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Mick Bonwick

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  1. Mick Bonwick

    D3721. Step 14.

    By Mick Bonwick,

    Holiday over and back to work.
     
    The airbrush has been loaded with a small quantity of AK Interactive Engine Oil in order to replicate the oily residue at the bottom of the filters. I have masked off the underframe while doing the filter area, just a piece of card laid against the running plate. Only a very small area has been thus affected on this particular locomotive.
     


  2. Mick Bonwick
    Once all of the panel line wash has been applied and allowed to dry completely (24 hours), it's time to start airbrush work on the body. Using the same Railmatch frame dirt as before, but mixing it with a little Railmatch weathered black, a very light misting is applied to the whole locomotive. Side, ends, top and underparts. This is deliberately not perfectly even, more being applied in some places than in others, because I don't want the end result to look as if it has had a perfectly even coat of paint airbrushed onto it.
     

     

     
    You can see by looking at the roof in particular, that this process has added a dusty texture to the paintwork. Care has to be taken not to overdo this in 4mm work and below, but from 7mm upwards it becomes more necessary.
     
    There will be a break in this blog for a week or so, while I spend a week at Missenden Abbey Railway Modellers' Summer Retreat and get on with some . . . . er . . . . . . weathering.
  3. Mick Bonwick
    The next step is to randomly remove some of the paint to portray a buildup of grime around things like coupling hook, bolt heads and pipe connectors. This is achieved by using a slightly damp brush, and by that I mean a couple of drops of thinner placed on the bristles rather than dipping the brush into the thinners. The brush is then used in a stabbing motion, rather than a stroking motion, to slowly and gently remove the paint. If it all comes off straight away, your brush is too wet!
     

     
    Another method is to use a cotton swab that is damp and perform the same actions, although this will inevitably leave some cotton strands about, and you'll forget to blow them off before taking a photograph . . . . . . .
     

  4. Mick Bonwick
    Buffer beams get very dirty, even on slow moving stock, so this needs to be portrayed on a model for it to look right. This build-up of grime is portrayed by several coats of (in this case) frame dirt, added a little at a time and manipulated before it gets too dry. These photographs show the first coat to be applied - just a thin application that barely shows up.
     

     

  5. Mick Bonwick

    D3721. Step 9.

    By Mick Bonwick,

    The locomotive has been removed from the cradle and further light coats of frame dirt applied. The next task is to spray from above the chassis components to cover areas inevitably missed while it was upside down - particularly the steps, axleboxes and sandboxes. There is some overspray, but that will all help to make the bodysides and running plate look grimy once the next steps are completed . . . . . .
     


     

  6. Mick Bonwick

    D3721. Step 8.

    By Mick Bonwick,

    The frame dirt has now been airbrushed onto the frames as well, taking some care not to get overspray onto the body. This is not critical, but it helps to keep extra work to a minimum if I decide to spray the bodywork a significantly different shade of filth. With the locomotive upside down in the cradle, it is quite easy to ensure that the underneath of the running plate is covered. The accuracy of the airbrush also helps to keep unwanted paint off the wheel treads.
     

  7. Mick Bonwick

    D3721. Step 7.

    By Mick Bonwick,

    Clean wheels.
     
    With the aforementioned battery applied to a pair of wheels, a cotton bud soaked in isopropyl alcohol has been applied to the wheel treads and the backs of the wheels. You should be able to see that all of the dried enamel paint has been completely removed from those surfaces that need to be clean for conducting electricity. Isopropyl alcohol will remove all enamel and acrylic paints from these surfaces, so you will need to take care with where you apply it.
     

  8. Mick Bonwick

    D3721. Step 6.

    By Mick Bonwick,

    Round to the other side of the chassis now. Same process, but you can see where the last rotation of the wheel has yet to be sprayed. Still no masking, and the small spray area resulting from coming up close has kept the overspray off of most of the frames. Turning the wheels with the battery is still keeping the backs of the wheels clear because the wiping action of the pickups is removing the still wet paint.
     

  9. Mick Bonwick

    D3721. Step 5.

    By Mick Bonwick,

    The first few coats of paint have been applied. Each coat consists of a pass across the chassis to apply a very light coat of paint. This only results in a very slight discolouration of the wheels, or at least those parts of the wheels that show above the frames. The wheels are then turned a quarter of a turn using the battery and the exercise is repeated.
     
    You can see in the accompanying picture that there is still one small area on each wheel that needs to be covered. You can also see that although there has been some overspray, it is only covering those areas that would be as dirty as the wheels. Notice also that the turning of the wheels while the paint is still wet has kept the pickup-wiped rear surfaces of the wheels clear of paint. No attempt has been made to keep paint off the wheel treads.
     

  10. Mick Bonwick
    Getting tools prepared. As already mentioned, the airbrush to be used is an Iwata HP SB Plus, with a 0.2mm nozzle for fine control when working close up. I'll be utilising this airbrush's ability to come in close and only cover small areas at a time.
     
    The glass dish contains clean white spirit, as does the plastic bottle to the left. The former is used during the mixing of paint to achieve the necessary consistency and the latter will be used to keep the internals of the airbrush clean during the spraying session.
     

  11. Mick Bonwick
    For this project I have chosen to use Railmatch Frame Dirt on the underparts. This is not my usual colour for working on underframes, but I had some available so thought I'd give it a go. The airbrush I am using in this case is an Iwata HP SB Plus, because it gives me a great deal of control over the area to be covered for each pass along the model.
     
    When working on the whole length of a model, whether it is the chassis, bodysides or the roof, I like to have complete control over the area to be covered rather than just blasting away and then cleaning up afterwards. The two main ways of achieving this control are masking and distance from the subject. In this case I'll be carefully positioning the airbrush before pressing the trigger to ensure I only cover the wheels, brake gear and, probably, the lower edges of the frames.
     
    I won't be doing any masking.
     


  13. Mick Bonwick
    There will be some weathering powders (pigments) applied to 'Westminster'  at a later stage, so some preparation is being done to ensure that the particles stay put once applied. My preferred medium is Testor's Dullcote, so off we go. . . . . . 
     
    I'm protecting the underframe in this particular instance, mainly because the detail there will be highlighted using an airbrush and enamel paint, to which pigments 'stick' well enough without help. I've shown the components inside the spray booth because it's warmer indoors for taking photographs. The actual spraying was done outside.
     

     
     
    It doesn't need much of a blast from the aerosol to cover the model, and it dries very quickly - these two photographs were taken 4 minutes apart:
     

  14. Mick Bonwick
    The recent crop of Peckett locomotives from Hornby has lured me back into collecting habits. Temporarily! 
     
    Their reproduction of the Associated Portland Cement Manufacturers (APCM) locomotive, 'Westminster', which ended its days at Kidlington (Shipton-on-Cherwell) cement works (https://www.google.co.uk/maps/@51.8539534,-1.3086071,1896m/data=!3m1!1e3?hl=en), proved too much of a challenge for me and one was purchased specifically for the purpose of describing how it was to be weathered, in great detail.
     
    Thorough investigation of the model revealed that there was significant work to be done before any weathering materials got anywhere near it. The grease that is applied to the model during manufacturing appears to have been applied using a dessert spoon. The result is that it gets everyhere that it is meant to, certainly, but also to many places where it is neither needed nor welcome.
     
    Here is how it appears when viewed from underneath the chassis:
     

     
    Here you can see how there has been too much applied to the motion:
     
     
     
     
    If this excess is not removed then there will be disappointment ahead! The stuff is thixotropic, and once it meets rubbing surfaces will spread everywhere that it can. This means body interiors where it is spread by centrifugal force from rotating mechanisms, and bodywork component joins where it is spread by capillary action through all your carefully applied pigments and washes. It has to be removed.
     

     
    This is just the beginning - the whole chassis will have to be dismantled and drastic action taken. . . . . . . . . . . 
     
     
  15. Mick Bonwick

    A Few More Pecketts

    By Mick Bonwick,

    One heavy and one light weathering exercise for each of Hornby's Peckett 0-6-0ST models.
     
    Nothing more complicated than Railmatch Frame Dirt, Railmatch Weathered Black from the airbrush. Testor's Dullcote to prepare the upper parts for pigments, then Ammo Dark Earth and AK Interactive Black. Some Lifecolor Ash pigment and some Mig Productions Rubbel (sic) Dust for variety and some additional shading with MIG Productions Dark Wash. Oh, and some Gordon Edgar photographs for inspiration a-plenty.
     

     


     
     
  17. Mick Bonwick
    To finish things off, some Black Smoke has been added to the wheel centres and the tender axleboxes and springs. I have also applied some Dark Mud to the seams in the tender, to indicate the start of rust, and some Rubbel Dust to the horizontal surfaces of some of the steps.
     
    The requirement was for a very grubby workhorse, which might suggest that piles of paint and pigments are to be applied, but it is just as effective to apply small amounts of both to achieve the effect, adding more if really necessary at any stage. The principle of only using small quantities at any time to achieve dirty effects is illustrated in many of the images in my flickr photostream:
     
    https://www.flickr.com/photos/laughinglobster/
     
    That's it for now. I expect there will be more after the Great Electric Train Show at Stadium MK. . . . . . . . . . . . . . 
     

  18. Mick Bonwick
    More work with pigments now, to add to the random dirty bits that have been created with Black Smoke. I normally use MIG Productions Industrial City Dirt or Rubbel Dust (that's what it says on the jar) for lighter stains, like ash and sand, and Dark Mud and Track Brown for rusty bits. In this case it will be Rubbel Dust (ash and sand) and Dark Mud (rust).
     
    The lighter colour represents ash staining under the smokebox door and sand staining around the sandbox fillers, and the darker colour is applied to seams in the tender and then brushed outwards from there in random directions. The aim in both cases is to just hint at discolouration rather than have large deposits of different colours, and this is effected by using very small quantities (heard that before?) and brushing them out until the effect is achieved.
     
     

  19. Mick Bonwick
    There are several areas on a steam locomotive where dirt buildup is of a very dark nature. The smokebox, the cab roof, the coal space, the running plate and so on. I like to represent this with a brushed pigment (in this case, MIG Productions Black Smoke) rather than with airbrushed paint. The pigment is applied with a filbert brush and is taken on the brush from the lid of the container, because there is (nearly) always a thin film there consisting of the finest particles.
     

     
    The pigment is added to the model a small quantity at a time and gently brushed out in the direction of either airflow or water flow, depending on area. In this next photograph, the smokebox and the cab roof have been treated.
     

     
    Finally, you may just be able to see that some of the pigment has been placed on the running plate in random places. Further pigment applications will be done to the running plate, but with different colours.
     

  20. Mick Bonwick
    The upper surfaces of this steam locomotive are shown with a heavy layer of soot-based grime. This is achieved by adding more weathered black to the mixture with frame dirt. If you look at the attached photograph you will see the difference between the wheels and the cab roof, for example, but I doubt (hope?) that you will see the join. By gradually changing the proportion of black and brown in the mixture, as work progresses upwards, the chance of 'tiger stripes' is significantly reduced.
     
    Once the dark mixture is applied the brushing downwards process begins yet again. One obstacle around the boiler is the handrail, which prevents a smooth movement from the top to the bottom of the curve. I almost overcome this by pushing the brush bristles down into the gap 'twixt rail and boiler and dragging upwards before starting at the top and dragging downwards. This method is then repeated from the handrail downwards. Not perfect, but it does produce random streaking and uneven patches.
     
    The dark mix is also applied to the top of the tender in preparation for the rust and water that are to follow, being careful to avoid the real coal that has been placed therein.
     
     

  21. Mick Bonwick
    The next step was a repeat of the previous, really, but I have deliberately posted separately to illustrate the difference that one light coat can make once manipulated. The process is the same - a light airbrushed coat from one end of the locomotive to the other, followed by a vertical brushing with a dry flat shader. It is possible that the paint has dried too quickly for this to have an effect, so there is a process that can address that. The flat shader can be slightly dampened by adding a couple of drops of white spirit to the bristles. This is not done by dipping the bristles in white spirit, but by using a disposable pipette (or similar device) to add a couple of drops and then briefly work the bristles in a circular motion on a paper towel.
     
    The damp brush method can be used at any time during weathering to manipulate small amounts of paint, and it works just as well with acrylics as with enamels. You have to be much quicker with acrylics, though, because of the faster drying.
     
    With any luck you should be able to see how the manipulation of thin layers starts to have an effect on the airbrushed surface:
     
     

  22. Mick Bonwick
    The aibrush now turns to the sides of the locomotive and has been loaded with a mix of frame dirt and weathered black. The former is prominent - only a small amount of the latter has been added to the mix. A very light coat has been sprayed along the bodywork and immediately manipulated by brushing downwards with a dry 1/2" flat shader. The paint was drying fairly quickly and the use of a dry brush moved it downwards inconsistently. The result is a deliberately uneven layer of dirt.
     
     

  23. Mick Bonwick
    When the driving wheels were being airbrushed, the paint was being applied to the complete underframe on each pass of the airbrush. Spraying started off the left hand end of the model and continued along the whole length, not stopping until the airbrush had passed the other end of the model. This produced a relatively even coat of dirt everywhere under the running plate. In later stages this evenness will be disrupted by other materials and effects that are intended to show the differing shades and textures present on the real thing, coming from differing sources and influences.
     
    You can see where there is some overspray on the side of the tender and cabside where I made no attempt to protect the original paintwork. This approach was taken because I knew that there would be more paint to add and the overspray would act as a 'base coat'.
     
     

  24. Mick Bonwick
    Underframe dirt is being represented by Railmatch Frame Dirt, variously altered in shade with random additions of Railmatch Weathered Black. It is applied by airbrush in very thin coats, turning the driving wheels a quarter of a turn between coats. This allows the complete wheels to be dirtied without leaving a paint-less shadow behind rods, motion and other necessary gubbins. When it comes to areas behind the wheels (frames, ashpan, springs and so on) then the airbrush will need to be carefully angled to get the paint into the right areas, possibly over several applications. The most important aspect of this process is to keep the amount of paint deposited from each pass to an absolute minimum, almost to the point of not seeing any difference.
     
    You may be able to see what I mean from this sequence. Sorry about the blurred one - my hands aren't as steady as they once were!
     
     




  25. Mick Bonwick
    Work will start with the underframe and to facilitate this I have used a scrap piece of protective foam channel and inverted the locomotive into it. Like the vast majority of materials and methods I use this is not a Bonwick original idea. The idea came from Tim Shackleton (who may well have copied it from somebody else) and the channel came from Gilbert of this parish (who may well have liberated it from a skip) as a free gift at a Missenden weekend session.
     
    While the inversion is in effect the wheels can be freely turned by the use of either a 9v battery or a favourite power supply and a couple of fly leads. In this case I want to turn the wheels slowly so a Gaugemaster DC controller will be used.
     
    The enamel paint will be stirred extensively using the Badger paint stirrer (what an imaginative name) to ensure that all of the pigment is fully mixed with the carrier. I don't want tiny particles of unmixed pigment blocking the airbrush at the worst possible moment.
     
    On the left hand side you will see strips of 2mm greyboard that can be used as masks to prevent airbrush overspray going where I don't want it to.
     
    The rear of the tender has been supported by a folded paper towel to bring the whole length of the locomotive to the same level along the channel.
     
    You will have noticed that the spray booth filter will very soon need to be changed for a new one!
     
     

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