Kurt Cobain “Jag-Stang”. Nitro colour coats

The JagStang body ended up with slightly under the planned two days to dry. There’s a gap in the weather, and I need to make the most of it. I’m quickly running out of days before my eye operation, and what I can’t get done beforehand may have to wait for a few months, and who knows where we’ll be by then. It’s now certain that the planned shellac finish on my Natural Ash Jaguar will have to be postponed until later on in the year…

…so it’s full speed on the JagStang.

JagStang – First, light mist coat

Although I’d originally planned to leave the body a full two days for the primer to cure – it’s already fully dry, and there shouldn’t be any problems spraying the colour now. I’ve already rubbed the body down with a 350 grade Mirlon sanding pad, but it’s not a waste of time to visually go over the primed finish just once more. The spray booth is cleaned out and the extract fan switched on well in advance, to establish as clean an airflow as I can manage. The body is hung up, and the hanging hook adjusted, so I can position the body with it’s main faces at a slight angle to the predominant direction of the spray nozzle.

I’m using a Sonic Blue nitro lacquer by manchesterguitartech.co.uk and although I’m hoping to get the body covered with just a single 400ml rattle can – I have a second can, just in case. The can is left out to warm up in the warmth of the morning sun, and I make sure the contents are well mixed by shaking, for at least a minute, before spraying. I’m using a fresh nozzle with a vertical, oval shape, and the first pass is an exceptionally light mist coat – to help the colour settle onto the primer.

JagStang – First, light mist coat

The first mist coat is so fine – it’s hard to actually pick up the colour change at first, and the lacquer “goes off” in just a few minutes. However – the mist coat helps spot any potential problems on the primed surface, and also serves to help establish a “route plan” to coat the body evenly and economically. I’ve worked out a method by which I spray the edges of the body first – letting the spray feather out over the flat surface. By addressing the “front” edges of the body first, and then the “back” edges – all of the the “sides” of the guitar effectively get two coats. It means I have to manually reposition the body with the painting stick a few times, in order to get to the ends especially – but the body can then hang whilst I spray both of the flat faces in turn, and ensure that the larger faces are feathered-in nicely to the overspray from the sides. The first, lighter coats establish and follow the “route plan” – and the spray nozzle is moved quite quickly over the work. Subsequent, thicker coats will be applied with the nozzle moving at a slower rate, and with multiple passes across the body, from slightly different directions.

JagStang – First colour coat

After the first mist coat has had about 15 minutes to dry – I apply the first real colour coat. This follows the established path over the work, and is a single pass with the nozzle moving at a reasonable, constant speed. Enough so that the colour coat ends up looking fairly solid – but not too much as to cause drips or sags. At this stage there are obviously some inconsistencies, and still some primer showing through – but these areas will even out with subsequent coats. The first colour coat is given about 45 minutes to dry, after which the lacquer is reasonably resistant to gentle rubbing, 9if required). If any small fibres or motes of dust are evident – they shouldn’t be trapped under lacquer, and can usually be lightly rubbed, or brushed away. With a light blue coat like this – they’re easy to spot! Any surface contamination can be brushed off, or gently rubbed back with 400 grit paper. After faulting, the affected areas are lightly cleaned over with naptha. Occasionally – particularly stubborn marks – perhaps even runs or sags – may have to be levelled before proceeding. This can best be done with 400 grit paper, using a little more naptha as lubricant. Obviously – there’s only a requirement to remove any blemishes, and at this stage – the risk of rubbing back into the primer shouldn’t be an issue, so long as the approach is cautious.

If any sanding has been done – it’s essential to clean back the work properly, before proceeding with the next coat. Normally – such interventions are only local, but if there’s any risk of sanding dust falling into any of the recesses – it’s best to clean everything out again. A tack-cloth can be handy – but don’t rub too hard on the surface. Many tack-cloths leave a sticky residue which can affect the adhesion of the paint. If any areas do show signs that the paint won’t stick – (usually, you’ll see small, primer-coloured spots as the paint film tightens) – rub the area down to the primer again, and degrease thoroughly with naptha. After cleaning with naptha – always ensure the surface has thoroughly dried, before proceeding with subsequent overcoating.

JagStang – Second colour coat

The second colour coat follows the usual path, but it’s actually two complete passes this time – with the time taken to complete the first pass enough for the paint to key into the existing finish, and then just begin to become touch dry. It’s essential to make sure the surface isn’t touched at all, as the work is manipulated with the painting stick – otherwise the soft surface will drag, and a physical mark will be left.

The nozzle is also moved slightly slower than before, for this pass. By working into a light source, (the work is illuminated by a lamp placed outside of the spray booth – with the light shining through the acrylic screen on the side), I can watch the paint spray land on the body, and gauge the thickness and consistency of the application. An extract fan pulls air from the bottom left of the spray cabinet, and so I aim to almost “float” the paint spray onto the work, carried by the slight air current generated between the extract fan, and the spray can in my right hand.

Once the two passes have been completed – the work hangs for at least an hour, for the latest coats to become touch dry. After that – the work is faulted again, and any necessary rubbing-down and cleaning carried out. The piece is cleaned over once more, and left until any cleaning naptha has fully evaporated.

JagStang – Third colour coat

By now – the 400ml can is getting towards 2/3rds empty, but there should be enough left over to complete a third coat. This is another double pass, and I aim to apply a thicker, much more liquid-looking coat this time. However – this is sometimes tricky when the pressure in the can is dropping off a bit. As the can becomes emptier, I sometimes find there’s a tendency for the nozzle to spit a little more and the spray, when it lands, becomes much more likely to show a “texture”. Much of this spray texture will eventually reduce as the solvents in the paint evaporate, and any “orange peel” texture remaining after the paint has cured, will eventually be buried under clear lacquer and the whole thing flat-sanded – so it’s not much of an issue. At this stage – I’m focusing more on getting a consistent, opaque colour coat. This third coat is all about using up the remaining paint in the tin as evenly as possible across the whole piece, and trying to set the job up, so I can finish off with just one more full, liquid coat from the top of the second can.

Once again – the work is given at least an hour for the latest paint to become touch dry. The finish is faulted, and prepared for a final coat. If any problem areas have been picked off as the process has been carried out – any faults should always be just a single coat deep, and should usually rub back to opaque colour. Once it has been faulted – the whole piece can then be regularised and keyed with a light rub over with a 350 grade Mirlon pad. This should help make sure there aren’t any remaining surface irregularities from sanding, which might show through. Once ready – the piece is cleaned over properly, and then positioned in the booth for the final colour coat.

JagStang – Fourth, and final colour coat

I haven’t had to sort many surface faults during the paint application – and I probably would have been able to cover the body with just the single can of paint. However, since there were one or two slight spits which needed rubbing down after the third coat – here I am with the spare, second can – looking to use the more regular spray to provide the final, definitive colour coat.

This is the thickest, most liquid application I can manage without causing any drips or sags. A double pass helps the paint from the first pass dry before overcoating, and helps keep the paint film from becoming too “runny”. The end result is consistent and even – and it seems so much easier to use a fresh can, rather than the rag end of the first. Once the piece has dried for an hour – I’m getting towards the end of my painting day. Since the surface is clean and appears to be virtually fault-free – I might as well lay the first light clear coat over the top, so I can let everything dry properly overnight with at least a light protection.

JagStang – First, light clear coat (key coat)

A light “key” coat of clear lacquer is applied over the work in a single pass – following the usual route over the piece. The lacquer will partially “burn-in” to the colour coat, and should help future clear lacquer coats build over the top. Once complete – the work is left to hang for an hour whilst the lacquer becomes touch dry. The body is then left to hang in the drying cupboard overnight. Just the clear coating to complete now, before the weekend…

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