Here is a nice cover my wife reluctantly made for my PowerTig 200DX welder. It's made from dark green "Duck Canvas" from the local JoAnn Fabrics store. I believe I paid about $10.00 for the material which was on sale and is quite nice. I believe I purchased 1 1/2 yards.
Dimensions for the fabric pieces:
Quantity 2 Side panels 18" X 22.5"
Quantity 2 End Panels 13.5 " X 18"
Quantity 1 Top Panel 13.5" X 22.5"
The above dimensions make a fairly roomy cover with about 0.25 inch for the seams and 1" turned under on the bottom edge.
You can cut the two sides and two ends in one shot by folding the cloth in half and then splitting it when you are done. It's much easier to convince someone to sew the pieces together if you cut the pieces yourself!
Link to material:
http://www.joann.com/joann/catalog/p...RODID=prd23683