Help with Converting Dapol Siphon H to P4

[John Fitton]

I have a Dapol Siphon H which I think should have GWR 9 foot bogies. However, when I attach the Brassmasters units with what I think are ABS white metal cosmetic sides, the ends of the bogies protrude about 2 - 3 mm beyond the buffer beam, and the inner ends interfere with the trussing. I dont have any drawings of the Siphon H. I have converted a couple of Lima Siphon G models and although things are a bit tight they look and run well. Any help would be appreciated.

John Fitton

[Noel]

There is a drawing of Dia O12 o/s framed end door Siphon in the HMRS GW Siphons book by Jack Slinn and Bernard Clarke, plus separate 7mm scale drawings of the bogies. There are also various photos, including detail ones of the various bogies. The book shows them as built with 9ft coil sprung bogies at 35ft centres on a gas lit 50ft angle-trussed underframe, which appears to be identical to that for the post-WW1 Siphon G. The last 3 built had 9ft American bogies, to which many of the others were converted circa 1929/30. A few were changed to 7ft heavy bogies at a similar time.

Noel

[Bulwell Hall]

I had the same problem but to a lesser extent when I built this Siphon H recently. Using an ex Mainline body on one of my chassis kits the requirement was for the model to be built to P4 with sprung bogies. I used Masokits sprung bogies and a set of cast whitemetal cosmetic bogie side frames for the 9ft 'American' bogie from David Geen - as may be seen there is a missmatch in the length of the bogie sub frames and the cosmetic overlays. Due to the design of the sprung bogies I could not see how I could reduce the length of the bogie sub frames so the result is a compromise which may or may not be acceptable. Other than scratchbuilding some sprung bogies - which was not in my remit - I could not see how to overcome the problem so the result is as shown. The model was built along with a Siphon G - which also has the same compromise - and both are now with their new owner in New Zealand.

Gerry