Full Chisel Blog

March 12, 2010

Making Paint [again]

Filed under: Finishing,Historical Material,Of Interest,Uncategorized — Stephen Shepherd @ 3:10 pm

Due to the fact that a month of my blog was erased, this post, which I hope is not offensive will be reposted. 

Making Paint

“using the best materials, and

executed in a workman-like manner,” 

 

Furniture has been painted for centuries [never with milk], the earliest modern reference I have found is 1225.  People today think that it is a near crime to paint fine wood, but you need to remember that our ancestors were surrounded by wood.  Living in the largest mixed mesophytic climax forest in the hemisphere was overwhelming at times.  Trees were cut and burned to open land for farming and many of the trees were too large to harvest for lumber, they wouldn’t fit in the saw mills.  Most of their homes were made of wood, everything around them was wood so painting furniture and woodwork brought a little color and variety into their lives. They needed a break from wood and chose to paint their woodwork and furniture.  Painting was done on Windsor and Hitchcock chairs to cover up the fact that they were constructed of different woods.  An elm seat with hickory spindles and beech legs gets a uniform appearance by painting a solid color.  In the nineteenth century ‘fancy painted chairs’ were popular and many fine polychrome examples have survived with dramatic coloring, stencils and stringing all painted on the wooden framework of the chairs.

It costs extra to paint furniture, so it was a conscious choice to cover the natural grain of the wood with an opaque colored finish.  It was considered more cosmopolitan and sophisticated to have painted furniture and that is reflected in the premium price that was charged for adding paint.  Careless stripping old furniture of its aged paint to reveal the ‘beauty of knotty pine’ destroys forever the intentions of the originating craftsman and can reduce the price of these antiques by 80%.  That’s right 80% of the value of an antique is in that old, cracked and crazed painted finish.  It’s alright to paint furniture.

Paint is a mixture of a vehicle (solvent), a binder (linseed oil) and pigment.  There are other additives that were included, sometimes following traditional formulae and sometimes from the experience of the painter. Painters, polishers and finishers were separate trades during the nineteenth century in larger cities.  In smaller more remote locations the woodworker would have to paint their own work.

Paint in the nineteenth century was sold by the pound indicating that it was in powdered pigment form, not a ready to use liquid.  One pound of red lead is about a third the volume of one pound of burnt umber pigment. It was then mixed up according to the user by adding linseed oil and turpentine and other ingredients to make an opaque covering.  Most ‘paint’ is a mixture of varnish and pigment, with more varnish it becomes glossy and is referred to as ‘enamel’.

The paint that was sold was very finely ground earth pigments, some innocuous and others insidious. Care should be used when working with these pigments while they are in the powdered form.  And some like vermillion (mercury disulfate) and lead (Pb) can be dangerous even when bound up in the vehicle. For very detailed work like fine art oil paintings, the painter would sometimes grind their pigments again in linseed oil with a muller and plate, producing much finer pigments required for this work.

I do, on a regular basis, make ‘paint’ using liquid shellac with a sufficient amount of powdered pigments to produce an opaque finish.  One advantage of this technique is that it dries instantly, works for restoration, touch-ups and for curatorial considerations is reversible.  I have used it as a base coat for painting and graining, but isolate it with a coat of oil or varnish to prevent the over graining, if alcohol based, from solving the base coat.  The amount of shellac will determine the luster of the finish, less produces a matt or satin finish and more will produce a shiner finish.  A fast drying paint can be an advantage when a finishing room is not available or there is a chance of airborne dust or if you are impatient.  I thought I came up with this, but after researching the subject for this work I discovered that it has an historic precedence.  Not as durable as oil paint but works fine if protected by a good oil varnish.

Mixing paint can be a simple process depending upon the recipe.  Some old formulations require heating, straining, mixing and aging, others are simple mixes of oil varnish and pigment.  One characteristic of old paint and shop made paint is the fact that the pigments can settle out of the solution and accumulating on the bottom of the container.  The pigment is suspended in the oil varnish and gravity can separate the heavier bodied pigments causing them to precipitate from the liquid.

I mix up batches of paint as I need them and try and make just enough for the job.  It is possible to store extra paint and I will discuss that later.  Traditionally containers made of glazed pottery were common and inexpensive.  Jars, pots and pipkins made of heavily glazed pottery, red ware should have a heavy glaze, and salt glaze is also good for paint containers.  Ceramic containers (refined pottery) also works with a proper glaze.  Glass containers were rarer during the period but were available.  Glass gives you a visual to make sure the paint hasn’t separated as well as how much paint is left.

Hot dipped tin (in the nineteenth century it would be sheet wrought iron dipped in molten tin), today tin containers are made of steel sheet and electroplated, hot dipped tin is available.  Tin makes an excellent container for holding paint while you are painting, especially a pail with a bail and a lid.

 

If you are going to make your own oil paint, I would suggest that you use a good quality boiled linseed oil and add some stand oil or sun thickened oil to help it flow better and dry faster.  The more pigment you add to make it opaque can also effect the shine of the paint when it dries.  You can also add calcium carbonate [whiting] to thicken light color paints but it will also remove the shine.  You can add oil based gloss varnish which will thicken, aid in drying and add a shine to the paint.

Shop or studio made liquid paints need to be stirred frequently as the heavy bodied materials can settle out, I notice this happening, particularly using iron oxide pigments, so I leave my perforated stir stick in the paint as I am using it and stir the paint every few minutes to insure a uniform consistency, color and intensity of the mixture.  Don’t ever use the paint brush to stir the paint.

It is possible to use fresh made paint, however it does benefit from aging in a tightly stoppered container.  The container on the left has too much air space, the one on the right has pebbles that raise the level to remove excess air.  Paints made with minerals that act as dryers such as burnt umber, manganese, iron and lead base will begin their reactions to polymerize the mixture chemically.  This is useful as it will help the paint dry faster and storing the paint for a period of time will enhance its drying characteristics.

 

 

 

 

 

 

 

 

 

Stephen

4 Comments »

  1. Yes… hot dipped tin is available from http://www.hotdiptin.com. Should I start making paint canisters?

    Shay Lelegren
    tinsmith

    Comment by Shay — March 16, 2010 @ 8:55 pm

  2. Shay,

    I actually have a description of a varnish pot that I would like to have made, you will have to read it and see if you can figure out how it was made and exactly what it looks like.

    The bee smoker hasn’t progressed, nor has the stitching horse, I am in need of some thick Chestnut, got any?

    Stephen

    Comment by Stephen Shepherd — March 23, 2010 @ 9:48 am

  3. I purchased an old wardrobe – circa 1860. It has a pigment (of some sort) on the unfinished areas – back & interior side panels. The pigment is reddish and cannot be removed without exhaustive wiping & wiping. What is this product? Could it be toxic? Am I distroying the character of the piece by trying to remove the residual powder? I am concerned the pigment will stain my clothing if it comes in contact to the interior surfaces if I leave it as it is. Any advice you can provide is greatly appreciated.

    Virginia in Virginia

    Comment by Virginia W. — August 13, 2010 @ 4:46 pm

  4. Virginia,

    Welcome and the residue is probably red lead paint used as a base coat for a grained finish. If you have a hard time wiping it off then I don’t think it will rub off on your clothes. You will decrease the value if you remove the original finish, which is what you have. Brush off any loose stuff that might get on your clothes and put some protective acid free paper inside if it is still a problem.

    Stephen

    Comment by Stephen Shepherd — August 13, 2010 @ 6:40 pm

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