S Scale in 3D - whats on the computer.

[Rosedale]

I'm currently climbing the foothills of the Eiger learning DesignSpark Mechanical, another free 3D CAD package available via RS Components. I have quite enjoyed the learning so far but I have a long way to go before I can get to the level of you guys! I was given some initial help on 'how to get started' from a fellow member of the Leeds Model Railway Society who has done some amazing work designing some complex buildings for the Derwent Valley Light Railway. Basically you draw a shape then extrude it. I think DSM Is a good package and there are lots of on-line tutorials and articles. 

 

The attached work in progress is a chassis for a NER S1 hopper wagon to match the brilliant hopper designed by Flubrush. The seperate piece is my first attempt at some strapping which I'll copy and attach to the solebars. I also need to draw crown plates etc and cut a 'fillet' from the inner solebar sides. 

 

My main enjoyment will always be getting a sheet of NS or plasticard or wood and fashioning a model.  But the possibilities of 3D, particularly for complex items that need to be mass produced is certainly there and I hope will become part of my 'toolkit'. My scratchbuilt S1 chassis has about 60 separate parts. If I can cut that down to say 10 and gain reliable consistency then its a result.

Onwards and up the Eiger  - ropes and crampons needed for the next stage...........!     

[Timber]

Rosedale this is great work.   My recomendation is that as you develop the artwork you start to test its geometric integrity by sending it so something like https://www.meshmixer.com/download.html.

 

I do not know how DSM works but when working in Fusion every few hours I stop, create a print and pass the print through Meshmixer.   If Meshmixer tells me I have a problem I can go back and double check the latest changes.  

 

The problem you want to avoid is non-manifold geometry.  It is not something that you need to understand but it is something that you need to avoid.  https://www.sculpteo.com/en/3d-learning-hub/create-3d-file/fix-non-manifold-geometry/.   Checking at regular intervals saves time in the long run.  Otherwise you will get to the end of building a complex model, find that you have poor geometry and have to start to try and debug the whole model rather than testing changes as you go along.

 

Tinkercad will not allow non-manifold geometry but in Fusion and Sketchup the application will allow you to do what you want - something that could include poor geometry.

 

There are tools that will fix poor geometry but i always find it is best to fix at source.

 

Keep up the great work!

Edited January 7, 2022 by Timber

[Rosedale]

Thanks Timber, that's great advice and I'll take a look. 

[Rob R]

A recent visit to a fellow S Scale modeller has highlighted a requirement for a number of 3' 6" (or 3' 7") wagon wheels with 8 open spokes for a future project.

There is nothing suitable in the 4mm ranges that can sensibly used so I thought I would have a go at printing some to suit the Society's 3'7" steel rim.

 

First draft in TC

It will need a bit of trial and error and quite a few test prints to get the od to suit the rim and the id to suit the axle allowing for shrinkage etc but that is the same with the loco driving wheels as well.

Will keep you posted.

Rob

[Rob R]

First post after the "break".

Having a few minute spare at work tonight I have reworked the 42" 8 split spoke wheel, to refine it and to fit the SSMRS rim now that I have some to measure.

 

v2 to the left, v1 to the right

 

Printing tomorrow (later today when I get up that is).

 

[Rosedale]

Looks great! I hope you'll be able to report back on next week's Zoom call?

[apl31]

While waiting for parts to get on with Furness Tank engine project. I thought I would finish a few old drawings I had started.

This is a LNWR D16 brake van. I'm going to order some W iron and wheels  then print it when Ive checked fit.

[Rob R]

2 hours ago, apl31 said:

While waiting for parts to get on with Furness Tank engine project. I thought I would finish a few old drawings I had started.

This is a LNWR D16 brake van. I'm going to order some W iron and wheels  then print it when Ive checked fit.

I know someone who needs a couple of them........

[apl31]

When I get  the underframe sorted I'll send you the file .

[apl31]

Rob,

You may be able to help with a question. Which of the society W iron etches would best suit this  I'm not sure what differences are . They are ~3 foot wheels.

[flubrush]

WI002 is for wooden underframe wagons with smaller bearings - basically most wagons up to the turn of the 19th/20th century

 

WI003 is for wooden underframe wagons with larger bearings - basically most wagons from the start of the twentieth century.

 

The main difference between these two "W" irons is the distance between the legs of the "W" irons.  Earlier  Victorian wagons had smaller bearings and the distance between the legs was around 6.5 inches.  The later,  heavier wagons had larger bearings and the distance between the legs was around 8 inches.

 

These "W" irons are designed to fit wooden framed wagons where the distance to the underside of the floor is about 4 feet above rail level.

 

WI004 is for steel underframe wagons with larger bearings, the main difference being that the floors on steel underframe wagons were about 3' 9" above rail level.

 

WIBR1 is a BR plate "W" iron for steel underframes.

 

For your LNWR brake van with a wooden underframe,  either WI002 or WI003 will suit - just measure the distance between the "W" iron legs on your plan to make the choice.

 

All the above are for 3' 1" wheels.

 

WI001 is for 3' 7" wheels on a wooden underframe with 4' to the underside of the floor.

 

Jim.

Edited April 22, 2022 by flubrush

[apl31]

Thanks Jim very helpful

[Rob R]

Jim beat me to it and quite rightly so, as the fact we have such a splended range of W irons is entirely due to him.

 

Rob

[Lacathedrale]

On 22/04/2022 at 19:34, flubrush said:

WI002 is for wooden underframe wagons with smaller bearings - basically most wagons up to the turn of the 19th/20th century

 

WI003 is for wooden underframe wagons with larger bearings - basically most wagons from the start of the twentieth century.

 

The main difference between these two "W" irons is the distance between the legs of the "W" irons.  Earlier  Victorian wagons had smaller bearings and the distance between the legs was around 6.5 inches.  The later,  heavier wagons had larger bearings and the distance between the legs was around 8 inches.

 

These "W" irons are designed to fit wooden framed wagons where the distance to the underside of the floor is about 4 feet above rail level.

 

WI004 is for steel underframe wagons with larger bearings, the main difference being that the floors on steel underframe wagons were about 3' 9" above rail level.

 

WIBR1 is a BR plate "W" iron for steel underframes.

 

For your LNWR brake van with a wooden underframe,  either WI002 or WI003 will suit - just measure the distance between the "W" iron legs on your plan to make the choice.

 

All the above are for 3' 1" wheels.

 

WI001 is for 3' 7" wheels on a wooden underframe with 4' to the underside of the floor.

 

Jim.

 

If only other societies and scales were this thorough with their information - all these measurements (i.e. height to underside of wagon) are wonderful to see provided! You'd think that other corners of the internet were charged by the word...

[flubrush]

On 22/04/2022 at 19:34, flubrush said:

WI002 is for wooden underframe wagons with smaller bearings - basically most wagons up to the turn of the 19th/20th century

 

WI003 is for wooden underframe wagons with larger bearings - basically most wagons from the start of the twentieth century.

 

The main difference between these two "W" irons is the distance between the legs of the "W" irons.  Earlier  Victorian wagons had smaller bearings and the distance between the legs was around 6.5 inches.  The later,  heavier wagons had larger bearings and the distance between the legs was around 8 inches.

 

 

 

I've just been doing a bit of work on another set of "W" irons and I realised that I had quoted the wrong dimension for the width between the legs on the "W" irons for larger bearings.  It should be around 9.5",  not the 8" I stated.   I suspect I was probably thinking about the actual bearing diameter at the time.

 

Jim.

[Rob R]

I was just watching through the youtube of the last SSMRS Zoom call and someone (Jim?) commented on having to completely redo the supports to a print model when making even a minor modification.

If you are using Chitubox you can save a "Project" at any time, I usually do it just after slicing and saving as a .ctb file for printing. The "project" is saved as a .chitubox file and you can open it and carry on editing the supports from where you left off and then save as a "project" again, under a new file name if required, and also save as a .ctb for printing.

You can do the same in Lychee, they call it a "scene" but it works pretty much the same way.

 

Rob

[flubrush]

4 hours ago, Rob R said:

I was just watching through the youtube of the last SSMRS Zoom call and someone (Jim?) commented on having to completely redo the supports to a print model when making even a minor modification.

 

Rob,

 

I was referring to making small changes to the original .stl file when you need to load the altered file into Chitubox and start all over again with the supports. :-)

 

Jim.

[MikeTrice]

My workflow after adding supports in Chitubox is to save the file and supports as an stl file. I have been known, on occassion, to load the supported stl file into blender, select the original model and delete it then import the revised model and orientate accordingly against the supports then re-export as stl, slice and print.

[Rob R]

Spalding and Bourne Railway Gloster van of 1868.

For an SSMRS member but in 3 scales, S, 7mm and G3

G3 version tacked together with more detailing bits to add.

Rob

[apl31]

Very nice Rob.

What are you planning for roof? Every time I've tried to print a separate curved roof  for wagons and FR 2-4-2T they  warp (tending to turn inside out ) despite adding extra thickness and bracing. That is why I designed the LNWR van with integral roof and access from below.

I spent a lot of time adding that compound chamfer on frame edges but it didn't show when printed , hopefully you will have better luck

Aidan

[Rob R]

Aidan,

No floor and no roof.

There are far better materials for floors and roofs than printed resin and it saves a load of printing hassle.

The S version will be printed complete sides/end/solebars with a suitable ledge on the inside to mount the floor.

The G3 version will be in 6 pieces - ends/ part side in a u shape x 2, 2 doors and 2 solebars (if they fit the printer) all assembled around a 3mm ply floor.

The 7mm will hopefully fit the build plate in one piece like the S version, if not I will have to break it down like the G3.

The chamfer may not show in S but you might notice if it's not there if you see what I mean? It will certainly show in the larger scales.

Rob

 

[apl31]

Yes I put some 1mm thick brass floor in it adds weight and is good fixing for the W irons. Originally I had a 2 piece floor as I had a central beam as a precaution against  solebars splaying. With new version I may cut the beam out (after printing) before fitting 1 piece floor.

[Rob R]

Just started a crash course in Fusion 360 this week. A workmate I am on shift with this week is quite proficient at Fusion so in the quieter moments I have been playing,

 

 Dome for a Londonderry and Lough Swilly Sharp Stewart 0-6-0t (5ft 3in gauge) for a possible excursion to the Emerald Isle.

Drawn at 1/32 with much use of the "undo" button. 🙂

 

Rob

[Rob R]

Safety Valve cover to match.

Time for a work break now....

[flubrush]

9 hours ago, Rob R said:

Just started a crash course in Fusion 360 this week. A workmate I am on shift with this week is quite proficient at Fusion so in the quieter moments I have been playing,

 

 Dome for a Londonderry and Lough Swilly Sharp Stewart 0-6-0t (5ft 3in gauge) for a possible excursion to the Emerald Isle.

Drawn at 1/32 with much use of the "undo" button. 🙂

 

Rob

 

Good when something comes together in 3D CAD. :-)    I spent yesterday trying to draw a reverse curve in a sketch in Solid Edge - something I would do in seconds,  almost without thinking,  in 2D CAD.  I spent hours trawling though Googled pages until I hit on the method to use almost by accident.  I then remembered that I had learned about it a year ago when starting in Solid Edge. :-)  So a day when I had hoped to do some more prints "went out the window".  But at least I know for the next time - if I remember. :-)

 

Jim.