Coupling for Lima locos

[barney121e]

I have some Lima diesel locomotives and dmu's. What could i do to improve the couplings on them?

 

Cheers

 

Dave

[The Johnster]

Pretty much anything!

 

Ok, here's what I'd do; others might have different and better ideas.  I'm assuming you want to stay with the tension lock format but do better than the oversized hideous excrescences that Lima used by using NEM tension locks.  These are a huge improvement over Lima tension locks, much less visually intrusive (let's be honest, an armoured division painted in dayglo orange on acid wouldn't be much more intrusive), and allow smaller gaps between the buffer heads of adjoining vehicles

 

The Lima monstrosities are mouled to the bogies, and have to be cut off; Xuron track cutter, wire cutter pliers, or small snips.  Between vehicles on my antediluvian 117, which I converted many, many, years ago now to a 116 (took an extra DMBS and an extra TCL, but they were cheap as chips in those days), I made my own hook and link semi-permanent couplings using bent to shape staples (Rexel no.14).  These are attached to the bogies by a lump of Milliput and a touch of superglue; lay what has now become the shaft of the coupling over the crosspiece at the end of the bogie frame and trap it with the lump of Milliput, then glue it for permanence.  A better engineering solution is to drill a hole horizontally through the crosspiece and glue the shaft into that. 

 

Now, you need to decide whether you need to couple dmu sets together or have them hauling tail traffic.  I didn't, and fitted scale screw couplings, the twin pipe vacuum brake system's hoses, and control cables at the cab ends, along with scale buffers which hugely improve the look.  My 116 is 40 years old and still gets an occasional outing; once cleaned it runs very well down to a crawl with the controller only just delivering volts, and the hook'n'loop staple couplings allow reliably propelling, essential with a dmu.  Scale buffers are a very worthwhile improvement in the appearance of all Lima stock, and much of contemporaneous Hornby stuff as well.

 

For NEM tension locks, Hornby or Bachmann will sell you bags of 10 for about £12 these days; hope you haven't got too many vehicles to do!  NEM couplings come in 3 basic parts, the coupling itself, the box, and the mount.  Bachmann sell the coupling with the box; not sure about Hornby.  You will have to devise how to mount the couplings on the stock or locos yourself; it is critical that they are compatible with the rest of your stock in terms of height and distance protruding beyond the buffer beams, and this is sometimes a bit fiddly.

 

On your dmus and locos, the couplings have to be mounted to bogies, which makes things even more awkward, but a bit of bodgery and ingenuity will see you through.  Starting with the mounts, plastic pieces which have a dovetail cut into them to accept the vee-shaped piece on the back of the box, which I call the waggler, these are available, also in packs of ten, from Peco Parkside, part no. PA34.  The joy of these things is that they are made of a fairly soft plastic, and so can easily be trimmed down with an Exacto knife to allow the coupling to be mounted at the correct height; if the coupling is too high above the railhead, you can glue a packing piece of scrap plastic to bring it down.  Don't make the mistake I did, the height of the coupling bar has to be to a standard measurement above the railhead, which is not the same as a standard measurement below the buffer beam...

 

But it will probably not be possible to use these PA34 mounts on most bogie stock where the couplings are moulded as part of the bogie.  Alternatives will be to either glue the box to the bogie frame and then insert the actual coupling, or in some cases to glue the coupling directly to the bogie.  You will need to cut a slot in the front of the bogie and cut the beetle antlers off the coupling, which leaves a plastic tab about 2mm long behind the hook pivot.  You can then glue the coupling into the slot. 

 

If there is no alternative, you may have to attach the coupling to the loco body.  On long locos like Westerns, there is a possibility that sharp setrack curvature will cause derailments if the coupling has no sideplay, but you should be ok if your minimum curves are 30" or larger radius.  Westerns and Warships have front body fairings that make fixing the coupling directly to the loco body the only option other than wire bars.

 

Some people use simple wire bars on the ends of locos and dmus, for the hook of vehicles's couplings to engage over, but I don't recommend this for propelling.

 

If you want to dispense with tension locks altogether, then Kaydee couplers use the same NEM box and mounts, so the same comments apply.  Automatic couplings like Sprat & Winkle or Dingham, and scale couplings, are the better options from the point of view of scale appearance, but need large radius curves and softly sprung buffers, especially if propelling or shunting is to be accomplished.  But they have the major advantage that they can be correctly mounted to the buffer beams rather than on the bogies.  With scale couplings, you can cheat by mounting the drawhook a half millimetre or so further out from the buffer beam than it strictly should be; this dodge is barely noticeable and allows slightly tighter curvarture, but you are still pushing the buffer lock envelope if you go under 36" IMHO.

[Sasquatch]

Another option might be to try the Bachmann screw on types 36-025 & 36-026. These are marketed as replacements for early Bachmann rolling stock but will fit most Mainline & Replica stock also.

Only trouble is, they don't come with the screws. Suitable screws can be found on eBay etc.

I have found cutting off the wings of the mounts sometimes is necessary and super glue works well too. Thus...

Just remove the loop on the Lima bogies leaving enough plastic to mount the replacement on and drill a small pilot hole to accept the screw. The side-to-side motion provided by NEM mounts is only really needed on stock with long over hangs such as CCT vans and layouts with tight curves. 

When replacing tension lock couplings on any stock the rules to follow are approx. 9mm from rail top to hook shaft and somewhere around 2-3mm beyond the buffers. More if you have 1st radius curves!  

 

Good luck!

[F-UnitMad]

19 hours ago, The Johnster said:

Pretty much anything!

Agreed!! Those old Lima tension locks weren't nicknamed "Volvo bumpers" for nothing....

 

Volvo bumper:-

 

Lima coupling:-

 

....and yes, I meant to post the photos that way round! 😉

[colin55]

Check out this Ebay seller. He's developing coupling replacement mountings

 

https://www.ebay.co.uk/sch/mattymay05/m.html?item=202772112519&rt=nc&_trksid=p2047675.m3561.l2562