Type of wagon coupling

[Lysardman]

I have built a small 00 layout for my grandson with curves at either end with an inner radius of 9.75 inches. The 0-4-0 engine manages these well if taken slowly. The problem arrives when a truck or two is attached by Hornby non NEM couplings. Even going round slowly they cause derailments. 

Does anyone have any ideas for replacement couplings that will allow them to work without derailments? 

 

[The Johnster]

If the NEM fitted stock manages it without buffer locking, then the answer is to replace the older couplings with NEMs.  This involves a bit of butchery and some internet shopping.  You will need a bag of Bachmann long straight NEM couplings from Peter's Spares, and a bag of Parkside NEM coupling mounts from Peco.

 

Remove the wheels from the wagons by gently prising them out; pull the axleboxes outwards to assist this.  Remove the old couplings; they can be simply pulled out unless the wagons are very old.  You now have to cut the plastic coupling mounting blocks away flush with the bottom of the wagon, and the easiest way to do this is to use a Dremel type power tool with a slitting disc.

 

With a coupling in the NEM mount and with another wagon to guide you, mark the position that the Parkside NEM mount needs to be glued to.  Also check that the coupling bars are at the correct height above the rail head and insert spacers or trim the top of the Parkside mounts to fit; this is important for preventing buffer lock and coupling bar override when propelling.  A dab of superglue secures the Parkside mount.

 

As it's only a truck or two, you must decide if it's worth the bother!

[PMP]

2 hours ago, Lysardman said:

I have built a small 00 layout for my grandson with curves at either end with an inner radius of 9.75 inches.

 

 This radius is much tighter than the smallest ‘regular’ set track 1st radius curve. It’s highly unlikely that any of the proprietary systems are designed to work below 1st radius curves which is partly why you’re having problems. It’s worth mentioning in case you’re not aware, that many contemporary locomotive, and some rolling stock releases are not recommended for use on radii less than second radius set track.

[DCB]

There is a breed of Hornby wagons with moulded plastic couplings integral to the chassis, If you have these I would stick them on eBay and buy something better as the hassle of trying to make a silk purse out of these is not worth the expense and hassle.  1960s/70s/80s Hornby with metal couplings should be OK but the wheels are rubbish. Luckily the later/ current wheels fit.

9.75" radius is tight.  Bekra models in Newton Abbott have a layout around 24" wide in 00 with curves nearly that sharp and they had a class 47 and Mk1 coaches operating when I was there last year. I am building, well thinking about it, its the thought that counts, a similar layout about 5 X 2 in 00 on a board formerly used for an N gauge layout,  I reckon as long as I stick to 4 coupled locos, maybe a short wheelbase 0-6-0  dock tank or a GW 45XX (Lima)  then it should work. Bad news for my A3 but I reckon i could make a passable 11" radius capable Ivatt Atlantic out of an A3 and a B12 with a bit of work with a hacksaw.

[Lysardman]

I have a Hornby GWR 0-4-0 ''pocket rocket'' running well on the system, though only at 30% speed, otherwise it shoots off the curves as you'd expect. I've removed the metal coupler pin from the  moulded plastic of the engine and replaced it by a bent paper clip, that can move across the whole of the moulded plastic bed,  to attach a 2 axle, short wagon and it seems to work both forwards and backwards around the bends at the speed shown.  It took a few tries to get the right length of the bent paper clip but what I have works so far.