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Friday 8 November 2013

Photo Etching and Embossing Induction

As part of the Design for Print brief, we have to try as many different techniques that we can to inform our practise. From this, we have been given the chance to have an induction in Etching and Embossing.

There are some things that we need to take on board when considering and doing this process:

  • Not to use material that is too thick as the paper will not sink into it and emboss properly. The material we are printing onto must be softer than what its being printed from.
  • Images should be silhouettes so it prints as one whole image rather than detailed bits of an image- more likely to create a successful print
  • You don't want Fonts to be smaller than 10/12pt or be Serif as it makes it difficult to read and more likely to go wrong. 
  • It usually a good idea to do it in the morning as the copper plate itself takes 7hrs in the solution and needs turning halfway through. If forgotten about, it can ruin the plate as the solution will eat away at it.
  • Your copper plate must be bigger than your actual design to prevent any marks and indentations transferring onto your design.
The main thing to remember is:
  • Embossing is best done with a copper plate as it is thinner and can make a sharper, cleaner emboss
  • De-bossing and Indentation is best done with a laser cutter as it is much faster

From this, we went onto being shown the process of Etching to make a plate for Embossing:

Sand Copper Plate
The first thing you do with your Copper Plate is you sand it down using the Belt Sander to make it all smooth on the side your going to put your design on as it makes for a smoother transaction and gets rid of any marks or imperfections which could effect the quality of the print.

Degrease Plate
After sanding, the plate needed to be degreased in the sink, getting the excess off the plate so that it was clean from any debris. This also allows for you to see if there are any bits that you've missed sanding.
Blotting Copper Plate
You then need to blot your Copper Plate dry using newsprint.

Light- Sensitive Film
The next part of the process is to cover the Copper Plate in a light-sensivtive film so that the design can be transferred. The film is made up of 3 layers: a frosted layer, a protected layer and the exposed layer.
Placement of Film
When placing the film onto the plate, you need to make sure that it is flat and occurs no anchor points.



Plate Through the Press
We then placed it onto the plate, put the blankets over and ran it through the Press. After going through, we turned the Plate 90 degrees and ran it through the press again so the film will be firmly stuck to the Plate. We then cut around the plate to take off the excess material. At this point, we took the plate over the to the Lightbox to transfer the image and exposed it for 8 light units. Due to the copper being exposed to the light, when the cycle had finished, the metal was earthed. When doing this technique, you don't need to flip the text on the design as the exposure will flip it for you and put it right when its been printed.

After being exposed, we created a solution made of a 10g spoonful of Sodium Carbonate and water of 24 degrees approximately 3 jugs full.


Preparation of Solution
The protective layer of the Copper Plate is removed and the plate is put into the solution where it is bathed with a sponge every 30 seconds which gets rid of any excess film.

Cleaning Excess Film Off
You can tell if there is still some excess film left over because there will be some bubbles on top of the surface of the print. You need to keep washing it until all the bubbles are gone, which can take up to 10minutes worth of washing. This over-exposure shouldn't be a problem to the overall design.

Taping the Plate
The print is then rinsed clear of the solution, blotted dry and put in the Print Screen room for it to quickly dry. It is then exposed once again in the Lightbox. When dry, the back is tapped up to hold the design together for when it is put into the acid. There must be no mistakes when putting the tape on the back and it must be all flat.

Handle attached to Plate
A piece of plastic is tapped to the back of the plate and used as a handle so that it is easy to put in and out of the acid.

Acid for Plate
When the plate is put in the acid, it is left there for 7 hours, however, it must be removed at the crucial moment otherwise it will burn through the plate. The plate needs to be rotated after 3 and a half hours otherwise the acid will make the plate lob-sided.

As our plate would not be done in that time, Neil got a plate that had already been produced and showed us how to Emboss using the Plate. Making the Plate takes a long time but the actual process of Embossing is very fast and quick.

Copper Plate ready for Embossing
The Plate is put onto the board along with the stock that you want embossing and then bulked up with Tissue Paper before being put into the Hydraulic Press.

Hydraulic Press
Pressures of the Hydraulic Press
The Press has 2 setting which are Low Pressure and High Pressure which can be determined through pressing a button to the side of the handle. Using the handle, the Press can be hand-pressured using the Low Pressure setting before it gets very stiff and difficult to pump. Pushing the Button down and applying the High Pressure setting will let you continue pumping, with you aiming to get it at 5000 pressure per square inch. Your plate needs to be in the centre of the press to prevent a tilt to the emboss. When you have applied the pressure for the print, you release the button which will funnel all the water back to the pump and relive it off the pressure.

Emboss Results
 As you can see, the emboss thats been created is very clear and defined.


Mountboard and the Emboss Result
Wood and the Emboss Result
You can achieve this effect with mount board and wood which have been laser cut with the design of your choice but it doesn't give as much of a defined emboss. The thinner the material, the deeper the emboss. For a de-boss, this material would be better suited.

I felt that the overall technique was good to learn as Embossing can give your work the look of better quality. This workshop has inspired me to organise a Laser cut Workshop so that I would be able to learn how to emboss and de-boss with that technique as well, giving me a range of methods to work from.

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