heraldcoupe

I've had a few of my Bulldog and Duke bodies listed on ebay, with quite a few more selling through various forums by word of mouth. I have the three major frame types of Bulldogs and wide/narrow Duke cab variants. Beyond this, I've built a library of 3D components which make a lot of individual loco configurations possible, but not all have been committed to print. As mentioned elsewhere, I have a few other projects in the works. I am working towards an ecommerce website, but a demanding day job keeps getting in the way. I pick up messages here and will quite happily sell this way whilst getting my act together on the website front, Cheers Bill.

It's good in theory, but many (most?) people offered a choice don't relish the complication. I've patterned and printed all 10 of the Dukes which survived past nationalisation, most customers have just asked me for wide or narrow cab variations, the rest is just unwanted noise. SImilarly the Bulldogs, beyond straight/curved/deep frames, not that many people are concerned. Cheers Bill

There seems to have been variation from what I can determine in photos, though finding any images taken from a helpful angle is a challenge.

This one was something of a one-off, a two-off I suppose as this was the first attempt which had the aforementioned defects. Most of my subjects are later examples, but this one was based on this 1920s image of 3330 Orion and has many earlier features: http://www.gwr.org.uk/440-pics/3330-orion.jpg

Scaling down is sadly a lot more difficult than scaling up. A lot of the details in 4mm sit at the limit of what can be reproduced. Increasing size means features can sometimes be further refined, but they're there and will stay there. In 2mm scale, things have to be beefed up before they'll print at all. I did some trials of an unmodified Duke in 2mm scale and while the overall shape was recognisable, all the fine detail turned to mush, or was too fine to support itself. It can be done, but it's essentially starting again, with a lot more compromises to be made.

The kink in the footplate is already there, as is the step which I'm afraid you don't need...

Personal contact at the moment, but I am trying to get more organised in terms of a website. As well as my full-time job, I run a (very) small part-time business making classic car parts, however making locomotive bodyshells has become a much more in-demand activity. I've only ever formally listed my development reject shells on ebay, but I am about to put list of the finished products as it's a more straightforward sales route than expecting people to find me online. As something that's growing organically, there's been little planning...

That matches my observations so far, but always aware that absence of proof isn't proof of absence...

😁 I am very interested in producing saddle tanks and have some rough patterns done. The Bachmann chassis will be a good starting point for those sharing the same wheelbase and wheel size. I'm hoping many of the major structures will carry across to a Buffalo (and others?) in due course, but I've not done a deep dive on that yet. The latter will have it's own mechanism, the design features of that being proven on my Aberdare project.

If you find an image of one with topfeed but lacks the boxes, I'd be very interested to see it. I've built a library of parts which takes me some way to printing other early examples, but I don't have enough reference material to be certain on exact spec for given subjects.

The boxes cover the firebox mounting brackets. I don't know their purpose, but they were introduced quite early and I've always associated them with the introduction of topfeed. I'm not convinced they're absent on 3301, the perspective of the photo would put them largely behind the splasher and nameplate. There appear to have been some which were shorter than those I've modelled. The tiebars are included in Bachmann's accessory pack for the Earl. The shell is designed for them to fit.

Equally relevant I guess, I have done 4mm shells with open frames and boiler underfill for those looking at a finescale chassis.

I have a 7mm print of a straight frame Bulldog on the shelf at the moment, I've previously done some of my Dukes in the same scale. No reason why I can't configure the curved frames for a 7mm print. When enlarging them, I've filled in the boiler underside and opened out between the frames as these are dictated by the Bachmann mechanism on the regular product.

Good advice. As the designer/producer of this Bulldog bodyshell, there's been an awful ot of thought and testing on suitable materials. They're currently being printed in Siraya Tech's 'Build' resin, which was chosen for a number of reasons, not least because it is drillable. Not that care shouldn't be taken, but that it should behave better than some other resin prints.

Which by coincidence, is one of two (the other is 3313) curved frame shells I've produced, in it's latest condition... As far as possible, my shells are based on specific subjects where I have photographs at a known point in time.

Possibly giving away my secrets here, but I drew a line when the print quality reached a certain resolution. There are better printters on the market than those I am using, at least in terms of finesse, and for little money. That increase in resolution brings with it increased maintenance, and limitations on which resins can be used. Many resins have proven quite unsuitable in terms of long term stability, so if I can't use a material I already know is fit for purpose, testing has to start all over again.

The cab photo reminds me. That reversing wheel/lever is very fragile, and right in the line of fire when the bodies are taken of the supports structure. Consequently, they often lose one or both handles, so you'll find a spare piece in your bag of bits with the shell, Cheers Bill.

Indeed not, it would also remove the need for captive nuts as holes could be tapped instead, further simplifying.

The precision is in-built to the design, no folding/soldering/alignment, just screws and nuts to hold it together. I've acquired so many poorly assembled etched chassis' as abandoned projects through the years, it's left me wondering what the ratio of completed to abandoned kits might be. I've designed the prototype to run with Hornby 08 wheels as they come with pre-installed bearings where the Bachmann set runs direct in the block. But that's just to get a running mule, Alan Gibson does the right wheels and I will be getting a few sets in to test once the basic design is proven. Cheers Bill.

I could make a case that a large number of Bachmann chassis' will suddenly become 'surplus'...

These are two real needs I recognise.

I think we need to look beyond traditional chassis designs to really exploit new technologies. In designing my shells, I was keen to produce something which got away from reliance on soldering and precision assembly. With many RTR models having some degree of springing, a rigid chassis would be a step backwards from where we are. I also don't think such compromises are necessary. While I see limitations with the currently available materials for MSLA printing ( the area I work in), new materials are appearing all the time, though often at eyewatering costs. The other popular means of 3D printing, FDM, gives a less refined finish, but the range of materials is impressive. For a functional chassis, it may well prove a viable method. In the meantime, here are the bare bones of the Aberdare chassis prototype in CAD form. This has compensation across the six-coupled drivers, with the pony to be lighly sprung. It will print up for development purposes on my existing machines, once the design is proven I'll start looking at FDM processes, which is a new area to me. The compensation beam is deliberately chunky, with a steel shaft through it to provide the pivot points for the axles. The wheelset and gears aren't fuly drawn as I've no intention of printing those...

I'm looking at an earlier 0-6-0 tank in the near future. Focus is on a saddle tank, but core design work will be the same for a Pannier (or side tank). There's an obvious incentive to create something which fits on a RTR chassis such as Bachmann's 57xx (or 64xx I supppose) but I keep getting drawn to the 1076. If the Aberdare's chassis works out then I'll have a functional design which can be modded to other wheelbases.

I was toying with the idea of a Saint, but there's no easy RTR chassis to be used, and even correct wheels from the specialists don't seem readily available

🙂 I'm always open to suggestions...