Mortar Course painting

[Ray H]

I painted some Slater's embossed plasticard yesterday in Humbrol matt enamel 100 and left it to dry overnight in the house.

 

I tried to colour the mortar course this morning with a slightly thinned Humbrol matt enamel 121 and all I seem to have succeeded in doing is to turn the matt 100 to a lighter shade with little impact on the mortar course.

 

I also tried the 121 straight from the tin but that had the same effect.

 

In both cases I attempted to remove the excess 121 - i.e. that which hadn't permeated into the recesses that represent the mortar course - within a few minutes because of the impact that it was having on the colour of the general area. I was using kitchen roll to remove the excess.

 

I've obviously got something wrong. Can someone point out the error of my ways please?

 

Thanks.

[BlackRat]

The 'enamel' hasn't really gone off, it lifts easily and mixes like this unless it has completely dried.

 

Try using acrylic for the base coat, you can over paint in minutes and you can even wash any over laying enamel on or off with thinners such as white spirit.

 

HTH.

[Ray H]

The 'enamel' hasn't really gone off, it lifts easily and mixes like this unless it has completely dried.

 

Try using acrylic for the base coat, you can over paint in minutes and you can even wash any over laying enamel on or off with thinners such as white spirit.

 

HTH.

 

I'm painting a bridge that is structurally complete and had enamel applied all over.

 

Do I just leave it for a couple more days in the hope that it will totally cure or can I try using acrylic instead of enamel for the mortar course?

[bécasse]

I always try to avoid painting the bricks on Slaters' Plastikard brickwork, whether I am working in 4mm or 7mm, and I just paint the wall or w.h.y. all over with a suitable colour paint to represent the mortar. Once it is dry to touch, I scrape the paint off with a scapel (the rounded ones work best) which leaves a good representation of the mortar lines and tones down the brickwork. Finally I use powders to represent, for example, areas with mould or damp.

 

The only time that I paint the bricks themselves is if I need to represent specific colour effects on the brick face, for example blue carbonate burn marks from firing, and in this event I spot paint the bricks and leave them to dry really thoroughly - typically a fortnight or more - before using my usual techniques. Some of the extra colour gets scraped off but sufficient remains to produce the desired effect.

 

In your case, I might try scraping a fairly hidden area to see if the lightened brick colour you have got to does produce an acceptable result when scraped. Another possibility is to try dribbling a very dilute solution of the mortar colour in white spirit over the brickwork held at an angle to the horizontal - with the aim of getting it to settle in the mortar lines. Don't touch the result at all for several days.

 

Here is an example of one that I cooked (about 43 years) earlier. Much of the prototype brickwork was badly marked with blue burns, but the small lean-to on the left was a later addition in a much cleaner brick.

 

[Ray H]

Thanks for sharing that.

 

What I did try subsequent to posting is what I might call wet brushing.

 

I took a minute drop of acrylic on the corner of the end of a chisel brush and swept it lightly across a small area of the previously painted brickwork. I immediately dipped the brush into water and then spread that over the acrylic to disperse it, adding more water as necessary, thinning the acrylic all the time.

 

The result (now it is dry, as I've been out all afternoon) is a discernible colouring of the mortar course with the side benefit of an element of lighter colour weathering all over with which I'm reasonably pleased.

 

I think I can rescue some of the earlier areas  that didn't like the enamel with a similar technique using darker acrylic colours.

 

A plus side of this method appears to be that instead of wiping the brush wastefully on a piece of cloth or kitchen roll as with dry brushing, any paint taken from the supply ends up on the model.

[Gravy Train]

Hi,

Have you tried to apply the mortar course first then add the brick colour after? :-)

You may also find that the overall colour of the brickwork can be heavily effected by the mortar colour rather than the brick colour itself.

I have attached a photo of some brickwork done the opposit way, mortar first then brick colour.

cheers

Peter

[Ray H]

 

Peter

 

Thanks for the suggestion which alas came too late as the structure had already had the base coat of red. I will experiment with applying the mortar course first on the layout's other bridge.

 

I think I shall leave well alone now as I'm bound to make things worse - that almost happened last evening when I tried using some powder colouring and put far too much on. Fortunately it is where it doesn't matter and most of it has been able to be toned down anyway.

 

I did find that it was best to apply just enough water to keep the surface wet but not that much that the liquid started to accumulate at the edge of the plastic. It is amazing how far a pin head full of paint goes!

[ROY@34F]

I use a method I saw an old gent. using many years ago at an EM show . Paint the Slaters brick with your chosen mortar . I use Humbrol enamel , thinned so it runs well into the courses . Wipe most off while wet . When dry , rub down flat with wet &dry on a good flat surface (glass ?) keeping wet to clear the grit . I use about 600 grit on a block of wood . this flattens the rounded surface of the Slaters moulding as well as the paint of course . The more you go the better it looks , though you will remove the courses if not careful . You can then crayon the surface with what colour you prefer , and seal with matt varnish or similar . Works well for me . "Water colour" crayons work better than pastels I find .

Hope this helps .

Gravy train's work looks very good ; he must flatten the surface I think , but does he paint the bricks ?  He's the Master of course .

Roy .

[Sweven]

I paint the bricks first using enamel (Humbrol 70, 100, 62 in various combinations, picking out some bricks for variation - although I am colour blind so my choices might be strange!) and then mortar with a thick off-white poster paint (acrylic) which I leave for a couple of minutes and then wipe off the bricks with a wet paper towel, leaving it in the courses. It is a bit like grouting tiles.

 

As Peter said above, putting the mortar on after painting the bricks does affect the brick colour, but to me it dulls them down to about the right shade.

 

Here is a photo where I am in the process of applying the mortar to the left-hand wall. If I don't like what I have it is easy to remove the mortar with more water and try again...

 

 

Cheers

John

[ROY@34F]

That looks very nice John (Sweven) . Might try that myself .

Roy .

[Ray H]

That's what I tried as well. My problem was the acrylic was dry before I could rub it off even if only tackling a very small area. That said, I didn't thin it down.

[Sweven]

Thanks Roy.

Yes the acrylic I am using is a cheap kid's ready-mixed water based poster paint and seems to stay 'workable' for perhaps 10 minutes.

[Gravy Train]

Hi folks,
I think we might be at cross purposes re 'mortar effect' on brickwork.

I have found that no matter what combination you use with regard to painting your brickwork, the overall colour of the brick will be determined dramatically by what choice of mortar colour is applied.

For example, if I use No70 brick red and No64 for mortar colour it will give a fairly light to medium tone to the brick colour but if I use No79 for my mortar colour to give an aged look and use No70 brick red, watch what happens to the overall brick colour, this is the point I am trying to make.

 

I showed this effect as a demonstration at the 'Hobby Holidays' teaching course I tutored a couple of years ago, the flattening of brickwork as in rubbing down, I find un necessary as when the mortar colour is applied first, its takes the round edges out of the brick courses giving the illusion of sharp square edges as the paint fills the definition in the Brick.

I hope this clears up my point, grammer was never my strong point :-)

 

I am at present putting together some 'how to'  Articals together on  'Architectural modelling' and hopefully may be benefit for some, there is one on applying mortar and brick colour all in one go to get a result :-) 

cheers

Peter

ps: lovely building you have there John. :-)

[Sweven]

Thanks Peter. Yes I take your point regarding the mortar colour - I have only ever applied my mortar after painting the bricks rather than the other way around; but the colour of the primer under the bricks certainly affects their final colour. Looking forward to reading about how you apply mortar and brick colour in one go! Cheers John