plasticpigeon
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I'm plastering a whole wall in lime plaster today. wish me luck!
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LadyArowana
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Good luck.
JoceAndChris
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Let us know if it's really true that more ends up on the floor than the wall - that seems to be the case from our brief flirtations with it!
Hope it goes really well, pics will be needed.
Hope it goes really well, pics will be needed.
plasticpigeon
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Some went on the floor but not most!!! It's not easy is it!!! It doesn't help that my wall is bowed. I might take it off and do it again, I was getting better near the end. I think more planning and maybe some grounds / screeds are needed for a flat wall. My scratching isn't very neat either.
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LadyArowana
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plasticpigeon said:
:shock:
Well done, in the picture it looks fine, actually better than fine, really good.
tobydog
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Looks good to me. Given that it's the scratch coat, so long at it stays up, isn't that what counts? It doesn't have to be pretty. I think the test comes with the other coats.
What did your plaster mix comprise of?
I know there are scratch combs which produce much finer lines closer together. I'm sure someone who knows exactly what they're doing will be along shortly to mark you out of 10.
What did your plaster mix comprise of?
I know there are scratch combs which produce much finer lines closer together. I'm sure someone who knows exactly what they're doing will be along shortly to mark you out of 10.
plasticpigeon
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I experimented here and predict what I have done will not be universally approved of. I patched in a bit of plasterwork before and used sharp sand, but being so gritty it was really hard work. This backing coat was a mix of 2 parts perlite to 1 part plastering sand with about 3/4 of a bucket of hydraulic lime 3.5. I realise now that I should have left the mix for a while before plastering as nearing the end of the wall it was much easier than at the beginning as the mix was much more workable. Next time I shall leave it for an hour and then knock it up again. This is my experimenting room. The rest of the walls are gypsum plastered anyway which was my mistake. I couldn't find a lime plasterer locally so used a bloke down the road. I got gypsum with a poor finish. Worst of both worlds so I'm trying stuff out so I get it right for the kitchen.
tobydog
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I'm practicing on our old kitchen but no big walls to do. It was suggested to me that adding chalk to the mix makes it better to work with so 1 of lime, 1 of chalk and 2 of sharp sand. I'm only rendering over a brick plinth and I'm not too fussed about a smooth finish because the rest of the room if pretty rough already. Hence the sharp sand.
masochists-r-us
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Looks pretty good to me. I'd be delighted if we can produce a similar standard of work. Did you go on a training course? Think we will go down the 'on site trainer' route with one of the rooms and if all goes well we could just keep going. Sounds like yet more hard labour of the 'dying in a ditch variety' though so should suit us just fine :lol:
Johnboy
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A couple of week-ends ago I did a 'Building with lime' Course through the Cotswold Conservation Board at the National Trust Ebworth Centre nr Gloucester. It was a very informative and well run week-end and we actually got to practice on a derelict stone cottage in the grounds. I wanted to have a go at rendering and brush up on my pointing and got plenty of opportunity to do both. I must say I would definitely recommend this type of course as it gives you the chance to 'have a go' before you tackle your own work. John Byrne was the name of the guy that ran the course, a good teacher (very patient!) and he also has quite an interesting blog which is well worth a look.
http://byrnesurfaces.wordpress.com
Saying that Plasticpigeon, it looks a really good job so far. The scratch lines look perfect to me, I would give you 10/10 no problem!
http://byrnesurfaces.wordpress.com
Saying that Plasticpigeon, it looks a really good job so far. The scratch lines look perfect to me, I would give you 10/10 no problem!
plasticpigeon
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Thanks for the kind words. I haven't been on a course, I'm a have a go hero, with a few old construction books and a willingness to experiment. Just like for hollywood movie stars, I think the soft focus is flattering the finish a little. I definitely scratched it too early, and I'm not sure my decision to put the skirtings on first was a good one. However looking at the plastering in the rest of the house it really looks like the woodwork was put on before plastering especially the architraves as some of these are quite considerably below the surface of the plaster.
I'll have to straighten a little with the next coat and hopefully get a nice finish with the top coat. In this place the entire plaster coat is only about 13- 15 mm thick, the render being about 10mm and very soft and sandy, the next coat is just for straightening and much lighter in colour so I'm guessing richer in lime and is only 1 to 2 mm or whatever is needed and then the topcoat is probably around 1 to 2 mm too but it is quite hard. Definitely still lime and sand but I would guess gauged with gypsum. I'm not planning to gauge with gypsum though.
So far the experiment with perlite seems to have worked, it has stayed on the wall and there aren't any cracks. Even though it isn't as strong as sand, I was interested in using perlite as it is less dense than sand making application easier (less likely to fall off the wall!) and has better insulating properties, although at 10mm thickness I don't suppose it will make any difference!!!!!
I'll have to straighten a little with the next coat and hopefully get a nice finish with the top coat. In this place the entire plaster coat is only about 13- 15 mm thick, the render being about 10mm and very soft and sandy, the next coat is just for straightening and much lighter in colour so I'm guessing richer in lime and is only 1 to 2 mm or whatever is needed and then the topcoat is probably around 1 to 2 mm too but it is quite hard. Definitely still lime and sand but I would guess gauged with gypsum. I'm not planning to gauge with gypsum though.
So far the experiment with perlite seems to have worked, it has stayed on the wall and there aren't any cracks. Even though it isn't as strong as sand, I was interested in using perlite as it is less dense than sand making application easier (less likely to fall off the wall!) and has better insulating properties, although at 10mm thickness I don't suppose it will make any difference!!!!!
Hi plasticpigeon,
It looks just right for a scratch coat to me - where would we be without that willingness to experiment! Interesting to see how the perlite has worked.
How did you do the external angle? Did you plaster around the angle or do you have a bead? I'm having a go at plastering a chimney breast at the moment and I've retained the old wooden bead (the fireplace was re-plastered in gypsum, except for the top couple of feet, in the 1980s when the previous owner took out the Victorian fire and blocked it up - luckily they kept the beads on the external angles). I would like to replicate the 'quirks' (the little indent) where the plaster meets the bead to avoid the inevitable gap that occurs when lime and wood meet, but I have no idea how it was done.
Good luck with the next coat, and I look forward to the photos...
It looks just right for a scratch coat to me - where would we be without that willingness to experiment! Interesting to see how the perlite has worked.
How did you do the external angle? Did you plaster around the angle or do you have a bead? I'm having a go at plastering a chimney breast at the moment and I've retained the old wooden bead (the fireplace was re-plastered in gypsum, except for the top couple of feet, in the 1980s when the previous owner took out the Victorian fire and blocked it up - luckily they kept the beads on the external angles). I would like to replicate the 'quirks' (the little indent) where the plaster meets the bead to avoid the inevitable gap that occurs when lime and wood meet, but I have no idea how it was done.
Good luck with the next coat, and I look forward to the photos...
worms
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plasticpigeon
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Hello
Fo anyone remotely interested, I did the top coat on one wall today. That was very tricky. As this is my experimenting room where basically everything has gone really badly apart from the window, I don't mind too much that it isn't great. I'm trying to go for a flat and smooth finish, just like with modern plaster as that is what the original lime plaster was like. I used a mix of plastering sand and building sand for this, but the plastering sand has random large bits in it, and is a bit coarse. I think to get a very smooth finish I shall just use soft building sand in the future, I know it is not sharp but I'm sure the original stuff wasn't made with sharp sand either. When I break up some old skim in my hand the aggregate is very fine and smooth. Another thing I have learned, is that it is much better to use a brush to flick water on the wall with rather than a spray bottle as it is possible to get the float onto the wall to smooth the surface more quickly before the water sinks in giving a better finish. Sorry for the bad photos, I only have a camera phone
Fo anyone remotely interested, I did the top coat on one wall today. That was very tricky. As this is my experimenting room where basically everything has gone really badly apart from the window, I don't mind too much that it isn't great. I'm trying to go for a flat and smooth finish, just like with modern plaster as that is what the original lime plaster was like. I used a mix of plastering sand and building sand for this, but the plastering sand has random large bits in it, and is a bit coarse. I think to get a very smooth finish I shall just use soft building sand in the future, I know it is not sharp but I'm sure the original stuff wasn't made with sharp sand either. When I break up some old skim in my hand the aggregate is very fine and smooth. Another thing I have learned, is that it is much better to use a brush to flick water on the wall with rather than a spray bottle as it is possible to get the float onto the wall to smooth the surface more quickly before the water sinks in giving a better finish. Sorry for the bad photos, I only have a camera phone
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Zebra
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Very good very good. Applause for the have-a-go-hero-approach!
Alex
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That plastering looks good. I looked at your last 2 photo's, looked at my own plastering and then realised that it must be compulsory for all lime plasterers to have the Ikea step stool somewhere near the wall that is being plastered. :lol: From now on I will expect to see your stool appear in all your future photo's and hopefully it will become as famous as a certain vacuum that is often mentioned on this forum.
Alex
Alex
plasticpigeon
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Ha ha, those steps have got around a bit. Always where the action is!!! I want to ask a piece of advice please. Despite my best efforts to damp the wall and get the plaster on quickly I still found the skim only stayed workable for maybe 15 mins. On this wall it was just about ok to throw it on and then trowel over it, like one would do with modern plaster. It's not amazing and a little way but generally flat, but I have another to do that is 9ft high and 16 feet long. I imagine if i try to do the whole wall in one go it will be too dry to quickly to trowel over once I've got the wall covered. Is it a case of getting the finish good as one goes along, or just doing it very quickly??
tobydog
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I'm glad you asked that question plastic pigeon. The same issue was driving me nuts over the weekend. I thought at first it was to do with the fact that the wall underneath is part brick and part thermolite block but it didn't matter how much I damped the scratch coat (only plasting 10mm to match up with gypsum above), the final skim was going off in less that 5 minutes. That was also over a very small area. I was wondering whether my mix was too dry or whether I should have just done one fine coat. Also I was using NHL which has a tendency to go off quicker than putty. I look forward to the responses.