7mm Mickoo's Commercial Workbench

Dog Star

Dog Star

Western Thunderer
Focalplane said:
And, of course, it was running backwards as they often did!
Click to expand...
Not sure about the tank engines, the valve events of the 2-cylinder 4-6-0 Collett engines when running in fore gear gave a strong engine than when running in reverse gear (source - internal Swindon report on comparison of different types of coal available in the 1950s... the repart gave the valve events in fore and back gear with the observation about power at the rail).
 
mickoo

mickoo

Western Thunderer
First test for the new WS 72XX firebox. A revised part is in the printer now and if that's okay I'll add the final details like washout plugs and mud hole cover hinge plates etc and print at high resolution.

The first test is mainly for fit and overall form, as such the clothing bands are a little thick and I've revised the mud hole cover shape a bit as well. I find it easier to see these details and shapes when finally printed and added to the model.

I think the slope back is a tad too much now, maybe pull up the rear end by 0.3 mm or so. The rear angles between clothing and cab front are good and I added the cover....not sure what it covers...to the main assembly.

I also struggled with scratch building the tank inside the cab, after three attempts (each one having one or two rivets out of place) it struck me as the perfect item to 3D print, so they're in the machine right now, as are the balance pipes that go behind the steps. I'll also 3D print the three types of tool box that fit on the cab rear shelf.

IMG_9926.jpg

IMG_9927.jpg

IMG_9928.jpg
 
Scale7JB

Scale7JB

Western Thunderer
The 42/52’s are quite attractive too. We had one a few years back when life was normal, but after jumping up in the cab for the first time, I was quite surprised by the amount of space in the cab, it’s huge!

Far preferred the cab of a large prairie, much cosier.

JB.
 
SimonT

SimonT

Western Thunderer
Mick,
this photo from Brian Daniels might help with the washout covers.
4141-01_27566044390_o.jpgIt's a 51 but they will be the same on the 72. I found the existing ones to be too big for the 94 and need to a pattern for new ones but cannot find enough information.
Simon
 
mickoo

mickoo

Western Thunderer
Appreciated :thumbs:

I can see a bolted plate on top of the firebox, that'll have to be added. Mind it's not easy to see on historical photos, so it might not be on the 72xx back in the day.....but.....it does seem to be a common trait on WR engines though.
 
simond

simond

Western Thunderer
mickoo said:
I can see a bolted plate on top of the firebox, that'll have to be added. Mind it's not easy to see on historical photos, so it might not be on the 72xx back in the day.....but.....it does seem to be a common trait on WR engines though.
Click to expand...

Mick,

I stand to be corrected, but I think all the GW belpaire boilered locos have a trapezoidal cladding cover plate on top of the firebox. There was a debate some years back as to whether that plate was green or black, to which I think the general conclusion was that the evidence for black was so thin as to be diaphanous. But by that time, the top of my 47xx firebox was black and it still is. Whatever colour, I don't suppose it got cleaned much. I did go looking for photos but could not find anything conclusive. There are not many photos of any sort from above.

atb
Simon
 
mickoo

mickoo

Western Thunderer
Another slow week on the WS 72xx.

The final firebox rendition is done but not yet fixed in place, that'll get done once all the soldering has been done on the tank tops. I ended up adding washout plugs from 1 mm sq brass rod as the printer would not clear the resin from the pocket well enough to give nice details. Also added the riveted plate on top and stuck some more washout plugs on the boiler, left overs from a MoK kit came in handy there.

The new cab interior tanks were finished and will be secured shortly one the seats have been affixed and a few other details; then it'll be the cab floor and rear bulkhead and moving on to the bunker and side sheets.

There are cast corners for the bunker but they have no rivet detail, I'm going to try and print some new corners with rivet detail on them and see how that goes. Only the lower and curved section mind, I'm considering wrapping the side sheet around to the natural joint on the rear like the real thing at the higher level.

IMG_9929.jpg

IMG_9930.jpg

IMG_9931.jpg
 
Jack P

Jack P

Active Member
Mick, Fantastic work as is the norm on this thread.

I assume the beige coloured pieces (smokebox saddle, firebox etc) are all 3D printed? If so, what printer do you use?
 
mickoo

mickoo

Western Thunderer
Kyoki said:
Mick, Fantastic work as is the norm on this thread.

I assume the beige coloured pieces (smokebox saddle, firebox etc) are all 3D printed? If so, what printer do you use?
Click to expand...
Indeed they are 3D prints, I'm not keen on the colour and will be changing to grey in the next few days, it'll save me applying a witness coat of paint to see and remove blemishes and then stripping it all off ready for the final coat.

The printer is a Form 3.
 
mickoo

mickoo

Western Thunderer
Small update on the WS 72xx, tweaking prints and a splash of colour with a witness layer of paint, it's only an acrylic right now but it'll all have to come off before Warren blatts it with cellulose.

It does show up all the little blemishes which can then be dressed before you find them after final paint. I'm not keen on the previous resin, it's really light and hard to see small blemishes, a new lot of grey arrived today which will make life easier and quicker.

New prints for the tank saddle strap and tool boxes, I offered up the cast backhead and sadly I think it's a generic type and a bit small for this engine, ergo, more printing.

The cab rear is all new to fit my sides, sharp of eye and mind will notice I'm keeping well away from the rear end for the time being, not looking forward to fabricating all that if the truth be told. But it has to be done and I'll take the bull by the horns in due course.

IMG_9956.jpg

IMG_9957.jpg

IMG_9958.jpg
 
mickoo

mickoo

Western Thunderer
Indeed and that's the basis of the impending works, it's just a case of working out how much of the corner will be printed and the best way to hide the joint and preserve details etc.
 
mickoo

mickoo

Western Thunderer
simond said:
And maybe to make them available to those of us who have a GW bunker or two in the stash?
Click to expand...
Naturally :cool:

The only variable will be the thickness of etch material where I'm going to make a recess in the print to fit.

Current thinking is to do the lower curved section and the, what I call arched section, as a print but leave the top section as brass, that will give a thin edge to the top area where the beading can be soldered to and will trap in the lower print to some extent. The only downside is the coal space floor might not be prototypical, on the 72xx I've already factored in a flat floor so that's not an issue for me.
 
mickoo

mickoo

Western Thunderer
Indeed, mind on the model this area is invisible once the footplate goes on, but I like the details it provides, which remind me I need to fabricate the spring dropper L shaped brackets, add the dropper and round snubber to the model, those certainly are visible from normal viewing angles.

I like the tie bar that holds the spring base and allows them to slide on the radial truck, clever, never knew how they did that and suspected they were rigidly fixed and just flexed when the radial moved.
 
Dog Star

Dog Star

Western Thunderer
I suspect that the spring rods are replacements given that the rods seem to be barstock with threads at each end.... I expect that the originals were forged bolts with a head on top of the two part spring bolt pad.
 
You must log in or register to reply here.
What's New?
Top