And finally .................... details of my 70L stainless steel boiler. Like my 50L boiler (see earlier post), this sits on a SS skirt 2mm thick x 100mm high. However, unlike the 50L one, there is no 'lid' attached to the top of the skirt for the pot to sit on. The 70L pot is mechanically bolted to the skirt in four places: at each side by the heating element mounting holes and back and front by stainless steel blanking plugs and SS 3mm x 25mm bars. The skirt diameter is slightly less than that of the bottom of the pot itself, whose diameter increases slightly towards the top of the pot. The sealing washers are food grade high temperature fibre washers from BES and provide totally watertight seals. I found that the bottom of the pot was quite wobbly as the thickness is only 1mm at most. I therefore added an extra bottom to it. For this I used a redundant aluminium hop strainer that I originally made to sit at the bottom of a converted Baby Burco. As a hop strainer it never worked particularly well and was set aside waiting for a rebirth! I drilled a 1 inch BSP stainless steel lock nut with three small holes and bolted this to the middle of the hop strainer. Into this I screwed a couple of 316 SS parallel nipples and full sockets to give an extra central leg to support the pot when full and prevent the pot bottom sagging under a full load. This middle support also acted as a method of holding a 0.9mm thick SS covering bottom to the pot by using a 1 inch BSP plastic locknut. Expanded foam was used under the cover to provide insulation. The old hop strainer was fixed to the bottom of the pot with a really thick layering of JB cold weld. A sight glass was added and a 1 inch SS ball valve bolted through the skirt to provide bottom drainage. The drain hole itself is a 1 inch BSP SS marine skin fitting with slots cut in to aid drainage. All plumbing fittings are 316 SS from BES. The usual Backer old-type kettle elements are used, again with stainless steel shrouds. I started off using M40 bearing nuts, but found that they were rusting, so bought the shrouds.
Last edited by chastuck on Wed Apr 03, 2013 6:07 pm, edited 1 time in total.