John Cutler
Andrew, you may not like this…..
I recommend:
1. Start by converting the 64xx to EM. Buy a set of 3mm axle Markits or Alan Gibson wheels.
2. If that conversion does not result in a smooth-running loco, try and ascertain if pick-ups are the problem. If so, consider acquiring a Bachmann autotrailer, which has pick-ups fitted for lighting, converting it to EM and connecting it to the 64xx.
3. Consider upgrading the 64xx by building a High Level Kits chassis to go under it. Note that you will need gears and a motor as well but the excellent standard of the Bachmann body justifies the extra cost in my opinion. You could re-use the wheels from the first conversion (but personally I would not do so); if so ask for 3mm axle bearings from HL when ordering.
4. The current Dapol 14xx is, I think, the same as the old Airfix model. If so, the body needs a lot of work to bring it up to today’s standard; refer to Iain Rice’s article in MRJ1. Wizard Models sell his detailing kit MT222 for £24.00 which I recommend. I tried twice to build the Perseverance compensated chassis for this but both attempts resulted in unsatisfactory running; it was a pig to get right! I suspect the current Comet chassis from Wizard is also a challenge. The High Levels chassis kit is probably the safest option but at a much higher cost. You may well ask why I have not gone down this route. Well I am fairly sure I cannot produce a sufficiently high quality body and paintwork to match the standard of the HL chassis (yes, I have a chopped-about Airfix body and detailing kit in the Forgotten & Neglected section of the storage boxes!). Will all the work and cost be worth it? Be careful. Unless you like a challenge, I think this project could end up being demoralising. Maybe you should wait for the new Dapol tooling expected at the end of 2025?
5. For an easier GWR conversion, try a Bachmann 8750 or 57xx. Face it, there were hundreds of these panniers on the Western so you probably should have one anyway! Lots can be found on the second-hand market.
6. The Dapol GWR 43xx mogul looks good. The outside cylinders will present a new conversion challenge for you but at least there is no complicated Walschaerts valve gear! The Dapol chassis is supposed to be compensated and has a sprung pony truck so worth trying a simple wheel conversion. Add pick-ups to the tender if they are not already fitted. Remember to write up your conversion to EM on this forum or as a Manual Sheet in case I decide to buy one!
Good Luck!