Working / Sprung buffers

[Dave Cooper]

Not really sure where to put this thread but here goes :-

I do like things that actually work on my layout - not necessarily absolute, true scale, but just working...

One or two of my locos have sprung buffers and I thought it would be quite fun to have 'road-end' working buffers for them to rest into. So, I had a go at converting the Peco 00 'clip-in' buffer beams to take Bachmann sprung buffers. Not so easy ! the recesses needed for the sprung plunger coincide almost exactly with the rear diagonal support rails.

Score so far is one wrecked buffer beam and two seized sprung plungers where cyano' has crept into the moving parts.

Latest plan is to reinforce the beam /support interface and drill the recess clearance holes slightly 'off-centre'.

Just wondered if anyone else is mad enough to try this and how they got on ? As well as converting locos, I thought brake vans might be another candidate...

[Stephen Rainsbury]

What did you use for springs? Actual coils inside a tube or something like foam?

[B.Meldon]

The main problem with buffers on 009 locos and rolling stock is that you must either have a larger than normal gap between each vehicle or the buffers jam on the curves.
Having sprung buffers will help a bit, but the overhang combined with the curves will probably still cause them to lock up.
In the real world some NG lines do have side buffers, but the curves they use are far bigger than those we use in 009.
For example, the curves (and points) used on the Talyllyn Railway work out at 53-inch radius in 009!

[Dave Cooper]

Thanks for the replies:

Stephen - the Bachmann sprung buffers I have are miniature springs operating by a buffer/ plunger recessing into a metal tube. Any damping (which is what I think you may be alluding to with foam ?) is via friction within the mechanism. The actual spring rate is quite weak.

Brian - I'm really only considering 'end-of road' stopping at present as I have 'lost' quite a few wagons 'off-the end' through careless testing etc ! However, you make a good point about potential locking on curves. I'm just testing on standard gauge (00) at present, but, later on plan to go "single buffer" on 009 - am I likely to encounter locking problems here. The NG part of the layout has fairly generous radii curves so far ?   

[Dave Cooper]

Success ! I'm pleased to say that after a bit of trial and error, I now have two working buffer stops for platform and siding 'end-of-roads'.

Components used : Peco OO buffer stops (clip to rail type). Bachmann (LNER /SR) sprung loco buffers - not exactly scale but they look right...

Procedure I used: first reinforce the buffer beam to rear diagonal support rail. I used some scrap solid rectangular section sprue. This should be cyano'd (or similar) to the INSIDE faces of the beam making a snug joint with the rear diagonal brace. (It helps if you file down the scale rivets in this area first).   
Next, drill a 1,3mm pilot hole just outboard of the kit mounting pin and clean up this area with a file until the buffer beam is flat. Open up the hole to 1,7mm and check alignment both sides, adjust until parallel and square to beam. Final drill to 2,0 mm and try the buffer - the plunger should just clear the diagonal support at the rear of the beam.

Problems encountered : Buffer plunger too tight against rear support rail - use a small round file through the 2mm hole until clearance is obtained.
Buffer plunger stuck solid with adhesive : (I had two first time around) - soak metal buffer unit in switch cleaner overnight (I used Servisol). If stuck "in" - use two pairs of needle nose pliers, one on the outer cylinder and one on the buffer itself. Gently work to-and-fro until you get some movement. Repeat ad-nauseam !
If stuck "out" - get a piece of soft end-grain balsa and some hard, flat scrap wood. Using a small screw-type clamp, place one end of the buffer stop in the clamp. Pack BEHIND with the soft end-grain balsa and IN FRONT with the flat hard (against the buffer itself) . Line everything up square. GENTLY turn the screw on the clamp until you get some movement. Mine went fully home and stuck there !         

Was it worth it ? I think so, but then I like things that work... One other thing to watch out for is whether, or not, your couplings will fit through the gap between the front supports so that the wagon /coach /loco's buffers will actually 'engage' ! The Bachmann ones were fine, Hornby not. I haven't tried the others yet.

I see no reason why this could not be applied to 009 ? Single Buffer ?