Jump to content
JohnBS

Saint class locomotive

Recommended Posts

Hi all,

Below are some screenshots of renderings of a Saint class locomotive superstructure for 3D printing. The print file has been produced by my son, using Solidworks software.

The model is to 2mm scale and should accept either N-gauge or FS wheels. The layout assumes a tender-mounted motor with wire cardan shaft drive and two-stage reduction gear train in the firebox, driving the centre axle. Chassis will be split frame and details not included in the print (boiler fittings, handrails, rear steps, buffers, motion, etc) are to  be added in metal.

I intend to go for a trial print (Shapeways, FUD) in the next few days so I would be grateful for early comments and suggestions.

 

 

post-18048-0-24549100-1360107665.jpg

View from front

post-18048-0-79152100-1360107618.jpg

View from rear

post-18048-0-48014000-1360107689.jpg

Underside, showing separate backplate

Look forward to hearing from you.

John

  • Like 13

Share this post


Link to post
Share on other sites

Are you intending to produce the chassis in the same way?

Share this post


Link to post
Share on other sites

That model looks really good John, Im looking forward to seeing what shapeways make of it.

 

The only comment I have regarding it though is that I have had trouble in the past attaching bits with sprues, it (according to Shapeways) meant I was trapping the wax support material and made the finish very poor. You can at Shapeways add the removable bits 'floating' in the model instead of being physically attached. As long as they are in the same file then Shapeways classes that as a single part.

 

I hope that makes sense?

 

Missy :)

 

P.S. What are the chances of getting the file for the boiler? :P

Share this post


Link to post
Share on other sites

John

 

the 3D model you son has created looks great but don't expect to get a 3D print from shapeways that is the same standard as the 3D model, it will be close but it may need some careful fetling bring it up to a good standard.

 

I wish you well and hope it all works out for you.

 

Pete

Share this post


Link to post
Share on other sites
Are you intending to produce the chassis in the same way?
No, I will be making a conventional 2mm SA split-frame chassis out of 20 thou hard brass or nickel silver. I have sketched out the basic form in 2D CAD.John

 

That model looks really good John, Im looking forward to seeing what shapeways make of it. The only comment I have regarding it though is that I have had trouble in the past attaching bits with sprues, it (according to Shapeways) meant I was trapping the wax support material and made the finish very poor. You can at Shapeways add the removable bits 'floating' in the model instead of being physically attached. As long as they are in the same file then Shapeways classes that as a single part. I hope that makes sense? Missy :) P.S. What are the chances of getting the file for the boiler? :P

Share this post


Link to post
Share on other sites
That model looks really good John, Im looking forward to seeing what shapeways make of it.

 

The only comment I have regarding it though is that I have had trouble in the past attaching bits with sprues, it (according to Shapeways) meant I was trapping the wax support material and made the finish very poor. You can at Shapeways add the removable bits 'floating' in the model instead of being physically attached. As long as they are in the same file then Shapeways classes that as a single part.

 

I hope that makes sense?

 

Missy :)

Thanks greatly for your comments. I was also very concerned about burying the backplate in the firebox so I will pass the information on about Shapeways accepting loose bits in the same file - this would be very helpful.

 

P.S. What are the chances of getting the file for the boiler? :P

Yes, I'm sure the boiler can be abstracted. Let me know how much you want (smokebox and/or firebox as well?

John

Share this post


Link to post
Share on other sites

Looks nice, I would prefer an etched cab, but I assume that is something that could easily be done using 3D printing as an option.

 

Can your son also produce the fake euros as illustrated,. I can see a big market for them :-)

 

Chris

  • Like 2

Share this post


Link to post
Share on other sites
Looks nice, I would prefer an etched cab, but I assume that is something that could easily be done using 3D printing as an option.

 

Can your son also produce the fake euros as illustrated,. I can see a big market for them :-)

 

Chris

Chris,

Let's see what the cab comes out like.

I think that the Euros are available, currently at a cost of 1GBP each.

John

  • Like 1

Share this post


Link to post
Share on other sites

One suggestion, should you perhaps leave a little of the boiler bottom off where the  middle axle is, as I assume this will be the driven one. Or perhaps you have already a gear arrangement in mind for which sufficient clearance has been left?

 

I already have etch artwork for the coupling rods on a Saint/Star drawn from the official works drawings if that is of any interest.

 

Chris

Share this post


Link to post
Share on other sites
One suggestion, should you perhaps leave a little of the boiler bottom off where the  middle axle is, as I assume this will be the driven one. Or perhaps you have already a gear arrangement in mind for which sufficient clearance has been left?

 

I already have etch artwork for the coupling rods on a Saint/Star drawn from the official works drawings if that is of any interest.

 

Chris

Chris,

Thanks for the suggestion. The chassis layout that I've come up with doesn't need a hole in the boiler, although the bottom front of the firebox may need to have a notch in it to clear the gear train. However, I am not sure how I am going to get weight into the boiler without a hole, unless I use lead shot, and I am unsure how to retain that (not PVA as it can give rise to expansion and I don't know the long term stability of solvent or resin adhesives and the printing plastic).

I would be interested in the coupling rods, were it not for the fact that I have had to tweak the driving wheel centres slightly to avoid clashing flanges on the first and second axles. Have you got artwork or etches for connecting rods/crossheads/sidebars?

John

 

Share this post


Link to post
Share on other sites

Very wise to keep boiler band detail, etc. off the model, as it will make cleaning up and painting much easier.

 

Tim

 

Share this post


Link to post
Share on other sites

Possibly the best looking loco of all time.

 

Comments (well, you did ask)...

 

I can't see any guide holes or dimples for locating the slidebars or piston rod in that blank space at the back end of the piston. You might add something to the CAD to make like easier for yourself here. Likewise any other twiddly bits (lamp brackets on the footplate front?)

 

Should the back end of the valve chest stick out a bit further?

 

Any reason why no footsteps? - is FUD not up to doing these?

 

Can I join the queue for a copy of the boiler please?

 

Regards, Andy

Share this post


Link to post
Share on other sites
Better make sure that the cylinders don't foul bogie, or vice versa.

Thanks, good advice. I anticipate a bit of work with a Dremel will be necessary but I don't want to take off more than necessary so will leave that for fettling once the chassis is made.

John

Share this post


Link to post
Share on other sites

You could print the footsteps but they would also break off easily if you made them the thickness you wanted.

Share this post


Link to post
Share on other sites
Possibly the best looking loco of all time.

 

Comments (well, you did ask)...

 

I can't see any guide holes or dimples for locating the slidebars or piston rod in that blank space at the back end of the piston. You might add something to the CAD to make like easier for yourself here. Likewise any other twiddly bits (lamp brackets on the footplate front?)

 

Should the back end of the valve chest stick out a bit further?

 

Any reason why no footsteps? - is FUD not up to doing these?

 

 

Can I join the queue for a copy of the boiler please?

 

Regards, Andy

 

Thanks for the comments. I like the idea of some more guide holes/dimples for lamp irons, etc and will see if we can add these before the trial print.

I will check the valve chest dimensions - as yet I haven't decided if I'm going to add bright steel end plates to these, as I will do at least for the front cylinder covers.

As to the rear steps, I think they would be too vulnerable in anything but metal so these will be fabricated and araldited on.

I will post photos of the finished trial print as soon as available and see what we can do for a boiler printing.

There also could be the possibility of an early Saint version (or even an Atlantic) if there was enough interest in having Indian Red frames.

John

 

  • Like 1

Share this post


Link to post
Share on other sites

Have you got artwork or etches for connecting rods/crossheads/sidebars?

 

Yes I have artwork, although I have to check if I completed them.

 

A straight frame Saint would be lovely (i.e. without the drop for the cab), especially as there were some that lasted until withdrawal.

 

Chris

Share this post


Link to post
Share on other sites

However, I am not sure how I am going to get weight into the boiler without a hole, unless I use lead shot, and I am unsure how to retain that (not PVA as it can give rise to expansion and I don't know the long term stability of solvent or resin adhesives and the printing plastic).

 

If you had a solid weight, you could bolt it in place, either from below through the boiler, or at one end or the other.

 

I am n expert, but I understand the cost of these 3D prints depends on the volume of materials used, and so you should make it hollow inside.

 

Chris

Share this post


Link to post
Share on other sites

Thick sections and ribs can cause distortion as they cool just like plastic mouldings. Having made it hollow you could turn or roll a lump of something and shove it in through the cab before the backhead is fitted. I'd planned to create a straight framed saint from a Dapol Hall but I hadn't got much further than stripping the donor model.

Share this post


Link to post
Share on other sites

As others have said these are by far the most handsome of the GW 4-6-0's. My first love may be for red and blue engines but I have to acknowledge that these were years ahead of their time.

Look forward to seeing this one John. Have you decided whether it will be a Lady or a Saint?

 

Jerry

Share this post


Link to post
Share on other sites

Looks very nice, always pleased to see something new from the GWR.

 

Just thinking, would it be possible to print a version 3% bigger for N gauge? I am wondering how it would look mounted on a Dapol Hall chassis? I know the wheels would be a touch small but not nearly as bad as some of the old Farish offerings.

Share this post


Link to post
Share on other sites
As others have said these are by far the most handsome of the GW 4-6-0's. My first love may be for red and blue engines but I have to acknowledge that these were years ahead of their time.

Look forward to seeing this one John. Have you decided whether it will be a Lady or a Saint?

 

Jerry

Jerry,

Thanks for the comments.

The 3D print design is based on the frame plans from GWRJ 14 of Spring 1995. This shows 2900 class Lots 185, 189 and 192 and the drawing is dated 1911. Therefore it applies, strictly, to locos 2931-2955, which were the 'Court' group, but I'm sure that adaptation to a 'Saint' proper would not involve too much, other than getting good contemporary photos.

John

  • Like 1

Share this post


Link to post
Share on other sites

Looks very nice, always pleased to see something new from the GWR.

 

Just thinking, would it be possible to print a version 3% bigger for N gauge? I am wondering how it would look mounted on a Dapol Hall chassis? I know the wheels would be a touch small but not nearly as bad as some of the old Farish offerings.

 

That's more than a touch mate, and I think it would look pretty silly. In fact I think good old Farish would probably be an example of how silly, as they specialised in undersized wheels.

 

However, it might be possible to source some bigger wheels to put into the Hall?

Share this post


Link to post
Share on other sites
Thick sections and ribs can cause distortion as they cool just like plastic mouldings. Having made it hollow you could turn or roll a lump of something and shove it in through the cab before the backhead is fitted. I'd planned to create a straight framed saint from a Dapol Hall but I hadn't got much further than stripping the donor model.

Rich,

The smokebox/boiler/firebox assembly is hollow with 1.0mm wall thickness but, at the moment, the back of the firebox/front of the cab only has the firebox hole in it. Now we are having a separate backplate, I should be able to make a bigger hole in it - say the internal diameter of the smokebox - and stuff some rolled lead in before fixing the backplate. That should sort it.

John

  • Like 1

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.