7mm The Old Man's Workbench - tales of a rivet side

Dog Star

Western Thunderer
I'd go for cut n' shut Graham - it's about saw kerf width so splitting it down the middle and if necessary plating one side over the joint with a small piece of scrap etch....
This suggestion from Bob is a good candidate - 25th is about twice the width of a 4/0 piercing saw blade so two straight cuts shall do the necessary.

Why two, other than to get the necessary reduction in width? Consider the queen posts to be numbered 1 to 4 from left to right... if I cut between 1 and 2... and between 3 and 4... then I shall maintain the alignment of the outer queen posts with the solebar and the inner queen posts with the cut-outs of a cross-member (for the truss girders) further along the underframe.

Investigation and success shall wait for the weekend as trackwork is beckoning.

regards, Graham
 

Dog Star

Western Thunderer
So is the queen post etch wider than the bogie transoms etc ?
I think not, my instinct is that all eight of the cross-members were the same dimension when cut from the etch.

As to why the cross-members are too wide, I have asked Andy Beaton for some information to help me establish where I went off the intended path. To be clear, this kit looks very nice and I do not think that the problem described here is a consequence of the design of the kit.

regards, Graham
 

Dog Star

Western Thunderer
An update on the question of the day - where did I go wrong?

Andy has provided information about "expected" measurements for the side/floor and solebars after folding :thumbs: . Whilst Andy's measurements were taken from a constructed example of the kit and hence may have a tolerance factor the information points at the manner in which I made the folds of the sides/floor etch (rather than the folds of the solebar etches). There is a difference of around 0.5mm between my measurement between sides and the same measurement made by Andy. All of which indicates that when I deepened the side/floor fold line with a miniature triangular file I may have moved the centre of the fold...

Whilst this experience is annoying the occurence is not going to stop us from purchasing more examples of this kit for we think that 3 or 4 carflats behind Mk.1s are going to be an atractive sight, particularly with Westerns in Maroon.

regards, Graham
 

Dog Star

Western Thunderer
A question for those who have built an A4 from one of Martin Finney's 7mm kits.

If the cab is completed before painting... the inside of the cab is somewhat busy and I feel that painting is likely to be drawn-out and difficult, particularly the inside of the cab sheets towards the front of the cab. If the cab inside is painted as construction proceeds then there is a chance that the paint finish could be damaged as work proceeds.... and this approach needs thought to ensure that the assembly of some parts does not get in the way of adding other items later in the build.

So, follow the instructions as written or paint-as-you-go?

How easy is adding / removing the backplate, which is a push fit into the rear of the boiler platework, after the floor w/m castings and cab seats have been fitted?

thank you, Graham
 

Rob Pulham

Western Thunderer
Hi Graham,

I take it that the roof isn't removable as standard?

If it's any help the DJH instructions for the A3 have you fitting the back head and then the seats- after painting.

It's good to see this back on the table - a bit rich coming from me I know:rolleyes:
 

Dog Star

Western Thunderer

richard carr

Western Thunderer
Graham

I haven't built the Finney a4 but I always build the backhead as a separate item and add it after the loco has been painted, that certainly worked on my Finney V2. As the roof is removable that shouldn't be too hard to do.

Richard
 

Dog Star

Western Thunderer
... I always build the backhead as a separate item and add it after the loco has been painted, that certainly worked on my Finney V2. As the roof is removable that shouldn't be too hard to do.
How have you retained the casting in place?

Clearly I may have mis-judged the space required to remove the A4 backplate, I need to do some 3D trials with the cab parts and some blu-tack (not white tack... as this A4 is to be a BLUE engine :thumbs: ).
 

richard carr

Western Thunderer
Graham

I'm sure it's glued in place but as it's over 13 years since I built it I will need to check when I get back home from holiday.

Richard
 

mickoo

Western Thunderer
The only issue I can forsee to removing the backhead easily is it's width at the base, it should be full cab width, hence the washout plugs in the cab side sheet, I'm guessing the safety valves are not attached to the backhead but in a recessed trough that is part of the roof fitting? I've yet to unwrap all of mine (it will be BR green) or open the instructions but that day is drawing ever closer :thumbs:

However, I did take a look at the resin boiler casting at the weekend and the rear bulkhead is quite substantial, thick enough to allow the back head to be screwed into place if required I'd of thought......once you've wriggled it in there of course, and, assuming the backhead is V shaped to match the cab front.
 

Dog Star

Western Thunderer
April saw Henry Harvie, the Head Ganger for Hartley Hill, in a bit of a panic... he had received notice that there was to be a ballast working to the station for renewal of the Up Goods and Up Main. The reason for Henry's tizwas is that there is a deficit of suitable wagonry for transport of the necessary materials. Resourceful as ever, Henry was on the blower to the local Wagon Repair Yard and asking for assistance - whereupon said yard offered some new fangled 21T hopper in place of the typical rake of 5T one planks.

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dogfish2.jpg

dogfish3.jpg
Peter has been building this MMP kit and the yet-to-be-finished model has made an appearance on Hartley Hill for running trials. As we get closer to completion the task of keeping the model clean gets more difficult because of the delicate handrails / operating rods / brake gear. Even though the model gets immersed in a soda bath after every soldering session, to neutralise the flux, and then washed with soap and warm water, the metal suffers from some tarnishing and flux splash marks.

If you have built this kit, or something similar, what cleaning / preparation method did you use prior to painting?

thanks, Graham
 

Dog Star

Western Thunderer
Safety Flux and C&L 145 degree solder generally with some C&L 100 degree solder creeping in for attaching castings - although the axleboxes and springs are secured with 5 minute epoxy.
 

Ressaldar

Western Thunderer
Hi Graham,

nice model in the making there. I would suggest an extended soak in A strongish solution of Viakal with some gentle brushing (soft bristles) and then a good soak in warmish water.

cheers

Mike
 

richard carr

Western Thunderer
Graham

The flux is the problem, I use the one fom Simon Varnam on his Building O gauge on line site it keeps models so much cleaner and just needs a quick rinse in cold water at the end of each session to wash off the residue.

You should be able to get most of that off with a tooth brush as Mike suggests above.

A lovely model Peter's done a fine job on that.

RIchard
 

Dog Star

Western Thunderer
I would suggest an extended soak in A strongish solution of Viakal with some gentle brushing (soft bristles) and then a good soak in warmish water.
You should be able to get most of that off with a tooth brush as Mike suggests above.

Sound advice... in this case I am not confident of the outcome...

* immersing the entire wagon in any solution with water as the solvent is not good news for either the tyres or the journals...

* getting any form of brush into the middle of the underframe is probably difficult because of the proximity of either the brake gear (from below) or the hopper opening gear / handrails (from above).

I am inclined to use some sort of acid cleaner applied by a foam pad or small bristle brush followed by a directed water jet or a damp cloth/tissue.

Whatever the outcome for this model, Peter and I are going to consider a different assembly order in which selective painting takes place as assembly progresses - maybe even using chemical blackening.

thank you, Graham
 
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