7mm Mickoo's Commercial Workbench

mickoo

Western Thunderer
Great idea Mick! :thumbs: Wish I’d thought of that, whilst doing my drawbars and buffer beams on my 4MT tender...


Regards

Dan
It also allows you to add the intermediate buffers and rubbing plates and allows soldering from the rear, especially the intermediate buffer spigots, once the draw bar plate is fitted, access to the rear of those spigots is near impossible; which means soldering from the front....and more cleaning up.

I also added the riveted strip along the top of outer frames before fitting them to the floor, instructions say the other way. Experience has shown me that soldering a thin half etched strip up and under there is a wide open door for Captain cock up and his merry crew to visit, and, near impossible to clean up effectively.

I did the same with the H15 bogie side frames, made the laminates up, dressed the edges all nice and smooth, then trimmed the twist tabs back to leave just enough of a tab to locate the side frame and then dabbed with solder. The same applies to the bearing plate/stretcher, there are six tabs that come up through inner frame to hold that laminate in place, if I had left them as twist tabs then I would of been dressing back on a visible surface and you always end up with some form of marking, that once painted, looks a witch.

My view of twist tabs is that they are handy, and very welcome in most cases, but not a mandatory usage.
 

Dan Randall

Western Thunderer
Hi Mick

Hmmm, yes. I was only looking at those long rivet strips yesterday evening.... Think I’ll use Araldite to attach mine. :))

I thought it odd that the intermediate buffers were just solid castings, so I laboriously removed the cast-in heads, drilled through the base plates and substituted a pair of sprung (4mm scale), Slater’s buffers, as seen here....
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Pretty daft thing to do really, as they’ll never really be seen, once the loco and tender are coupled.... :rolleyes:

I’ve still several things to attach to the entire tender (including the missing hinge on the coal space doors!), but it’s definitely getting there and then of course, it’ll need a pretty serious clean. I might have to invest in a larger ultrasonic cleaner though, as my current one is way too small. I’m looking forward to cracking on with the loco, once the tender’s finished....
7EB1C3F2-1DA4-484C-822E-433B282C1AFF.jpeg

Regards

Dan
 
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mickoo

Western Thunderer
Ooh, bad attack of the killer fungus, best thing I've found is more flux, laugh ye not. Small brush, dab a bit on and just rub the area, it'll clean that green :shit: off then spray Limelite....in my case......and after 15 seconds wash away with hot water; seems to do the trick here.

For future reference, I'm sure that fungus is caused by hot flux spatter, best bet is to wash it right away, within the hour or less, that way it can't get a hold.

The 4MT chassis, or bits of, have been washed many times already, sometimes with Limelite, sometimes with fairy washing solution, other times with hand soap.....Imperial Leather botanical garden & raspberry blossom....for sensitive hands of course.....:cool: Another trick is to blot dry immediately, kitchen roll is best, leaves less fibres.....otherwise I find the water (we have hard water here) leaves a stain.

Of course you could forsake all that and just ultrasonic clean at the end :)) but my gut feeling is that is won't get rid if that green fungus effectively.

Front end looks nice.....tender does as well despite the killer fungus.
 
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Scale7JB

Western Thunderer
Indeed not, the tabs help....most of the time, but be assured it is definitely soldered. The MOK tab system is a huge aid to making clean models and hiding solder joints.

There's a few that I personally (and it is my own personal opinion based on my build methods) think are not so helpful. These are the ones that pass through the drawbar and buffer beam base plates.

Each of these is made up of two lamination's, a full thickness rear (base) and a half etched detailed overlay. You apply the base over the tabs, twist, solder and clean up, simples, then you add the overlay. The problem now is that it's almost impossible to dress the edge between the two and make it look like one piece; you end up with a visible joint between the two in some awkward and difficult areas to clean nicely.

For these areas, I trim the tabs back to material thickness, thus they are simply tabs, not twist tabs. Then I laminate the buffer beam and drawbar plate separate from the model, clean all the edges to make it look like one piece, offer to the model and then dab solder where the tabs are, job done.

It's a little more complicated but overall actually faster and it's a whole lot easier dressing laminated edges when the parts are flat or in the vice.

This reminds me, there are two tabs on the Australian loco on my workbench that I failed to clean before soldering up as a component. No chance of filing now. I’m thinking a sharp scalpel blade to chop them away and then some grit paper to clean up held by a pair of tweezers.

JB.
 

mickoo

Western Thunderer
This reminds me, there are two tabs on the Australian loco on my workbench that I failed to clean before soldering up as a component. No chance of filing now. I’m thinking a sharp scalpel blade to chop them away and then some grit paper to clean up held by a pair of tweezers.

JB.
Ouch, hate that when it happens. I use a dremel slitting disc if theres space, just nibble away at the tab, problem is, I usually go a bit far and mark the surface, not good if it's a visible one. I also have a rubber disc impregnated with grit, you can get them from cooksongold.

Essentially they're polishing discs, green is quite soft but black is much harder, it'll easily take tabs off or trim back metal, they also mark the surface as well but the marks are more like ripples in the sand than the rough surface you get from a slitting disc.
 

Cliff Williams

Western Thunderer
Beautiful work! I have the Ivatt and King Arthur in the queue to do, this is spurring me on with some stragglers and clear the way to them.
Keep up the good work!
 

mickoo

Western Thunderer
Morning,

I am sure some have seen Longbows article about the chemical composition of the green deposits. Which solder/flux combination do you use for etched kit construction? I am trying to get Ammonia in a small quantity to test if the copper phosphate is dissolved in Ammonia. I remember that you could buy it in every drugstore, but no more. :rant:.

Michael
And Acetone too if I read correctly, that I do have in the form of cellulose thinners, what I don't have is any green fungus to test it on :(
 

simond

Western Thunderer
EIYF. In this case, eBay is your friend... ammonia is available. Horrid stuff.

though I got my acetone from our local friendly fibreglass company. Had to sign the book, iirc.

Certainly had to sign my life away when we bought some conc. Nitric acid for work, that’s not nice either.

hth
Simon
 

michael080

Western Thunderer
I tried it with Acetone, but it evaporates so quickly that I couldn't get any green trace on my cotton bud.
The best way to remove copper phosphate is probably grit blasting. I had a few spots inside the bunker of my 5101 and the were removed in seconds.
Mechanical cleaning : chemical cleaning 1:0

Michael
 

mickoo

Western Thunderer
Have you tried flux, after all, it is supposed to clean metal before soldering......

I've tried it on a few stains and it removed them, not green ones mind, the less obvious tarnish type stains.
 

mickoo

Western Thunderer
End of weekend on the MOK 4MT, not as far as I planned/intended five days ago, but further than I expected if I'm honest.


It's all loosely fitted right now, there are a few gaps and tight spots to tweak between the inner core, outer shell and upper front bulkhead before finally soldering it all up. The better the fit, the less solder, the less time taken to clean up.

I also need to open out the front side sheets to take the tablet catcher recess.

IMG_9562.jpg

IMG_9563.jpg

IMG_9559.jpg

IMG_9561.jpg
 

mickoo

Western Thunderer
Tony, few kits provide specific provisions for DCC or sound, but most have room for the decoder and speaker.

I don't think there will be any issues fitting DCC and sound into the 4MT, it went in the Armstrong and that's a much smaller engine.

A bigger issue is discreet pickups on the very exposed engine frame, wiper pickups are out but I have some very small discreet plunger picks up from our European friends ;).

Tender pickups would be easier and require much less surgery so I may opt for that route, or a combination of both.

This week will be back to the H15 and next weekend I'll pick up the 4MT for more progress, I'll bounce between these two until their both done as well as picking off some Garrett bits along the way.
 

Focalplane

Western Thunderer
I know "American pickups" are not very popular in the UK but I would think that, with an insulated coupling between loco and tender the 4MT should behave well and look good, particularly as compensation is keeping all six pickup wheels in contact with the rails.

Just my 2 cents, Paul
 

mickoo

Western Thunderer
Mick,

H15 ? Hope you mean N15, unless you have another kit on the go as well ;)

Ian
Slip of the finger, N and H are close to each other on the keyboard, that's my excuse. Reality is, I can't keep up with all these N's, H's and S's they use on that railway that paints em all funny colours :p
 
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mickoo

Western Thunderer
I know "American pickups" are not very popular in the UK but I would think that, with an insulated coupling between loco and tender the 4MT should behave well and look good, particularly as compensation is keeping all six pickup wheels in contact with the rails.

Just my 2 cents, Paul
Fair point, the recent 47xx I've just completed used the US style pick up, I just used an insulated bush in the draw bar and ran a single cable across.

The only faff is having to short out Slaters wheels, slitting the rear of a spoke, adding wire and soldering to rim and hub; the 47xx had cast wheels so no such issues.
 
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