Bachmann 45xx P4 conversion

[Hymek17]

I'm converting a Bachmann 45xx to P4 using Ultrascale wheels and the Bill Bedford Coupling and Connecting rod set.  I would be very grateful for any details and advice from anyone that has done this conversion, on how to fit the rod to the slide bar crosshead, along with what items I could use to fit the coupling rods to the Ultrascale crankpins, as the conversion kit is designed to use the existing Bachmann items.

 

Edited September 23, 2020 by Hymek17

[Captain Kernow]

I'd look to use a small nut and bolt for attaching the connecting rod to the crosshead, countersunk on the inside, and a small nut (16BA or perhaps 14BA) on the outside.

 

If the coupling rod holes are too small for the Ultrascale crankpins, you could try opening them out with a 5-sided broach. If the other way round, you could sleeve the crankpins (or the rods) with some suitably sized brass tube (available from Eileens).

 

[Tim V]

I used the original Bachmann coupling/connecting rods, and using Exactoscale bushes in the oversize holes.

 

There is a slight discrepancy between the centres, but this can be accommodated by jiggling the bushes. A very smooth running 45XX is the result.

[Miss Prism]

http://www.clag.org.uk/rtr-rod-fitting.html

 

(unfortunately, the Exactoscale bushes are no longer available)

 

[Tim V]

9 minutes ago, Miss Prism said:

http://www.clag.org.uk/rtr-rod-fitting.html

 

(unfortunately, the Exactoscale bushes are no longer available)

 

Gosh - I'd forgotten my article!

[Captain Kernow]

Surely you could find some brass tube of a suitable diameter to sleeve the crankpins (or to solder in the rods)?

 

Alternatively, perhaps some Gibson 'universal' rods could be made to to suit?

 

[Tim V]

Well, that was a waste of time replying!

 

Not even a thank you.

[Hymek17]

Many thanks for all your replies, much appreciated and a lot of ideas for me to follow up on. Sorry I did not reply sooner, but I'm receiving Chemo and have been feeling unwell since I put up the request and have only just seen all your responses.

[Hymek17]

19 hours ago, Tim V said:

Well, that was a waste of time replying!

 

Not even a thank you.

 

I've just read your article Tim, which was very informative. Sorry I did not reply sooner.

[Mark]

Gibson does bushes for reducing the bore of coupling rods to suit their crank pins. However the Ultrascale drop in conversion will have crank pins    with an outside diameter to suit the RTR rods.

 

Mark

[Hymek17]

Thanks Mark. I wanted to use the Bill Bedford coupling rods, which are not the main problem. It's the connecting rods which attach to the slide bar crosshead that are giving me the headache. The Bachmann ones are joined with a small cast in 'rivet' which is too large to fit the Bill Bedford rods. I don't know if those made by Markits will fit the Bachmann set up or whether anyone else had done the conversion and knew what bits worked OK. I'll have a look on Gibsons site to see if there is anything suitable as well It looks like I'll be having to try out a few things myself.

 

Thanks again to everyone for the information, it is much appreciated.

[hayfield]

On 25/09/2020 at 10:59, Hymek17 said:

Many thanks for all your replies, much appreciated and a lot of ideas for me to follow up on. Sorry I did not reply sooner, but I'm receiving Chemo and have been feeling unwell since I put up the request and have only just seen all your responses.

 

 

Hope you feel a lot better soon,  

[PenrithBeacon]

I have used AGW short valve gear rivets to articulate coupling rods with complete success.

[Hymek17]

22 hours ago, hayfield said:

 

 

Hope you feel a lot better soon,  

 

Thank you John.

[Hymek17]

21 hours ago, PenrithBeacon said:

I have used AGW short valve gear rivets to articulate coupling rods with complete success.

 

Thanks David, I'll look into these.