bogieman

Neat! I'm not that talented an engineer though. I presume you have to make a set for each diameter of driver? My first attempt at Jinty conversion with fixed chassis and no "slop" runs down to 15secs for 10 inches which I make about 6 scale mph. How much will a "sloppy" one run down to? Walking pace or less I guess and then I'll be depressed because I don't really want to unsolder the crankpins and brakegear now! Maybe I'll just leave it in a siding or sell it and start again. And I like Richards's polishing idea particularly as you have to do something similar to remove the paint from the tyres if you spray paint the drivers.

Thanks for that I'll see if I can find the sheet on the YAG I must have missed it. Will also look up article. The problem I foresee is quartering. Dead easy when there's no slop in axles as the etched rods are so accurate. But add in the axle slop and you're into a completely different game with possibility of jerking wheels as coupling rods "rotate" if quartering not spot on and you've lost one of the ways of it happening naturally. Just a thought.

Could I ask ("enlarged axle holes as recommended".) how large? ("I wasn't satisfied with its performance.") was that speed, pulling power, ultra slow speed or reliability at not stopping due to loss of electrical contact? ("enlarged axle holes") was that all axles, front and rear or just centre? Thanks

The figures I used are from a gear mesh calculator on the internet, don't remember now from where, but I copied all the figures out and kept them as a Excel file for all the 100DP gears readily available in small sizes (shop ones are in bold) i.e. 14 15 18 20 21 24 28 30 31 34 37 39 42 44 45 52 I did check them against various books and other internet sources as well as working them out as best I could mathematically to check them. However I'm no mathmetician or engineer so I could have slipped up on one or two. The figures for the 64DP amd M0.4 and 100DP shop available ones certainly match the figures given in the Year Book tables. And you're right I haven't just stuck with the 2mm SA shop tooth sizes as I have a small stock of other tooth sizes also from places like Branchlines or Ultrascale so that I can play about with gear spacings and ratios. Certainly when I work with the figures in my composite chart things seem to run ok which for a non engineer is to me the ultimate test.

Well Chris I'm no engineer so you can perfectly well say I'm mad or stupid and I won't mind but according to the gear meshing tables the centres for gears are quoted as follows: 64DP 14T to 18T = 6.35mm M0.4 14T to 18T = 6.40mm 100DP 18T to 31T = 6.35mm 100DP 20T to 30T = 6.35mm I tried the 3rd and 4th options and they both work perfectly well with apparantly good meshing but decided on 18/31 and it has survived testing under load for three days continuous running on a shuttle circuit. My rationale is that 100DP gives you a greater number of ratio options and ability to have a bigger ratio thus enabling the loco to run more slowly and with better control for shunting. Which is what I prefer. Tony

Thanks for that Chris yes I had noticed the extra holes (talking of extra holes what are the holes for in the etching of the springs in the 57xx?) Do they need to be on all three axles? I've used all100DP gears and not 64DP but assume they could still be used I was reluctant to open up the holes to 1.6mm when it ran perfectly well at 1.5mm Yes it runs fine on wires connected direct to motor at very slow speeds and with hardly a flicker from a milliammeter needle as drivers slowly rotate. After running it in some more on a little shuttle unit the pickup problem now comes down to just the front pair of drivers which is strange given that the centre drivers are up a hairsbreadth. I found your coupling rods so accurate that when the second side slides onto crankpins easily I know the quartering is correct. That why I preferred no slop in the axle bearings or the crankpins holes. And I'm reluctant to take it apart now that all the brake gear etc is on and everything painted. And fortunately it is getting better with running in on the shuttle rather than on rollers or against the buffers.

Axles in generous axle holes - how generous? It may indeed be that the chassis is not dead flat. In fact on an 0-6-0 it's better to have the middle axle a touch high. - The chassis is dead flat on testing with mirrow and the centre axle by luck is marginally up by a hairs breadth. This axle should then have two light phosphor bronze springs on it.- Do you mean on the centre slightly raised axle? This adjustment must not be done on the driven wheel, of course. - sadly the centre axle is the driven axle! And in answer to Jerry's questions, are you testing it with the body on? - yes on and off makes no difference and I've tried loading it with a large piece of lead sheet wrapped over the loco. have you used any additional means of pickup eg. Simpson springs? - I've looked up Simpson Springs but cannot find a picture showing exactly what is meant by this. do all the wheels sit squarley on the track - yes the front and rear ones do but the centre ones are ever so slightly raised adding very fine conventional wiper pickups - both back and top acting.- Please can you point me to a diagram or picture so I know what you mean exactly. (sorry to be dense!)

I've just built my first etched chassis (for the Jinty) and it runs ok and reasonably slowly too provided it's on electrical leads direct to motor (Faulhaber 10/16). Problem is it's not very happy on the track and keeps stopping if I run it too slowly. When this happens turning up the power does nothing as it requires a slight nudge to restore electrical contact at wheels/track. I've tried: Running it in on rollers Running it in against the buffer stop Cleaning the tyres Cleaning the track Adding weight Different controllers such as Pentroller, Gaugemaster, old fashioned transformer/rectifier/variable resistance But nothing seems to help. Any suggestions other than the bin and start again!

That sounds interesting idea Chris. But where do you buy drills in 0.01mm increments? And when I do find some what do you recommend going up to - 1.54 or more or not so far? Tony

On the subject of etched kits/chassis can someone advise me as a beginner on using the 2mmSA black axle muffs. They seem so tight as to be almost impossible to press the driver's stub axle into them without giving one cause to fear bending or damaging the delicate etched chassis or ending up with a bent and wobbly wheel. So my question is should the hole be eased in some way and if so how without making them intolerably loose. I've tried using a 1.5mm hand reamer but it removes no material from the hole and certainly does nothing to ease fitting them.

I'm building a couple of 57xx Panniers and the Jinty all at once using these Chris Higgs etched chassis. I'm writing it up as I go hopefully to get it published in 2mm magazine as I'm using the more radical approach to the bodies. Because they have same size drivers, are all 0-6-0Ts and use the same gear ratio I'm hoping to compare the results of using three different motors. My problem is that at this late stage I have just realised the Panniers have identical cabs styles, when I had planned to make one of each version (earlier 1929 Churchward 57xx style cab and later 1933 Collett 8750 style cab). Mine are both the later Collett 8750 cab types with rectangular spectacles, in fact a spare I have is also of this type!! Does anyone have a Grafar body of the earlier cab version with circular spectacles they would be prepared to swop or sell? Even just the cab alone as it's a separate plastic moulding that slides upwards and off. Many thanks

I feel the same about motors/worm mounting (and indeed about the whole chassis assembly with brake gear etc) but in discussion recently somebody asked, how many times have you taken a chassis apart for repair once built and nobody could give a single example. Is it possible we are being too cautious?

Thanks for the blog url Andy most useful. Thanks for the answers offer Richard, sounds like machining the body is going to be a pain! Tony

Thanks Andy, got it in front of me but not read it yet but will shortly. "Double Heading, a trial run" pp44-47.

That's useful to know although my searching hasn't found it yet. Hi Richard! Any ideas? Maybe if it's no longer available on the internet you've still the photos on your computer? You already know my email address. I'm currently thinking of building both chassis types from the one etch to try things (different motor fittings and amounts and sites of metal removal etc.) although I realise I'll only have enough parts to completely finish one that gets chosen to use. Then I could write up an article with the answers to my original query. Thanks Tony

That all sounds pretty difficult but I might still try the rear axle drive just to try to get the improved appearance. There's some nice photos of the chassis and motor on centre axle in the instructions and earlier in this post, does anyone have (a) similar photo(s) of the rear axle build?

That's very interesting as I hadn't realised the metal removal was to fit the motor. I had been under the mistaken impression that it was a cosmetic exercise to give a clear view under the boiler. What therefore is the biggest motor one can fit after say minimal removal of metal? And does it mean that even with the drive on the centre axle for this conversion you had to remove metal to fit the motor? I'd appreciate knowing what size motor you managed to use or that one can get in? It would be useful to have comments from others who has done it one of either ways and the difficulties involved in removal metal to get a motor in.. Many thank for advice.

With the 57xx etch chassis conversion now available can anyone summarise the pros and cons, advantages and disadvantages or just the difficulties of using the rear axle drive compared to the centre axle please. I'm just about to start and would appreciate guidance on which to use. Many thanks

Please does anyone have a Chris Higgs 57xx Grafar chassis etch they're not planning on using for a while, could thus wait until they are in stock in the shop again and would be prepared to sell to me? I've finally managed to locate a 57xx body at a reasonable price but now find the etch is out of stock! I have wheels, gears, motors the whole set up but thought stupidly that the etch would be easily available when everything was ready to go. I wanted to use it's building to write an article on some ideas I had for building one, although my ideas might not work out of course. Many thanks

About how long? Weeks, months or years?

I'd join you in this with order for two etches al least but only if 2mm not 2.06mm!! Sorry about that Richard. The relative standardisation of GWR tenders is very useful for modellers I always think.

Chris Any current information on possible date for availability of these (48xx and 57xx) etches?

Has anyone tried "The Greenwich Coupling CPL1 00/H0 NG coupling" for narrow gauge railways ? As an alternative and at the risk of starting a spate over the various options, what is the "best" 2mm scale coupling (i.e. neat, unobtrusive, reliable, easy to fit and adjust) coupling for a beginner?

Thanks for your help. I have 3-106 that have a head 0.5mm high so they stick out of the back of the wheel quite a bit. Sounds like I have bought the wrong crankpins! Maybe I should get some 3-107, I guess the flange goes at the front on these too saving having a washer. Are they soldered from behind also?

Could I ask a new question as I'm building my first 2mm scale loco and I've met a snag. It's about the 2mm SA loco drivers and crankpins. How does one fit the turned brass crankpins into the drivers? The head of the crankpin sticks out from back of driver so do I countersink the hole, or file the head down? And if the latter do I do it before or after fixing in the wheel? Also how do I fix the crankpin in the driver? With glue or solder? Many thanks for any advice,