The late great Allan Downes was an advocate of the polyfilla method albeit on the thicker Wills sheets 

@Mikkel, thanks for the compliment 🙂. I must get on and finish it, but I keep getting distracted…

As it happens, I’ve spent the past couple of days 3d printing test piece walls to determine the optimum size for brick spacing and mortar depth to give the best result for the polyfilla method. It works well for me in 7mm, but probably needs larger gaps than 4mm can provide to give a realistic result.

I’m finding that the 3d resin printed walls need wider and deeper gaps than laser cut ply, mdf or card, probably because with the latter the paint is at least partially absorbed by the material, leaving space in the mortar course, whereas in the former the paint sits on the surface of the resin and closes the gap, which therefore needs to be bigger to start with.

I also found that it is necessary to give the base colour time to fully harden and also give it a coat of Matt varnish to seal it before applying the filler, otherwise the colour can bleed into the mortar.

I’m very impressed by your station building, as I have been by all your other Farthing builds. It is modelling like yours that has inspired me to want more from my own modelling. Thank you.

10 hours ago, mullie said:

I've heard Polyfilla works well on Wills sheets where the mortar course is deeper though I haven't tried it as theses days I mainly use Slaters plasticard. I think I have tried most of the techniques you have tried and had many of the problems.

 

I think current favourite is a coat of matt grey primer to start off with, often from a rattle can, then lightly sand the brick work to remove paint from the brick faces which also adds texture. I then dry brush a variety of colours, usually using artists acrylics and talc for matting effect.

 

The new station building is looking excellent .

 

Always good to see a new post.

 

Martyn

Thanks Martyn, very useful. I really like the textured structures on your Upbech St Mary, so will have a play with those tips. And I have some Wills sheets kicking around, will try the Polyfilla method on them. I find them difficult to work with, but one or two of their pre-cut kits are attractive.

The depth of mortar courses does seem to make quite a difference to what works best. Which isn't made easier by the fact that sometimes that depth varies even within the same sheet, as I've found in some cases!

10 hours ago, gwrrob said:

The late great Allan Downes was an advocate of the polyfilla method albeit on the thicker Wills sheets 

Thanks Rob, I didn't know that he used this method. BTW I recently discovered that Allan's website is still in place. Mostly stone built structures on there, but I found a video of some of his brick-built structures. Extraordinary as always.

8 hours ago, GWR57xx said:

@Mikkel, thanks for the compliment 🙂. I must get on and finish it, but I keep getting distracted…

As it happens, I’ve spent the past couple of days 3d printing test piece walls to determine the optimum size for brick spacing and mortar depth to give the best result for the polyfilla method. It works well for me in 7mm, but probably needs larger gaps than 4mm can provide to give a realistic result.

I’m finding that the 3d resin printed walls need wider and deeper gaps than laser cut ply, mdf or card, probably because with the latter the paint is at least partially absorbed by the material, leaving space in the mortar course, whereas in the former the paint sits on the surface of the resin and closes the gap, which therefore needs to be bigger to start with.

I also found that it is necessary to give the base colour time to fully harden and also give it a coat of Matt varnish to seal it before applying the filler, otherwise the colour can bleed into the mortar.

I’m very impressed by your station building, as I have been by all your other Farthing builds. It is modelling like yours that has inspired me to want more from my own modelling. Thank you.

Thank you, also for the insights! I would be happy if I could achieve the mortar courses on your coaling stage, and  look forward to seeing your 3D printed walls. 

It's interesting that the paint is absorbed by the ply/mdf/card, I had not considered that. So we have to consider the nature of the material as well, along with the width and depth of the mortar courses, the "filling" used for the pointing (paint, filler, other), the priming and base coat, the timing of it all, etc. No wonder results vary. 

Glad if it's of use Matt. I'm sure stone-built structures have their own particular challenges, I haven't worked much with that. Looking forward to what you come up with. 

6 hours ago, Mikkel said:

Thank you, also for the insights! I would be happy if I could achieve the mortar courses on your coaling stage, and  look forward to seeing your 3D printed walls. 

Kind of you to say Mikkel, but I'm still fumbling my way along picking up gems of advice from the really good modellers here...

These are the latest test pieces I've been experimenting with:

The two pieces on the right are laser cut card, one of which was sealed with Mod Podge before painting & filling (just to see what, if any, benefit it gave).

On the left are my first three trial 3d printed pieces. These are U shaped, intended to wrap around the base of a buttress. The top course is chamfered.

Top was a test to see if the wall could be printed face down on the build plate (for speed). Answer a resounding NO as the "elephants foot" has completely obliterated the brick detail.

Middle: as my laser's kerf is approximately 0.2mm, this piece also has 0.2mm gaps between bricks. Hardly any filler has stayed in the gaps. The photo makes it look better than it is because of the very low sun producing nice shadows.

Bottom: a test with different gap widths. Starting at the top row of chamfered bricks, left to right two bricks at a time the gaps are 0.3; 0.4; 0.5; 0.6 & 0.7mm. Then below that, top to bottom two courses at a time the same sequence of gaps. From this I picked 0.4mm as the gap to use on the next test piece.

I printed two copies, the lower one having a small amount of texture applied to the surface of the bricks. It is not very noticeable though, so probably not worth the effort.

These are prior to applying the filler, to show that I haven't flooded the gaps with paint but neither have I worried too much about getting some paint in them.

The filler has been freshly applied here. I'll leave it to fully dry and set then give it a brush over to clean the excess off the brick faces, but I think it compares quite well with the mortar on the laser cut pieces.

Quote

And I see that @GWR57xx used Halfords spray paint, which I think is enamel. I used Vallejo Acrylics, maybe that’s the problem.

Mikkel, Halfords paint is actually acrylic, though the key difference is that it is a solvent based one (I have yet to find a suitable solvent to dilute decanted paint and soon gave up on the idea). I'm thus guessing it's down to Vallejo being water based (right lines of thinking, just a subtle difference).

Mikkel and GWR57xx,

@Simond suggested using polyfiller on my stone walls, but I was concerned that he had used it in 0 gauge and I was not sure the mortar gaps would be big enough in 00.  Thank you, I think I have my answer.  If I did the sort of experimenting that you have done I am not sure I would finish anything.  (Now, now, I have finished at least one model, I think).

As to the milky thickness of paint to fill the mortar, I have used that successfully on the Ratio station kit of ?Corfe Castle, but the gaps between the stones was huge so I was surprised how well it did on your trial.

18 hours ago, GWR57xx said:

 

Kind of you to say Mikkel, but I'm still fumbling my way along picking up gems of advice from the really good modellers here...

 

These are the latest test pieces I've been experimenting with:

 

The two pieces on the right are laser cut card, one of which was sealed with Mod Podge before painting & filling (just to see what, if any, benefit it gave).

On the left are my first three trial 3d printed pieces. These are U shaped, intended to wrap around the base of a buttress. The top course is chamfered.

Top was a test to see if the wall could be printed face down on the build plate (for speed). Answer a resounding NO as the "elephants foot" has completely obliterated the brick detail.

Middle: as my laser's kerf is approximately 0.2mm, this piece also has 0.2mm gaps between bricks. Hardly any filler has stayed in the gaps. The photo makes it look better than it is because of the very low sun producing nice shadows.

Bottom: a test with different gap widths. Starting at the top row of chamfered bricks, left to right two bricks at a time the gaps are 0.3; 0.4; 0.5; 0.6 & 0.7mm. Then below that, top to bottom two courses at a time the same sequence of gaps. From this I picked 0.4mm as the gap to use on the next test piece.

 

 

I printed two copies, the lower one having a small amount of texture applied to the surface of the bricks. It is not very noticeable though, so probably not worth the effort.

These are prior to applying the filler, to show that I haven't flooded the gaps with paint but neither have I worried too much about getting some paint in them.

 

 

The filler has been freshly applied here. I'll leave it to fully dry and set then give it a brush over to clean the excess off the brick faces, but I think it compares quite well with the mortar on the laser cut pieces.

 

Very impressive results! Thanks for sharing them. Your experiments may also interest @David Bigcheeseplant who is 3D printing Princes Risborough station (although in 4mm scale, which of course is a different kettle of fish in this respect). The 3D printed pieces do look good. I can see why you experimented with texture on the 3D prints, I like the textured look of the lasercut pieces.

You mention that the 3D printed piece in the first shot looks better than it is, and that little filler stayed in the gaps. What I find interesting though is that it looks quite similar to the (Edwardian) brickwork at e.g. Newbury.

Which makes me wonder whether we sometimes exaggerate the visual impact of mortar courses on models - especially 4mm ones. I may have mentioned it before, but when I look closely at this great model on Jim Smith-Wrights New Street (built from SEF sheets by the the way), I'm not sure he has applied any pointing at all. Yet I think the model works very well.

It does, of course, depend on the style of pointing on the prototype. Here's a photo of the (sadly closed) pub just above Newbury station. A very different look compared to the station.

14 hours ago, 57xx said:

Mikkel, Halfords paint is actually acrylic, though the key difference is that it is a solvent based one (I have yet to find a suitable solvent to dilute decanted paint and soon gave up on the idea). I'm thus guessing it's down to Vallejo being water based (right lines of thinking, just a subtle difference).

Ah, thanks for clarifying that. I've always been curious to try out the Halford's range as they seem to give very good results. We can't get them here though. So I suppose it will have to go on my shopping list next time I cross (under!) the channel.

13 hours ago, ChrisN said:

Mikkel and GWR57xx,

@Simond suggested using polyfiller on my stone walls, but I was concerned that he had used it in 0 gauge and I was not sure the mortar gaps would be big enough in 00.  Thank you, I think I have my answer.  If I did the sort of experimenting that you have done I am not sure I would finish anything.  (Now, now, I have finished at least one model, I think).

 

As to the milky thickness of paint to fill the mortar, I have used that successfully on the Ratio station kit of ?Corfe Castle, but the gaps between the stones was huge so I was surprised how well it did on your trial.

Chris, I can't remember what sheets you used on Traeth Mawr, but it seems the Polyfilla results partly depend on that. Maybe you have some off-cuts to try it on? 

4 hours ago, Mikkel said:

 

Ah, thanks for clarifying that. I've always been curious to try out the Halford's range as they seem to give very good results. We can't get them here though. So I suppose it will have to go on my shopping list next time I cross (under!) the channel.

 

 

Chris, I can't remember what sheets you used on Traeth Mawr, but it seems the Polyfilla results partly depend on that. Maybe you have some off-cuts to try it on? 

 

 

Mikkel,

I have used Slaters, random stone, so the mortar lines are not very deep between the stones.  On the platform facings it is SEF and the mortar lines are deeper.  They might be better for the polyfiller method.

Mortar.  I think older mortars were more grey than white, especially with time, but as you say it depends on the building.  Most houses around here are 40-50 years old and have red bricks with distinctive yellow mortar, but the ones over the back to us have much paler bricks with a dark mortar.  Photos of your buildings are always helpful, but the bricks and mortars will have aged and, depending on where the building is the air quality will have changed.  Since the smokeless zones came in during the sixties many buildings in cities have been cleaned up, and even where they have not been they would have been cleaned by the rain,  (I always thought that the Natural History Museum was a dirty brown colour naturally, until it was cleaned and exposed the beautiful multicoloured stone work.

Interesting. So when it comes to stone sheets SEF have deeper mortar courses than Slaters? On my brick sheets it's the other way round. In other words, no universal rules can be applied.

Regarding mortar. I have been wondering whether and how much it darkens over time naturally. I have not noticed it in houses I have lived in or known - but that is also a short timeframe. Newbury station is now 114 years old. And then there is the environmental effect that you mention.

And then of course the effect of repair work and modifications. Here is one end of Newbury station. Quite a lot of stuff going on here, brick and mortar-wise:

Not a lot of relief there, and thin mortar lines. An argument for brick paper. In fact, it looks like brick paper!

Nothing to show you now, and talking small sizes of buildings in 0 scale, but in the past I’ve painted embossed plastic sheets for bricks or stonework by an overall wash, using Humbrol flat paints, maybe patchy dabs of slightly different tone. Then do a paint mix for mortar and load a sprinbow pen, going along all the courses and risers by hand. This is tedious, but the courses aren’t as prominent as when you’re flooding and wiping.

p.s. There’s always doing this, which looks great for old buildings:

https://www.westernthunder.co.uk/threads/old-parrock.6209/page-5#post-172805

That's an interesting method with the springbow pen, hadn't heard of that before. Thank you.

The Pendon method in the link gives a lovely result. I believe it is also the approach Stephen Williams used on his stone-built Faringdon structures, as seen in his GW Branchline Modelling books. 

Excellent master class as per usual.  Like the paint and pigment method out of all your experimentation too.  Assuming that the SEF sheet is the lower one in that picture I prefer it to the top one even though you say the Slater’s brick is better defined - it just looks like the mortar is more realistically sized to me.  

Thanks Mike, interesting thoughts on the SEF vs Slater's sheets. In my view the both suffer from overscale mortar courses. Not sure why really, perhaps it's easier to print - or maybe it's like figures where heads have traditionally been modelled larger than they are because we expect the features to be clearly visible.