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3D Printed N Gauge Pendolino and On Track Plant

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This should look really special when you complete it, but of course you know what will pop up at Warley don't you or are you deliberately tempting fate. Now these have more than one livery it may tempt them to take the step.

 

Maybe David's "taking one for the team" here: sacrificing his time (and £17) in the certain knowledge that one of the RTR manufacturers is now guaranteed to announce a complete set that we can all benefit from...

 

Jim

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I'm quite excited now, my Shapeways order has been dispatched, and on Monday I can see how my designs have turned out . Astonishingly, the ropy driving car passed and is also on its way!

 

I'm not expecting magic, but at least I can get a feel for how the designs translate into reality - what level of detail shows up,what flaws need correcting etc. and also experiment with glazing and paint.

 

Watch this space!

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Hi David,

 

I've only just seen this thread, If you decide to sell these through shapeways put me down for a couple of rakes. What you've done so far looks excellent!

Following with great interest.

 

Graham.

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I admire your bravery in tackling something like this, as a 3D design novice, and I'm looking forward to see what turns up from Shapeways. That's quite a challenge you've set yourself!

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Well my bodyshells have now left the Netherlands, and bizarrely are going via Germany to get here, but in the meantime, I've had a go at creating a full piece body - complete with underside and bogie bumps (no idea what these connecting bits are called, but all old farish coaches have them to clip the bogies into!).

 

post-6666-0-15351300-1348930781_thumb.jpg

 

If this works, this will save having to chop up coaches, but I need to see how rigid the material I've printed in is, as I don't want any twist or warping. I'm still not certain about the windows. Part of me is now thinking to simply create shallow pits rather than full openings and drop in black opaque plastic - the tint is so dark there is little point having apertures in the first place as you wont be able to see inside anyway.

 

The nose design I grafted onto my own design I've noticed isnt actually a very good shape, so I'll use that car for experimentation and painting tests, then look into laser scanning the Hornby nose to get a better shape.

 

David

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Do any of the 3D printing sites offer clear material that you could use for the windows?

 

Happy modelling.

 

Steven B.

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Guest jim s-w

Good work David

 

I have absolutely no idea that this will work but what about printing solid windows and painting them silver, followed by an almost opaque black and then gloss varnish?

 

In responce to the Hornby APT and scale curves - it doesnt tilt! :)

 

Cheers

 

Jim

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Hi David

 

I tend to think that Jim's idea for a glazing strip for each coach has merit; and being CAD designed it should be a nice snug fit. Having it as a separate component will add cost, but make painting the model a lot easier.

 

Your design is coming on very well too, and I think moulding a whole body is probably a better solution to using Farish Mk4s.

 

Looking at your design for the trailer cars, and still obsessing a little about tilt, I did wonder if either side of the bogie pivot (sometimes called the "boss") you could add a curved sloping recess (like an inverted wedge) that slopes up toward the inner end of the coach. If short pins were fitted to the either side of the bogie cross member, and arranged to support the coach body then in the straight position the coach would sit level, but on a curve, as the bogie rotates, the pins on the "inner" side would move toward the centre, and into the graduating wedge recess. The coach body will then lower on that side only, creating the illusion of tilt.

 

I agree this may be a little overcomplicated, and unnecessary, but I thought it worth a discussion before you finalise your design. And it's not irreversible; if it doesn't work after all, then removing the pins from the bogie effictively isolates the system.

 

cheers

 

Ben A.

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Guest jim s-w

Hi Ben

 

I was actually thinking, if the technique worked, you could print the whole thing with windows in place.

 

Cheers

 

Jim

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Hi guys,

 

I uploaded a solid window version to Shapeways for a costing and it was surprisingly expensive. Whether their system now things its just one big solid piece I'm not sure.

 

What I'm looking at now is a 0.2mm recess around the window aperture so I can fix opaque dark plastic into the gap - and I will try laser cutting these so they are a snug fit. I will certainly try Jims idea.

 

David

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Hello David,

Congratulations with your pendolino, it looks superb from the cad drawings. On the mention of the high price once the new file was uploaded, this is probably because it is reading it as you suggested as one piece, (if you have no openings anywhere else this will be the case, a way to cure this would be to open the holes on the bogie pivots or "bosses" all the way through into the inside of the coach to allow the file to see it is hollow, And to allow the support wax to escape.

Hope this is of use, and looking forward to your first samples,

Regards,

Wild Boar Fell

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Hi David;

 

Sounds like a fantastic project with lots of interested individuals (including me) looking forward to the results.

Give me a shout if I can help in any way.....probably a 158/170 chassis is a good starting point for motorisation...like you say, bogies can come later.

 

Perhaps mould the underbody as a separate entity to become a replacement clip/glue fit to the chassis...and keep the bogie pivots in as structural rigidity.

 

Later;

STU in KOQU

(Back in UK 2moro) :O

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Hi David

 

My reasoning around making the glazing units separate (even if they are moulded solid) is to make it easier to paint them to look different to the surround, and reinforce the illusion that they are clear but heavily opaqued.

 

Having said that, a single piece moulding is more straightforward.

 

cheers

 

Ben A.

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Particularly if using polished WSF (so its a decent strength/price) I'd actually be inclined to make the entire black window area a single cut out and then cut a tinted glazing strip to fit (remembering the black goes beyond the windows a bit all around so you don't have to aim quite straight and then vinyl over it.

 

That I suspect will also make it a *lot* easier to paint. Also as you can get black vinyl you can cut it without printing and thus without white edges.

 

For the full piece body remember that you've got to be able to paint inside and assemble it so there has to be a join somewhere. Pendolino 'hide the join' looks less simple than most.

 

Re tilt - tilt wedges are completely configurable, they don't have to be a flat wedge but an arbitrary profile which means you can set the vehicle to hit maximum tilt at say 15" and continue the same tilt level as it nips around the 9" curves into the fiddle yard. APT would be easier to model this way because if one coach sticks the wrong way now and then it'll at least be prototypical 8-)

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Very excited today, as the Shapeways boxes turned up.

 

I am really blown away by the quality of the print, and this test has really shown me where to go with this project next. I'm focusing on far too tiny details in the designs - when in the screen you forget exactly how small all this really is, so worrying about a 0.2mm inset just really isn't worth it.

 

Here are the washed shells as delivered. The pantograph car has come out extremely well, while the driving car, while a bit of a mess as expected, has actually come out better than I had hoped for, and at least I can now see how the complex 3d shapes actually come out in reality.

 

post-6666-0-15767400-1349115226_thumb.jpg

 

Next the pantograph car with some grey primer, looking very snug on the cut down mark4 chassis. This has now been changed in the design with an all in one bodyshell.

 

post-6666-0-57982500-1349115351_thumb.jpg

 

The next photo shows my big problem though - due to the tapering sides, the 170 chassis doesnt quite fit so the body sits too tall. I need to think carefully about this, as I'm going to have to find a good compromise between the accurate profile, and the space needed to accommodate a power chassis.

 

post-6666-0-50769700-1349115378_thumb.jpg

 

And finally, very quickly sprayed up, so forgive the awful painting (this is all just a test run!), can you guess what it is yet....?

 

post-6666-0-47667200-1349115410_thumb.jpg

 

Next steps are to solve the powered chassis issue, and have a look at the driving car. My 3d model making course starts tomorrow, so over the next ten weeks I hope to l learn plenty of new skills to help improve on this, but I'm actually very pleased how this has gone as a first stab at 3d printing.

 

David

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That is very good David You could try the TPM MUM Chassis

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This is very impressive David. I must say that you modelling using CAD and 3D printing is something that is bound to produce some very interesting models.

 

In relation to the glazing, there are a couple of things you could consider. First is to use laser cutting to produce exact size plastic inserts for the windows. These would be tricky to fix but could definitely be a solution if you just wanted to produce a train for yourself. Taking this a bit further you could produce a "sprue" with all of the windows for one side drawn out and laser cut them from clear styrene. I am not sure how viable that is but it might work.

 

Doesnt one of the Kato EMU's (the one that looks like a javelin) have a tilt mechanism? Would you consider buying one of those units to use as a donor for your Pendalino project?

 

Whatever you do, good luck with it and I would be very interested to hear any details about the course.

 

Stephen

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When thinking about making the black window surround as an insert, remember this is just a livery feature. Depending on the deliberations of m'lud they could be appearing in a totally different livery in six months time, and it would be a shame if this remained like the famous moulding line that separated the shades of green on the blue Hornby 47! How about painting the whole side to represent window as suggested by Jim, then applying a vinyl?

Edited by Edwin_m

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Thanks guys,

 

I did think about the Dapol chassis, but the low slung motor means you can't get the profile for the sloped under frame boxes etc. The older Farish 158 chassis is a tight fit but looking at the coach compared to the 158, 170 and 220, I think ive actually made it slightly under scale, so I will revise the cad drawings to add about another 3mm or so to the height, which should give just the extra height needed.

 

For windows, all I did on the mock up above was to stick a sheet of darkened clear plastic behind the openings. It's not flush, but I will try several options here, including simply having an inset for an acetate sheet then sticking vinyl over it as suggested. Another option is to thin down the inside of the window area to 0.7mm, so although still quite a big scale recess, the acetate behind the openings will be visually extremely close to the outer surface, giving a better appearance than above.

 

My preferred option if it works though, is to laser cut exact shapes out of darkened plastic, then have a layer of clear plastic behind, so they can basically drop in and stick to the layer behind. These can be opaque really as the real windows are very dark anyway so you can't really see in.

 

Next steps are to rescale the height and width slightly, then decide on the best window approach, then probably take the plunge and order a set of intermediate coaches - I really need to double check the version with the all in one body, to make sure the bogie pivots work ok, but given the postage and packing is £10 per order, as the coaches only cost £12 each to print, it's far more economical to order in batches

 

David

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..................it's far more economical to order in batches

 

David

 

Welcome to my world..............................

 

As for the enclosed version being more expensive, the cost is based on volume of material. If you have not left an opening, they will assume it is solid. Or it could simply be that you have fairly thick bits. For example, is the belly part hollow, or is the floor level. If it is solid, that is a lot of material. If you haven't done so, think of making it hollow from either the bottom, or by dropping the 'floor' where required.

 

I am currently looking a different method of providing a better finish to WSF, which will improve the ability of vinyls to stick.

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Take a look at Bernard's TPM chassis for 20 and 23m lengths. It's designed motorising Mark 1 and Mark 3 coaches and is clear below floor level.

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Hi David

 

You must be delighted with the progress so far - for "first drafts" the two cars you've had printed so far are amazingly good.

 

I'd second the suggestions from others that you look at the TPM motorising unit - I wonder whether the 170 mechanism won't fit because the Pendolino profile is tapered to ensure the cars don't go out of gauge when they tilt...

 

Really enjoying this thread and looking forward to ongoing progress.

 

cheers

 

Ben A.

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Thanks Ben, yes the 170 has a square profile chassis, while the 390 is much more tapered. I've ordered a new print of the complete all in one bodyshell, but rescaled to be just over 1 mm taller - this should give enough room for the chassis, though obviously as this is the all in one shell, I won't be able to test it on that.

 

This new shell is to test the under frame boxing, and most importantly, the bogie pivots. As this is an expensive process, I need to do as few test runs as possible, so if I can crack the bogie pivots on this, and compare the shell to the previous one to double check the extra 1mm would accommodate the chassis (which it should, and it not, I will look at the TPM one), I can move on swiftly.

 

David

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