All In A Nutshell
Paul Jarvis on good riddance to bad welds – part 4
THIS month we conclude the series on avoiding bad welds:
Rigid PVCu wall cladding is often used in conjunction with sheet vinyl flooring to produce an impervious easily-cleaned wall finish. In areas where hygiene is of high importance the joints between the sheets are
Whilst the methods for using the weld gun and weld rods are similar, producing a satisfactory welded joint requires slightly different techniques.
To achieve the best results, follow these guidelines:
• It is important that the two edges of the sheets forming the joint are flush with one another. This is achieved by fitting the sheets onto a 50mm double-sided tape
which is bonded to the substrate along the length of the joint.
• Unlike flooring, the sheets are gap welded. An even 1-1.5mm gap should be left between the sheets. Do not groove the sheets, but ensure that the edges are straight, crisp and clean.
• The weld rod is similar to that used for flooring, as is the welding gun. Because welding is carried out in a vertical plane, the work can be made easier and more comfortable if lightweight welding guns are used instead of the larger units generally used on floors.
• It is important to use samples on site to carry out test welds and set the welding gun to optimum temperature for the speed at which you wish to work.
• Ensure the area where you are working is clear to achieve a smooth even-paced run down the full length of the joint with the gun. This, together with ensuring the gap between the sheets is even along its length, will help achieving a weld which is even in its width and therefore more aesthetically pleasing.
• For cleaning off the weld I recommend using a trimming knife similar to that manufactured by Mozart (as opposed to the spatula traditionally used on floors) as this reduces the risk of damage to the wall panel edges.
The first cut is made with the sledge in place. The final is cut made by turning the sledge 90deg to the side and trimming the seam flush with the material.
• For best results, make the cuts in one continuous movement along the joint. To reduce the risk of marking the sheet, lubricate the base of the sledge and cutter with wax or similar. The reduction in friction will also make it easier to push the trimming knife, producing a smoother operation all round.
Lubricating the base, maintaining a sharp edge on the trimming knife, and cutting in one full length movement will avoid the need to go back on the weld to remove small pieces, giving the best chance of producing a smooth, even cut.
Paul Jarvis is a member of the Altro technical team.
T: 01462 489405
This article has been reproduced from the Contract Flooring Journal website. You can find them at www.contractflooringjournal.co.uk.