SimonD’s workbench

[simond]

I'm not sure how much of the distortion is real, and how much an artefact of extreme close-up using the iPad, but either way, it’ll look just fine on the solebar of the Mink F. It is 0.4mm thick around the rim, and only 0.2 between the figures.

And yes, the G.W. is not the correct font

 

[adrian]

I'm not sure how much of the distortion is real, and how much an artefact of extreme close-up using the iPad, but either way, it’ll look just fine on the solebar of the Mink F. It is 0.4mm thick around the rim, and only 0.2 between the figures.

I take it that is off the 3D printer? Very impressive - I might have to look at printing a few plates for MR tender plates, volumes, scoop etc.

 

[simond]

Thanks Adrian,

Yes. I was really quite surprised & delighted.

I thought, “I’ll not know if I don’t try”, and as the data was available, and the drawing time was minimal, I threw it on the last print run. I printed it with a long edge horizontal, and the short edge at 45 degrees to the build plate, characters towards the resin, of course. Five supports, one in each corner, and one somewhere in the middle, but nearer the build plate.

difficult to paint though…

 

[simond]

Wagons…. Mica A’s to be precise. I’m a Birkenhead lad (though live is sight of France nowadays) and built a Finney 47 some twenty years back. It still needs a train of meat wagons, though I’ve only got three & a kit, and four wagons an express meat train does not make…

now thirty would be good, but twenty‘s plenty. The prices of the WEP and Peco/Parkside kits is north of 35 quid, and say sixteen of them would be over five hundred pounds, even allowing for a bulk discount. And they’re not sprung, and who wants to build 16 identical kits anyway.

I have a laser, and I have a 3D printer, and I have access to a high quality printer, and I’m old enough to remember Peco Wonderful Wagons.

I’ve already printed a sprung functional wagon chassis, which works well. The design needed lengthening, and cosmetic solebars adding, and I think we can tick that one off, not quite finished but nearly there. Test print tonight maybe.


Bodies from MDF. Check.


Printed overlays - easy. Cutting out & engraving them reliably with the laser, maintaining registration, might be more difficult. Roof, nearly but not quite. Overlays not yet done, but laser or 3DP, easy.



Wheels & bearings - Slaters
3-links - Premier
Buffers - looking at turning these from bar
Transfers - none, print overlays with different numbers & varying Tare weights. Need to work on the letter form to match the font that was used. Might even make each wagon a different number on each side!

Estimated wagon cost will be IRO £18 depending on how successful I am with the buffers.

A useful saving, and an interesting project, that’ll keep me busy a while yet, I reckon.

if anyone has any photos of “The Meat” daily Birkenhead to Smithfield via Padd, I’d love to see them. I’m also interested to know what guards van was used.

atb
Simon

 

[Phil O]

Simon,

Didn't Micas use DC brakes? I think it was either DC 2 or 3.

 

[simond]

Thanks Phil,

I believe that the 17’6” Mica A’s used the RCH chassis, with the W irons spaced for 10’ WB. There’s an example on the Didcot society’s website which I have copied here for reference - this is of course a TEVAN, but it’s only a repaint of a Mica A (with the ice cabinets removed.)

Tuesday Treasures - September 2020 | Didcot Railway Centre. Their copyright assumed.




I’m glad I gound that, it’s a cracking detail picture!

The X8 Mica B’s did have DC brakes, but it appears that some of them had conventional lever brakes too, on a quick Google image search. Not sure whether these were a later conversion, or as built.

All Micas were vac braked for express running - I need to add the tie rod, but I doubt it’ll print.

Currently fighting with brake levers, and the guide-ratchet thing. I remember some months back @Bill Bedford made a comment about “more time designing than making”, I’m rapidly finding out that he’s spot on! Minor adjustment of modelling, do a bit of CAD each evening, and when it’s done, it’s done. It’s not a race, as Chris Klein once remarked.

atb
Simon

 

[michael mott]

Minor adjustment of modelling, do a bit of CAD each evening, and when it’s done, it’s done. It’s not a race, as Chris Klein once remarked.

Totally agree. It applies to the hobby in general also in my view.
Michael

 

[simond]

well, between going to the tip and watching a memorable Italy - France rugby match (it was close, it would have been the upset of the Nations tournament for the traditional underdogs to beat the current holders) I have done a bit more.



3D wise, I need to add the short T-stanchions on the buffer beam, and put the holes in for the lamp iron (or leave a slot and put a representation of the rivetted flange so I can use a bit of bent brass) add label clips and wagon plates, and a few other extraneous bits on the solebars, and generate some vac pipes. The brake handle this side needs to be finished, and then not-mirrored for the one with a cam, and I haven't yet drawn the steps which will be push-fit in slots in the van body. I think the side steps will have to be brass. Better add some holes for them too.

I need to give the roofs some more thought, and print some body overlays so I can try to etch the plank lines in registration. That'll be a challenge, I think.

anyway, enough for today.

 

[Pete_S]

Thanks Phil,

I believe that the 17’6” Mica A’s used the RCH chassis, with the W irons spaced for 10’ WB. There’s an example on the Didcot society’s website which I have copied here for reference - this is of course a TEVAN, but it’s only a repaint of a Mica A (with the ice cabinets removed.)

Tuesday Treasures - September 2020 | Didcot Railway Centre. Their copyright assumed.


View attachment 179683

I’m glad I gound that, it’s a cracking detail picture!

The X8 Mica B’s did have DC brakes, but it appears that some of them had conventional lever brakes too, on a quick Google image search. Not sure whether these were a later conversion, or as built.

All Micas were vac braked for express running - I need to add the tie rod, but I doubt it’ll print.

Currently fighting with brake levers, and the guide-ratchet thing. I remember some months back @Bill Bedford made a comment about “more time designing than making”, I’m rapidly finding out that he’s spot on! Minor adjustment of modelling, do a bit of CAD each evening, and when it’s done, it’s done. It’s not a race, as Chris Klein once remarked.

atb
Simon

That photo also appears in Russell's Wagons Appendix, (Fig. 206, p. 127) & along with Figs 207 (V.31 ex-X.2) & 204 (X.2) challenges the view that the chassis were painted black.
The vac pipe & wheels of 105804 are definitely a different, darker shade than the chassis. Vac pipes were black or red according to the GWR 1936 Rule Book Appendix:—



So, White body, Grey chassis, Black Wheels?

Pete S.

 

[simond]

OK, I think I have completed the CAD. I have some reservations about printing but before I slice the bits, can anyone see anything wrong/missing/stupid???

The brass-coloured bits (horse hook, safety loops, lamp irons) will be brass, and the steel coloured bits (buffers, wheels, couplings) will be steel, apart from the guitar string springs, the rest is 3DP


comments & suggestions very welcome

TIA
Simon

 

[Rob R]

Can't see anything obvious (brakes right way round etc).
Are you going to change the number on the plates for each print?
Go for it, and hopefully the bin monster will have to go hungry.

 

[simond]

Thanks Rob,

I suspect the number plates will not be modified to match the painted numbers.

I’d have to re slice the solebars for each wagon, as I designed them integrally. I guess I could do them separate…

let’s see how batch 1 goes!


cheers
Simon

 

[Big Train James]

Simon,
If you do choose to modify the plates on each wagon, you may be able to take advantage of a function in Chitubox Pro (at least, not sure if basic does it too) where you can replace the model portion of a supported project 1 for 1. This only works for models where changes are very minor, I believe something like the number plates would be a good example. Another example might include something like driver centers for steam locos, where the only significant change between them is the counterweight size. At any rate, the function is called "replace model" in Chitubox, and can be found by right clicking over a selected model. You will only see this menu if you right click over the model. If you right click elsewhere on the screen, you will see a different context menu.


I haven't messed around with it much yet, so I can't fully warn of whatever quirks may be encountered. I can say that the incoming replacement stl must already match the orientation of the model in Chitubox, or it won't match the original. I really need to get it dialed in because I'm going to be printing driver centers soon and it will save a lot of time with the supports.

Lychee has the same functionality, again I don't know if it's supported in both the pro and basic versions. I will say that the video I watched regarding the Lychee version suggested it was more robustly developed than the Chitubox version, which is about par for the course and to be expected. For one thing, it appeared that Lychee would re-orient the incoming stl to match the existing one.

By the way, the same technique would apply whether you changed each full car file or instead made the plates as add-on items. That would seem to make more sense to me. Changing one or two numbers per iteration and then replacing the model would save quite a bit of time on the support process.

This all may be a moot point depending on which slicer and version you are using, but it also might be something that's available that could save you time if you decide to go full rogue dysfunctional and change the number plates on each car. I know what I would do in this instance!

Jim

 

[SimonT]

Depending on your CAD package, you should find Export With Origin command will help with the Replace functon in Chitu/chee. It works in my Rhino/Preform world and has worked with contractors with machines that are above our pay grade.
Simon

 

[J_F_S]

... Another example might include something like driver centers for steam locos, ...

Jim, are you describing this driving wheel project anywhere? It looks very interesting - not least as I am about to start on something very similar. I am looking to build the wheel directly off the build plate as breaking a 4mm scale wheel off supports does not appeal!

(With apologies to Simon for stealing space on his workbench)

Many thanks
Howard

 

[simond]

Howard

No apology necessary!

 

[simond]

I ran the printer yesterday evening, the various steps to get to a printable file are outlined on @Kev T ’s thread as it included finding and removing islands. I couldn’t spend any time on the bits this morning, apart from cleaning the printer and the prints, and leaving them in the uv box when I went to work.

mixed fortunes, I think. I suspect I’ll be able to make a chassis from the bits, but it’ll be something of a learning experience. I’m going to have to revise the supports on most of the bits.

First, the successes, the vac cylinder and the axleboxes are pretty much spot on, I think.






The main chassis part, with W irons fitted ain’t bad, but has some distortion that I need to address, and I’m delighted by the lightness of the Morton brake levers and cams. The guides, however, won’t do, and the levers have a meniscus effect between the witness marks for the supports. These suggest to me that maybe an increased temperature of resin and air might reduce the resin viscosity and thus reduce this. Might end up searching for lizard heaters…




Brake gear is pretty good too. Haven’t yet tried to fit it to the chassis. Again, there’s the meniscus effect, particularly on the backs of the push rods. Perhaps I’ll flip them so the underneath of this is nearer the build plate so the meniscus can only be seen if you pick it up. Then again, you’re going to need the x-ray vision to see it as it is in normal circumstances. It would be good to fix, though.



Vacuum hoses. 2” pipe looks too undernourished. I might also exaggerate the ribbing which looks great on the CAD but is difficult to see on the printed parts. I wonder if one’s eye becomes somehow accustomed to overscale details?



And finally, the elephants in the room. The detail’s nice but no damn use if the chassis is not straight, flat and square.



So, progress, but still some way to go.


cheers
Simon

 

[Rob R]

Simon,
I found your Chitubox screenshot on the other thread (eventually).

I think you need to add (a lot) more supports at the bottom edges, fine or medium will do, just to support the first few layers of printing (your meniscus effect), otherwise they just flop about aimlessly until there are enough layers printed to stabilize it or it breaks off and floats away.

Same with the horizontals on the brake gear, more, lightweight supports.

You have the supports on the solebars at about 5mm spacing, stick 2 or 3 light supports in the gaps, it will look a lot better.

In fact, I would be tempted to put the solebars flat on their backs , possibly at 5 or 10 degrees lengthways, possibly the same with the floor unit with plenty of supports underneath (mix of heavy to to the work and medium/light to get the surface something like) as it is for a van and you wont see the top. The W irons will print fine vertically.

It is all looking not too far off, just a few minor tweaks and you'll be there.
Rob

 

[simond]

Thanks Rob

It’s looking feasible, certainly



I’ll have time to look at the supports and slicing tomorrow evening.

Link to Kev’s thread 'First 3D print’
First 3D print

Thanks for the suggestions re supports etc.
Simon

 

[Osgood]

.......
Vacuum hoses. 2” pipe looks too undernourished. I might also exaggerate the ribbing which looks great on the CAD but is difficult to see on the printed parts. I wonder if one’s eye becomes somehow accustomed to overscale details?
....

What O.D. did you draw it?

It's pretty chunky stuff.
If it helps here is a sectional drawing of a hose to a BR spec - dimension C fits the steel pipe O.D. of 2 5/16", you should be able to scale off the drawing to get a realistic dimension for the hose O.D.

EDIT: Caution - there's some distortion in the drawing so it looks chunkier than it really is!