Bachman SECR N 2-6-0

[williambarter]

Can anyone offer advice on how to convert the Bachman N class 2-6-0 to P4? Any published articles?

William

[David Knight]

William,

See the articles by Tim Shackleton in MRJ 111 & 112 under the title of Maunsell's Marvellous Mogul.

HTH

David

[Philip Hall]

William,

I ought to say a word or two here since I've done nine of these now, six EM and three P4 so I suppose I should know some of the wrinkles by now. I actually have three more P4 ones to do, two for myself, so it seems I am a glutton for punishment.

I followed Tim Shackleton's article but without the new tender he built (which you can get anyway now) and of course wheels with 3mm axles are readily available now. I never mess around with widening keeper plates (apart from adjusting brake gear), only widening the frames above that point. Sometimes frames are not widened for EM, depends what I'm asked to do, and to be honest it's not something you notice straight-away if it's not been done. I left the smoke deflectors alone because they looked OK to me.

I usually make up new return cranks from thickish brass, a basic fabrication to represent the injectors beneath the cab, pickups on the two outer tender wheelsets and some cosmetic widening and detailing of the pony truck, which seems easier to me than building a new one. Sometimes I cut away the close coupling housing for the tender, often I just hide it with the injectors - although I make up a new coupling hook glued into a hole at the back of the keeper plate, which hooks under the front of the tender. I use the Bachmann coupling rods, bushed with Alan Gibson conversion bushes and with the bosses slimmed down a bit, but ALWAYS check that the rod centres match the chassis slots. Often they don't and you will understand the results if you don't adjust things. Alan Gibson wheels for this are actually Midland ones, and the crank throw is much too small; the alternative is his 'Crab' wheel which has a greater throw, but still has the right number of spokes but with the crank in the wrong place.

I was supplied with some pictures of the SECR one, (P4) which revealed some precarious looking steps hung from the motion (instead of the later ones at the front) which were fun to make up and fix. On this one I went to town a bit and slimmed down the lamp irons, and added the piston tail rod covers which are quite prominent.

One final thing, when you've finished all this hacking about you might notice that the loco now sits a little too high, because you've fitted it with the right sized wheels; Bachmann's are way too small. There's nothing you can easily do about this because of the way the loco is put together. I am trying on one of mine, but it is a road I would rather have not started along had I known the potholes awaiting me.

Hope some of this helps.

Philip

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[JohnDC]

Phillip, or anyone else who could help please....

Having just purchased the latest Bachmann SR N class, can I assume that the Ultrascale LMS 17 spoke 13c/t Flowler wheels would do the job, even if they are not absolutely correct in detail. Or am I missing something?

Hopefully this will be easier than the T9!

John

[Philip Hall]

John,

I think the Ultrascale wheels would be fine. The crankthrow for a N should be 14", so 13" is pretty near.

Philip

[JohnDC]

Thank you Phillip. With your notes above and Tim Shackleton's article I have good advice so looking forward to this one, and running this lovely model.

All the best for 2013

John

[Philip Hall]

John,

Just a thought, do specify 3mm driving axles when you order the wheels - I don't think it's a common conversion for those wheels as they're LMS.

Philip

[JohnDC]

Phillip

Yes, thanks for the reminder.
I looked at Alan Gibson but their catalogue suggests that all drivers have 1/8" axles. That combined with the closeness in size of the Ultrascale wheel took me in their direction. Also, I've used them before and like what they do.

John

[grovenor-2685]

I looked at Alan Gibson but their catalogue suggests that all drivers have 1/8" axles.

As discussed on another topic on here just yesterday, AG do themselves no favours with the catalogue layout. Conversion wheelsets are listed on page 25, and the set for the N is at the bottom of that page and clearly specifies 3mm axles (Item 4800/20 which will be 4S00/20 for the P4 version).
Regards
Keith

[Philip Hall]

John,

Just another thought after Keith's post. AG do list a specific conversion set for the N, but it is a Midland wheel with a small crankthrow. This is what I have used many times in the past, but for the next three I have to do, two for me, one for a customer, I have decided to use the 'Crab' wheel, which has a greater crankthrow, closer to the 14" of the prototype, but with the crank in the wrong place (on the spoke rather than between). I took the view that you can't see the spokes when the engine is moving so prefer to see the motion moving a bit more. AG also do cast brass return cranks, but these too are for the small crankthrow, so you may prefer to do what I have done and make up your own.

The solution to navigating your way around the AG catalogue is simply to phone Colin Seymour with your order and tell him precisely the wheels you want - I hardly ever use the catalogue number!

Philip

[JohnDC]

Keith and Phillip

thank you both.

I thought it odd that only 1/8" axles appeared in the first list even though I knew that the model had 3mm. Now I have a choice. And I'll take a look at the reverse-cranks once I get to the conversion. There's always something new to test me!

Regards

John