S7 scratch building

[airnimal]

First the good news ! I have a new tray to model on so I can carry it from my workshop and set up in the living  room and clear it away very quickly. 

 

Then the bad news ! This van is going to be scrapped. I have made another fundamental mistake.

I put it down to a combination of thinking about trying to find a new house and trying to get the old one ready for selling, plus I was at the hospital on Tuesday. Along with lockdown and lack of information about the prototype doesn't help as well as the lack of photographs all combined to making  mistakes a whole lot easier. 

 

Will I be starting again ? Well I will be going out for the rest of today so I will have to ponder on it and think things over. Perhaps I need a brake from modelling for a short while and concentrate on clearing out the clutter before we put the house up for sale.

[Dave Hunt]

What was wrong with it Mike?

 

Dave 

[airnimal]

Dave, just the simple matter of a plank missing.  There is only one photograph as far as I'm aware of the 7 ton van and it's a bit smaller than the 10 ton van of the same design which we have better photographs.  The works drawing of the smaller van is different to the only photograph that we have of it. Trying to construct this van, I took my eye of the ball regarding the number of planks and concentrating on the overall height of the body and where the planks lay in regarding to the farming.  

I dont know which size van Marc made when he released his kit or which drawing he used but building something accurate from so little information is never going to be easy. Now I know were I went so wrong makes me feel better about it and I will continue and make another. 

 

NeilHB suggestion about the Posca pens was brilliant.  Mine came yesterday and I tried it out on a pair of stainless tweezers. Yes it does as Neil says and produce a Matt black finish but I was able to rub it off when it had dried. These pens are not the same as magic markers in which the steel is stained but are paints.  So I did it again  and when it had dried I painted a coat of Matt varnish over it. This time the results were just what I wanted, a perfect finish that appears to be hard wearing. Good call Neil. 

 

 

Edited March 15, 2021 by airnimal

[chris p bacon]

I'm going to take up bin diving if that wagon is the quality of things that end up in it.  

[airnimal]

I have applied the Posca pen to the wheels of the L&Y pug. I cleaned them with methylated spirit on a cotton bud before applying. I then painted them with Testers dull coat Matt varnish. This was successful on about 90% of the wheels but it removed a very small amount of the black. I let them dry and then went over them again with Posca pen. This seems to have been successful now they are all dry and rubbing them with a dry cotton bud doesn't have any effect on them.  I think the loco does look better for the work. I just need to tone down the coupling rods to a more work stained loco.

[NeilHB]

Painting the rims has made a big difference Mike, it looks very good. 

[Simond]

Wheels look hugely better, a bit of yellowed, oxidised, baked-on oil on the rods...

[airnimal]

Now here is a dilemma  ! The works drawing for the 7 ton van show 9 planks but the one photograph we have have shows 9.5 planks. Do I increase the height of the model or do I decrease the size of the planks to fit the overall height. That half a plank makes a difference visually but which way is the correct  way. 

I have made a basic frame but the one photograph we have is quite  small and not very easy to scale off.

[Mol_PMB]

Can you post the photo and drawing here so we can offer a second opinion?

Does the photo include any other vehicles of known dimensions that could be used to inform the decision? 

[MarcD]

There are a few NSR vans all look pretty similar but are slightly different dimensionally. I will have a look at what drawings I have. 

Marc

[MarcD]

Mike 

I have sent you a PM. hope the contents help.

 

Marc

[airnimal]

 Mol_PMB, I am not sure about copyright to post photographs and drawings from books. I have in the past posted little snippets of drawings but I am unsure if this is acceptable.

I have decided to make the planks fit the space between the top and bottom frames but within the overall dimensions of the works drawing. I think after all these years a bit of guesswork is always going to be necessary.

 

So I have cut the sides and ends out and hopefully I can make a better job this time, but I have said that before. 

 

I don't have any more of the vacuum shaped roofs left so I'm going to use a cut down one from a unknown plastic kit.

[Compound2632]

Are we looking at G.F. Chadwick, North Staffordshire Wagons, Fig. 28 and Plate 40? I would go with the dimensions on the drawing but the planking as seen in the photo. 

Edited March 16, 2021 by Compound2632

[Caley Jim]

15 minutes ago, Compound2632 said:

I would go with the dimensions on the drawing but the planking as seen in the photo. 

It’s my understanding that the drawings would show the required dimensions, but occasionally the wagon shop would use what planks they had available to fit these dimensions. It may have been that the planks they had were slightly narrower than specified in the drawing so they had to put in a narrow one to make up the height. 

 

Jim 

[Compound2632]

23 minutes ago, Caley Jim said:

It’s my understanding that the drawings would show the required dimensions, but occasionally the wagon shop would use what planks they had available to fit these dimensions. It may have been that the planks they had were slightly narrower than specified in the drawing so they had to put in a narrow one to make up the height. 

 

Or possibly the draughtsman didn't bother to draw the planks correctly, knowing that the shop would use material of standard dimensions..

[airnimal]

I had already decided to fit the correct numbers of planks to fit the known dimensions so it looks right to the photograph.  I have the basic shell now ready to fit the doors and other framing. 

I will do another hour now but we have our grandchildren tomorrow which doesn't allow for any modelling to take place. They are a little young yet to get them helping but the first place they want to go is to see the trains in grandad's cabinet.

[airnimal]

We survived the 2 little boys today, they have such energy for us old folk.

 

Back to the replacement van and new doors. Graham ask how I made the doors a short while ago so I took a couple of photographs  this time. The door pillars are made from 40 x100 thou rather than 60 x 100 thou which the other framing is made from so making the backing of the doors 20 thou proud. It's not a lot but adds to the overall  look. 

[rocor]

On 16/03/2021 at 16:30, Compound2632 said:

 

Or possibly the draughtsman didn't bother to draw the planks correctly, knowing that the shop would use material of standard dimensions..

 

As a former draughtsman I can affirm to that being a strong probability. The dimensions on an original drawing also should not always be trusted, as workshop personnel do not always bother to report mistakes on drawings back to the drawing office. They just make their own corrections. 

[Mol_PMB]

1 hour ago, rocor said:

 

As a former draughtsman I can affirm to that being a strong probability. The dimensions on an original drawing also should not always be trusted, as workshop personnel do not always bother to report mistakes on drawings back to the drawing office. They just make their own corrections. 

When I worked at Derby Carriage Works in the early 2000s, I recall some Mk3 coaches coming in for crash damage repairs. New body pressing parts were ordered according to the original drawings, but when they turned up they didn't fit. After scouring the factory for old hands with good memories, one chap said "Oh, those bits never fitted, we always had to cut them down on the shop floor".  And the production run had been more than 1000 vehicles over 15 years!

[airnimal]

Well I have got back to where I was before I decided that the planks were not correct but this time I hope I have it right. The wrong one will hopefully become a line side tool shed along with the brake van. Thinking about the NSR wagons I have recently made, they are amongst my favourite in all the wagons I have. I find the livery very pleasing and the wagons very simple in design. Coupled with the area of the Potteries with there canals and bottle kilns in which these wagons would  operate has it all for me. One problem I have I don't have a NSR engine to pull them. I did have a kit for a D class but I sold it because I didn't feel I could have make a good enough job of it. Loco building isn't for me although I have made plenty in the past I can never make them to a standard that pleases me.

Perhaps if there was a really good kit of an early NSR loco I might be tempted to have another go 

but I don't think that is very likely as I don't think that there are many NSR modellers about to warrant anybody a kit manufacturer to go down this route. I will have to keep my eye out for a second hand loco that could be converted to S7 standards.  Perhaps I could commission one from a good scratch builder, but who ?

 

[airnimal]

There is a famous saying about not being able to see the woods for the trees. This just about sums me up !

I started this second van because I got the number of planks wrong on the first one. Then a friend mentioned did they build the doors in different styles. What......

Staring me in the face was the obvious mistake I completely missed again. O dear or words a bit stronger were muttered reaching for the drawings and the photographs. 

The first build was made using the drawing of the 7 ton van but it is different to the drawing of the 10 ton van. The doors framing goes the other way up 

 

Thankfully I had got it right the second  time. But how did I not notice such a glaring error ?

Now the question is did other people notice and were to polite to mention it to me ?

I have a thick skin so if you know I have dropped a clanger, please don't hang back and point  any errors you spot.

I wonder if the works ever did build any of the wagons with the doors the other way up ?

[Mol_PMB]

The version on the left makes more sense structurally, in that the diagonal member is in compression when supporting the weight of the open door. With traditional timber joints it's easier to make them strong in compression rather than tension, and a baulk of timber is fairly resistant to buckling in compression. Iron strapping is the opposite - it can be quite thin yet strong if loaded in tension, but in compression it tends to buckle.

[airnimal]

I am surprised I haven't had my leg pulled of this latest issue. Still you can't make a omelette without breaking eggs!  I have started to put the ironwork on the ends and chamfer the framing. 

The masking tape on the bottom of the headstock is protect the corners of the plastic from being bashed while I struggle with the build. 

 

[Regularity]

53 minutes ago, airnimal said:

I am surprised I haven't had my leg pulled of this latest issue.

Those of us who have scratch built from a paucity of information share you pain.

Everyone else knows better than comment!

[Dave John]

Foreman looks at wagon, cuffs apprentice round the ear and tells him  to hang those doors the other way up. I bet that happened too many times to count. 

 

A lifetime of engineering, I have seen almost everything the wrong way up. My commonest trick is ending up with left hand brake levers since I'm fitting them to an upside wagon. 

 

So Airnimal, if the rest of us that  actually make stuff pulled our own legs every time we made a mistake most of us would would be legless by now.....