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Loco Wheels


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I just saw this Group at the bottom of the page and I thought that I would ask this question that I have thinking about for a while. Is it possible to build steam loco wheels using 3D printing and would you have to learn CAD to do It?

Regards

Len Cattley

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Len,

 

Would these be carrying wheels or driving wheels? Don't forget you'll need a rim that will conduct electricity.

 

From my experience if you want them for live steam, best get them cnc'd in steel or cast in ironlaugh.gif

 

Regards

 

Richard

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I think it would work rather well for making a specific kind of centre (spoke shape, spoke quantity, or crank boss) but the tyre would need to be turned afterwards and the centre bored out to suit the axle.

 

You could have them 'printed' in metal but it will be £££s.

 

To answer the other question: you will need a 3D CAD file to send to the 3D printers, however a locomotive wheel will be quite simple and should not take very long to produce from dimensioned drawings.

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I've been looking into this too for some N gauge wheels. I think printing in wax/fud and the brass casting would be a better solution to direct metal printing. Obviously the investment brass casting would need some modest machining needed to ensure that the final wheel is completely round.

 

For electrical isolation a plastic bush could be used between the wheel and the axle much as Farish do on their locos.

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I've been looking into this too for some N gauge wheels. I think printing in wax/fud and the brass casting would be a better solution to direct metal printing. Obviously the investment brass casting would need some modest machining needed to ensure that the final wheel is completely round.

 

For electrical isolation a plastic bush could be used between the wheel and the axle much as Farish do on their locos.

I'd like to think it would fill a gap in the market. :) I know I'd be interested.

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This is interesting, I'm currently looking into doing wagon kits and don't no what to do about wheels. I was considering asking the question on here about producing N gauge wheels. This could also mean that we can have fine flanged prototype wheels.

I was thinking about 3D printing centres and getting types turned. My main concern is getting high quality and precise axles.

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I think it would work rather well for making a specific kind of centre (spoke shape, spoke quantity, or crank boss) but the tyre would need to be turned afterwards and the centre bored out to suit the axle.

 

You could have them 'printed' in metal but it will be £££s.

 

To answer the other question: you will need a 3D CAD file to send to the 3D printers, however a locomotive wheel will be quite simple and should not take very long to produce from dimensioned drawings.

 

 

Would the National Railway Museum have the drawings for driving wheels?

Regards

 

Len

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  • 10 months later...

Bill Bedford has prototyped some wheel centres using 3D printing.

 

Production is now underway.

 

One thing to note: the axle holes / seats should ideally be a snug fit on the axle - you don't want a situation where it's possible for an axle to slip right through the wheel centre without stopping!

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Missy of this parish has done some in 2mm scale and they look pretty good - we won't say who dropped one of them on the floor at Railex.

Would that be a Mr Equinebeige*? :jester:

 

* - Names have been amended slightly to protect the guilty...

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Hi,

You would need to learn 'a' CAD system to be able to design something suitable for 3d printing. There's many out there, some free, some paid for, some easier than others of course. My learning curve has been through using Google Sketchup,and I've found it pretty straightforward to pick up - if not entirely designed for 3d printing, or indeed 3d printing of the sort of dimensions we're looking at as modellers.

 

I wouldn't go for a set of wheels as a first design though, maybe start off with something square and straightforward to get into the techniques and work up from there?

 

Regards

 

Richard.

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  • 2 weeks later...

For round parts like wheels I use openscad. It's pretty trivial to whack out basic disc, three hole etc wheel types as the are basically a lot of cylinders and cone slices around a common axis. Has nice scripts for printing gears and the like as well although in N where I work the gears aren't usefully printable .. yet ...

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I've been observing the behaviour of 3D-printed centres (Bill Bedford's) when unpainted and exposed to sunlight. There is a definite yellowish tint appearing after a couple of weeks.......

 

Immaterial since they will be painted, but interesting phenomenon all the same :mail:

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I've been observing the behaviour of 3D-printed centres (Bill Bedford's) when unpainted and exposed to sunlight. There is a definite yellowish tint appearing after a couple of weeks.......

 

Immaterial since they will be painted, but interesting phenomenon all the same :mail:

 

I had some prototypes made for work that change colour to be quite orange when out on the desk (exposed to sunlight) and back to a dull light yellow when left in the drawer (or away from sunlight) overnight. If painted then it's not going to be a problem.

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Hi Laurence,

 

I don't think this would be possible yet due to alignment issues - at least unlikely with a home setup. You could try to convince a 3D printing firm but I'm sure, if they agreed, they'd charge though the nose for it...

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Would it be possible to print the centre into a pre-turned tyre?

No. Almost all machines have a device which sweeps across the bed to fix the thickness of the layers. Having a chunk of metal on the bed would cause havoc to the machines. The exceptions are the FDMs (aka RepRap types) which could possibly do something like this, but their resolution that you wouldn't want to print wheels with them.

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  • 3 weeks later...

Hi Laurence,

 

I don't think this would be possible yet due to alignment issues - at least unlikely with a home setup. You could try to convince a 3D printing firm but I'm sure, if they agreed, they'd charge though the nose for it...

Just an idle thought.

Laurence

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The accuracy of rapid prototyping is such that it should be possible to print a centre to be a push fit into a pre-machined tyre, and maybe even use Slaters' square-ended axles for quartering too. There may be a bit of mucking around getting the fit precise, but once done it should be repeatable. There are some tricks that can be used, such as a chamfer on the edge of the wheel centre to help it enter cleanly into the tyre.

 

I have some O-scale 3'6" gauge freight wagon wheel centres being done in FUD right now to test the technology, see screenshot below, will post results of attempting to fit tyres here when they are done. The tyres are made in New Zealand by North Yard, cheap as chips. I picked on wagon wheels so as to keep the cost down, plus a friend had already given me a set of tyres. The end goal is to produce r'p'ed wheel centres for various obscure NZ steam locos which don't cost the earth.

 

 

Regards, Paul.

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The accuracy of rapid prototyping is such that it should be possible to print a centre to be a push fit into a pre-machined tyre, and maybe even use Slaters' square-ended axles for quartering too. There may be a bit of mucking around getting the fit precise, but once done it should be repeatable. There are some tricks that can be used, such as a chamfer on the edge of the wheel centre to help it enter cleanly into the tyre.

 

I have some O-scale 3'6" gauge freight wagon wheel centres being done in FUD right now to test the technology, see screenshot below, will post results of attempting to fit tyres here when they are done. The tyres are made in New Zealand by North Yard, cheap as chips. I picked on wagon wheels so as to keep the cost down, plus a friend had already given me a set of tyres. The end goal is to produce r'p'ed wheel centres for various obscure NZ steam locos which don't cost the earth.

 

 

Regards, Paul.

 

My son produced some 3d printed wheel centres for an obscure loco in 4mm scale and we did them dead same size outside diameter as the inside diameter of the tyre we were using (no allowance for interference fit) - they pushed straight in and ran very true on 2mm axles - a drop of loctite was later added just in case. But I should point out that though they were for a driving wheel, the strength of the 3d printed material was not exploited with traditional coupling road as the axles were gear coupled.

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  • 1 month later...

Hi All

 

Finally managed to figure out how to upload photos more or less by accident - IMHO, the help section is completely hopeless, could not find anything like basic how-to instructions anywhere!

 

Anyhew, here is a photo of my rapid prototyped wheel centre fitted to a NorthYard tyre (made in NZ). After reading Shapeways' guide as to shrinkage of frosted ultra detail, I took an educated guess as to size, and the result turned out to be a perfect firm press fit. Very exciting, as this means I can produce an accurate replica of any NZ railway wheel which was hitherto rather difficult, especially in 9mm:ft scale.

 

Regards

Paul Woods

Whangarei, NZ.

 

post-13024-0-19937900-1346657450.jpg

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