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


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After seeing a thread on the old forum about 3D printing I decided to have a go myself. As recomended on here I downloaded a free cad drawing program and set about learning how to use the program. Here are the first results-

First I tried a class 24 roof.

renderedclass24roof.jpg

and developed that into a class 25/3 cab in 4mm.

2534mmfinishednewrooftallerbodyrece.jpg

most recently I had a go at a Class 24/5 bogie in 7mm.

25bogiesandboxsteps.jpg

I have just got some parts from the 3D printing company (shapeways as used by others on rmweb).

Class 25 cab 4mm tests

01042.jpg

Class 24 7mm bogie sideframe

DSCF0078.jpg

Final pic of the cab against a Bachmann body.

DSCF0093.jpg

Edited by simon br blue
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Hi Simon,

 

Is it the photos or are the castings a bit on the rough side?

 

I like the idea of decent cabs for Bachmann 25s as it seems to me to be the best way to get a decent 25. To my mind it's what Brassmasters should have done instead of just the cab roofs as the Bachmann cabs are the wrong shape. If you can get a decent quality product I'm sure you'll have lots of people wanting some. Personally I'd like 25/0 cabs most of all but the other types would be handy too.

 

Cheers

 

David

 

 

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Hi Simon,

If i may say so, your 3d rendering's look superb, not too sure about the 4mm castings however! The 7mm casting looks pretty fair though.

Unless it's the camera, perhaps - i've just had great difficulty photographing white H0 scale figures, not easy!

 

If that 4mm class 25 cab casting could be improved, then i think you have started to "make true" some of the predicitions in the "Noughties & Teenies" page!!!!!!

 

Could such a technique be used to create a really accurate replacement cab for the Heljan "Western", i wonder? (please!).

 

Well done indeed for having a shot at this, i certainly don't have the computer/drawing skills for this sort of thing.

Cheers,

John E.

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Hi Simon,

 

Is it the photos or are the castings a bit on the rough side?

 

I like the idea of decent cabs for Bachmann 25s as it seems to me to be the best way to get a decent 25. To my mind it's what Brassmasters should have done instead of just the cab roofs as the Bachmann cabs are the wrong shape. If you can get a decent quality product I'm sure you'll have lots of people wanting some. Personally I'd like 25/0 cabs most of all but the other types would be handy too.

 

Cheers

 

David

Are these castings, or are they built up in very thin layers as a sort of 3D printing? The complex shapes come out well. The surface finish looks a bit rough, but that should be fairly easy to fettle up with a bit of fine wet and dry paper. I'd certainly be interested to learn more about the process, including practical aspects like costs.

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Interesting stuff, may I ask who's kits are the 7mm class 25's in the background of the pics do you have any plans to actually produce 7mm parts to sell ?

 

Cheers

 

Phill

 

The 7mm class 24s and 25s in the background are Steve Beattie resin shells purchased from ebay.

 

DSCF57462.jpg

 

 

DSCF0098.jpg

 

I have got 8 bodies, some etched grills and some bogie castings. The quality of the steve beattie bogie detail castings are not too good so I might try to produce some resin castings (if I did I would need to get another sideframe printed with the details not attached to alow it to be cast). I would also like to try a class 25/3 cab in 7mm as the 25/3 in the picture is a modified 25/1 shell and I'm not happy with the windows.

 

The pic below shows a test of a 7mm cab profile printed in clear material to see how well it matches the Steve Beattie body.

 

DSCF7697.jpg

 

There are 4 different materials used in the pic above-

Right cab - white strong and flexible

Left cab - white detail

Bogie - Black strong and flexible

7mm cab profile- Transparent detail

 

DSCF7694.jpg

 

The pic above is a close up of the 7mm bogie to show the roughness of the surface. Looking at it in the flesh I would say it is fine for a bogie and the black material it was printed in gives it an almost dirty/oily finish and could be fitted to a model without painting. The cost of the sideframe in the black material was ??15.

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Interesting stuff Simon. you will end up with quite a fleet of Sulzers :icon_wow:,I like the work you have done on them so far (they are looking really good ) B) B) B). I think you must have out bid me on e-bay for one of the 25,1 body shells :icon_lol: . I was wanting to convert my Steve Beattie class 24 to a 25,1 as it doesn't really fit in with my BR(WR) theme & converting the original 24 body is a LOT of work ,I think the biggest stumbling block for me is the lack of cab headcode boxes on my 24 , so I have shelved the project for the time being . My 24 has brass bogies BTW which are quite nice, so perhaps Steve improved the kit before he withdrew it from the market (I believe Steve withdrew the resin kits because he could no longer get good enough quality resin ) .

I will be watching your projects with great interest...........Keep up the good work :icon_clap: :icon_clap: :icon_clap:

 

Cheers Phill :icon_thumbsup2:

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The class 24 roof could be rather useful. A little late for my current Class 24 project though -

 

DSCF1316.JPG

(Clicky!)

 

I think the 25/3 cabs would be very popular - it would be easier than sorting cabs from a Hornby body. Maybe Brassmasters have missed a trick by not producing these?

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I've used 3D printing as well. Off the machine, the parts do come out rather grainy, with some layering evident (this is inherent in the way the machines work, and a lot better than it used to be!). However, a blast of primer followed by some rubbing down usually gives a good surface finish. It does, I am finding, mean that you're better off leaving off rivet detail and adding it afterwards (unless you want some really fiddly rubbing down to do!) I've recently had a couple of wagon bodies prototyped as a test exercise (there's a pic of the raw body on my blog, will put more as the finishing and chassis construction progresses). I'm currently working on the CAD for a loco body for an industrial shunter (below), and will let you know how things go!

 

gallery_6528_679_27110.jpg

 

In terms of software, something like Google Sketchup is capable of producing the required files. There are other free packages available, but you tend to get less errors and issues with a high end CAD package. That said, if I didn't have access to one (Solidworks) in work, I certainly wouldn't shell out the couple of thousand it costs!! In terms of time, I find I can model something complex on the computer in a fraction of the time it would take me to scratchbuild it. Of course, it's not as much fun, but there's still a fair bit of work involved in the finishing and detailing process.

 

Apologies for hi-jacking the original thread, but there seemed to be a lot of interest in the technology, so I thought it would be worth sharing my experiences.

 

Alastair

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Hi Simon,

If i may say so, your 3d rendering's look superb, not too sure about the 4mm castings however! The 7mm casting looks pretty fair though.

Unless it's the camera, perhaps - i've just had great difficulty photographing white H0 scale figures, not easy!

 

If that 4mm class 25 cab casting could be improved, then i think you have started to "make true" some of the predicitions in the "Noughties & Teenies" page!!!!!!

 

Could such a technique be used to create a really accurate replacement cab for the Heljan "Western", i wonder? (please!).

 

Well done indeed for having a shot at this, i certainly don't have the computer/drawing skills for this sort of thing.

Cheers,

John E.

 

Cripes!!! well there you go... I didn't know it was presently possible when I predicted that - and the technology is bound to improve... I wonder what else I can predict. The 3.30 at Kempton perhaps :rolleyes:

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Are these castings, or are they built up in very thin layers as a sort of 3D printing? The complex shapes come out well. The surface finish looks a bit rough, but that should be fairly easy to fettle up with a bit of fine wet and dry paper. I'd certainly be interested to learn more about the process, including practical aspects like costs.

 

They are 3D printed in layers. For information about the process-shapeways.com

 

The surface finish seems to be the biggest problem with the process. In the pic below you can really see the layered effect.

 

DSCF7696.jpg

 

One of the other material does give a smoother finish but the detail level and minimum thickness of the material isn't as good.

 

DSCF7695.jpg

 

From a quick test I think it will be hard to smooth the material evenly, If the weather is ok later in the week I might try to paint a cab to see what the finish is like and then possibly try to sand and paint again afterwards.

 

A couple of problems with the proces i have found so far is that each material has a minimum wall thickness. white strong and flexible can be used to produce the thinest walls (0.7mm)but it is also has a rough surface finish. But even using white strong and flexible some details didn't come out- The first cab had a surround to the tail lights but when printed it didn't show up very well. It was hard when drawing the bogie to make sure all the shapes involved had a 1mm thickness in all directions. I was planning to model the pipe that runs along the side of the bogie but it would have needed to be to overscale to be able to print it and had the same problem with the brake rodding/equipment.

 

 

The costs are worked out with a set price per cm3 so the bigger the volume the more expensive it is (volume of the model not the dimensions of the model). The materials have different prices from 90p per cm3 (white strong and flexible) upto ??6.20 per cm3(for metal).

 

The cabs cost roughly ??15.

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Hi interesting stuff there. I take it these are being printed using shapeways? I've used this company myself for a couple of years getting a feel for what is possible using 3D printing. N gauge requires alot of though in the design phase in order to produce something that can be cleaned up without destroying the print but I would gather this isn't so much of an issue cleaning up a 4 or 7mm part. Recently I've tried SLA (laser cured resin) somewhat more expensive (around 10 times the cost!) but the initial results are much finer and therefore less cleaning up involved. As a comparision I've attached a picture of my LNER K3 body which was printed using SLA - the loco is in grey primer while the tender is in it's 'raw' state.

 

post-943-12645922209386_thumb.jpg

 

What CAD program are you using? I've found that the basic version of Alibre Design is a good entry point into 3D modelling and able to produce most shapes with a little thought.

 

Looking good and I'm watching with interest what you produce next.

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Another interesting topic, getting me very tempted to fire up solidworks and start drawing up some wagon bits.....

The SLA resin stuff looks even more promising as well!

 

Will just need to brush up on the program now as its been a few years since I last used it....

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Hi interesting stuff there. I take it these are being printed using shapeways? I've used this company myself for a couple of years getting a feel for what is possible using 3D printing. N gauge requires alot of though in the design phase in order to produce something that can be cleaned up without destroying the print but I would gather this isn't so much of an issue cleaning up a 4 or 7mm part. Recently I've tried SLA (laser cured resin) somewhat more expensive (around 10 times the cost!) but the initial results are much finer and therefore less cleaning up involved. As a comparision I've attached a picture of my LNER K3 body which was printed using SLA - the loco is in grey primer while the tender is in it's 'raw' state.

 

post-943-12645922209386_thumb.jpg

 

What CAD program are you using? I've found that the basic version of Alibre Design is a good entry point into 3D modelling and able to produce most shapes with a little thought.

 

Looking good and I'm watching with interest what you produce next.

 

Atso, any chance of a high resolution post of that K3 body in N. I followed your old Rmweb threads with great interest but I'd kind of lost touch in this new forum. I was extremely interested in your progress.

 

This and all the work in this thread is really quite exciting. The thought of what could be achieved is mind boggling.

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I'm very intrigued by this. What CAD software did you use by the way?

 

I use a program called Blender. The reason I chose it was because it was free. It's not too hard to master and the best way is to watch tutorials on youtube. Then start off with something simple like a loco roof or part of a car. The most important thing is to get some good drawings of the prototype (Side, end and roof) to work from. I got the drawings for the bogies from the National Rail Museum archive when I visited the museum last year.

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Have to say I found this thread fascinating, particularly because the 4mm class 25 does need serious attention in certain quarters, as well as my 2nd choice of diesel the class 40.

 

My first thoughts were - how fantastic, but the finish is a very minor let down, but I am sure quality will improve, and wet and dry should sort many of the "problems" anyway.

 

I am really looking forward to seeing further results of this medium - keep up the excellet work.

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Guest jim s-w

Excellent!

 

You seem to have got the shape very nicey indeed. As for the finish I wouldnt say thats a show stopping problem. Is it the size thats a problem? As the cabs would most likely be used by people doing reasonably drastic surgery have you considered producing the cab as 4 parts rather than a complete unit?

 

Cheers

 

Jim

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I believe one way 3d moulds are used is the 3d print is used to make a negative mould, which then makes a positive part, which is then cleaned up and used. I have a feeling some go through two or three positive/negative stages before the final thing is produced! Then again, that's probably mainly if you were to be producing a final mould for injection moulding thousands of them.

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Guest jim s-w

I believe one way 3d moulds are used is the 3d print is used to make a negative mould, which then makes a positive part, which is then cleaned up and used. I have a feeling some go through two or three positive/negative stages before the final thing is produced! Then again, that's probably mainly if you were to be producing a final mould for injection moulding thousands of them.

 

Most injection moulding uses spark eroded machine tools. You wouldn't take a mould off a master these days.

 

Cheers

 

Jim

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Most injection moulding uses spark eroded machine tools. You wouldn't take a mould off a master these days.

 

Cheers

 

Jim

 

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.

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