|View single post by Si.|
|Posted: Fri Mar 9th, 2018 12:28 am||
|" what should the coupler height be from track top to bottom of the coupler "
There is actually really no 'correct' answer to that question.
I've never been able to find any info on that published by the 'San Juan Car Co.'.
However, that is probably because they assume several things :-
1. The coupler is being used as a replacement for an existing 'Kadee' On3 one.
2. The user has decided upon their own coupler height, to suit their own needs.
'Kadee' provide this drawing with their No.803 & No.807 On3 couplers.
The drawing is 'about' right for 1:35n2 generally.
The 5/8" railhead to car-bottom measurement, allows clearance for a 1/2" dia. wheel & flange.
My tendency would be to aim for a 8/16" or 1/2" railhead to coupler-center height for 1:35n2
The Evolution couplers are best mounted using an M2.5 machine-screw & above/bellow washers for adjustment.
Likewise, washers may be used on the truck fixing screw for adjustment of height there.
The bolster thickness can be varied as well, depending on what trucks you use.
I made a very simple coupler height gauge, from a block of metal, with a long M2.5 screw pointing upwards.
Washers & nuts can be added above & bellow the mounted test-coupler, to achieve your desired height.
What your desired height actually IS, may well change a bit +/- depending on . . .
Here's a pair of photos of the 'San Juan Car Co.' couplers mounted on 2 different underframe types.
There is a slight wide-angle lens exaggeration of depth in the photos, which were shot on a cellphone.
Wolfy the wolf, is in reality much bigger, even though he is only standing just behind the cars.
Wolfy is exactly 2" tall, which is equal to 4x of the 1/2" wheel diameters.
The left car, has 'beneath the frame mounting', typical of many cars inc. D.& R.G.W. and W.S.L.Co.
The right car has 'between the frame mounting', typical of the 'Gilpin Tram' stock which was built this way.
On both these examples, the axle-boxes & mountings are from modified 'Tri-ang' 4-wheel British wagons.
Here they still have the original 'Tri-ang' plastic wheels on stub-axles fitted.
I replace the 1/2" placky ones, with mooodern 1/2" metal wheelsets on pinpoint axles.
' Mysterious Moose Mountain ' - 1:35n2 - pt.II
' M:R:W Motor Speedway !!! ' - 1:32 Slotcar Racing Layout