Our goal in these first trials was to achieve a full, complete transfer of the printed film areas to the copper plate. We followed the directions of Techniks Inc exactly, in order to gain a sense of the nature of the film itself.
Date: March 22, 2013
Researcher’s Name: Liz Bannish & Stephanie Gaumond
Plate Material: Copper .032
Plate Size: 5.75 x 4.5″
Room Temperature: 69 degrees F; low humidity
First we backed the copper with transparent Contact Film and cut the plate into smaller 5.75 x 4.5″ plates. We beveled the edges with a file. We polished the surface with 00 grade Brillo pad and degreased it with a 1:1 ratio of soy sauce and water. We patted it dry with newsprint.
To prepare the film we first drew a line image and scanned it with an Epson 836XL scanner. We chose to begin with a line drawing in an attempt mimic its intended use for homemade circuit boards. We scanned the drawing with a resolution of 300 and scaling value of 9 out of 2133. We then imported it into Photoshop CS2. The drawing was duplicated as to have four printed per 8.5 x 11″ sheet.
We printed our duplicated drawings on the matte side of the Press-n-Peel PCB transfer film with a Brother HL228-ODW laser printer. In order to adhere our separated drawings we heated an iron to 275 degrees Fahrenheit. With a piece of newsprint between the iron and the plate we ironed the film – image side down- onto the degreased copper plate. We applied direct heat for 2 minutes, the minimum according to the Tecknicks factory directions. After our 2 minutes of direct heat we ran the plate and attached film under cool running water for about a minute and peeled off the film.
Our image did not completely transfer. In an attempt to get a complete image transfer we tried another of our drawings printed from the same sheet and another plate prepared identically. We decided to alter nothing except lengthening the duration of time we ironed the image. The iron temperature was at 279 degrees fahrenheit and an ironing time of 3 minutes as opposed to 2 minutes. We rinsed the plate with cool water for about a minute. With this test, less toner was left on the transfer sheet but again, not a complete transfer. Concern arose about surface oxidation as the cause of the incomplete transfer. We then decided we would attempt to get a complete film transfer before etching the plate.
The third attempt we decided to alter the size of the newsprint to the same size of the plate exclusively so we could accurately see where the plate ended, therefore being able to apply direct heat to every part of the plate. We increased the temperature of the iron to 300 degrees Fahrenheit. We rinsed the image as before after 3 minutes and got a nearly complete transfer. With the last drawing from our printed sheet of transfer film we kept the temperature at 300 and the time at 3 minutes but after degreasing the plate with soy sauce and water we then immediately deoxidized the copper plate in a solution of salt and vinegar for 10 seconds before rinsing with water. After heating the plate for 3 minutes we again, ran in under cool water and peeled the film. Incomplete transfer. We decided to etch the plate with the largest amount of transfer from the PCB film.
Etched in Ferric Chloride in a vertical tank at 40 degrees Baume.
Timed Application of Mordant
We etched the plate for 21 minutes.
Removal of Grounds
The PCB film was removed with a 00 gauge Brillo pad.
After Bath Evaluation
The open areas of copper open bit as to be expected due to the lack of any sort of aquatint. The film became lighter in color and opaque.
We used Bone Black Etching Ink #541 by Graphic Chemical. We wiped the plate with tarletan only.
Paper Type: Hahne muhle
Paper Soaking Time: 10 minutes
Press Blanket Setup: Takach press, 2 sizing catchers, 1 newsprint, pressure 6
Based on the trials, our first goal is to obtain a successful, full transfer of the film. Higher temperature and longer application proved to be more successful in transferring. After the suspected oxidation problems we concluded that the oxidation of the plate did not play a role in the film transfer. The width of the lines were consistent to the original drawing after etching proving the film proved to retain the integrity of the image. That being said, we did not achieve a pure white tone where the film was applied. Further buffing of the plate and the integrity of the film as a complete stop out may be considered in the future when attempting to use the film with images with complete tonal range.