Acid Etched Flashed Glass #1: Safety and setup

Properties & Qualities

Qualities

2D, Colourful, Textured / tactile, Translucent

Sample Information

Date

12/06/2023

Dimensions

1900mm x 650mm x 4mm

Weight

20kg

Culture & Context

In the United Kingdom, Hydrofluoric Acid (HF) is classed as a hazardous substance, therefore the Control of Substances Hazardous to Health Regulations 2005 must be complied with. You are required by the Regulations to undertake a risk assessment of the activity in which Safety is vital when considering acid etching and should only be undertaken after appropriate training, used in the correct environment and the use of personal protective equipment. Because of the free form nature of the glass I prepare, I do not use a closed fume booth but use a designated room that has air extraction that creates a negative pressure environment. This ensures no vapours remain in the room after the process has completed. I also use the appropriate standard of rubber long length gloves, rubber apron and full face respirator mask fitted with chemical vapour filters. I undertake a full check of all environmental and PPE safeguards before starting any etching work.

Due to the highly corrosive nature of the HF, I store calcium gluconate gel in the studio’s first aid kit.

I use an LED lightbox as my working surface. Not only does it illuminate the work well when I am working on it, but it is also easy to wash down afterwards.

I regularly use paint brushes to apply acid, however, the acid id will gradually destroy the metals on the paint brush, so it has been prepared with bitumen paint. The bitumen is a resist, and in its liquid form it can be applied into the bristles around the brush ferrule, and over the ferrule itself.

I also use plastic contains, such as paint roller trays, to contain the acid in a small bath. This allows the glass to be fully submerged into the acid.

I usually use the acid etched process when working with flashed glass. Flashed glass typically consists of two colours, the base layer and the flashed layer, both of which are fused together during the glass blowing process.
The base colour is usually about 3mm thick, and the flashed colour is less than 0.5mm thick. By removing or etching away the flashed colour the base colour can be revealed. This can be achieved by several etching methods, however acid etching allows two benefits; the revealed base colour retains its transparency and the flashed layer can be removed gradually andresult in gradations of colour. F will be used, before the activity commences.

Process & Production

Safety is vital when considering acid etching and should only be undertaken after appropriate training, used in the correct environment and the use of personal protective equipment. Because of the free form nature of the glass I prepare, I do not use a closed fume booth but use a designated room that has air extraction that creates a negative pressure environment. This ensures no vapours remain in the room after the process has completed.

I also use the appropriate standard of rubber long length gloves, rubber apron and full face respirator mask fitted with chemical vapour filters. I undertake a full check of all environmental and PPE safeguards before starting any etching work.

Due to the highly corrosive nature of the HF, I store calcium gluconate gel in the studio’s first aid kit. I use an LED lightbox as my working surface. Not only does it illuminate the work well when I am working on it, but it is also easy to wash down afterwards. I regularly use paint brushes to apply acid, however, the acid id will gradually destroy the metals on the paint brush, so it has been prepared with bitumen paint. The bitumen is a resist, and in its liquid form it can be applied into the bristles around the brush ferrule, and over the ferrule itself. I also use plastic contains, such as paint roller trays, to contain the acid in a small bath. This allows the glass to be fully submerged into the acid.I usually use the acid etched process when working with flashed glass.

Flashed glass typically consists of two colours, the base layer and the flashed layer, both of which are fused together during the glass blowing process. The base colour is usually about 3mm thick, and the flashed colour is less than 0.5mm thick. By removing or etching away the flashed colour the base colour can be revealed. This can be achieved by several etching methods, however acid etching allows two benefits; the revealed base colour retains its transparency and the flashed layer can be removed gradually and result in gradations of colour.

Recipe Details

Hydrofluoric acid is subject to sales controls and can only be purchased through specialist suppliers. It is normally sold at 60% strength. This strength is very powerful and too strong for the most glass etching processes. As such, it requires to be diluted to working strengths. I normally prepare batches of 40% and 20%. This is achieved by diluting with water. The volumes of water and acid are measured and mixed.

It is important to add the acid into the water, and not the other way round as water being added to acid can cause the water to boil and create more hazardous conditions. All acid mixes are stored in suitable plastic bottles and kept in a secure cupboard, which has clear hazard warnings visible.