should be 0.216" above the railhead and my measurement of the coupler height on the gauge was closer to .226", which is pretty consistent with the OP's photo. The truck-mounted couplers I have with factory fresh MT 33" wheels are very close to the standard, so I would stick to matching the truck-mounted coupler height. I can't explain the gauge. I encountered this when I started body-mounting Z scale couplers, where a difference of 0.01" can be significant. FWIW, the prototype standard is 34" above the railhead, and 0.216" corresponds to 34.6", which is pretty much bang on. -Gary
I gave the gauge a once-over and rebuild for the sake of being thorough, but to no avail. Since it seems I'm not the only one with a too-high coupler gauge anyway, I've just set aside some trucks as my height standard. The gauge has disappeared into some box over there.... Thanks for the input guys!
I wouldn't have a problem with milling the coupler height gauge to correct its problem. Easy mill...VOILA! It's fixed.
