16T Mineral Etch

JimG

Western Thunderer
This is an S scale superstructure for the S scale Society Parts department and it has taken up a fair bit of my time recently, doing the artwork for the etch along with working out how the wagon body was going to go together. The body will fit on Justin Newitt's Rumney Models underframe which was designed to go under the S scale whitemetal body kit supplied by Alan Gibson a few years ago. I worked from detail drawings supplied by AndyB of this parish and they were a great help since I was able to work to the exact dimensions of every part. Justin supplied me with a CAD file of the floor of his underframe so that I could match it exactly - which was just as well since the dimensions of the whitemetal kit were not quite the same as the official drawings and the central stanchions were two inches further apart. So I had to do a bit of nudging of the prototype measurements. :)

16TMineral-001.jpg

This first test etch came back from PPD a couple of days ago and I've been staggering through trial assemblies of the parts to see if they go together as well as I hoped. :) Not quite up to Mickoo's complexity. :):):)

16TMineral-002.jpg

A closer shot shows some of the detail of how I've gone about the design. The main body wrapper at the top has slots in it to take the tabs in the stanchions. I calculated correctly and the tabs fit the slots nicely straight off the etch and I haven't had to resort to poking the slots out with a craft knife blade.

A lot of the steel work on the 16T mineral is 1/4" plate and 1/4" and 3/8" section girders. I opted to use 0.2mm nickel silver sheet which is equivalent to 1/2" in S scale. So I opted to try and represent the 1/4" thickness by half etching the door sheets to take the girders which would give a pretty good 1/4" representation. The upstanding parts of the girders are half etched to represent 1/4". You can see the four long half etched transverse door girders to the right of the main end door etch. The side doors are similarly half etched to accept 0.2mm strips to represent the 1/4" strips on the prototype. The strips for the side doors are just to the right of the side door main parts.

16TMineral-003.jpg

I made a start on the doors to see if the half etching worked and it seems to have done so. worked. Apologies for the slightly messy soldering but my solder paste has started to go off so was a bit difficult to spread sparingly. I also need to re-think the centre "T" girder on the end door since the projecting part doesn't fit properly. The side door worked very well.

16TMineral-004.jpg

The next was to try out a stanchion to see how by tab and slot worked - and it did. :):) Again, apologies for not cleaning up the solder - only testing at the moment. :):)

16TMineral-005.jpg

I'm now trying to work out the simplest way to make my stanchions. They are made from two etches. The projecting part is made by folding up the part, bottom centre above, to be almost "U" shaped. This then fits on the base part, top left, with the tabs locating through the slots in the base. The tabs also project enough to locate in the slots in the main body sides. I'm trying to work out a way of easily forming the "U" shaped part so that recommendations can be made in the instructions. The Plastikard assembly in the picture was the first attempt at a former to push the etch into to form the "U" but it wasn't successful. I'm getting better results with part bending the etch using my makeshift Hold & Fold - i.e. a six inch steel rule and a Stanley blade. :):) I then can form the "U" shape much easier by pressing into a mould. I've ordered up a Hold & Fold to see how it deals with the job. If it works well then that will probably be the way I recommend.

I also get a new syringe of solder paste - Easy Print as sold by the 2mm Society Parts so I thought that a good recommendation. It comes in a small syringe and costs about £3.

SMD Easy Print Solder Paste SN62% - Pb36% - Ag2% - 8g | eBay

It's also got a small percentage of silver content so should flow better than standard tin/lead. It seems to work very well and I was using the syringe with a hypodermic needle with success. But I then hit a problem which I saw reported in a review comment, when I started to get neat liquid flux coming out, then the delivery via the needle stopped and I found that there was fairly stiff, neat paste coming out of the syringe. The stiff paste is still quite usable and more usable than my old, stale paste so I'll soldier on and see if I work through to better mixed paste. I suspect that there could be a separation happening during storage - maybe like oil paint in a tin.

Jim.
 

mickoo

Western Thunderer
Very nice work.

Certainly braver than me with the fold up angles and one side being half etched for scale thickness, I wouldn't even attempt that in Gauge 1, let alone S scale :cool:

MD
 

Big Train James

Western Thunderer
I'm now trying to work out the simplest way to make my stanchions. They are made from two etches. The projecting part is made by folding up the part, bottom centre above, to be almost "U" shaped. This then fits on the base part, top left, with the tabs locating through the slots in the base. The tabs also project enough to locate in the slots in the main body sides.

Thanks for this....a light bulb is suddenly shining brightly for me now. I have a similar situation with the side ribs for my TBOX project. I was going to etch ribs which would be folded using a machined jig to form the proper hat channel profile. In my case I was also planning to stamp the resulting folded etch to create the prototypical deformation at the bottom of the ribs, as shown in the picture below.
tbox ribs.jpg

I was theoretically planning on accomplishing the fold and stamping by having a jig/die machined that I could use to first bend the ribs and then stamp them using an arbor press. I have no idea if it would work, but i thought I'd explore it.

Instead, I think I might try your method. I would still need to get the offset bent into the bottom of the ribs, but I think that would be substantially simpler than my proposed method. Also having the tabs extend through into the car side would make locating the ribs accurate and repeatable.

Thanks again!
Jim
 

JimG

Western Thunderer
Instead, I think I might try your method. I would still need to get the offset bent into the bottom of the ribs, but I think that would be substantially simpler than my proposed method. Also having the tabs extend through into the car side would make locating the ribs accurate and repeatable.

Jim,

I would think that my system would work. It looks as though your stanchios are made from 1/4" plate so you could be working with 0.006" material or 0.012" half-etched for the base part of the stanchion and that would form quite easily to make the step with the "U" section being etched to accept the deformed base. From my recent experience, 0.004" nickel silver will form or bend if you just look askance at it. :) You could also try brass instead of nickel silver if you wanted a slightly more ductile metal.

Jim.
 

AndyB

Western Thunderer
Jim,
It's nice to see this come to fruition.
I had quite forgotten about sending you those drawings - that was in Sept 2016.
You replied, saying "With a bit of luck and a fair wind, I might get something presentable by Christmas."
I guess you didn't say which year! :D
Will there be a 1/32 version to follow?

Andy
 

JimG

Western Thunderer
I had quite forgotten about sending you those drawings - that was in Sept 2016.
You replied, saying "With a bit of luck and a fair wind, I might get something presentable by Christmas."
I guess you didn't say which year! :D

I did start on the artwork way back then. I also got David Franks to produce suitable buffers and I got masters for axleboxes and springs 3D printed at the same time. But the big holdup came about because I had no three hole disk wheels in stock. However, David White at Slaters undertook to supply us with rolling stock wheels and the spoked ones came first. The three hole disk ones appeared a few weeks ago, which then triggered re-starting the project. :)

Will there be a 1/32 version to follow?

I'm not sure. :) It would mean designing an underframe to replace the Rumney Models one in S scale and that would need a bit of work, and I would have to see if there was interest. My own 1.32 interests are on the other side of the Grouping divide. :)

But my next project will probably be the 12T van in S scale. I've machined the corrugated ends and I'm on the way to making masters for resin casting the ends. The ends will be bridged by etched sides and the complete body will sit on another of Justin's Rumney Models underframes.

Jim.
 
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