Wagon springing

[2188]

I'm attempting to spring some plastic wagon kits using Dave Bradwell's spring plates or possibly Chris Pendleton's technique soldering wire springs to 'TopHat' bearings.
However I'm having difficulty accurately slotting the plastic axle boxes on W irons, what's the secret please?
Thanks
Mark

[grovenor-2685]

Sorry, I don't know of either of those techniques, but there are really only two options if using sprung bearings in fixed W irons.
1. Use the shouldered type of bearing to minimise the size outside the W-iron, recess the axlebox so that the bearing has room to move without the axlbox needing to move. The axlebox can be hollowed out with a drill which will often allow enough movement, or if an oval cavity is needed to give more clearance then a round ended burr in a minidrill does the job.
2. Use full 2mm bearings and fix the axlebox onto the bearing so that it moves up and down with the bearing, this requires the bearing to be seperated from the spring, or the spring from the hangers in the same way it is done for rocking W irons in compensated systems.
Regards
Keith

[Tim V]

Assume you have referred to Chris' article in MRJ?

[Guy Rixon]

I find problems in accurately fixing the axlebox to the axleguard after opening out the cavity in the box. If the box is displaced by ~0.2mm laterally the edge of the cavity can foul the bearing. I use a very small burr in a minidrill to finish expanding the cavity after fixing the box. The burr has a neck behind the cutting part and I run the neck against the slot in the axleguard. This gets me a fixed width of cavity measured from the edge of the bearing.

[Russ Elliott]

I usually make a complete hash of opening up the backs of axlebox castings/mouldings. Before proper sprung W-iron systems were available, here's what I did on a couple of ABS wagons, which worked ok.

axlebox-cavity.png

The axle bearings slide up and down the added wires. Springs were soldered to the outer flange of the bearings. If using cantilever springs in 'spring-assisted' mode, as I was, the problem is constraining the upper movement of the bearings, and I arranged a 'stop block' inside the face of the solebar, but it was an awful flaff to set the ride height properly, and I'm not convinced it was worth the effort compared to using a modern type of sprung carrier system. (I don't think I would adopt the method again.)