Atlantic's works: Portable layout - Ground Signals Again

[Atlantic 3279]

Moving the Brakes

The molded plastic Hornby brakes, acting on the rear of the wheels, are part of the chassis keeper plate assembly, originally looking like this from below:

I'd hoped for a "perfect world" arrangement in which it was possible to just unscrew the keeper plate, turn it around to put the brakes ahead of the wheels, and screw it back on. No chance! There an offset bulge in the plate to accommodate part of the final drive gear, and the screw holes are not the same at both ends of the plate. Okay I thought, I'll cut a new hole in the plate for the gear to pass through, and cover it with a plastikard box, then drill some new holes for screws. Off came the keeper plate revealing the next Hornby booby-trap. The rear set of shoes are not on the visible keeper plate, they are on a second layer, an "inner" keeper plate. Whilst the outer plate is flat-backed and can be turned around without too much troble, the inner plate is definitely "keyed" in place by a number of features that make it obvious that it strongly prefers to stay on the chassis the right way around. It is also the carrier plate for the power pick-ups, and is wired through to the motor with very little slack being readily demonstrable in the wire. The inner plate could be eased away from the base of the chassis block slightly, but short of engaging in a lot more dismantling, I wasn't going to be able to take it off, alter it, turn it around and re-fit it!
I'll show what I did in a little while......

[Atlantic 3279]

Outer plate off, revealing the inner plate with rear shoes still attached, and with pick-up strips sitting loose, very easily disturbed, and much more difficult to put back in place correctly!

The only practical way to proceed that I could see was to cut the rear shoes from the inner keeper plate, then reverse the outer plate and find a way to attach the extra shoes at the other end. Thinking that it would give me more "substance" with which to make a strong joint, I initially cut off the brakes plus the whole of each rear corner of the inner plate, i.e. everything behind the rear spring hanger. This was not a good idea. It didn't help with the later re-mounting of the brakes, and it left an undesireably large void in the side of the chasis aft of the rear coupled wheels. I later had to stick some of the material back in place. It is best to cut only at the line of my red arrow in the above image!

[Atlantic 3279]

Here's the outer keeper plate prepared for reversed fitting. I've removed the sandpipes from their original positions and refitted them into newly drilled new tiny holes in the supporting pieces behind the "other" set of brakes. On attempting to cut a new hole to accommodate the gear wheel (for which I stupidly tried to use side-cutters instead of a fine piercing saw) I snapped the plate in half, along a line just to one side of the existing gear-bulge. I therefore deliberately cut it at the other side of the bulge too, so that I had three pieces, and simply turned the middle piece around to put the gear-bulge where I wanted it to be, then bridged the breaks by gluing on a couple of layers of thin plastic. Finally I drilled the necessary new holes and screwed it back in place.

[mick b]

Good as usual.

What glue are you using for future reference as it appears to be the horrible hard ABS type of plastic.

[Atlantic 3279]

In order to fit the third (previously rear) set of brakes at the front, where I wanted them, the best I could think of was to drill the little blocks on the backs of the brake arms, drill the exposed front corners of the inner keeper plate too, and then use thin brass wire to pin (and glue) the brakes in place. I also drilled more holes and used a "staple" of brass wire to yoke the two brake arms together to give them more strength and rigidity.

Whilst a bit of tweaking with needle-nose pliers allowed me to pose this third set of brakes just as I wanted them, I then had the problem that the rigging wouldn't fit. Only then did I notice that the arms of the transplanted pair of brakes have a bend at the lower end, whilst all of the other four brake arms are straight. The fore and aft parts of the rigging are not therefore of quite equal lengths. I was able to partly sort this out by again using the fine pliers, this time to carefully bend the lower ends of the plastic arms themeselves until the rigging would fit. This looks right, but in practice it seems not to be ideal. I think the bent plastic brake arms tend at times to try to recover their original shapes, and this makes the loco run very lumpily as the brakes are then pulled on!

I may have to ditch the nicely detailed plastic break rigging and insted make up some to the right dimensions from 0.7mm brass wire. It won't be "exquisite" but it will be robust and will keep the brake arms firmly in place!


Hi Mick - nasty old super-glue. Could ABS be the acronym for "annoyingly bl**ody snaps"?

[Atlantic 3279]

An attempt at restyling the V2 motion bracket using a hand made 10 thou plastikard overlay, currently looking rather garish in white! I hope it may look "smaller" when black, when it will certainly be less obvious!

[Tim79]

That's looking rather fine there Graeme. Dare I ask what the "hours" figure stand at with the pair you're doing?

FYI, 524 is still somewhere in the 15-20 hours range, with just "blacking" and deflectors left to do....

Cheers,
Tim

ps: how do you go about doing the sanding rods above the fireman's side Cartazzi?

[Atlantic 3279]

The hours spent on the A2/3 are still more or less as we discussed separately a while ago Tim. I haven't bothered to time the A1/1 prototype - I'll do that when I have a full set of resin parts in my hand and address the second Sandwich, which already sits quivering in a box in the loft, hoping not to be noticed.

For the sand control rod (if that's definitely what you mean) on the firebox side it was simply another case of marking the position at which it would pierce running plate and cab front, and then slowly/lightly twiddling drills by hand - making sure with the running plate that I had a good centre indentation first and that I kept the drill at the correct final angle to minimise risk of snapping it. A bit of lubricant didn't hurt either.

That reminds me though: I haven't done the fairly obvious main levers below the running plate that operate the drop-grate (which Bachmann don't see fit to give you on A1 or A2) nor the smaller mechanism on the other side that is either to do with grate or ashpan - I'm not sure which. For the main ones I usually just solder two strips of brass or n/s together at an acute angle. Hornby-based super-detailed replacement Cartazzi frames for Bachmann locos, as currently shown elsewhere on here at present, are putting my efforts in the shade......

[Blink Bonny]

Graeme, I fail to see how anything could put your efforts in the shade.

Good on yer!

[Atlantic 3279]

Very kind of you to say so, tha' knows lad.

On the matter of "shade", you can't get a darker shade than black (okay, I know this is a corny link), so here's that motion bracket in black. Looking better?

Cross bred Hornby-Comet valve-gear in close up:

I've been thinking about that patchwork smokebox too. I think it would now be better, and just as easy for me, to make a whole new master smokebox as a piece of plain plastic tube, add resin duplicates of the superheater covers, and then cast complete new plug-in resin smokeboxes for future A1/1 conversions. I don't want the existing plumbing and anti-carboniser valve details, the top s/h cover should be more or less square not rectangular, and a full new box would save work on blending joints. The only cut and joint would then be against the first boiler band, so should not need any blending, just neat cutting and joining. I'll have to take impressions of the s/h covers rather than transfer the originals to my new smokebox, as it is not possible to cut in a way that saves the covers without destroying the adjacent lined boiler band. I want an impression/mould of the lovely Hornby chimney anyway, so I may as well do the header covers too.

[S.A.C. Martin]

Personally speaking, it works for me. I think when painted black, it looks the part most definitely.

I'm intrigued by the prospect of a resin smokebox. Definitely easier than adding onto an existing one.

[2002EarlMarischal]

Sounds a great solution for those following in your footsteps as it were. Looking at my model of Sandwich, sitting in blissful ignorance of why it was bought, I think this means that the cut would have to be through the back riveted edge of the superheater covers, which is probably just the width of a fine blade?

[Atlantic 3279]

Yes, I reckon that rivetted flange is so narrow and so tight up against the boiler band that you must either wreck the flange or wreck the band. I really doubt that you could cut "between" the two leaving both unscathed.

[2002EarlMarischal]

Please forgive a basic question, but how do you achieve such tidy, straight cuts with awkward shapes such as loco bodies? Obviously they are crucial to the success of these conversions. If you have photographed the technique in one of your earlier builds and can recall which one it was, I will happily hunt back to find it. Many thanks!

[S.A.C. Martin]

Yes, I reckon that rivetted flange is so narrow and so tight up against the boiler band that you must either wreck the flange or wreck the band. I really doubt that you could cut "between" the two leaving both unscathed.

That being the case, why not mould it to include the boiler band - making the cut on the boiler side of the boiler band?