MR Brake van 3D print

[woko]

Hello

 

I am new to this site and am looking to get into 3D printing, mostly because I have over 20yrs of professional experience in 3D modelling and a big interest in Model Railways. I'm keen to get started, and to kick off I thought I would model the MR brake, mostly because my dad has always wanted one, and besides the kits, they have never gotten round to making a 4mm version in ready to run.

 

So I wanted to ask you knowledgeable folks on here if I had made any glaring errors and would be keen to get your thoughts. Please ignore the wheels as I intend to purchase wheels to place in the model and these are only for illustrations purposes hence why they are missing the axle.

 

Out of interest this took around 6hrs to model in 3D for both versions, and I intend to break up the model into 4 components for printing, the roof, the main body, and then both sides of underframe/carriage so I can place the wheels in once I have the sizing correct, and add weight to the interior of the brake if needed.

I acquired the drawings online, they were basic, but had the right scaling, the details I have gathered from photographs.

 

Many thanks and would appreciate any feedback you care to give me, as I want to get this as accurate as possible.

And equally if this turns out fairly successful then I would like to have a go at making some more pre-grouping rolling stock

 

 

[Spitfire2865]

Id consider altering it to add a version without the number tile slides.

But it looks good. Id consider buying one of the 4 wheeled ones if you make them available.

[woko]

Thanks for the kind words Trevor, yes course if this comes out ok I can make all sorts of amendments, like droping the number tile slides. Im looking into purchasing a 3d printer in the next month or so to try this out for myself, and hope to post the results on here for feedback.

[Paul Cram]

You will need to think about how you arrange access to the interior for glazing purposes.

[t-b-g]

You will need to think about how you arrange access to the interior for glazing purposes.

 

Should be OK with that if the roof is a separate part as per the O.P.

[swampy]

Yes, I would remove the tablet racks, it's an easy job to add a few pieces of plastic strip. It depends on what period your dad models.

 

Would not the inverted U rail on the platform be rather flimsy if 3D printed?

 

The number area on the body was painted, not a cast plate(?) as you have shown.

 

You could include a slot for the glazing like the glazing, like this...

 

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HTH

 

Pete

[Spitfire2865]

Would not the inverted U rail on the platform be rather flimsy if 3D printed?

 

Pete

Yes, the handrails should be wire, not printed.

Though Im assuming this 3D model is more of a basic proof of concept.

The handrail locations should have a small indented pip to center a drill in.

 

Also, what means of suspension are you considering? I think this design would suit sprung w irons as the axleboxes are snug against the footboards.

[Poor Old Bruce]

The number area on the body was painted, not a cast plate(?) as you have shown.

 

Agree.

 

Spitfire also mentions spring suspension. I assume he means on the model but the full size things had differing spring hangers, some with links and others with 'J' hangers and at least two different sizes of rubber auxiliary springs.

[sharris]

Yes, the handrails should be wire, not printed...

 

 

While I'm at work and about 5 miles away from my copy of Essery's book so I can't say for certain, the general consensus from Google Images indicates that for MR livery, the M and R go through the upper side handrails - making the rails from wire and fitting them afterwards would make applying transfers much easier. 

[Guy Rixon]

The vans look nice, but I haven't compared them to any drawings or photos. I have a few points of detail.

 

The inboard spring shackles on the 4-wheeled van seem not to connect to anything; in the render, I can see white space around the end of the shackles. I presume that they are supposed to connect to the curved castings that show below the solebars.

 

You've shown the area where the number goes as a framed board mounted on the side of the van. Are you sure that this is right? I thought that the surround for the number was just a painted area. There are preserved vehicles like that.

 

The SE&CR had six-wheeled vans that were basically the Midland design with different buffers and axleboxes. These didn't have the tablet racks and didn't have their numbers on separate boards.

 

I would suggest that the solebars be spaced to allow brass axleguards to fit, so that the vans can be sprung or compensated. This might mean that the solebars need to be thinner than scale.

 

Some modellers like to fit sprung buffers, and many like their buffers to have metal heads for strength. You might consider printing the buffers headless, with a bore for the ram. You could either print with the 1.0mm/0.5mm concentric bores for MJT/Gibson/Maygib spring parts (I can help with exact dimensions if you wish; I've printed many buffers like this) or just with a 1.0mm through hole and those who want springing can put bushes behind the headstocks.

 

Finally, are these prints to be in FUD or WSF?

[woko]

Thanks guys this is great stuff much appreciated

 

Yes the number plate is painted and not cast you are correct, I wondered if I printed this then it would be easier to paint? However incorrect, do you know if transfers are available for this?

 

Guy, Spitfire and Bruce all mention the axles, this is where I will throw my hands up and admit I am a little in the dark about this area as I don't seem to have enough visual information to fully complete this properly so any guidance or assistance here would be truly appreciated

 

Swampy my Dad prefers pre-grouping era so this will be in MR, and depending on how well this goes I hope to do a bunch more stock for him ranging across MR, LB&SC, LSWR, LNWR, GNR, GCR and SE&CR, L&YR.

 

I'm at work at the moment but will make some amendments tonight and maybe do an exploded render showing how this thing goes together and it will hopefully highlight all the errors. I also have a quick Midland Weighbridge hut I have modeled to test to see how well the printer will do printing brickwork.

 

 

 

 

 Guy sounds like you have a bit of experience 3D printing? Do you own your own printer or send your stuff out to be printed? What would you recommend? I'm not getting the 3D printer for a couple of weeks I'm still in the researching phase, but I would hope it could print the handrails, from some of the detail I have seen on the Zortrax M200 it comes very close and the printing material is PLA or ABS, though they might be a bit brittle and if this is not good enough for the fine details then I will have to provide pre-drilled holes for the wires to be inserted in. I can also imagine this will take a few attempts print wise to get completely correct.

 

[sharris]

...Yes the number plate is painted and not cast you are correct, I wondered if I printed this then it would be easier to paint? However incorrect, do you know if transfers are available for this?...

 

 

The old PC Models transfers had an LMS wagon transfer set (I believe this same set is now printed by the HMRS) which includes the panel for brake van numbers.

 

There is a preserved 6-wheeler at Butterley which from this page https://antstrainphotos.smugmug.com/Midland-Railway-Centre shows that the vertical planking still visibly runs continuously through the number panel.

[Steamport Southport]

The HMRS also produce a set called LMS English Pre Grouping Goods Vehicle Insignia which has the Midland Railway version with the M on it. Sheet Number 17.

 

Slaters used to provide the transfers for the Midland and LMS eras as a separate item. With the current difficulties with Coopercraft then I doubt they are still available. Although unused sets do come up on Ebay quite often.

 

 

Jason

[croydon junction]

if they were in use into the late 1960's/early 1970's I might be interested

[woko]

 

 

Evening folks I really appreciated all the advice and knowledge shared, so have made some quick adjustments to the smaller Brake Van, I have attached the springs either ends using the images on the site link Sharris sent as a reference, which was extremely handy, so many thanks and much appreciated and of course any links to wagon drawings would also be much appreciated as I can't wait to knock up some more stuff as I will have a couple of weeks before finally getting this printer.

 

I have also removed the cast number plate, and tablet racks as suggested, and shown how I am going to split the model to print for the first run, this may require further splitting, and of course the removal of the handrails for wire.

I am going to print the buffers, but could look into a version with no buffers to allow metal buffers to be fixed as suggested by Guy.

 

 

 

 

 

 

 

[Steamport Southport]

Matthew.

 

 

Not in mainline use.

 

I haven't got my Midland Wagons books at hand, but I don't think many would have lasted past 1948. Those that did were probably only in Departmental use. They were quite antiquated even in 1923 especially with them having a wooden underframe and only rated at 10 tons (15 tons for the six wheelers). The LMS built quite a lot of modern 20 ton brake vans in the 1920s and 1930s.

 

I believe that a quite a few of them were sold and survived in industrial / MOD / NCB / Wemyss Private Railway use into the 1960s though.

 

 

Jason

[Guy Rixon]

 Guy sounds like you have a bit of experience 3D printing? Do you own your own printer or send your stuff out to be printed? What would you recommend? I'm not getting the 3D printer for a couple of weeks I'm still in the researching phase, but I would hope it could print the handrails, from some of the detail I have seen on the Zortrax M200 it comes very close and the printing material is PLA or ABS, though they might be a bit brittle and if this is not good enough for the fine details then I will have to provide pre-drilled holes for the wires to be inserted in. I can also imagine this will take a few attempts print wise to get completely correct.

 

 

All the prints I have obtained are done by Shapeways in Frosted Ultra Detail. That's their second best material for showing fine detail; Frosted Extreme detail shows slightly smaller features but is more expensive. Both these are UV-cured resins rather than thermo-softening plastics like PLA and ABS. Shapeways' White Strong and Flexible material is, IIUC, their nearest to the PLA used in domestic printers.

 

Personally, I think that that WSF prints are inadequate for detailed, cosmetic surfaces. All the pictures of WSF prints I've seen look too coarse for 4mm scale work. This suggests that a home PLA printer is not going to do full justice to your designs, although it will be great for prototyping.

 

Others tell me that Shapeways are not the absolute best printers for quality or price, but their on-line operation is very convenient, so I stick with them. Modelu are another firm that has been recommended to me.

[sharris]

Now that I've checked Essery, I can confirm that MR liveried vehicles had the M and R behind the upper handrail, with the rail more-or-less bisecting the letters. LMS liveried vans had the letters just above the upper handrail, so removable rails would benefit MR modellers applying lettering.

 

In terms of buffers the 6 wheeler (D393/D394 - the former is 15 ton, the latter 20, but externally similar) appear to have differing buffer types.

 

It would also be possible to use the 6 wheeler as the basis for D1045 - basically take out the centre wheels and move the inner footboard supports a bit more towards the centre.

[woko]

Guy you are of course quite right in saying the resin printers provide the best resolution, however im currently thinking of getting the zortrax m200 which has had some strong feedback from the modeling community, especially in character/figure modeling, its reasonsbly priced, but there is an amount of clean up afterwards, and soaking the model in acetone to remove any banding that occurs with pla printers. But more so im keen to see how the Bcn3d sigma fairs in tests, its print resolution potentially delivers higher than the form one plus, resin printer so will wait and see.

 

Thanks Sharris yes I noticed the different buffers to, and have modeled those hopefully according to the correct versions, and your correct it would be super easy to modify this model to any variation, or equally borrow parts for other future 3d model wagons. So its handrails removed, and then attached with wire latterly.

[eldavo]

Nice CAD models there. I don't want to quell your enthusiasm but from my experience you will struggle to get a decent quality print with your current component set on a FFF printer. I would suggest you split the bodywork into sides and ends and print them inside face down on the printer bed. Trying to print the complete body shell will give you a fragile structure with poor surface quality on most printers.

 

I would not even attempt to print the curved roof. You will have distinct ridging in the print if it is printed with the interior face downwards and any other orientation will require substantial support material which will be a pain to remove. Use a bit of plain old plasticard.

 

Bear in mind you cannot smooth PLA with acetone or indeed any other chemical you would want to get within 20 yards of! You can chemically smooth ABS but it is trickier to print with.

 

Cheers

Dave

[Poor Old Bruce]

if they were in use into the late 1960's/early 1970's I might be interested

 

There was a six-wheeler within the C&W Works at Derby in 1966 or 67 but I dont think it had moved for some time. Oh for a digital pocket camera in those days.

[Guy Rixon]

Woko, I don't want to put you off getting a PLA printer and I really hope that it works out for you. I suspect that it will do quite well at printing complex detail - which would be why the figure modellers like it - but poorly at making flat surfaces properly flat and smooth.

 

The outstanding problem with WSF prints of vehicles is that the should-be-smooth surfaces come out with coarse texture that is hard or impossible to fill or polish out.

[woko]

Eldavo and Guy thanks I understand that PLA and ABS is not as superior as Resin, especially the Form one plus which is currently the desktop market leader, but coming in at nearly 3k its a big investment, however the Zortrax and BCN3D are moving it up a gear, some of this work has had post process, in terms of sanding but I thought it might be of interest to see the differences between the current 3D PLA printers, and the Zortrax whilst not perfect yet, its getting much better

 

So here are a few things printed on the Zortrax

 

 

This is a comparison with other PLA - ABS printers, not perfect but a big improvement I think you will agree

 

 

And then these have had post work on the models to obtain the smoothness when required, so it is possible, depending like you say Eldavo on the filament you use

 

 

 

I currently don't have any prints on the BCN3D Sigma, but I am hearing good things, infact it has a better resolution and print quality apparently than the form One Plus resin printer, but I am waiting a couple of weeks until that can be fully tested and clarified for me by Dream 3D in Portsmouth

 

 

 

I'm not only going to use this to make model railways I also want it to proof out some ideas I have for some toys and models, that I hope to design and build. I also think its time I started to look into this 3D printing, being involved in a daily basis with building 3D models it seems a natural progression, and lets face it, its only going to get better and cheaper in the long run.

 

Anyway be good to get your thoughts

 

[woko]

Oh PS I should mention I have not physically printed these items, just what my research has so far shown possible on this printer

[Guy Rixon]

The tank print is commendably smooth in the flat areas. Has it been smoothed after printing? And what's the scale?