I have been asked to replace the plastic wheels on some Hornby Dublo coaches. The purpose is to enable them to run on Peco code 100 track with out hitting the chairs.
The biggest problem seems to be the deeply recessed axle boxes. Does anyone have any recommendations as to the best wheelsets especially in regard to these axleboxes, i.e. the most suitable pin point brass bearings.
At one time Peco produced replacement wheel that were intended for this very task, not having bothered to look at a Peco catalogue for many years I'm not sure if they still list the wheels - other than that you will need special bearings machined to fit into the axle boxes whilst the bearing surface conforms to modern axle standards. How many bearings are you going to need, depending on the number it might be worth contacting someone like Alan Gibson to see if he can produce the said bearings and what information / dimensions he would need.
If care was taken it should be possible to make non permanent changes to the Dublo bogies that would allow the original axle sets to be refitted if the need arose.
From memory the Dublo wheelsets (plain end axles/no pin-points) are held in place by holes in tin strips on each side of the bogie and do not use bearings in the bogie castings.
If Kevin can get hold of any modern wheelsets with similar axle ends (not come across any in years) he could simply use them as replacements for the original wheels. The problem is that to remove/replace the existing wheelsets requires at least one of the tin-strips to be un-tabbed with the risk of breakage when it is bent back to secure it in place. It would be very unlikely for this action to be repeatable (to replace the original wheelsets) due to bending fatigue these strips.
Well, when the Dublo coaches (3 rail) that we converted (many more moons than I care to remember...) were done I seem to remember that 'tin-plate keeper' you mention *clipped* into place, there is no need to bend any metal at all!
It would be preferable to put in wheelsets with both wheels insulated, otherwise you need to have the all wheelsets with the insulation on the same side AND plastic couplers because axles, bogies, chassis, body and couplers will all be at rail potential.
Hmmm, yes. I guess I was thinking of Bachmann-type wheelsets in which the centre of the axle is plastic but the wheels are not insulated from the pin-point ends.
Incidentally, you have to do the same as above with the EFE Underground trains if you want to motorise them and keep the original wheels, as only one wheel is insulated from the axle, which is held in place by a metal spring strip that is electrically connected to the diecast chassis. I replaced the non-powered wheels on mine with 9mm Romfords.
These particular HD coaches have a metal top frame for the bogies with plastic sideframes. The wheels are also all plastic, so I would assume that these are from the last production of these vehicles and are 2-Rail.
The plastic wheels are a pinpoint design, or at least they should be. They give the distinct impression of having been broken off a sprue by HD rather than having been filed later. As a consequence the existing wheels are a very sloppy fit in the bogie. Even so a 26mm axle is still fairly loose, so needs some bearings. The pin points bearings I have (being an EM modeller I know about these) are all no good as they don't allow the axle to go in the recess at all. I hope that bit makes sense.
Just thought, didn't Peco make some bearings for this purpose? I might have some, just a simple matter of locating them ;-)
These might be them, PR15. Do you have any in stock John?
From a Collectors point of view, forget them. Some have been permanently "modified" by fitting Kadee couplers to one end.
Many years ago I rewheeled some of my Hornby-Dublo coaches; the wheels/axles were by Jackson (I'm pretty sure - but could be wrong). If the bogie side frames were gently eased apart the plastic wheelset could be removed and replaced with the metal set. Unfortunately the replacement wheelsets were marginally longer than the original Dublo sets, so it was necessary to remove them, file a little off each end of the axle while maintaining some form of pointed end, and then pop them back in. When both axles spun reasonably freely the job was considered to be complete - all a bit "agricultural" by today's modelling standard but, nonethlees, it worked. The ends of the Dublo axles were rounded rather than pointed, so were not "pin-point" by any stretch of the imagination. Was it worth it? Yes - the metal wheels didn't pick up anything like the amount of muck the plastic (or were they nylon) did; the sound of the wheels on rail joints was enhanced and I still had what was then - and still is - a jolly good quality coach, albeit about an inch under scale length. By the way, the Dublo coaches cost all of 16/9d each (88p for those who can't recall proper money). Hope this helps, David Costigan
Kevin Martin wrote in news:43c47230$0$18228$ email@example.com:
As you go on to say that from the collectors pov these coaches are non starters might it not be possible to fill the old bearings with milliput then drill out to fit "modern" brass pinpoint barings suitable for "modern" wheels? Just a thought.