East Barnet Joint Stock - a workbench

[Chas Levin]

Next, early this morning, I took the 10% linseed oil mixure from yesterday and tried using it in the bow pen, doing a basic wide panel plus as thin lines as I could underneath it, then adding some sidebars to test how they settled into the main panel. I was trying to juggle too many things at once though, and added the sidebars a little hastily and lumpily, so that part of this test isn't very good.

@MikeTrice, yes, the 10% mix is still perfectly workable 24 hours after mixing; it is more viscous and therefore less prone to overflow from the pen blades and a little less prone to flooding on the workpiece, but still not as tight as the unadulterated stuff. However, the settling - and therefore blending between parts done at different times - is less fast and less complete than when the mixture is fresh (unsurprisingly) so it's a trade-off between flooding and blending!

I think adding oil makes it flow more easily, period, and extra care is needed using the pen, especially when stopping and starting lines, plus the pen needs to move as fast as is practical and controllable, though the enhanced flow characteristics mean there's less tendency for breaks in the line - here's a series of photos from 7 minutes after it went on (no discernible drying at all) to 5.5 hours later (getting to touch-dry, still marking if touched other than very lightly):

 

 

 

 

 

 

[Chas Levin]

Next, I did a mix adding (as near as I could) 6% oil to PPP P752 GNR Dark Green Dull (satin/eggshell). I say 'near as I could' because I accurately measured the 0.25ml oil and added it to a little under 5ml of the paint. The painting was done with a pen, in 17degrees C and as before, here's a series of photos from shortly after the paint went on, with various lines and bars added during the first 20-odd minutes. As in the post above where I tried out the 24 hour old 10% gloss mix, the sidebars here were added a bit hastily because I was trying to juggle the two tests, so the less than perfect blending is mainly down to that I think - I'll do this test again, but without doing anything else at the same time!

Workability was pretty much the same as with the 5% gloss - fine to stay in the pen providing only one drop was added at a time, noticeably more prone to flooding at starts and ends of contact, very thin lines very difficult - fine for infilling though.

What I found most interesting is that the change in the finish during drying from gloss to dull (which only takes a few minutes with the unadulterated paint) is slowed down incredibly here - even 9.5 hours later it's still somewhere between gloss and satin. @Jon4470 - it looks like you were right and the oil does make the satin more glossy! I couldn't take any more photos in daylight but we'll see where it's got to in the morning...

 

 

 

 

 

 

 

 

Edited May 5, 2022 by Chas Levin

[Chas Levin]

First, a quick update on previous mixes - here's the gloss+10% oil mix residue after 48 hours sitting in the pot (I took the photo yesterday) where a thick skin has formed, but still there's still (very thick) liquid beneath:

 

 

Here's the remains of the satin+5-6% oil mix after 48 hours too - not skinning yet but very thick and starting to string and no longer workable in a pen:

 

 

Next, the penned areas done using this satin+5-6% mix 48 hours ago haven't changed noticeably in terms of the degree of gloss (they still look like gloss that's been let down with a little satin) but they've flattened down quite a bit more and the hardening has begin - you can see a couple of marks I made with a nail but it took some force to do so. The two irregular blobs above it are also shown for comparison, they're the unadulterated satin (left) and gloss (right) from earlier tests:

 

 

I came to the conclusion that I've been applying far too thick coats and that I need to set the pen blade gap as thin as I can, move the pen faster and do everything possible to achieve the thinnest coat I can, because you can see that thicker areas don't settle to the same level as thinner ones, not to mention what are shaping up to be truly epic full curing times! So this morning, I mixed a fresh batch of satin (dull) at 5% (rather than the nearer 6% of the first batch) and did a couple of rectangles, taking far more care over the film thickness. I also waited a few minutes before adding each side of the shape and joining it to the previous side, in order to replicate what will happen on the model, where I'll be moving it round and re-positioning the pen to do different bits; each side was done with the same loading of the pen though:

 

 

Twenty minutes later I added another similar rectangle (to the left of the first in the picture below), done the same way and still using the same paint from the first loading of the pen - which in itself shows how adding the oil prolongs the workability of the paint because usually, I wouldn't be able to continue using paint loaded into the pen after as long as twenty minutes:

 

 

And here's how the two rectangles looked nearly an hour after doing the first one - I think it's pretty clear that the coat thickness is another key factor as these two are both starting to dry a lot faster than my previous oil-mixed tests, but crucially the blending in of the four corners is still working very well indeed:

 

[N15class]

You have more patience than I do.  Very interesting work though.

[Chas Levin]

It does take some patience, that's for sure Peter, but it becomes more fascinating the more I follow the thread, if you know what I mean. The more I learn, the more I wonder...

It occurred to me today that I might be adding more oil than is needed: I went with 5% partly because of seeing references to a 5% thinners mix and partly because the scale-marked pipettes I found start at 0.25ml and the measuring cups start at 5ml... so everything seemed to suggest it.

10% is definitely too much I think - it makes the paint far too runny - but I'm going to try 3.3% (0.25ml oil into 7.5ml of paint) before getting down to the practice panels, because if 3.3% works just as well it might leave the paint a little thicker and also allow it to cure and harden a little quicker.

The 5% mix is only just manageable in terms of flooding and keeping the coat thin, so I wouldn't want to use that on the model and perhaps have it affect the final look, only for someone who's done this before to reply to my initial question on here and on Western Thunder about recommended amounts of oil and say that 5% is way too much!

Here's a last look for today, this is the pair of 5% satin rectangles I did this morning, after 9 hours:

 

Edited May 7, 2022 by Chas Levin

[Chas Levin]

So, to the (hopefully) final fourth test mix - 'The Fourth Pigment', if Frederick Forsyth were to write about it.

Or, if your taste is more towards John Le Carré, 'The paint that came in from the cold'!

Or... 'Tinker, Tailor, Slower, Dry'?! 😆

Ok, sorry about that, back to watching paint dry...

 

This test was designed to check that I hadn't been over-doing it by adding as much as 5% linseed oil. I therefore used the scaled pipette to add 0.25ml to 7.5ml of PPP P752 GNR satin, in about 17-18 degrees C. I took care to put down as thin a coat as possible with the bow pen and, as in the previous test, I waited a minute or two before adding each new side to simulate what will happen when doing the actual model - here's a photo shortly after completing the rectangle:

 

 

And here's a photo after 5 minutes and the paint is already starting to dry in the thinnest coated areas, which is I think due partly to the thin coat, partly to the 17-18 degrees ambient temperature and partly to the fact the 3.3% oil isn't quite enough to slow down the drying very much:

 

 

Here's a photo after 12 minutes, shortly after I'd added some bars, running between the two long sides, to see whether they'd blent in or not. I was unable to get the first loading of the pen to flow easily and quickly, so I reloaded from the mixing pot:

 

 

Here's the state of play after half an hour and it's clear that the drying is proceeding much more quickly than the 5% mix:

 

 

Also, the finish is noticeably duller than the 5% mix - here's a closeup taken a little while later of part of today's 3.3% test next to part of the previous and visibly glossier 5% one:

 

 

And finally, here's a photo of the 3.3% mix after 8 hours drying time:

 

 

I'll keep an eye on the various tests over the coming days (or even perhaps weeks) to check how they're curing and hardening. Adding the oil certainly slows down that process, but I have to assume the paint does eventually harden and fully cure as normal, otherwise I imagine no-one would suggest doing this at all.

 

So, my conclusions? Based on the 5% and 10% gloss mixes, the two 5% satin mixes and the 3.3% satin mix, I think 5% is the optimum amount of linseed oil to add, as it gives a compromise between lengthening the drying time (and therefore allowing separately applied areas to blend at the edges) without making the paint too runny and causing flooding.

 

Having decided that, the next job is to apply narrow dark green lines (using unadulterated paint) alongside the outer white lining already in place on the C2's bunker and side tanks, then a little more practice with the 5% mixes and then the dark green infills... at last!

[N15class]

I assume that it does too, I remember remember reading somewhere, that in the day coaches were stored for quite sometime after varnishing as it took a while to cure. I would image varnish was mostly linseed, with white spirit and a curing agent.

[Chas Levin]

Nice point, thanks Peter: I might read up a bit on LNER carriage finishing specs from back then - I think at least one of the Harris books goes into considerable detail about that, including varnish recipes and drying times.

And they're lovely books to look through anyway...

[Chas Levin]

Checking up on the curing process, the results show the crucial importance of the thickness of paint applied in determining how long the drying, curing and hardening process will take, particularly with oil having been added so that the drying time is already being prolonged.

 

The areas painted with the 3% satin mix only two days ago and the those done the preceding day to that with the second 5% satin mix are already impervious to marking by finger-nail, and feel almost as hard as those done previously with unadulterated paint. So, if the coat is thin enough, a 5% oil-thinned satin will be fully touch-dry and considerably hardened in only a few days, though clearly the full curing and hardening is going to take at least a couple of weeks, going by what I've read in Ian Rathbone's and Bob Shepherd's books.

 

However, the first 5-6% satin mix from last Thursday is not quite as hardened yet and will show very slight marking - it also still feels ever so slightly soft. The difference between them is that this one was applied in a very thick coat as I was quite unprepared for the increased liquidity of the oil-thinned paint, whereas with the later mixes I kept the coat much thinner.

 

The earliest gloss 5% mix from last Wednesday is likewise not fully hardened, while bringing up the rear is the 10% gloss mix  - also from last Thursday - which is most certainly fully touch-dry but still slightly soft beneath the surface and still able to be marked. This was probably the thickest coat of any of the tests and it had the highest amount of oil, also a strong factor.

 

The remains of the various mixes in the pots are also showing the same behaviour, whereby they eventually skin over, with an increasingly thick skin, but the residue beneath stays liquid - even if it's a very thick liquid - for a long time.

Presumably, once a thick skin forms, it inhibits the evaporation of more solvent and slows down the whole process a great deal, whereas with a thin enough coat, the entire coat effectively forms that first skin, the solvent carrier all evaporates in one go and the oxidising and hardening can start straight away.

[Chas Levin]

I haven't been able to do anything on the painting front for a few days (beyond noting the continuing hardening of the various linseed oiled tests) but I did do a little more on the Slaters ex-NER Birdcage Brake that has been languishing on my modelling tray for far too long. One side's solebar-springs-axleboxes assembly was put in place:

 

 

I slipped a piece of thickish paper in between the solebar and the inside of the van side, in order to hold the solebar assembly perpendicular against the locating ribs on the underframe. I then had to (gently) dig it out again: why it didn't occur to me to use a much wider piece of paper so that it could be pulled out easily, I cannot say...

 

I also cut one of the stepboards from its sprue - fiddly to do without breaking or straining the very thin plastic! Still some cleaning up to do:

 

[Rob Pulham]

I suspect that they will also need careful handling to avoid damage in use.

 

In 7mm I replace them with brass rod and odd leg milled brass angle to hopefully reduce the risk of damage.

[Chas Levin]

Yep, I'm sure you're right Rob. I think I'll make up some brass wire strengtheners to glue discreetly behind the vertical struts, going up into the body, for a little extra support.

 

As Eric Morecambe so memorably said: "Thank you for your support - I'll wear it always!"

Edited May 11, 2022 by Chas Levin

[Chas Levin]

A quick paint+linseed oil-drying update:

 

The various 5% and 3% thin coats now appear to be as hard and resistant to marking as the unadulterated paint usually is. The loss of the satin or dull finish hasn't changed though - they appear to dry somewhere towards the gloss end of the satin-to-gloss spectrum; not a problem if you're varnishing afterwards and can thereby control the degree of gloss or otherwise, but something to bear in mind if not.

 

The 10% mixes (thicker coats) are still not quite there and can mark, though only lightly, even though they were done nearly 10 days ago.

[Chas Levin]

Practice continues with 5% oil-diluted panel filling, but I thought I'd better get going again on the actual model, by doing the thin dark green lines adjacent to the outer white lines, to mark the boundary of the dark green. I think as a system it's a compromise, because under close scrutiny I think those thin green lines will be visible alongside the wider penned areas, but there's no denying they will form a boundary between dark green and white. And at normal viewing distance, under varnish, they'll hopefully not stand out.

Each line calls for some time spent before actually painting, working out how best to position the model and the ruler - this very small but very thick ruler has worked well for lining so far and the two rubber pads stuck underneath allow it to straddle things like buffer housings very well:

 

 

 

Applying these lines calls for accuracy and concentration, because if you go over the white, trying to remove it with the spirit-dampened brush is very tricky - the green pigment spreads appallingly visibly over the white! You can remove it quite successfully sometimes, by sweeping off the white and across the green and never the other way, and by cleaning the brush after every single touch, even when nothing visible has apparently been done.

Here's the work so far - it's not very easy to see because it blends in with the dark green 'wash coat' - just the bunker rear and in spite of my best efforts, there will need to be some touching in of the white in a few places. This - and the side tank fronts - are far more awkward to do than that tank sides, partly because of the difficulty of holding the model in such a way as to facilitate easy access and partly because of the various things - buffer housings, vac pipe, lamp irons, handrails - in the way:

 

 

Once the rest of this stage has been done, it'll be filling in time at last. I'm considering the best order in which to do each area of the dark green filling in - inclining towards doing the long horizontals first, then vertical bars, tank fronts last. The front corners of the side tanks are where I think poorly blended areas will be most conspicuous. The bunker I realised can be done in two halves, each consisting of one side plus one half of the rear, up to the upper lamp iron and the vac standpipe, both of which form a break in the lines.

Edited to note that what appears to be a small white spot close to the lower left hand corner of the buffer beam isn't in fact a rogue spot of white paint, it's an odd trick of the light. There is a small round raised area there, that appeared at some point during the application of the (many) coats of red. I decided at the time to leave it, rather than risk damaging the surface and in real life - it looks not unlike a rivet on the buffer beam but part of the same red finish: somehow, it's caught the light in the photo above and looks white...

Edited May 15, 2022 by Chas Levin

[Chas Levin]

@Jol Wilkinson, Jol, I bought a couple of signwriting brushes as you suggested and gave one a try:

 

 

They do a terrific job and hold a lot more paint, but the areas to be filled here are very small - or 'narrow' is perhaps a better word - and I'm not finding it possible to control the long bristles or the paint film thickness as well as with the bow pen in such small spaces. I realise of course that may be partly - or largely - due to my being a complete novice with these brushes whereas I'm reasonably confident now with the pen.

Very interesting to use though, thank you for the suggestion: I'll find something to use one on in due course, another tool in the armoury.

[Chas Levin]

I've now completed the thin dark green lines all the way round the outer white lining on the whole loco - the three sides of the bunker and the four surfaces of the two side tanks. Here's a photo, though the lines are so thin and the first thin coat of the dark green provides so little contrast that it's difficult to see the work:

 

 

I have solved one question though, concerning the way some lines seem to change their appearance depending on the angle of view and the lighting conditions.

Hopefully you can see in the picture above that there are a few small stretches of the outer white lines - the section that runs below the steam dome for instance - which appear to have 'bulges'? These are completely absent in real life, looking closely at the lines under good lighting and magnification, so what's happening in photos like this?

Well... those apparent bulges are in fact light reflections on the slightly domed sides of the middle black line! Because the black is very shiny gloss, light catches it and makes it look white and it then appears to join the white line alongside it... Took me a while to work that one out🙄. Hopefully the final varnish will tone that effect down.

 

Back on message so to speak, here's another photo where you can see the thin dark green lines I've been doing:

 

 

I'll give them a few days to harden - using the time to get in some more practice with my 5%-oil-thinned paint mix - before doing the filling in of the dark green areas for the final time. Not having to worry about going onto the white will make the job considerably easier, even if it's at the cost of that thin dark green edging remaining visible, something else that I hope the varnishing stage will help to hide...

 

Edited: I hadn't seen how prominent that slightly raised section of the dark green edging on that front upper curve looked until I saw this photo, so I've just corrected it - still not perfect, but better!

Edited May 24, 2022 by Chas Levin

[Chas Levin]

Finally - finally! - I bit the bullet and started doing the dark green infill, the bunker first:

 

 

 

 

 

And here's a shot with the light at an angle, to show the finish:

 

 

I've found doing this part by far the most difficult - there's a lot to take care of all at the same time!

As well as making sure the paint only goes where it's supposed to (no small thing!) you also have to keep the wet edge going, make sure the oil-thinned paint isn't leaking out of the side of the bow pen, keep the pen moving sufficiently fast that the paint film is thin and even, join intersecting parts only enough to let them flow together but not overlap so that a raised area forms where the coat is double thickness, plus the model has to be re-positioned halfway through (flat for the side, on edge in the vice for the rear) and everything has to be done as quickly as possible, because even with the 5% linseed oil added, it all needs to be on within a few minutes so that it settles together.

I considered several different orders for doing the various areas and had decided to do the horizonals first and then fill in between them, but keeping that wet edge is so crucial that in the end I went round each section's consecutive sides in order, so that there was only one wet edge at a time; I left the areas around the handrails until last though, because you can't do everything at once and I reasoned that the handrails would hide any poorer joins. I did the corners on the second side by running the pen along the ruler too where possible, even though they're such small areas, because it's easier that way to keep the pen moving at the same speed as for the longer stretches and keep the paint film uniform: I'd tried doing the corners freehand the first time and it left slightly thicker paint in one or two small areas, though it's pretty unobtrusive.

 

I also found that because the paint is less viscous through adding the oil and flows very easily, you can hold the pen at a much wider range of angles. As you're laying each line against the last one, capillary action also helps draw out the paint, so I was able to get the pen right under the handrails - while still using them as a straight edge - where I'd anticipated having to fill in with a brush. I also realised - just as I was about to do the first line up against the side beading - that the beading and the footplate are there as ready-made straight edges! I'd got so used to use the ruler, I almost missed that:

 

 

I kept the wet edge along the corner - and just over it - wet by drawing another line against it in between doing other parts, so that when I went back to fill in the final vertical, it was still wet:

 

 

Very pleased to have got the first part of this done: I'd got to a point of having practised, tested, researched and rehearsed so much that it had made me quite nervous and in the end, I just had to plunge in.

Unfortunately, because the weather's getting warmer, it also meant getting up at five in the morning, consuming two cups of strong coffee and a medium sized cooked breakfast and getting painting - with the window wide open - by six! 🙂

[Rob Pulham]

I know what you mean about the procrastination Chaz. It's very easy to build things up out of all proportion so that when you actually pluck up the courage and get on with it, they don't seem half as daunting as they did in your head.

 

You must be really pleased with progress so far, it looks superb.

[Chas Levin]

11 hours ago, Rob Pulham said:

I know what you mean about the procrastination Chaz. It's very easy to build things up out of all proportion so that when you actually pluck up the courage and get on with it, they don't seem half as daunting as they did in your head.

 

You must be really pleased with progress so far, it looks superb.

Thanks Rob, I am pleased, even more so since having done both side tanks' dark green infills yesterday morning and this morning too (photos to follow). Four consecutive days of getting up at five and painting by six and I want a lie-in... tomorrow... maybe even until seven! 😃

 

I'm normally better these days at avoiding procrastination and 'mental stiction', but I couldn't help feeling there was a lot at stake here - messing this part up, having done so much work on it already (and with those white lines sitting vulnerably next to the dark green areas) would have been extremely frustrating. Unavoidable in the latter stages of a complex project of course, but I haven't built anything else that's taken this long or had this much detailed work, so I haven't been as conscious of it before and it really did take some determination to pick the pen this time! As you say though Rob, it's a mental mountain that just disappears when you actually do the job.

 

I've noticed another tendency in my work habits, which I'm calling First Date Syndrome. If I'm going to do a new or difficult thing over several areas (like this dark green infill) I used to assume that the first efforts would be less good and that the second or third would be much better, once I'd got into my stride or warmed up or whatever happens. But lately, I've found that it's the first try that comes out best, because I'm totally focussed, making the fullest effort, leaving nothing to chance and so forth - a bit like that first date, where you dress carefully, watch what you say and use the right cutlery! After that, the next go is often a little less good, I think because I relax a little (like that second date that doesn't lead to a third!). So where I used to begin with less prominent areas, I've taken to starting with the most important area, taking advantage of how primed and focussed I am and it seems to be working well so far.

I'm also making a point of giving myself a quick pep-talk after the first go, to remind myself to maintain the high level of concentration and not to get cocky and that's working well too - all four of the dark green areas are pretty similar in their finish (the two side tanks and the two halves of the bunker - it's divided in the middle by the top lamp iron and the vac pipe). By no means perfect (the underlying surface wasn't, to start with) but pretty good. The crucial importance of the best possible finish at each stage (because of how that affects the next layer) is another thing I've learnt on this project!

 

Sorry - long waffle - but yes, very pleased, glad you like it too and thank you to all for the likes!

Edited June 4, 2022 by Chas Levin

[Chas Levin]

Here are some photos of the dark green infill on the side tanks - again, very pleased this is done, as it wasn't easy:

 

 

 

 

 

 

 

 

In this last shot - showing the light reflecting off the finish - you can clearly see that I now have satin (or near-matt) central light green areas, surrounded by gloss lining! I had been thinking about flatting down those gloss areas to match, but it then occcurred to me that as I'll be putting transfers into those light green panels, it would be more sensible to give them a coat of Klear, so that they would more closely match the gloss of the lined areas, apply the transfers and afterwards apply satin varnish over the whole lot!

 

Doing the fronts of the side tanks called for some care: with the loco mounted on the stand and in the vise facing upwards, there's no way to position a ruler to do the few lines needed for the tanks' front faces, so I had to wing it, holding a square section piece of wood - actually a large firelighter matchstick I had to hand:

 

 

I'm holding the left-hand end of the wood with my left hand, but the right-hand end is free, resting upwards against the underside of my thumb. I got away with it because the parallel touching lines you do for infills like this don't have to be terrifically accurate, providing they flow well and settle together into one coat. Next time I do something like this though, I'll work out a better way to do it!

[Jon4470]

Chas

 

i haven’t dared to comment earlier in case I jinxed things!

 

The lining looks fantastic - you’ve achieved a beautiful and neat finish!

 

Jon

[Chas Levin]

7 hours ago, Jon4470 said:

Chas

 

i haven’t dared to comment earlier in case I jinxed things!

 

The lining looks fantastic - you’ve achieved a beautiful and neat finish!

 

Jon

Haha - thanks Jon, I appreciate the sentiment, though I'm sure you wouldn't have done! 🙂

 

It's pretty much there now as far as the lining goes, just the red along the valance to do, plus some touching in of white where the dark green as gone onto it, really tiny amounts in equally tiny areas, but worth attending to nevertheless.

 

Do you see what I meant about the depth of colour of the dark green now it's been applied with the pen, as opposed to when it was a rather scrappy brushed first coat? I remember you saying that first coat made the true GNR colour scheme start to show through and I said wait until it's been done as a thicker, denser coat. With hindsight of course I'd not have bothered with that first brushed coat - and won't on future GNR locos - but I hadn't learned about filling in areas using the pen at that point. Ian R does mention it in his book, but quite briefly and I'd failed to spot it and didn't think of doing it on this model until he advised doing so on the WT forum.

[Jon4470]

16 hours ago, Chas Levin said:

 

 

Do you see what I meant about the depth of colour of the dark green now it's been applied with the pen, as opposed to when it was a rather scrappy brushed first coat? I remember you saying that first coat made the true GNR colour scheme start to show through and I said wait until it's been done as a thicker, denser coat. 

 

I can certainly see the depth of the green colour now.

 

I think it will interesting to see the effect that overall gloss varnish creates. I have a feeling it will make a difference......... And then when you add the transfers another change in the perception of the colours could well happen. Whatever does happen, though, I’m sure the loco will look (even more) fantastic.

 

Jon

[Chas Levin]

12 hours ago, Jon4470 said:

 

I can certainly see the depth of the green colour now.

 

I think it will interesting to see the effect that overall gloss varnish creates. I have a feeling it will make a difference......... And then when you add the transfers another change in the perception of the colours could well happen. Whatever does happen, though, I’m sure the loco will look (even more) fantastic.

 

Jon

Thanks Jon; yes, each change brings other effects, doesn't it? I noticed when taking the latest photos that the dark green (which has some blue in, as I know from cleaning the brushes and pen) is making the light green look 'cooler' in many of the photos.

At least the really awkward work is behind me now and it should be a clear run from here!

Thank you Jon and all those who've been so encouraging and helpful👋.

[Chas Levin]

The cab doors are now dark green (which looks quite prominent but I think that's partly because of the recent discussion about it) and I've also done the red lining along the valances, using the Kern compass bow pen (and I am going to try to use the correct terminology for the other, non-compass type of pen which is not correctly called a bow pen at all, but which should be called a ruling or drawing pen). Here are some photos - the ones of the model lying on the grey desk mat show the colour more realistically as it is in real life, a warmer colour:

 

 

 

 

 

 

 

The closed cab door was done with the Haff 135 ruling pen, but it took three goes: I thought the first one had gone very well, a nice thin even coat but as it dried, I realised that there had been a tiny gap between part of two of the touching lines and a slightly lighter strip began to be visible, where the lighter green undercoat was showing through. I decided to risk doing another coat on top but did it too hastily, with several of the lines not really touching, so it started drying with vertical ridges; had I been trying to replicate a wooden door made from vertical planks it would have looked superb, but for sheet metal, not so good! Fortunately I realised in time and was able to remove the double coat with white spirit and do a third one, carefully and properly.

The open cab door I had to brush because there isn't room for a pen, but it's an awkward fit for a brush too, so I decided to try using Phoenix Precision Varnish Thinners in the paint. I'd done a first coat, brushed, with unthinned paint and got similar patchy coverage to when I did the first coat on the dark green areas of the bunker and side tanks, so having learned from PPP's book that varnish thinners are designed to dry more slowly to give the varnish more time to settle out into a flat film and having ascertained in talking to PPP on the phone that you can use that type of thinners with paint, I did a second coat using a wide flat brush, thinning the paint quite a bit with the PPP PQ10 Varnish Thinners and with the loco in the stand held vertically pointing upwards.

The valance lining is nice and even, straight and a good consistency but predictably over scale thickness - but there's still the black edging to put in, so I'll be able to thin the red a little at that stage.

The cab doors also need the top beading doing in black, then there some of the bunker and side tank white lining to re-touch but I'm not hurrying to do that, as the longer the dark green areas have to harden the better.