3D printing class 25 parts .... Also class 20,37, 2mm and 7mm wagons and 1/32 bogies

[simon br blue]

I have given the cab a coat of paint and a sand and it does look better (I only sanded the lower cab front so that the original finish can be seen on the windows and roof). Another sand and paint and I think it would be ok. the other option would be to make a resin copy of it, sand detail and paint that and then use that as a master for some 25 cabs.

 

[hollywoodfoundry]

Hi Jim,

 

When I was researching 3D printing, I found that it is possible to print a steel injection moulding tool using a form of SLS with very fine steel powered rather than nylon sintered using a laser. The resulting print could be blasted and polished to around 99% perfection. Obviously at the moment the technology is somewhat pricey (around ??2000 for a small mould) but I'm sure within a few years this would be the way to get low cost tooling made.

 

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

[Atso]

Hey Simon, looking good. Is that cab printed in strong white and flexible? If so you've done a good job sanding it down, I always seem to over-do it!

 

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

 

Geoff,

 

Some interesting stuff there and also interesting about the injection moulding process - I'm going to have to investigate this further now....

 

Also thanks for the link to Fineline, I'm sure the growing community of 3D railway modellers will find this another usful resource! I've just checked it out and although the price is around 5-8 times that of Shapeways the quality (as you said) appears to be much much higher. Do you have any pictures of detailed items you've had produced using Finelines?

 

Cheers

 

Steve

[craigwelsh]

Also thanks for the link to Fineline, I'm sure the growing community of 3D railway modellers will find this another usful resource! I've just checked it out and although the price is around 5-8 times that of Shapeways the quality (as you said) appears to be much much higher. Do you have any pictures of detailed items you've had produced using Finelines?

 

Cheers

Steve

Did you contact them to get some prices or find it somewhere in the site? I couldn't see any approximate costings.

 

I would like to see something you've had done by them Geoff as well as info on what material and process you used.

 

There are some great possibilities with this for areas that can't be covered by etching well. The class 25 cab looks great for example so if it could be done by a finer process it would be marvellous.

[Atso]

Did you contact them to get some prices or find it somewhere in the site? I couldn't see any approximate costings.

 

If you look at the top right hand corner you'll see a link 'Get a Quote' you can then upload your models in a similar way to Shapeways and get costings.

[craigwelsh]

If you look at the top right hand corner you'll see a link 'Get a Quote' you can then upload your models in a similar way to Shapeways and get costings.

Yes i'd seen that, I was rather hoping though you'd found a page with a couple of example objects with pricings for them.

 

I'll have to do some drawing and see what they come back with.

[hollywoodfoundry]

I would like to see something you've had done by them Geoff as well as info on what material and process you used.

 

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.

[hollywoodfoundry]

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

[craigwelsh]

The fact you've managed to cast off that in lost-wax is great news as axleboxes is something I was looking at.

 

I found the material sheet on the website although its red there http://www.finelineprototyping.com/datasheets/prototherm12120.pdf so i'll have to have a go at some designs.

 

Have you done anything curved like the class 24 cab roof shown earlier in this material? It does seem to step a little still at shallow curves but much better than Shapeways method. The price sounds ok too really.

[David Rickard]

I found this purely by accident today:

 

http://objects.reprap.org/wiki/Main_Page

 

Build your own 3D printer for about ?‚¬350!

[hollywoodfoundry]

The fact you've managed to cast off that in lost-wax is great news as axleboxes is something I was looking at.

 

I found the material sheet on the website although its red there http://www.finelinep...otherm12120.pdf so i'll have to have a go at some designs.

 

Have you done anything curved like the class 24 cab roof shown earlier in this material? It does seem to step a little still at shallow curves but much better than Shapeways method. The price sounds ok too really.

 

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.

[Atso]

Awsome stuff there Hollywood! I think that despite the extra costs involved that this is the way to go!!! B)

[simon br blue]

Quick update-

I've not ordered anymore prints yet. I've looked at the fineline site and tried a quote and got a message that they're not taking on new customers from the UK but got directed to a UK company that works with fineline so I'll have to speak to them when I get time.

 

I have also modified the basic cab to produce a class 25/1, 24/1 and 24/0 (although the 24's are not finished yet and still need the bufferbeam skirt/valance adding).

 

 

 

 

I have also made a class 40 bogie sideframe that I can hopefully use with a brass body purchased from ebay and a pair of MMP resin cabs.

 

[dave_long]

You've certainly got some 3D art talent they look great.

 

kind regards 

 

 

[djparkins]

I have also made a class 40 bogie sideframe that I can hopefully use with a brass body purchased from ebay and a pair of MMP resin cabs.

 

The only problem I'd say with using this process to produce something like a 7mm Class 40 Sideframe in one piece is that you get that 1960s 'Triang' look with things like the leaf springs, which obviously should stand off from the bogie side and is very noticable in 7mm.

 

Regards,

 

David Parkins,

Modern Motive Power

[craigwelsh]

The only problem I'd say with using this process to produce something like a 7mm Class 40 Sideframe in one piece is that you get that 1960s 'Triang' look with things like the leaf springs, which obviously should stand off from the bogie side and is very noticable in 7mm.

Its better than 2010 Heljan though, at least it retains some depth compared to their very flat detail. They may have improved things with their 7mm releases though. Maybe you could mould the springs separately though the hangars may be a bit flimsy?

 

Could you give that cab to Bachmann and maybe they'll get future N gauge releases right instead of using a shrunk 4mm one .

 

Please do keep us informed how you get on with that UK arm/liason of Finelines. Their models did look a lot finer than Shapeways and i've now got access to Solidworks to have a play (after i've sent off more 2D Cad anyway ).

[djparkins]

Maybe you could mould the springs separately though the hangars may be a bit flimsy?quote]

 

Well exactly - the point is whether or not it is best to construct items like this in 7mm from metal components, otherwise you can end up with over-thick items that look too thick, just so as to get some structural strength into them. I would not say that the sideframes on 7mm Heljan locos are that convincing either.

 

David Parkins

[Pugsley]

Well exactly - the point is whether or not it is best to construct items like this in 7mm from metal components

I guess that in turn depends on whether the part you're building is structural or cosmetic. In the case of the bogie sideframes, If they were to be structural in the same sense as the real ones, then they would definitely have to be metal. If your inner bogie structure was made from etched parts and the sideframes were purely cosmetic, then it doesn't matter, IMO.

 

I agree that separate springs would look better, but if it was me designing it, then the sideframes would be structural in the same way as the real thing, and the springs would work like the real thing as well!

 

Simon - Nice work on the 3d modelling BTW B) B)

[hayfield]

I guess that in turn depends on whether the part you're building is structural or cosmetic. In the case of the bogie sideframes, If they were to be structural in the same sense as the real ones, then they would definitely have to be metal. If your inner bogie structure was made from etched parts and the sideframes were purely cosmetic, then it doesn't matter, IMO.

 

I agree that separate springs would look better, but if it was me designing it, then the sideframes would be structural in the same way as the real thing, and the springs would work like the real thing as well!

 

Simon - Nice work on the 3d modelling BTW B) B)

 

I have a friend who is a jewler and has just brought a machine that prints very finely in wax, to make moulds for casting. It was very expensive and not the type of machine a modeller would buy. When he gets time he plans to make some parts for his locos. Cost would be prohibitive as you would have to pay for the master to be printed then the mould making and casting process.

[Pugsley]

That does sound interesting, how expensive is very expensive?

 

You could use the technology already shown in this topic to do the same, but with the added intermediate step of creating a mould from your printed master and then using that to create the wax forms for lost wax casting.

[hayfield]

That does sound interesting, how expensive is very expensive?

 

You could use the technology already shown in this topic to do the same, but with the added intermediate step of creating a mould from your printed master and then using that to create the wax forms for lost wax casting.

 

I think its about £20,000, not seen it yet but after every layer is printed it cuts the print flat (and hovers the cuttings up), then layes the next print. A slow process but makes a very fine master. It depends on the size but it sometimes takes several hours to produce the item. I should realy go round and see the piece of kit.

[Pugsley]

Yes, it is very expensive then! I had a feeling that you were somewhere in the 5 figures range - it sounds very good though. Your friend could have a lucrative sideline to the jewelry business if he can run the machine 24/7

[hayfield]

Yes, it is very expensive then! I had a feeling that you were somewhere in the 5 figures range - it sounds very good though. Your friend could have a lucrative sideline to the jewelry business if he can run the machine 24/7

 

For the work he is doing its running a good part of the day, whilst it is worth it for makeing high value items on the railway side I doubt if the economics are there at the moment other than for ones own pleasure. No doubt at some point in the future prices will fall, but once you have a master you will have to have a mould made, then get it cast.

[hayfield]

My friend who has the printer brought some samples of rings he printed. His machine prints in wax and they produce high quality wax masters from which moulds can be made, with little of no cleaning required. He is trying to think what he could print (or is it grow) for use in his model railway just for the hell of it.

[Atso]

Hi John, sounds like your friend has bought s Solidscape printer. I've hear very good things about this and plan on using one for my own kit project.

 

Most of the problems with 3D printing is getting suitable resolution and fine build layers. This then creates more work finishing the print to make a usable master. Solidscape claim to be albe to obtain a resolution in excess of 4000dpi and a build layer of only half a thou at its finest settings. Obviously cost per print is somewhat expensive but having viewed some of the prints this type of machine can produce personally, I firmly believe that you'll get what you pay for.

 

As a side note, I think 'print' would be the correct term for this machine as it deposits the wax layers in a very similar way to a inkjet printer.

 

Maybe your friend may consider doing modelling prints as a side business as well?