hollywoodfoundry

Unfortunately, like many others, they do not state the maximum resolution obtained using their process.

No, I have not tried any of the Korean suppliers, but I don't need to. I can get excellent builds from Fineline and I have an excellent local brass caster here in Australia. But I have had other dealings with Korean suppliers for other projects, and they were generally not satisfactory. The communication is a difficult issue and getting what you want, at the quality you want, is like having teeth extracted. I certainly would not pass a build straight from the 3D builder on to the casting company, you need to see what comes out first.

When you are casting lost wax brass parts, any material will burn out quite easily, it does not need to be wax. You would be well advised to get something small done with any company you locate, before you commit to a complex build, as what they advertise and what they end up producing are quite different. I have tested quite a number of providers from all around the world over the last 5 or 6 years, and that's why I settled on Fineline in the USA. And cost is not a good indicator because you usually are making a pattern from which to cast more items, and you need to have the best pattern you can get.

Just guessing mind you, but as there are VERY few people doing Melbourne suburban trains of any sort, getting one in OO is going to be near impossible. By and large, Australians model in HO, not OO.

I could not find anything on those sites that tells me the resolution they offer. I am not saying it is not there, but without it, it is meaningless. Re the Solidscape printers, no, because ALL my masters are for either brass or pewter casting and so far the Viper seems to produce the best results. I don't do resin casting from the masters.

Yes, that part is made on a Viper. Interesting that they aim towards the 'hobby' market, because the 'discerning modeller' would want better resolution than Print-A-Part can do. I have been dealing with Fineline in the US for about 4 years now, and during that time it has taken me some effort to convince them that anyone wanting to use the service for making good quality printed parts would want higher resolution than they have been offering up until now. Although the new high resolution process is a bit expensive at the moment, it is still cost-effective for making masters to cast items from.

If the OP lives in Melbourne, then most likely it will be HO scale. Black Diamond models is still around and quite well: http://www.blackdiamondmodels.com.au/ There is also another group making kits available for the Comeng and Hitachi suburban trains. I can provide you with an email address for them if you PM me.

Simon, I imagine the price may be less for a thinner part, as the cost is directly related to the build time. But my part is only 2mm thick, and in most case you would want the panel to be not much thinner than that anyway. And yes, I think that grille in 1/32 would be easily achievable. Geoff

I have gone back to my older camera to try and take better photographs of the 3D build, and I think these 3 show the part in a better light. The first photo shows the smooth surface produced, but you can see a small amount of stepping in the louvres on the door. However that stepping is not really visible to the naked eye. Note how fine the door latches and hinges are, the hinges are only 0.7 x 0.8mm in size, and 0.1mm high. That's 4 thou in the old money, and the peak resolution of this process is 1 thou. The third photo shows the sand filler cap. This part is only 2mm in diameter and you can even see the heads of the two bolts that hold the cap lever in place. These are 0.2mm in diameter !!

No, but I don't think the idea is to own one of these machines, at least not for the moment, they are far too expensive. The best thing is to use bureau services to have them made. I will eventually have to have 13 sections made like the one in the photo for a model I am going to manufacture. As for milling mechines producing better results, not in my experience. I have a Sherline CNC mill that is capable of producing really top class work, but it does not come even close to the resolution of the item in my recent photograph. It is a pity that the photo does not do the item justice, because if you could see it in the flesh, so to speak, you would be amazed at the resolution.

Hmm, Reprap is fine if you want to produce parts that have the resolution of Lego. But not for anyone who is serious about the quality of their parts.

This part is to be a test, so it will not end up being painted. The next process is to lost wax cast the part in a form of special bronze metal. This will destroy the original part in the photograph. Then, the bronze master will be used to make a spin-cast mould so the part can be produced in pewter. The whole idea of the test is to evaluate these 3 processes and determine what the shrinkage factor is. The sandbox filler cap is exquisite in its detail, but probably will be removed from the production version as it will not cast very well. I might say also that I examined this part under a 20X microscope last night, and it still stands up well. I will try to photograph it better, when I can get the hang of this @!$!#@ DSLR camera.

Well, you would need to spend a lot of money to use it for just one model. The idea is to use the 3D build as a casting master to produce bodies or parts for sale. It would be terribly expensive at the present rate to build your own models that way.

Fineline Prototyping in the US have now introduced what they call 'Micro Resolution' builds in a new material. I sent one of my drawings to them to have a test build done so I could evaluate the quality of the process. The item is the side of a diesel locomotive hood section. It is only 40mm by 17mm in size and 2mm thick and the height of the raised louves is a mere 0.18mm. The hinges are only 0.1mm high, the door knobs are 0.5mm in diameter and 0.42mm high, with a domed top. I think you would agree the resolution is stunning, despite my poor photography. The cost however, is high at present. This one cost me the equivalent of £112.00 including shipping charge. Finally, the process is now at a resolution that is hard to fault. And there is no surface texture to the part, everything has a clean glossy finish to it.

Luc, If you want this to power a Bo Bo locomotive, that suggests you want the locomotive to pull around some stock as well. Keep in mind that this mechanism drives two axles only out of 4 available. That's a pretty poor design for a locomotive, barely OK for underground stock. Geoff

If visiting, you would be best to contact a local modeller and ask them to show you around the shops, as they are hard to find and often not located in city centres due to the high rents. There are nowhere near the number of model railway shops in Australia that there are in the UK, and probably nowhere near the number of railway modellers either. Keep in mind that Australia is a vast place, you could stuff the entire UK in there around 60 times, and with a population of only 21 million. As a result, many Australian modellers purchase via the Internet, and some sellers of RTR models only deal via the Internet. Model railway shops have been dying off in Australia steadily for some years now. Because of the geographic distances, modellers often find it more convenient to buy by mail order, and doing so via the Internet is becoming more the norm. There is one main model railway magazine, the Australian Model Railway Magazine, published primarily by volunteer labour by the Southern Cross Model Railway Association, a NSW club. It is mostly distributed by mail, but is sold to a few news agents and bookshops, but is not easy to find. It does IMHO, an excellent job, and features almost exclusively Australian prototype.

Something that is 'beyond repair' today may very well be feasible to repair in 10 or 15 years time. The idea of scrapping anything if it can be put away and kept is against the concept of railway preservation. Even parts may be useful, if another preservation railway needs to repair a locomotive of the same type, the hulk can be cannabalised for spares. Perhaps throw a tarp over it and get someone to paint a scenic landscape on the tarp so it blends into the back ground.

You just jogged my memory with that, the blue part shown was a previous build that I was not happy with. I asked them to do it again with a different material and orientation. The red material actually produced the brass casting you see. I have not done a large curved section like a roof, but I know someone who has: http://www.trainsdantan.com/ Cyril Ducrocq makes all his models using 3D printing, on an Eden printer, and the results are very good. Click on the main menu heading 'Les Kits' to see how he does it.

Oh, and this is the drawing they were created from:

The following photos, unfortunately, do not do the product justice. They are side frames for a Brill 4 wheel tram, the bottom blue item is one of the builds I received and the brass items are the side frames lost wax cast from the build masters. I got 7 identical masters of this build for about 40 pounds. The material used was Somos Prototherm 12120 resin. I have had a number of other items built from Fineline, but I don't have any photos of them. Sorry about my poor photography.

That may be possible for low-pressure injection moulding, but the material is unlikely to stand up to the rigours of normal high-pressure moulding, the die would be destroyed. In fact, for anyone considering producing an injection mould die, you usually have the tool nitrided to increase its hardness, and therefore its lifetime. Low-pressure injection mould tools have very short lifetimes and IMO are bad value-for-money as you end up paying for them much more often. If you want better surface texture and higher resolution for your SLA prints, may I recommend Fineline Prototyping in the USA: http://www.finelineprototyping.com/ I have been using Fineline for some years now and the quality of their prints are outstanding. They are not particularly expensive and offer a fast turnaround. The quality of their prints exceeds what I have seen posted in this thread. Geoff

This might be a little OT, but in the same vein. There has been some interesting discussion going on among US traction modellers on the Yahoo groups, regarding the use of a graphite solution. The particular product called 'Lock-Ease' consists of finely ground graphite suspended in a volatile liquid. The liquid is applied with a cotton bud to the track and overhead wire and spread around by running trams on the layout. Once the volatile liquid has evaporated, the graphite is left as a very light coating on both track and wire. Graphite, being a good electrical conductor, improves the contact between the tram pole/pantograph and the wire, as it does for the track. One would have to use it very sparingly on the track, as it is also an excellent lubricator, the prime use for the product. But the East Penn Traction Club has been conducting experiments with this material for some time now and they report that it works surprisingly well. They have not had to clean track for a long time while using it and report much improved running of the models.