Making an Edwardian 3111 Class Large Prairie from an Airfix 6110

[Dana Ashdown]

Large Prairie No.3113 — final instalment.

 

 

Most of what you see was actually finished at the end of April (the lining was done on a rainy Sunday), but there were still a number of little details left to do and, thanks to Covid and the garden, these took longer than expected.

 

 

As you may remember, the front footplate was NOT level!!! It didn’t look too bad in real life, but it showed in the photos. I should have done something about it before, but it was very well fixed to the body (which is a rather thin moulding) and I was afraid of major breakage if I tried redoing it. Then I had an idea:

 

If I cut through the thick piece of plastic that forms the base of the front footplate, leaving the thinner part on top intact, I could bend the footplate down and re-glue it at the correct angle. The thin top effectively acts like a hinge. So, with my larger razor saw (I needed a wider kerf for this), I sawed almost completely through the thicker plastic base until the footplate could be flexed. With some glue spread along the kerf, I push the footplate down until it was more or less level with the rest of the engine, and put a small weight on it until it had set. I did this with the body fixed to the chassis, using the fronts of the cylinders as a guide. A tiny gap was left on the bottom of each side of the footplate as a consequence, but nothing to be too concerned about.

 

For the present, the front footplate seems reasonably strong, but I have this odd feeling that in about three or four years  it may need struts. Don’t ask me why.

 

 

Etched plates would have been nice, but this is a budget project, so I made the number and builder plates from scraps of thin plastic sheet. For the number plates, I painted the plastic black; when dried, I applied two number plate outlines from the HMRS GWR lining sheet, and then added the numbers from the HMRS GWR locomotive and coach sheet. Although the numbers are the right size, they are not in the correct font. The number plates were then varnished, and finally cut out and filed to size. The white edges were done over with a gold Posca pen. I think the plate on the right turned out better than the one on the left side.

 

The builder’s plate, such as it is, was done by painting a piece of plastic with Humbrol brass paint, then cut out out and shaped with a file. This is actually the second plate. I also did a piece using the gold Posca pen, which actually had a brighter, brassier look to it. This was the one I did first, but apparently Mr. Churchward did not approve and snatched it from the tweezers just before I was going to glue it in place. I saw it fly off, and still haven’t found it! So, out with the other piece with the Humbrol brass paint on it, and after cutting and filing to shape I glued it in place. I made no attempt at putting any kind of printing on either one.  Anyway, Churchward was right… the second one does look better. (As luck would have it, the cameras picked up a whitish reflection off some errant glue just above the plate.)

 

I wasn’t sure about adding the sandboxes inside the cab, but as they are fairly obvious on the  prototype, I thought I better do them. The whistles were made from the front footplate handrails of the original Airfix engine. I did make wheels guards for the pony trucks using some scrap brass, but they came off. The plastic on the front truck seems to resist the Testor’s glue, so I’ll have to try some epoxy. On the rear, I had to modify the truck so there’s no longer any place to fix the guards to.

 

 

 

 

So far as running is concerned, the engine has been in its box for several decades. I didn’t expect any miracles, and I was not disappointed.

 

One issue that arose was the engine’s tendency to spin its wheels. This was traced to the rear pony truck. Having installed larger wheels of the correct diameter at the beginning, the truck sat higher than it did originally. Since, the rear end of the truck comes just under the buffer beam, it caused the rear of the engine to lift off the track. Not by very much, but enough to cause the wheels to slip and spin. The solution was to bevel off the top rear corner of the truck so it cleared the buffer beam. This part is die cast metal, so I used my hand-powered grinder for the job, but files would do as well.

 

 

I was worried that painting the piston rods, crossheads and guides might cause some binding, but so far it doesn’t seem to.

 

However, the electrical pick-up is a problem. All six drivers have pick-ups, so you wouldn’t think there would be an issue (although the right rear wheel has a traction tyre). Applying power directly to any of the wheel sets puts the motor in motion, so that seems fine. And yet on the test track it frequently hesitates or jerks, or refuses to move unless its wiggled. I’m not sure if the coupling rods are binding, or if its just an electrical issue. Some running-in time certainly wouldn’t hurt.

 

When it has a mind to, it can pull at least eighteen wagons with ease, which I gather is more than the modern Hornby and Dapol 6100 Class Large Prairies can do. That said, a current Hornby or Dapol 6100 Class Large Prairie might still be a better platform, especially for a 3150 Class conversion.

 

Although No.3113 is obviously a compromise, I think it turned out rather well. But we really do need a modern RTR model of either the 3110 or 3150 Class in original form. For me, the 6100s are just “too modern.”

[33C]

Sounds like the pick ups need tweaking to run firm and flat against the rims. Great job by the way!

[Mikkel]

That's beautiful Dana, and quite an eye-opener too. I've always felt the large prairies looked a bit awkward but in this condition with this livery it's a very attractive loco.

 

 

[DCB]

On 22/06/2022 at 18:35, Dana Ashdown said:

 

However, the electrical pick-up is a problem. All six drivers have pick-ups, so you wouldn’t think there would be an issue (although the right rear wheel has a traction tyre). Applying power directly to any of the wheel sets puts the motor in motion, so that seems fine. And yet on the test track it frequently hesitates or jerks, or refuses to move unless its wiggled. I’m not sure if the coupling rods are binding, or if its just an electrical issue. Some running-in time certainly wouldn’t hurt.

The 61XX with single traction tyre picks up through the trailing truck wheel immediately behind the traction tyre as only one wheel is insulated.   With both insulated it can stutter.   I used replacement see through spoke wheels, Jackson probably and I de insulated mine by putting very thin wire down the inside and back down the outside of the insulated bush and pressed the wheel on the axle before  trimming the ends. I also added a thrust washer super glued to the wheel so the wire didn't wear too quickly. 

[Dana Ashdown]

19 hours ago, DCB said:

The 61XX with single traction tyre picks up through the trailing truck wheel immediately behind the traction tyre as only one wheel is insulated.   With both insulated it can stutter.   I used replacement see through spoke wheels, Jackson probably and I de insulated mine by putting very thin wire down the inside and back down the outside of the insulated bush and pressed the wheel on the axle before  trimming the ends. I also added a thrust washer super glued to the wheel so the wire didn't wear too quickly.

I replaced the wheels with ones of the correct diameter, so there is no longer any pick-up from the trailing pony truck. I thought of putting some kind of pick-up to the wheel on the right side, as originally designed, bought thought the better of it.

 

I do notice that with some of my old engines that haven't run in a long time, they do seem to get better after a light oiling and some running in. But not all. Not having a layout doesn't help.

[DCB]

The other problem with correct size wheels is the coupling ends up too high.  For no good reason I had about 6 of these, Father in Law had a couple which ran really badly and I bough a couple for spares and built slide bars from N gauge rail and by the time I finished I had  got about 4 or 5  going and sold on Ebay,   Several had fabricated front pony trucks and most had undersize but see through rear wheels, de insulated, but at least one had Airfix 14XX rear wheels, I broke the rear Pony truck in half filing the axle hole larger and braced it across the top with a bit of brass which in turn brought the coupling down level.    With the 14XX wheels I pressed off one tyre and the same wheel off its axle and set a couple of strands of fine wire between axle and wheel and then fed them between tyre and wheel as I pressed it back together to de insulate it.      I had so much grief  with some of the chassis , sorting the quartering, and axle flop, but they all ran fairly well when sold, some had brass bushes in the chassis to reduce axle flop, one at least had Triang axles with  Airfix wheels, one has a Hornby X04 motor, has as I am using it for an LNER J50 chassis,  Have fun.

[Dana Ashdown]

On 26/06/2022 at 09:11, Mikkel said:

I've always felt the large prairies looked a bit awkward but in this condition with this livery it's a very attractive loco.

My thoughts exactly. I think the higher cab roof removes that squat appearance of the Collett engines.

[Dana Ashdown]

On 29/06/2022 at 19:57, DCB said:

I broke the rear Pony truck in half filing the axle hole larger

I used a drill to ream the holes larger, so I did have that trouble.

 

The couplings are higher, but for the moment I don't see any major problems on that account. However, the short Airfix hook doesn't give much clearance for the uncoupling wire.