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The future of loco kit building


Guest oldlugger

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On the subject of discounts (although I agree we're off the thread a bit here), if someone comes along and asks to buy, say, 100 coach dynamos in bulk then I haven't had to sit and count out those castings into individual packets, so saving my time and packing costs - which can be reflected in a discount. On the other hand, if someone were to want to buy 100 coach kits I would still have to spend all the time picking the individual components and then have the associated packaging costs, so what saving could I pass on in a discount? And if I haven't made a saving, why should I receive less income?

 

Geoff

Comet Models

 

It all depends on whether stock sitting on a shelf costs money against a potential sale of 2 kits. Whilst profit is important a certain amount of turnover is equally important as inventory costs. 2 sales at a lower price providing there is still a margin may be better than no sale. Each individual business needs to work out what is best for them. Often if I am buying in bulk I'm happy for it to be all put in one box usually with only one set of instructions. If a deal can be done on that basis then it could be win win. Cash coming in can be reinvested in more stock which may or may not be replacement of items sold.

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Lovely loco Derek! It is a bit hard to tell from the photo exactly which bit pivots where but that looks very like the same sort of arrangement. Next time I venture to the shed, possibly this evening or maybe tomorrow, I will get the camera under the Denny loco and post something on the grounds that a picture is worth a thousand etc.

 

Tony

 

Here are a couple of photos of the undrneath of the "Denny" 0-4-4T. I have posed the driving wheel section of the frames at each end of its travel. It is not great amount of movement but it is enough to make it a superb performer around tight curves. The rear bogie pivot is fixed, in that the bogie can turn but does not move from side to side. This cuts the rear side to side swing of the buffers to a minimum.post-1457-0-46884700-1354092641.jpgpost-1457-0-69642400-1354092646.jpg

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Nearly every kit I have built has frames so narrow that they need washers anyway. I have built several and used P4 frame spacers supplied for an EM loco and still had to use washers. The problem with increasing side play allowing wheels to catch on splashers still applies though.

 

In my stockpile of kits is one for a M&L Premier Kits GWR County Tank its instructions say if building in OO it may be necessary to file off the back of the wheels to allow the wheels to fit the frames. Don't know how good this kit is otherwise.

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In my stockpile of kits is one for a M&L Premier Kits GWR County Tank its instructions say if building in OO it may be necessary to file off the back of the wheels to allow the wheels to fit the frames. Don't know how good this kit is otherwise.

 

That is a pretty scary thought! How far do you have to file, until there is no flange left?

 

It sounds like one of those cases where a manufacturer has discovers a fault, not bothered to correct it and tries to cover their back with a note like that in the instructions. M & L kits were first produced a long time ago and date back to the days when a lot of OO gauge ran on real "steam roller" wheels. I would have thought that a more modern wheel, like a Gibson, with no big boss on the back would not need filing! I would have thought it a better bet to modify/make/find/scrounge the spacers (assuming it isn't a solid block).

 

It would be interesting to measure a spacer, add two frame thicknesses and see what measurement you get.

 

It is the first time I have ever heard of that problem in a kit! I haven't built a County tank but somebody on here must have done. I have done some M & L LNWR stuff and they were not bad for the day but you had to be a bit clever getting EM wheels into splashers on them.

 

Good luck,

 

Tony

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On the Saturday at a recent show, I gave one of these to a fellow exhibitor. In the morning he said he had a complaint, and that was that it had only taken him half an hour to solder up the frames and if he had had the wheels he could have had rolling chassis that night. Springing these frames is as complicated as clipping two wires into place.

 

Exactly as it should be the problem is that such kits remain on the exclusive side (and by that I probably mean "unknown to but a few"). and of very little use unless that is the prototype of interest. Would it not be better to be an (one of) adopted standard for alll kits. Perhaps we would nolonger then be debating the merits/demerits of fixed/compensated/sprung?

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The thread is about the future of kit building, I think Bill's post lies in that direction.

You could probably argue that a Brassmaster's easi-chas isn't a kit in the full sense of the word, but it involves a lot of the techniques you'd use to build a kit. The replacement chassis for the Bachmann 3F tender is sprung, and it couldn't be easier to build. There's nothing even to solder, it's all just fold and assemble. As with Bill's chassis, the spring mounting points are just fold out tabs. The wheel bearings are fold-ups and the spring just slides through the top of the fold. It really couldn't get much simpler.

The resulting chassis seems to ride very smoothly, reading the instructions probably took longer than actually making it. Damned instructions!

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...Would it not be better to be an (one of) adopted standard for alll kits. Perhaps we would nolonger then be debating the merits/demerits of fixed/compensated/sprung?...

 

I'm really looking forward to building one of Bill's loco kits* but it would be a dull world if all kit designers adopted the same style and methods. That would make kit building more like a production line and I'm sure it would reduce the enjoyment for most of us, even those who build professionally. For me, the process is as important as the final result.

 

As to the "fixed/compensated/sprung" debate, I don't think anything will stop that :scratchhead:

 

Nick

 

* when he gets around to releasing the S&DJR Scottie. According to the web page, he needs a couple more subscriptions, so come on chaps, you know you want one...

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For those who may be sceptical about just how simple a set of frames can be made, I've put some renderings on my blog.

 

I have never yet had cause to design a kit for a set of loco frames (a situation which may change quite soon). But it seems to me fairly obvious that by following the basic properties of geometry, it should be quite easy to design something which can only be assembled if it is properly square and can't be assembled any other way.

 

Perhaps I have missed something?

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I've often wondered why MORE use is not made of plastic in kits. Plastic brakegear looks like a winner. Plus I suspect if the right sort of plastic was used, it could be sprung into place, making wheelset removal easier?

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I've often wondered why MORE use is not made of plastic in kits. Plastic brakegear looks like a winner.

 

It has a tendency to melt as soon as a soldering iron is brought anywhere near it. Think white metal and all your worst fears.

 

Seriously though, Bill, I like the idea - a cast brass chassis with matching hornblocks, so designed in, and brake gear that isn't the root cause of all shorting issues with a sprung chassis, so it can be designed to run close to the wheels where it should be. .... but will it be available in OO ?? ;) Why didn't someone think of that before?

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My point was that MOK seem to be going down the plastic brakegear route, why not others?

It would give a better representation than etched brakeshoes aqnd no shorting.

 

And even I would know better than to try and solder it....

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I've often wondered why MORE use is not made of plastic in kits. Plastic brakegear looks like a winner. Plus I suspect if the right sort of plastic was used, it could be sprung into place, making wheelset removal easier?

 

I general the tools for plastic moulding are far too expensive for the numbers of kits that are likely to be produced to use them. If you look at the companies that have produced injection moulded plastic loco kits in the past there basically aren't many and those that did were plastics companies that did some railway stuff rather than the other way around.

 

Having said that Alan Gibson does a range plastic brake hangers and shoes in 4mm but not in 7mm.

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I general the tools for plastic moulding are far too expensive for the numbers of kits that are likely to be produced to use them. If you look at the companies that have produced injection moulded plastic loco kits in the past there basically aren't many and those that did were plastics companies that did some railway stuff rather than the other way around.

 

As much as it pains me to even contemplate saying this, my general dislike of multi-media kits being well known, - but isn't this a case for 3D printed parts?

 

Also I see the frames themselves are brass castings, is there some mileage in considering splitting the casting down the middle line to produce split chassis power collection/isolation or iis this too much of a retrograde step back to those designs of the 70's?

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I have thought of split frame pick up, but I think before that will happen there needs to be a range of wheels on the market that has been specifically designed that way. It is really not a good idea to have the modeller spend hours fettling wheel set to drop into such simple frames.

 

As for OO, most of the frames I have done so far have been for RTR bodies and I really don't see the need for these in OO. However I will be doing a range for full loco kits and obviously these will be available in OO as well and the other gauges.

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Perhaps a start would be for someone to market an axle compatible with Slater's wheels, but electrically isolated?

 

Separating the frames and making each wheel live to the tread is easy compared to making the axles insulating.

 

One wonders if Slaters could be persuaded to give it a try?

 

It would HAVE to be simpler than the present method with drill, piercing saw and Araldite, mind......

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Perhaps a start would be for someone to market an axle compatible with Slater's wheels, but electrically isolated?

 

Separating the frames and making each wheel live to the tread is easy compared to making the axles insulating.

 

One wonders if Slaters could be persuaded to give it a try?

 

It would HAVE to be simpler than the present method with drill, piercing saw and Araldite, mind......

 

Exactoscale wheels come with a split axle. All that is required is to connect the tyre to the boss. A couple of us are looking at the possibility of electro plating the wheels.

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Branchlines do, or at least did in 2005 when my catalogue was printed, split axles, both 2mm and 1/8" diameter. There was a small selection of wheels available as well, two Manning Wardle types, Terrier, and industrial Garrett.

 

Not sure if they are still available, I can't make head nor tail of their webpage/bloggy thing.

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Branchlines do, or at least did in 2005 when my catalogue was printed, split axles, both 2mm and 1/8" diameter. There was a small selection of wheels available as well, two Manning Wardle types, Terrier, and industrial Garrett.

 

Not sure if they are still available, I can't make head nor tail of their webpage/bloggy thing.

I thought it was just me. Fortunately I do not do much 4mm these days.

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For those who may be sceptical about just how simple a set of frames can be made, I've put some renderings on
.

 

This would be very effective indeed , and would get round the terror of "can I solder 100% square because 98.5% square isn't good enough for it to work properly..." . While someone will no doubt come up with the idea of generating this kind of thing as a 3D print, I would imagine that, at current standards of print quality, the result simply wouldn't be good enough to achieve the fine engineering tolerances required (and it would probably wear very quickly, unlike metal) Whether 3D printing might offer an effective alternative route to producing the brake gear/keeper described as sintered nylon, I don't know

 

Would the brass casting require machining (by the manufacturer) or does the design, with seperate floating bearings mean that the casting is adequete as it comes out of the mould? (I have no workshop / engineering background so no idea what the practicalities are here)

 

I would hope that people would be willing to pay an extra £15-£20 on the kit price for a product like this with easy assembly of a frame certain to be square. The difference between a failed kit build and a successful one, plus the time saving, has to have a significant value

 

I admit an ex Midland 0-6-0T was in the back of my mind as a possible subject for a bodyline kit, with a view to using a Bachmann 3F or Jinty chassis. Presumably that would require an alternative footplate to be provided in the etch, though whether that would be a commercially sensible route to take, when the kit could be a showcase for the new frame system, and therefore might perfectly well be available with OO frames as an alternative, I don't know

 

I presume there are no difficulties in building such a chassis for DCC - insulated wheels all round ? The pickup strips , if attached to the keeper moulding would presumably be electrically isolated from the frame?
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Let's hope that the shrinkage factor in the metal casting for the chassis is properly allowed for and consistant over various batches otherwise we will be back to the problems of making the rodsfit!!!!!!!!!!

 

ArthurK

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Exactoscale wheels come with a split axle. All that is required is to connect the tyre to the boss. A couple of us are looking at the possibility of electro plating the wheels.

 

Wrong scale: I want/need 7mm

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