Work in progress: Scratchbuilding a mineral wagon in 0-scale

[Hawk]

 

The prototype for this project is a steel underframe wagon with a wooden body.



It was built for the meter-gauge Thamshavn Railway in 1908. It was used for transporting copper ore from the mines at Løkken to the port of Thamshavn some 25 km further north.

Even if the protoype is rather obscure, I think the construction of the wagon is quite typical for European rolling stock built in the early 20th century.
All the beams of the underframe and all other hardware is etched in 0,25mm nickel silver.

 

The long beams with the narrow flanges poses quite a challenge during the folding up process. I suspected this before starting to build my kit, so I persuaded my good modelling buddy Øistein into making me two pairs (the picture shows just one pair) of custom-made bending bars. These bars make it possible to fold up the beams in one go. 

 

I used the proven and tested concept of W-irons with springing by guitar strings. I learned about the concept at the CLAG website, and I copied the design with very few modifications.
The most import change I made is that I mount the W-irons directly to the solebars. Using brass rivets in etched holes to keep everything in position during soldering assured a sqare an level frame.

 

 

 

 

I have not counted them, but I think there are more than 100 turned brass rivets in each wagon. 

 

I also decided to omit bearings of any sort. The axles are narrows down from a diameter of 3mm to just 0,8mm at the journal boxes. So the steel axles just run in plain holes in the movable part of the W-iron. I was a bit worried about the rolling properties of this set up, but the wagon turned out to be quite freerollling. Not quite as goood as pinpoint axles in brass bearings, but good enough. 

 

 

 

 

The cosmetic leaf springs with hangers and journal boxes are meant for an entirely different type of wagon, and these brass castings are in adition to the couplers some of the very few commercial parts that I have found suitable for my Thamshavnbane projects. After all, to my knowledge I am the only person in the world modelling the TB in 0-scale!

 

 

The body is not yet finished, but it is going to be built board by board from real wood with brass castings for hardware.
The boards for the model has milled tongue and groove just like the prototype. A lot of experimenting went into making them model boards, but wood for several cars are waiting to be assembled.

 

The master for the custom castings was printed on a Solidscape wax printer from a 3D model that I made in Solidworks. The actual casting was done by Dave Sciacca of Valley Brass & Bronze.

 

 

 

I have also started to experiment with painting of the wood and blackening of the brass

 

 

 

The plan is to make the doors operational on at least one model.

 

 

 

All in all I hope to build 11-13 of these wagons. 

I hope that the images show how things fit together, but feel free to ask questions or make comments! 

Edited August 11, 2023 by Hawk

[Kenton]

The "craftmanship/clever" button just feels dreadfully inadequate, but then that's also how I feel.

 

Stunning detail! Even for 7mm scale.

[hobbyhorse]

Wow, astonishing work.

David does a lot of our casting, master of the art.

 

Simon

[Pugsley]

The effect on the strapping is superb! (As is the whole thing).

[Hawk]

Wow, astonishing work.

David does a lot of our casting, master of the art.

 

Simon

 

There are a lot of people that deserve credit for making this project possible. 

David has already been mentioned, but here are a list of some other people that deserves credit: 

 

-Erik Olsen for making the wheels. A fine article on his techniques can be found here. 

-Erik Walde for designing the leaf spring castings and working "Norwegian Couplers". (Not yet added to the model)

-Erik Holt of Erik Holt Kappler Mill & Lumber Co. for making the excellent stripwood for the body.

 

PPLtd deserves credit for the very crisp etchings. Their service is fast and reliable, and they will take on your job no matter how small the sheet is. 

[3 link]

The "craftmanship/clever" button just feels dreadfully inadequate, but then that's also how I feel.

 

Stunning detail! Even for 7mm scale.

 

Ditto.....

 

Martyn.

[The Nth Degree]

Fantastic. The wax prototyper looks to have done a very good job of the masters.

[Hawk]

On 11/02/2015 at 21:25, Pugsley said:

The effect on the strapping is superb! (As is the whole thing).

 

Thanks to all for the positive feedback! 

 

By the way, this thread was initiated by another forum thread discussing the Bill Bedford W-irons. 

 

Here is an image that shows my implementation of this concept: 

 

 

I saw no need for connecting the W-irons across the wheelset, but pinned them directly to the side beam (solebar?) This way the design can be used on  wagons that have exposed frames. Once blackened, the arrangement will be barely visible, me thinks. 

Edited August 11, 2023 by Hawk

[garethashenden]

Thanks to all for the positive feedback! 

 

By the way, this thread was initiated by another forum thread discussing the Bill Bedford W-irons. 

 

Here is an image that shows my implementation of this concept: 

 

 

 

I saw no need for connecting the W-irons across the wheelset, but pinned them directly to the side beam (solebar?) This way the design can be used on  wagons that have exposed frames. Once blackened, the arrangement will be barely visible, me thinks. 

I think the reason for connecting across the wheelset is to ensure alignment. If that is established in some other manner then there's no need.

[Hawk]

Fantastic. The wax prototyper looks to have done a very good job of the masters.

 

Indeed he did. It was Precision Wax in the UK that printed the master. It took a couple of reprints before the master was perfect, but they kept at it until everything was fine. I can recommend them highly for wax printing. 

[F-UnitMad]

I have not counted them, but I think there are more than 100 turned brass rivets in each wagon. 

 

 

I wouldn't worry - using real tongue'n'groove wooden boarding is one in the eye for the most fanatical rivet-counters!!!

Awesome stuff.

[david.hill64]

You see lots of excellent stuff on this site, and then something like this comes along that is just so good it's hard to find the correct words to express the admiration for the exquisite craftsmanship that has gone into this. Well done indeed!

[Hawk]

You see lots of excellent stuff on this site, and then something like this comes along that is just so good it's hard to find the correct words to express the admiration for the exquisite craftsmanship that has gone into this. Well done indeed!

 

Thanks for all the kind comments! Hope that my postings might inspire others to go ahead and try their hands at some scratch building following obscure prototypes!

 

Speaking of the prototype, I lack information on the inside of the wooden body. Have anybody heard of a wooden mineral wagon were the floor is covered by thin metal sheeting? My guess is that the wooden floors of a gravity-emptying mineral wagon would get worn out quite fast. 

Edited February 12, 2015 by Hawk

[Fat Controller]

What absolutely wonderful modelling!

There is a precedent for a metal covering to the floor I believe; didn't some of the end-tipping china-clay wagons have a galvanised steel sheet fitted on top of the floor timbers?

[Adam]

Speaking of the prototype, I lack information on the inside of the wooden body. Have anybody heard of a wooden mineral wagon were the floor is covered by thin metal sheeting? My guess is that the wooden floors of a gravity-emptying mineral wagon would get worn out quite fast. 

 

I'm not sure about that, wood is pretty tough. Wood was also easy to repair and cheap. The china clay wagons Brian mentions are the only UK examples I can think of (and in that case, to ease the flow of the load out of the wagon - other china clay vehicles had floors laid the length of the wagon rather than across which was usual). End tipping from wooden-sheeted wagons was normal for thousands of  vehicles on a daily basis from, for example, the south Wales ports, and wooden bodied and framed hoppers in the north east of England were the norm until the days of horse-hauled waggonways until the 1960s and they certainly weren't metal plated. 

 

Designs for iron ore wagons seem to have become more steel-based earlier but I suspect that's partly because of the density of the load and the need for heavier duty vehicles. Looking at the design of the particular vehicle, however, I wouldn't know but the v-shaped 'floor' might well have been steel but I would be very surprised if the insides of the doors were anything other than raw, untreated wood.

 

Superlative modelling.

Adam

[Hawk]

Thanks to all for the interest in my project!

One of the reasons for the metal floor speculation is this image:

 

 

You can glimpse the floor behind the open door, and to my eye it looks like the floor is smooth. I have tried to increase contrast and lighting, but I have not succeded in finding even traces of grooves or texture in the floor.

 

 

On the other hand, the arguments made by Adam against a metal floor sounds reasonable, and I am having a had time making a descision...

 

 

Please feel free to join the speculation!

Edited August 11, 2023 by Hawk

[Nimbus]

Indeed he did. It was Precision Wax in the UK that printed the master. It took a couple of reprints before the master was perfect, but they kept at it until everything was fine. I can recommend them highly for wax printing. 

Did you have to iterate through the full process to casting in order to arrive at perfection, or was it enough to examine the waxes only? Also, did you need to involve your caster at the design stage, to make sure your waxes were a castable design, or to advise on sprueing?

 

I'm wondering how reliably some sprung Timken axleboxes could be made in  4mm scale by this route.

 

The Nim.

[Adam]

It certainly looks like metal sheet over planks but as you say, it's hard to tell. For iron ore in a cold climate this would be sensible.I can't think of a UK-design of wooden hopper that had anything like that, but then, I can't think of a UK mainline type with side doors in quite this fashion...

 

Adam

[Fat Controller]

It certainly looks like metal sheet over planks but as you say, it's hard to tell. For iron ore in a cold climate this would be sensible.I can't think of a UK-design of wooden hopper that had anything like that, but then, I can't think of a UK mainline type with side doors in quite this fashion...

 

Adam

The only two types I can think of that used this idea of a hopper discharging to both sides were the Consett bogie ore hoppers and the ones that operated around the Chichester area on aggregate traffic. Both many decades later, of course. 

The concept  seems to have been popular in Germany, and also in parts of Northern France and Belgium; there are regular ore, coal and lime workings around the Dunkerque area using modern iterations of the design.

[Hawk]

Did you have to iterate through the full process to casting in order to arrive at perfection, or was it enough to examine the waxes only? Also, did you need to involve your caster at the design stage, to make sure your waxes were a castable design, or to advise on sprueing?

 

I'm wondering how reliably some sprung Timken axleboxes could be made in  4mm scale by this route.

 

The Nim.

The biggest challenge for the master was that the long, thin design made the waxes very brittles. I wanted the irons to be just 0,3mm thick, but had to increase the thickeness to 0,4 mm. Several other printing services refused to go below 0,5mm.

 

The other problem was the hex nuts. Most of these had a bolt sticking up, and this bolt had a diameter of 0,3mm and height of the same. These printed OK. But on each iron I needed to drill a pair of 0,3mm holes for nickle silver pins that are used for pinning the fittings to the wooden sides. These blind holes should also have a diameter of 0,3mm and a depth of same. The problem was that some of these holes pinted just fine, and som others closed up. Prescision wax needed to fine-tune their machine and process to get the print right, and I think they tried two or three prints before they succeded. My impression is that Prescision Wax takes great pride in their work, and that they threat every customer just the same, no matter how small the job is. I will certainly use the company in the future.

 

By the way, the pocess for these parts were a bit unconventional. Wax prints are usually used for making a one-off metal master wivh inturn is used for making a silicone rubber mould for the production waxes. With a metal master, you can choose between using heat vulcanisation rubber or room temperature vulcanisation rubber (RTV-rubber).

 

But Dave made a RTV-master directly from the Solidscape wax print. This is not an easy task with a fragile wax master like this. Prescision wax was hesitant to even ship the wax print to the US, they had serious doubts it would survive the journey.

 

I do not know the details of your master, but I feel certain that if anyone will be able to pull it off, it would be Prescision Wax and Dave Sciacca/Valley Brass & Bronze.

[garethashenden]

I can see the ends of floor planking but nothing going into the interior. Two possibility are 1) metal sheeting over the whole thing or 2) metal strip along the bottom edge.

[Hawk]

On 13/02/2015 at 14:45, garethashenden said:

I can see the ends of floor planking but nothing going into the interior. Two possibility are 1) metal sheeting over the whole thing or 2) metal strip along the bottom edge.

 

 

I tend to agree. At © I think we can see a groove in the board. If you look futher up in the opening, there is no sign of texture or cracks. The lighting is also better here, so any cracks should be visible ( B ). This indicates that there is metal sheeting covering everything.

 

 

Scrutinizing the image I have also discovered som shadows behind the hinges (A). Could there be some brazing supporting the fixed three plank part of the sides?

Edited August 11, 2023 by Hawk

[buffalo]

Looking at the 'sheeting' in the very centre of (c ), it looks to be at an angle, so it looks like there is a central inverted V shape along the centre of the vehicle. This would allow the load to be fully discharged with nothing remaining on the floor. If I'm right, this looks to be covered in metal sheeting as there's no sign of any plank grooves between (c ) and ( b )

 

Nick

Edited February 13, 2015 by buffalo

[Hawk]

Looking at the 'sheeting' in the very centre of (c ), it looks to be at an angle, so it looks like there is a central inverted V shape along the centre of the vehicle. This would allow the load to be fully discharged with nothing remaining on the floor. If I'm right, this looks to be covered in metal sheeting as there's no sign of any plank grooves between (c ) and ( b )

 

Nick

You are right. That the floor resembles an inverted "V" is quite obvious from the prototype shot at the very beginning of this thread. You can clearly see a triangular opening in the end.

[Pugsley]

I tend to agree. At © I think we can see a groove in the board. If you look futher up in the opening, there is no sign of texture or cracks. The lighting is also better here, so any cracks should be visible ( B ). This indicates that there is metal sheeting covering everything.

Yes, I agree, the entire area is metal sheeted.

 

Scrutinizing the image I have also discovered som shadows behind the hinges (A). Could there be some brazing supporting the fixed three plank part of the sides?

I think that is bracing there - if you look just to the left of the hinge on the far right, I think you can see the same bracing for the other side.