There are a number of churches on Crete whose wallpaintings have been whitewashed at various times. My fictional church in a fictional village lost its roof in a fire in world war two and the priest at the time, to defend the wallpaintings from the ravages of weather, ordered them whitewashed. Now, 50 yrs later, my fictional character wishes to remove the whitewash and reveal the saints whose eyes he feels watching him. He will do research online at an internet cafe and will find suggestions ranging from lunatic to wise, and he will try them all out on a corner of the wall, until he gets it right. I need to know what right might be, so when one of you reads the novel you don't disbelieve the rest of the story because these details aren't possible.

A painter friend who lived in Greece for awhile said he thought the calcimining done each spring in villages probably had very little binder and seemed flakey as he remembered. That would make picking it off not such an onerous task, I think. He also mentioned cleaning smoke and dirt off tempera icons with white bread dipped in orange juice. But that doesn't help with the wall paintings.

I have found the Getty website and have noted abstracts that might help, but I havent figured out how one gets the actual texts of these articles. The University of Washington library has one of them, but even the University of California library system doesn't have the others. Suggestions?

One abstract mentioned using Primal AC 33 to consolidate the murals, with an inert powder as necessary. Primal AC33 is called Rhoplex in the US. What is it? Could a layman buy it? Would he need it? Or once he scraped the whitewash off these walls, would they crumble at his feet?

Another abstract mentioned removing whitewash then adhering loosened plaster with a 15-25 percent water emulsion of polyvinyl acetate. Is that Primal AC33?

Thanks in advance for any light you can shed.

Kremer-pigmente.com is a source of European preservation materials. True, the Getty resource doesn't tell you exactly how to order an abstract, but this what academics do all the time - if you could only get a research grant to travel where the libaries are!

it seems hard to find info on what modern paintmakers
do,know any sites to discuss such concerns?

i have used 3 types of limewash,one very washy and unbound,another one a good product and yet a further one
that is fantastic.
i think these people keep their cards down.

we get bags of lime putty in solution here in oz,thick plastic bag/double skin with an easy access spout. they are designed for plasterers and are cheap $5 for about 10kg
or is it 20 kg - i forget.

perhaps i could make a strong brew myself....hence info about binders.

gary you might check out this site
www.abilityproducts.com.au
it is very interesting on various materials (synthetic)
oxides,additives for cement....check their e-spheres.
best wishes.

I need to setup a "download area" for the stuff like this around here, just having a problem deciding how - perhaps I should make a download link, however here are so many links as it is... Any suggestions?

Joe, any ideas? or limewash how-to?

ilia

is his email adress around?
>
>I need to setup a "download area" for the stuff
>like this around here, just having a problem
>deciding how - perhaps I should make a download
>link, however here are so many links as it is...
>Any suggestions?

this is such strong hands on forum that some link locatated within the forum where all the smart ideas/receipes could be data dumped would help....rather than having to move through many posts to retreive _that really neat mix of limeputty/marble sand and???? for example.
limitation: is it too cumbersome to install?
might be worth a try.wonder if you can set it up...
>
>Joe, any ideas? or limewash how-to?

i think what differs with modern paintmakers might
be how clever they are with special binders.
for example: porters' distemper (an old-fashioned paint
predating the acrylics) is a beautiful material
and much more sound than the distemper i remember
when i was a kid.
it just gets me that it aint rocket science and i would
like to mess with what i put on the wall.

i think i learnt from one of gary's posts about the value of lime water....that surface water on top
of the lime putty.
cheers joe.

The best binder for lime and lime proof pigments is silicate based. I am very impressed with potassium silicate paints on plaster, concrete and lime mortar. They are cheap to make yourself, very durable, allow the surface to breath, and dry absolutely flat - like true fresco. The acrylic resins are just not working out anywhere where moisture and heat expansion and road vibration/surface movement is a factor. The acrylics also 'gum up' any mixture, so instead of the sensation of troweling 'ball bearings' - you have the sensation of trowelling sticky glue.

The silicate binders work so well because one of the secrets we have not revealed about true fresco is that the lime partially dissolves the silica sand to form calcium silicate. So adding another type of silicate (other than sodium silicate for some odd reason)is a natural mix for strength.This is also why white cement, another silicate, works so well with lime and sand. For a smooth 'plastic' surface a proportion of the dolomite and marble sands are better - they are softer and form more of a putty, not so soft to fall apart, but soft enough to self heal. I tried an experiment three years ago, ultramarine silicate paint on fresh white cement, lime putty and silica/dolomite sand - and after three years of snow, constant sun, frost and rain - it is still as bright and strong as the day I painted it.

Good 'sharp' sand is more important to fresco than lime, pozzolans (or what the trade calls 'fly ash)' is another very fine, sharp sand. Magnesium in lime, like calcium carbonate in paint, forms a useless filler powder, with no strength, but this only becomes a factor in freeze/thaw cycles, or constant running water, and is compensated for with the use of good sands.

Lets also not forget the country with more square metres of outdoor fresco than any other is Mexico - and the lime used were NOT European or even near as pure as contemporary North American limes, yet they are weathering extremely well. Although many of the pigments of Mexican fresco in the 20th century were imported from France through a store in Mexico City. The mayans and the aztecs were also painting fine quality lime stucco and fresco well before the Europeans. They too were very careful about the sands and the water used, and Diego Rivera and his master plasterer sought out the Mayan sources of materials in creating their magnicent frescoes.

Since we in North America love the numbers game - Rivera's series of 124 frescoes in the patio of the Public Education Ministry cover 1,585 sq. meters, or over 17,000 sq. ft.: the equivalent of a a painting one foot tall and over three miles long. This is just one of the many frescoes in Mexico, and one of many in Rivera's short career.

can you post a receipe here gary?

very durable, allow the surface to
>breath, and dry absolutely flat - like true
>fresco. The acrylic resins are just not working
>out anywhere where moisture and heat expansion
>and road vibration/surface movement is a factor.
>The acrylics also 'gum up' any mixture, so
>instead of the sensation of troweling 'ball
>bearings' - you have the sensation of trowelling
>sticky glue.

here we are badmouthing the wonderful world of acrylics!!!!! in 1962 people thought they were sent from god.
>
>The silicate binders work so well because one of
>the secrets we have not revealed about true
>fresco is that the lime partially dissolves the
>silica sand to form calcium silicate. So adding
>another type of silicate (other than sodium
>silicate for some odd reason)is a natural mix
>for strength.This is also why white cement,

the white cement i have recently bought is twice as expensive as standard portland and comes from malaysia
or indonesia is this the same animal? do you know where yours comes from?

>another silicate, works so well with lime and
>sand. For a smooth 'plastic' surface a
>proportion of the dolomite and marble sands are
>better - they are softer and form more of a
>putty, not so soft to fall apart, but soft
>enough to self heal. I tried an experiment three
>years ago, ultramarine silicate paint on fresh
>white cement, lime putty and silica/dolomite
>sand - and after three years of snow, constant
>sun, frost and rain - it is still as bright and
>strong as the day I painted it.

sounds teriffic!
>
>Good 'sharp' sand is more important to fresco
>than lime, pozzolans (or what the trade calls
>'fly ash)' is another very fine, sharp sand.
>Magnesium in lime, like calcium carbonate in
>paint, forms a useless filler powder, with no
>strength, but this only becomes a factor in
>freeze/thaw cycles, or constant running water,
>and is compensated for with the use of good
>sands.

so necessary to be doing stuff to apply and fix in the fast lane this kind of information....thanks for putting it online like this....i reckon i could talk to
some plasterers down the road and they would be quite unfamiliar with this stuff.
>

The white cement in Canada is made in Canada, but the Asian one is one the market too, both are more expensive. White cement is about 30% stronger than grey portland cement, and it takes pigment well. I have some materials coming which advocate sodium silicate liquid in concrete, will have to see what they say.

can you spell out the significance of sodium silicate?

yes the acrylics are used in cements paints.
i remember yr fresco panel constructions... must backtrack and have another look.

can't get this message together properly...got to split
and go to work - SOS job 4.10 am
cheers ....pick up the pieces later - joe.