KRЯRL DЯAWINGS: Plate Preparation

There are certain basics that apply to all types of etching, from the plate preparation, to soaking the paper.

BEVELING

The edges of the copper plates must be beveled, to prevent the copper from cutting both the paper, and the expensive press felts. This is often done with files. However, in the Argos workshop, there is an easier way to bevel plates, by pulling them across sand paper.

Woodworker's Supply carries a heavy duty DeerFos sanding strips -- both 80 grit and 150 grit -- both of which were spray-glued side by side, to the heavy glass support. Glass is perfectly level, which is important to get an accurate bevel. (Hermes ceramic grit sandpaper might work better, perhaps).

Pulling the copper plate

across sand paper,

to bevel the edges

CONTACT PAPER

The back of the copper plate must then be covered in contact paper, so that the ferric chloride will not consume the back of the plate in the acid bath.

The back of the plate must first be cleaned with Bar Keeper's Friend, so that the contact paper will stick.

Once the contact paper is applied to the back of the copper plate, the excess must be trimmed with a razor blade. This is to prevent the contact paper from lifting.

The bubbles are rolled out of the contact paper. Any remaining bubbles may be pricked with a sharp point, to let the air out. This will not affect the copper plate.

DEGREASING

The front of the copper plate must first be degreased before applying the grounds. If there are any fingerprints, or other oily residue, the grounds come off, even slightly, in the acid bath, and ruin the etching.

Lye dilution:

1/2 ounce (or 15 grams) per 2 cups dispenser

or, 1 ounce per quart used (.66 ounce would classify as "non-corrosive")

Household Drain Opener

is lye

The first step is to rub the plate with chalk and a very weak solution of lye.

After washing that off, sprinkle Bar Keeper's Friend over the plate, and clean the surface again.

Dry the copper plate immediately (perhaps by rolling a Bounty towel roll over it), so that the copper does not oxidize.

BOUNTY tip: roll a roll of Bounty over the wet copper plate to dry it.

Drying the copper plate with Bounty towels

FERRIC CHLORIDE

The "acid" we used to etch the copper plates was Ferric Chloride. This was poured into a flat tray.

After 15 minutes, the plate may be taken out and washed in a solution of vinegar, and then in a separate tray of water. This is done to clean any precipitate that might fall into the etched lines, and prevent them from further etching. This may not be a necessary step.

Salted Vinegar bath

ELECTROLYTIC ETCHING ALTERNATIVE

We did not do any electrolytic etching in this workshop (YouTube video), but I did find a simple electrolytic etching method on YouTube, using a 9 volt battery and a Q-tip:

Etching with electricity

CLEANING GROUNDS AND INK

The traditional grounds may be cleaned off the plate with environmentally friendly

"De-Solv-It -- Contractor's Solvent," from Ace Hardware.

De-Solv-It will also take off the ink, after the plate is printed.

This EZ Strip from Home Depot, easily takes off the BIG grounds.

SOAKING THE PAPER

Before printing, the paper must be soaked first, for at least 20 minutes generally. This is to make the paper more supple, so that it can better be pressed into the depressions that hold the ink, when running the paper over the plate in the press.

After soaking, the paper is placed between two blankets to take out the excess water. One also rolls a brayer over the blankets, letting the pressure squeeze out more water.

FLATTENING THE PRINT