Blocking powder

Gold leaf needs an adhesive. When putting gold on leather bindings the traditional adhesive, called a glaire, was egg whites. More modern glaires like Fixor or BS Glaire, use shellac. Here is a blog post I made on making your own glaire: you can find it here.   It was part of a struggle to figure out why I was being sent unusable Fixor (a modern glaire) without any real logical explanation and then figuring out how to easily make better glaire, that actually worked for less cost.

A hundred years ago gold leaf was used on cloth bindings as well. But you can’t use a liquid glaire on cloth because it would stain. You could, I suppose, make an impression and then carefully put the gold in that space, but if the impression was made using a blocking press, you’d have to fill the impression without moving the book in the press and . . . it would be pretty much impossible I think.

Blocking powder is a powdered glare. It is also made from shellac.

I first learned about blocking powder in Sweden where Per Cullhed used it when tooling. He would use Fixor for his gold tooling. But there are often losses in tooling, places where the gold doesn’t stick. You try again with the gold and if it doesn’t stick the second time often you have to re-glaire the spot. And then wait for the glaire to dry before proceeding. It takes time. Some might think it wastes time.

Per would use blocking powder in the spots that needed reglairing, which meant that he could re-tool the spot immediately and successfully.

When I returned from Sweden I tried to buy it from the usual suppliers, but no one had it. A while ago, many years after returning from Sweden, I asked around and found a few recipes.

I made this one and it’s worked really well. It’s from Pleger’s book, Bookbinding and Its Auxiliary Branches, Part 3: Blank, Edition and Job Forwarding, Finishing and Stamping, on page 234:

1 part gum arabic
1 part gum sandarac
1 part gum mastic

I mixed them in a coffee grinder to a very fine powder and ended up with about a third of a cup. Which is a lot considering how little is used each time.

David Lanning, of Hewit Leather, had another recipe:

25% French Chalk (Tailor’s Chalk)
75% Finely Ground Shellac

There is no question that would work as well.

It’s interesting to note that Pleger does not like using “gilding powder.” He writes, “. . .beyond the lettering of individual names in addition to the afore-mentioned materials it should not be used. . . .”

Pleger actually has two other recipes, one using gutta-percha which I wanted to use because it sounded like a fun thing to use, but I couldn’t find it anywhere. In spite of its use in dentistry, and that my sister works in the dental industry, I couldn’t find it anywhere.

His third recipe is:

1 part shellac
2 parts copal

I purchased the materials from Kremer Pigments. The cost of the three items in the first recipe was about $60 for what feels like a lifetime supply.

To use the powder you take a fine bristled brush and dust it evenly over the area you are filling in. You might have to vary the heat of the tool a little bit, of course. Then pick up the gold and tool it.

It really is just like any other finishing. I do think it would be a bit of a pain to use it over a whole cover, but I might be wrong about that. And we know that Pleger would have words with you if you did that.

Try it. You’ll end up thanking Per! And he deserves it.

Fixor: part deux, finis!

I have a large project ahead of me so I started picking things up and putting them away.  Don't know why, except it always makes me feel better about the world.  And myself.

In the midst of that I found a bag of shellac which I've had for several months, since I made some blocking powder (which I will post about shortly).  Shellac comes as flakes but those flakes turn into a block if they sit around too long. This bag had four or five blocks the size of marbles and about the same volume of flakes.  I needed to do something with it.

So I decided to make more of the fake Fixor glaire, used in gold tooling as described in the previous blog entry.

The beauty of fixor, or other shellac glaires, is that they pretty much last forever.  So I decided to use the whole 100 g. bag and be done with it.  The shellac was light yellow in color, bleached and unwaxed.  Peter Geraty (who steered me to this recipe) wrote that generally orange was the best shellac to use but that he didn't know if that applied to our purpose.

The recipe is this (Wehlte p. 217):

10g. borax  /  200 cc  water  /  30 g. bleached shellac
Disolve the borax in hot water.  Sprinkle in the shellac.  Do not boil.

Having 100 g of shellac I obviously increased all the quantities so that I could use the whole bag.  I took out my least favorite tool in my bindery, the hot plate, and went at it using my glass pyrex pan since I didn't know whether it was best to avoid metals when making this stuff (like one should do in making paste or methyl cellulose).

I kept the hot plate at half temperature (I think the hot plate that burned down the building I had just moved out of was probably set higher than that, but the fear remains!) and dissolved the borax instantly.  The shellac took probably 20 minutes of stirring to get it all dissolved.  I wondered what would have happened if I pulverized them in my coffee grinder (which I don't use for coffee, by the way) but I also wondered how long it would take to dissolve the marble sized pieces.  Seemed more therapeutic to stir and stir and stir.....

It came out this color:

Here is a picture of Fixor, which has been diluted 1:3 (Fixor : water) to its usable consistency:

I'd say it looks quite similar.  Obviously using a different colored shellac would result in a different color.  Again this was light yellow shellac.

But all that matters is whether it works.  I took a calf skin which I had dyed for tests on this.  In the right section I applied Fixor, in the middle of this image I flooded the space with this homemade fixor (I can't capitalize fixor if it's not the brand name Fixor, can I?  Too bad I'm not married to an editor.  Wait!  I am!)  The left section of this picture is two lighter coats of this homemade solution applied more carefully.  By this I mean that I used a cotton ball to spread the solutions over the whole part of the skin, not just in the impressions.

The surface of the leather after this application of Fixor and fixor didn't show much of a difference between them.

Looking closely at them anyone would have a hard time telling the difference between them, or deciding which was better to use.  These were all just a one strike impression, going back in would make them all more consistent and better.  If any section was worse than the other two it was the flooded section, which one wouldn't do anyway except to mess about.

A big, big thanks needs to go to Peter Geraty for pointing the way in this.  It's much appreciated.