I often read of folks having grain get past their domed false bottoms used with Rubbermade coolers and plugging up the down stream works. The causes are usually due to a less than truly flat FB or a warped liner, or inadvertent movement of the FB while stirring the mash.
One tip has been to split a length of tubing cut to the circumference of the FB and slip around the edge, to take up the gap between FB and cooler liner. I gave that a try with a couple of types of tubing but in both cases the fit was less than impressive, and the tubing was too firm to really mold to the liner anyway.
A couple of weeks ago while in the grips of the flu I came across another mention of the grain/FB problem, and it inspired me to get onto the Mcmaster site and wade through their listings of silicone gaskets, looking for a profile that would work. I found a couple of contenders (at the bottom of this page
) and ordered four feet of both.
The strips arrived and languished in my shop 'til body and soul were resurrected - which brings us to this morning.
I pulled my 12" domed FB out of my 10G cooler and laid everything out. Shown is the smaller of the two types of stripping I received.
I immediately realized the smaller type wasn't going to bridge the gap between the edge of the FB and the cooler liner, so I moved to the larger stripping (Mcmaster part number 12335A63). After giving it a good soap and water wash in the sink I cut it to just make it around the FB and held it in place with a piece of tape. You can see the gasket profile in the small piece at 10 o'clock.
I sprayed the liner with some water as lubricant and slowly worked the FB down to the cooler floor, pulling the tape off along the way. Once the FB rim hit the bottom I massaged the gasket as far down as it would go, holding everything tight together down there.
I obviously haven't had a chance to give this a real test drive but it sure looks promising. There's plenty of flexible "lip" in the gasket profile to take up sidewall distortion as the liner ages, and that FB isn't going to move a lick even if it gets nailed by a mash paddle. And being silicone it's not going to have any issues with the mash...