3d printed GWR coaches - something big...a D51

[The Great Bear]

After a few hiccups with the printer back to printing some more coaches

 

Firstly something different. With some Hornby 57' bow ended suburban coaches on order, to make up the 5 car London division set that did a couple of services on my layout, I need a random all third non-corridor coach. So I have had a punt at a C25. This diagram had a clerestory style body but with a different roof, without the clerestory. So I made up a new bodyshell, using dimensions from an article by John Lewis in an old Model Railway Constructor Annual.

 

 

Rather annoyingly this coach is an extra foot longer than the toplights at 58' which meant it is even tighter to fit in the build space I have, indeed didn't quite all come out (see bottom right corner). But it will serve my purpose.

 

 

I also reduced the size of the supports required for printing at the end of the coach, so their remains are less visible. The photo shows I haven't managed to completely sand them down but it's better than previous efforts. I've also removed the moulded jumper cables idea being to use some thin wire for the cables. Also the moulding for the alarm gear allows for threading a wire through to complete that.  In printing these I also increased the twist of the model around its longitudinal axis to 30 degrees which seems to have gotten rid of the small amounts of stepping on the tumblehome still visible in the previous few prints. In these prints I have marginally thinned down the body sides, the width behind the droplights being the constraint. I also tweaked the bollection detail to give a more prototypical shape tapering in to the glass I believe.

 

Here's a similar approach on the end of a C30 Toplight

I have also left the corridor off, but for me the printed corridor works so am printing some separately. I think what's shown is a reasonable balance between moulded bits and stuff to be added later?

 

So I'm pretty happy and think I've got as good a result with the body as I'm going to get.

 

The underframes remain a challenge, more on that soon.

 

All the best

 

Jon

 

 

 

 

 

 

 

[jamespetts]

Those look very good. May I ask - how do you sand these so as to get the ridge effect out in the recessed parts without sanding away the beading entirely?

[The Great Bear]

On 14/03/2019 at 23:58, jamespetts said:

Those look very good. May I ask - how do you sand these so as to get the ridge effect out in the recessed parts without sanding away the beading entirely?

 

That's a good question, may be I'm better off placing supports on the panels not the beading! Just need to be precise with sandpaper...

[The Great Bear]

Printing my own bits I've struggled with the underframes, warping being a problem. My latest attempt at fixing this is rather crude, adding stiffening beams t and then post curing the model for a long time over an hour under uv lighting. Only when that's complete do I remove the beams. Seems to work so far, holding shape once beams are removed.

 

 

 

Do to fragility I'm also not printing the buffers and draw hooks in place but as shown. This would also allow for fitting alternatives. Battery box positions vary between individual diagrams so by printing three covers this, then snip off the one not needed.

 

If this works then just the issue of end supports as per post above to resolve really...

 

Jon

 

[The Great Bear]

The C25 was a stepping stone to a clerestory, as has the same body profile and details. So here's a C23.

 

Based on one of the examples in Russell, I deleted some of the paneling to represent a coach in its last days.

 

 Trying Halfords filler primer again, I was perhaps a bit heavy handed (again) with it.

 

 

I have quite a backlog of coaches to finish now, but this one will jump the queue as a quick win in wartime brown to go with the Collet non-corridor coaches I bought to make a 5 coach set.

 

A corridor clerestory will be tje next project.

 

All the best

 

Jon

 

 

[darthmh]

I'm not sure if you are aware of this or if it is old news but a friend of mine makes 3d printed models for wargaming and he does something called Ironing.  Its a setting on his printer that goes over the top layer and slightly melts it giving a much smoother finish.  Not sure if this is something that may help get a better surface. (if you machine has the setting)

[amandalee]

Hi..Its a setting in Cura..the open source slicing programme. It adds a little time but the finish is worth it on flat areas.

[The Great Bear]

3 hours ago, amandalee said:

Hi..Its a setting in Cura..the open source slicing programme. It adds a little time but the finish is worth it on flat areas.

 

I don't use Cura, I use ChituBox for slicing. I think that setting is only applicable to filament PLA type printers whereas I am using a resin printer. I do enable anti-aliasing in the slicing software which smoothes surfaces especially curved ones helping (along with angling the print) to avoid stepping.

[The Great Bear]

Some more coaches. Firstly a D88 brake third:

This print shows the end that is nearest to the build plate when printing. I haven't made an attempt to clean up the printing supports, but by reducing the size of tips of them they should with care clean up easier, with less damage to the detail at the end.

 

Next, some corridor celerestories, firstly an E73 composite:

 

This, unlike the photo of the E88, is the free end of the print, so no supports.

 

The chassis remain a pain to print, to avoid warping as mentioned above I print attached to stiffening beams then cure for a long time an hour plus and only then remove the supports. The downside is that the resulting print is very brittle - you can see where I snapped it in the photo. For the toplight frames I'm erring toward printing via 3rd party using SLS Nylon or HP Mutlijet fusion tech, they are then more robust. More on this later.

 

Some coaches like this one, the location of the bogie centres ends up rather messily fouling the seats, but who's going to see...

 

And finally for now, a completed coach a C17 all third

Most of the pictures of clerestories in Russell show them in all brown livery, which suits me - far less painting and lining to do. This one has a stab at some weathering too.

 

All the best

 

Jon

 

 

 

[88D]

4 minutes ago, The Great Bear said:

Some more coaches. Firstly a D88 brake third:

This print shows the end that is nearest to the build plate when printing. I haven't made an attempt to clean up the printing supports, but by reducing the size of tips of them they should with care clean up easier, with less damage to the detail at the end.

 

Next, some corridor celerestories, firstly an E73 composite:

 

This, unlike the photo of the E88, is the free end of the print, so no supports.

 

The chassis remain a pain to print, to avoid warping as mentioned above I print attached to stiffening beams then cure for a long time an hour plus and only then remove the supports. The downside is that the resulting print is very brittle - you can see where I snapped it in the photo. For the toplight frames I'm erring toward printing via 3rd party using SLS Nylon or HP Mutlijet fusion tech, they are then more robust. More on this later.

 

Some coaches like this one, the location of the bogie centres ends up rather messily fouling the seats, but who's going to see...

 

And finally for now, a completed coach a C17 all third

Most of the pictures of clerestories in Russell show them in all brown livery, which suits me - far less painting and lining to do. This one has a stab at some weathering too.

 

All the best

 

Jon

 

 

 

Gosh, they look good! How long does it take for a coach to print?

[jamespetts]

These look splendid. Are any of these (or the Toplights) on Shapeways yet?

 

Incidentally, are you sure that the photographs depict them as brown (1908-1912 and also the first world war austerity livery) rather than lake (1912-1922)?

[The Great Bear]

1 minute ago, 88D said:

Gosh, they look good! How long does it take for a coach to print?

Thank you. Depending on the resin and the printer settings between 10 and 16+ hours. That's printing at 100 micron layer thickness. The resin that does it faster is more expensive and I think gives better, more detailed/crisper results. I think, stilll testing, slowing the print down, the speed the build plate moves to see if it improves print quality and repeatability.

[The Great Bear]

9 minutes ago, The Great Bear said:

Thank you. Depending on the resin and the printer settings between 10 and 16+ hours. That's printing at 100 micron layer thickness. The resin that does it faster is more expensive and I think gives better, more detailed/crisper results. I think, stilll testing, slowing the print down, the speed the build plate moves to see if it improves print quality and repeatability.

 

That's for the body BTW. The body, interiror and chassis don't all fit in the build space so it takes two print runs to do a coach.

[The Great Bear]

1 hour ago, jamespetts said:

Incidentally, are you sure that the photographs depict them as brown (1908-1912 and also the first world war austerity livery) rather than lake (1912-1922)?

Yes, some of the photos have dates and locations and they have the twin cities crest rather than the garter crest and some where you can make out the text it is the 1942 or later sans-serif font

 

[88D]

Whose grab handles do you use on the coaches, please?

[Penrhos1920]

3 hours ago, jamespetts said:

These look splendid. Are any of these (or the Toplights) on Shapeways yet?

 

Incidentally, are you sure that the photographs depict them as brown (1908-1912 and also the first world war austerity livery) rather than lake (1912-1922)?

 

There aren’t many photos of the 1908 brown livery.  It’s fairly easy to check that the photo shows the 1930s or WWII brown liveries as the GWR roundal or twin shields is usually visible.  I think @The Great Bear has got it spot on, including just the right number of sheeted over panels.

Edited January 24, 2020 by Penrhos1920

[The Great Bear]

On 24/01/2020 at 17:04, jamespetts said:

These look splendid. Are any of these (or the Toplights) on Shapeways yet?

 

 

Thank you. I've gone back and had another look at Shapeways. Taking the E73 as an exampe, if the body is printed complete like I do on my own printer it comes in at £66 in Versatile Plastic or a whopping £127 in Fine Detail Plastic. For panelled coaches the sample prints near the start of this topic show that the Versatile Plastic simply isn't good eough.

 

I've had a play with the E73 and broken the body into parts:

The sides printed as above in Fine Detailed Plastic would be around £50. The roof printed in Fine Detailed Plastic would be around £29 which seems a lot; as there's less detail probably could get away with the Versatile Plastic which would be around £18. Altogether that's more sensible but still not cheap.

 

Would people want the coach interiror and chassis? This is where the costs start to mount.

 

The interior printed as whole in Versatile Plastic is £37! So I tried breaking into parts:

 

But, this doesn't save any money. Seems a lot to me.

 

The chassis would be around £18.

 

So we have:

Body sides £50

Roof £18

Interior £37

Chassis £18

Total £123

 

To that you would add another £30 or so for bogies, wheels and the commode handles.

 

It strikes me that it's the interior and to lesser extent chassis that seem bad value. I'm open to suggestions on this as to how this could be arranged to make more economic so my designs can be shared.

 

 

 

 

 

Edited January 26, 2020 by The Great Bear

[jamespetts]

My own preference would strongly be for the complete shell, one piece interior, etc., so that there is as little assembly to do afterwards as possible: this is, in my view, one of the strengths of 3d printing, in that the work is done once at design stage and then the mechanical process of assembly is largely automated.

 

I can understand, however, that others may prefer the budget option (there is a tradeoff between time and money in this case, about which different people may have different preferences). Perhaps you might offer both as alternatives, since doing so would only entail a very small amount of additional work in uploading and setting up the product settings?

 

Also, if your wall thicknesses are all >1mm, you might investigate using iMaterialise, which I am told has a better customer service than Shapeways, albeit its material tolerances are not as good in some cases.

Edited January 26, 2020 by jamespetts

[The Great Bear]

On 24/01/2020 at 19:43, 88D said:

Whose grab handles do you use on the coaches, please?

 

They are ones I designed and got printed in brass by Shapeways. They work at around £14 for 24 of them. Shapeways have a minimum price for casting stuff IIRC and having played around with various numbers of handles, this design ended up being the most economic.

 

The shape isn't quite right, the shape of the real things is very complex and hard to determine exactly -I haven't found any drawings. They are also a tad chunkier than they should be due to Shapeways minimum thickess requirements. I've set this to be publically available, since I've had some printed I think that should work? (I can't remember does Shapeways require you to make one for yourself before selling?)

 

(When fitting to the coach, I tend to find it a lot faster to snip off the bottom lug, so only one goes into the hole in the coach body, rather than fiddling trying to get two in, even if they should fit it ends up testing my patience too much!)

 

https://www.shapeways.com/product/B8C28QZDF/commode-handles-x24

 

 

Edited January 26, 2020 by The Great Bear

[Clearwater]

Hi Jon

 

Have you considered mixing media? Eg using a comet or worsley works brass chassis?  On wizard’s website, the comet UNderframe is £8.50.  Brass handles are about £3.50.  Great thread btw!

cheers

 

David

[5D_Stoke]

On 26/01/2020 at 15:56, The Great Bear said:

I can't remember does Shapeways require you to make one for yourself before selling?

No Shapeways doesn't require you to order a print before they will sell designs for you. Though it is useful to test designs esp if you want one yourself, or to run a test at home if you have your opwn printer.

I-materialise does demand you order one yourself first, and also has strict rules preventing the use of sprues, so every part has to be printed as a separate model. So although they do a beautiful 'Gray Resin' material with which I have had superb results, the cost of complex multi-part (even just body + underframe) models becomes unaffordable.

[Quarryscapes]

On 24/01/2020 at 16:52, The Great Bear said:

And finally for now, a completed coach a C17 all third

 

That is one flippin fabulous looking model 

[The Great Bear]

15 minutes ago, Quarryscapes said:

 

That is one flippin fabulous looking model 

 

Thank you. The wartime brown livery helps stop me ruining it with my dodgy painting and transfer application!

[The Great Bear]

I am slowly working my stash of printed coaches, finishing them. Here's something a bit different, a D88 brake third, which is an ex-ambulance stock Toplight refurbished in the early 1920s. So confusingly, it is a Toplight without toplights

 

 

I added some details not on previous coaches, luggage door grilles and the corridor handrail. The grilles (Brassmaster) look a bit heavy, as much a result of my over-application of paint.

 

 

.

[Welchester]

At first sight I thought the ventilators were a bit overscale, but then realised they're the posts of the lineside fencing.