N Scale Kits 89ft flats - couplers body mount or no?

[craigolio1]

Hello all. 

I just received my first two N Scale Kits 89ft flat car kits.  They look like spectacular models. I'm modelling a mixed passenger train and I'm wondering everyone's thoughts on where the couplers should be mounted?  For those who don't know the kits are designed either for a body mounted coupler, or a MT 1019,   

https://www.micro-trains.com/index.php?_route_=n-scale/magne-matic-couplers/unassembled-coupler-for-tm-or-bm-on-tofc-s-1019-2pr-00102008.

For my passenger trains I've been body mounting couplers and these trains primarily run on N trak modules at shows, however in this case the 89ft flat cars will be sandwiched between a 50ft boxcar and a 56ft flat car.  I'm concerned that if I body mount the couplers, the mismatch of the length of cars, and there for the coupler position in turns /s-curves, will cause derailments.  In the case of the 1019 any forces are applied to the bolster vs the truck, so I'm thinking that I will have less issues if I use the 1019.

Anyone have any thoughts?

Thanks.

Craig

[altohorn25]

I body mounted all my 89' MT flats and haven't had any problems.  That being said, I believe that is a different coupler; I snipped the truck mounted ones off that were already on the flat and body mounted them.  I'm pretty sure they are not 1015's.  I haven't tried running them on an Ntrak layout, but they run fine on my home layout (19" radius curves) as well as the modutrak layout.

[rapidomike]

I personally can't stand truck mount, so I body mount everything. I've done it on Aluminum autoracks from Kato, I believe those are 87' long.

As long as you have the radius for it, I'd say do it. My autoracks run well on anything bigger than 14". The small test loop in my office is 12", and they like to derail on that.

[peteski]

I woudl say that this will depend purely on the minimum track radius on your layout.  These cars are very long and the trucks are inset quite far from the ends, creating very large overhang on tight curves.  That is why the couplers are mounted on long swing arms.

While a car-to-car connection would likely not be a problem, the 89' body mount coupler flat car coupled to a shorter car or a loco will likely cause problem on tighter radius curves.  Easement curve would help but it might still be problematic.

[randgust]

I have 13" minimum radius on my visible mainline, 11" on my hidden track, and a train of 14 89' piggyback flats through that and up a 2% grade. It's a mix of MT, BLMA, N Scale Kits, and Trainworx cars.

I have both body-mount and truck-mount cars.  It's all about coupler swing.  The only complete fails have been the Atlas cars with cast-on boxes, just not enough shank length and they stringlined.  But the other bodymount cars have worked OK.  I have truck mount 1019's on my N Scale Kits cars, those are really heavy and I have to run them at the front of the train.   

If you are going to use bodymounts, consider a 1016 longer shank, maybe mounted back a bit, rather than a 1015 box.  That would make a difference to get the coupler pivot point back a bit as well as have a better side swing.

Also check your coupler heads for the RDA modification or do it yourself.  That's the only way to make truck mounts center-up properly (vertically) and not pull apart under heavy load.  Most of the grief from MT's in general comes from that.   Any car like a piggyback or autorack with the coupler 'out there' is going to have more issues with the vertical alignment that will cause pull-aparts if the heads are not RDA.

[jagged ben]

The 1019 is a replacement for MT 89' cars and is an 'underslung' style, meaning the knuckle is raised relative to the draft gear box.  If you're going to body mount you probably want to either cut the 1019 off the swing arm or use 2004, which are essentially the same coupler without the swing arm.   A 1015/16 will have the knuckle too low which will cause couplers to come apart.

With the extra weight of those N scale kits cars you have more leeway to body mount and not have problems (although coupled cars that are lightweight could still experience problems on tight radii). 

[MetroRedLine]

The 1019 is a replacement for MT 89' cars and is an 'underslung' style, meaning the knuckle is raised relative to the draft gear box.  If you're going to body mount you probably want to either cut the 1019 off the swing arm or use 2004, which are essentially the same coupler without the swing arm.   A 1015/16 will have the knuckle too low which will cause couplers to come apart.

With the extra weight of those N scale kits cars you have more leeway to body mount and not have problems (although coupled cars that are lightweight could still experience problems on tight radii).

To address the OP's concerns, body mounting works if you have 15" radius or higher curves. Anything less and you're better off sticking to truck mount.

The reason why these couplers are underslung is because MTs are either placed on a truck extension or in a draft gear box on the underside ends of a car. However, the prototype has the coupler embedded into the central spine of the car, which is a position that's higher than any bodymount or truck mount coupler can reach. I'm not too familiar with the N Scale Kits cars, but if they have their bodies made so that the coupler is longitudinally aligned with the central spine of the car, then an underslung coupler would be too high for this car.

[jagged ben]

...

The reason why these couplers are underslung is because MTs are either placed on a truck extension or in a draft gear box on the underside ends of a car. However, the prototype has the coupler embedded into the central spine of the car, which is a position that's higher than any bodymount or truck mount coupler can reach. I'm not too familiar with the N Scale Kits cars, but if they have their bodies made so that the coupler is longitudinally aligned with the central spine of the car, then an underslung coupler would be too high for this car.

I think that the reason they made them 'underslung' is that the standard MT coupler height is unprototypically high, and this becomes really obvious if the draft gear ends up above the deck of an intermodal flat car.  So they had to lower the draft gear.   I figure for the autorack they could have done it differently but chose to re-use parts.  Oh, and back when they designed those cars people really expected truck mounts, so to swing back and forth the draft gear needed to be under the deck, or else there'd be no meat to the end of the deck and that would look weird.

When BLMA and Atlas designed body mounts for 89' flats, they recessed the coupler pocket into the deck much more prototypically.