Hornby Pacific locos rear bogie

[paulbb]

On the Hornby Pacific steam locos, in particular the Britannias, Clans, and the Bullieds the trailing bogie on the loco is fixed with a flangeless wheel set. This looks less than convincing when moving on model railway curved track under 3' radius or so.

Has anyone modified this bogie to be flexible so it swings with the track, presumably fitting the flanged wheels that come with it as a substitute for the flangeless ones? It looks like bit of very delicate surgery to me, or is it straightforward?

The Bachmann solution for their ex-LNER pacifics is to make the wheel sets swivel within the fixed rame, which seems a cleaner solution to the problem of large locos on 'train set curves'  than the Hornby one.

[34theletterbetweenB&D]

Someone on here has described a conversion to a pivoting rear truck on the Britannia (will apply equally to the Clan) so hopefully they will chip in. I found that the flanged wheelsets wouldn't even fit in the Brit. truck, and had to cut clearance inside the truck casting so that the flanges didn't foul (examples bought when the model was launched in 2006). That done the Brit would manage the 30" minimum radius I require for main line locos so no further work was required.

 

The Gresley pacific models needed more work. The truck is a plastic moulding, and needed quite a lot of internal carving of both the central mounting post and the frame interior to allow enough sideplay for 30" radius. I made a fortuitous discovery, that if the rear bar between the frames is cut through then one can use the side frames to act as springs to recentre the wheelset. They have been running like this for over 10 years and the plastic hasn't fatigued, but they don't get that much movement on 30" radius.

 

Haven't fiddled with other Hornby pacifics. I'd like to, but the owners of the examples I have seen won't let me...

[Ben Alder]

Here is a link to what I did with my Clan - works fine with this mod.

http://www.rmweb.co.uk/community/index.php/blog/62/entry-1742-clan-gathering-at-kyle/

[paulbb]

Here is a link to what I did with my Clan - works fine with this mod.

http://www.rmweb.co.uk/community/index.php/blog/62/entry-1742-clan-gathering-at-kyle/

Many thanks Ben Alder, will have a try, and it should work for Bullieds too, possibly!

regards

Paul

[RFS]

There is already a thread about this issue here - http://www.rmweb.co.uk/community/index.php?/topic/127923-fixed-or-pivoting-trailing-trucks/?hl=cartazzi&do=findComment&comment=2916600

 

Being pedantic, the rear assembly is a pony truck not a bogie, as these have 4 wheels (or sometimes 6 on some coaches). And as far as the Bulleid pacifics are concerned there are two types: original Merchant Navies and rebuilt Light Pacifics have the fixed pony truck, whereas the original Light Pacifics and rebuilt Merchant Navies have separate pony truck.

 

But to get the separate pony truck to swivel properly, there is daylight under the footplate which is not prototypical, so there are pros and cons of each arrangement.

 

For the rebuilt Merchant Navy, the pony truck assembly is listed as a spare part with part number X8843. Whether that could be used in any conversion I couldn't say. 

[micklner]

A Cartazzi Truck on a Gresley engine.  The comment re the Bachmann design is correct , but to achieve the space for a "swing" the outside detail on the moulding suffers, being very shallow compared to the Hornby version.