Hey Rusty...

Hey John.

 

Based on what I know of the earlier PRS ACF covered hopper, the hopper chutes, bottom and sides are one piece, with the roof and ends as separate pieces. I'm not sure how easily the roof on the SSA car will come off, depends on how well it's glued on.

 

I s'pose on a SSA car, it would be easiest to add some kind of shaped weight up between the hopper chutes.

 

Generally, I don't add extra weight to anything already built, but the SSA covered hopper does strike me as being a little on the light side.

 

When I build a kit, I usually add a ounce of weight (maybe 1.5 oz, it's been a while..) inside above each truck, favoring the sides rather than the centerline.  Most of my 40' and 50' PRS boxcars are weighted that way.  (Although, I have one 40' boxcar with no weight added, save for the metal wheelsets, it's never given me any trouble no matter where in the train it was located.)

 

Rusty

Ed, thanks for a well thought out response!
Yes, no derailments is the goal.  In the 5 years I was in 2 rail O scale, never had a derailment due to trackage, etc.
My road has 2 sharper 30" radius curves out of available space.  While not desirable, they smooth and level.
Only cars/trucks that give me gas are SHS PS2 bay and 3 bay hoppers.  Seems often that trucks are not 'square' on the track.
As mentioned, SSA cars need clipped bolsters as Rusty mentioned, in addition to weight.

>> Only cars/trucks that give me gas are SHS PS2 bay and 3 bay hoppers.  Seems often that trucks are not 'square' on the track.

 

When I "process" cars before putting them into service on the layout, I will place them on a perfectly flat surface (glass, etc.) and make sure that all eight wheels touch the ground.  If they don't, then it is time to fix them before running them. 

 

I am not sure if this is what you mean by "not square", but if the wheels do not all touch the ground, then derailments are probably more likely. 

 

Fixing that situation might involve filing rough surfaces down smooth so that the trucks truly equalize.  Or, it might involve replacing stiff springs with softer springs to improve equalization.  Or both.

 

In the case of the first production run of SHS PS-2 covered hoppers, the truck side frames canted inward and caused rough riding (to put it mildly).  The fix is to wedge a short piece of wood between the lower edges of the sideframes to spread the side frames apart just a bit.  Glue the wood in place and paint it  black and it is not noticeable.  After this fix, the car rolls nice and freely.

 

Hope this helps.  If you could be more explicit about what "not square" means, maybe there is some other fix for it  (whatever "it" is).

 

Rolling along.........Ed L.

Ed, as usual, you hit it 'squarely' on the head.
Another thing that helps "realism" in our model DCC world are capacitors that keep the locos running thru dirty track.
And you are very correct in stating "realistic slow speeds".  A pet peeve of mine, when you see trains jetting around the layout...
It an't Indianapolis, IMHO.

FWIW:

 

Empties vs loads placement in trains:

 

The prototype has the same problem: Empties on the head end with many loads to the rear on a long train being switched can cause the train to "string line" on a curve or going up a heavy grade. (i.e. the heavier cars on the rear pulled the lighter cars off the track.)  This can also happen on a shoving movement through a curve, but this time you can push the lightweight cars at the head end off the track with too much buffer force.

 

On the railroad on which I work, we had an example of the latter just a week or so ago. (Nope, wasn't me twiddlin' the sticks.)