For the structure, i needed it to be made of some sort of metal, as wood, would not be able to support the weight of the 6mm Perspex sheets, with out them warping. Aluminium would have been practical due to its lightweight qualities, but it was too expensive and didn’t quite fit the aesthetic had in mind for the over all feel of the structure, so instead, I used steel.
After talking with several different metal workshops on site and off, i realised that i would need to use steel angle at 5mm thick, in order for a strong overall structure, and so that it would be able to take the weight of the perspex. I chose 50mm steel angles so that there would be room for the 6mm thick perspex, and also that it would look as well as be sturdy and industrial.
Me practising to weld on scrap steel
I sourced and chose to weld my steel angles from a ware house in North London, at a friends recommendation. This way i managed to get time with one on one training with the welding equipment and staff. As well as benefit from a discount on the raw materials, it made sense to make these vast frames off site where i had more room and more of a flexible timing.
Above is my first attempt at welding two sides of steel angle. I wanted to get used to the process and materials before i worked on the larger and more costly steel. Here you can see the welding marks, which i realised i couldn’t have on the actual frames. Not only because id rather it be smooth in terms of looks, but also, i needed the surface to be as flat as possible so that the perspex would sit with out tension on the frame and be suitable to silicon in place.
Then i was allowed to practice on some smaller parts of scrap steel they had in the warehouse. Here i was able to ensure i developed the right technique when it came to the actual frames i was to use. First off, i cut [with an angle grinder] the steel angles at 45 degrees at the correct length, then weld them together and finally used a steel buffer to shave and smooth off the excess from the welding.
To ensure the angles were exact we used a steel square.