Wedgewire Specifications

[orangehero]

Hello,

I'm trying to figure out the ideal specifications for wedgewire for a mash/lauter tun false bottom. I've seen recommendations from 0.50 - 1.00 mm (0.02 in - 0.04 in) slot spacing, but that seems tight to me as I've only used perforated false bottoms. I'm not sure about the specs for wire width and open area percentage.

I'd appreciate any suggestions.

Thanks in advance!

[orangehero]

Does no one use wirewedge?

[gcbeer]

wedgewire.com

try these guys - http://www.wedgewire.com/

[dick murton]

0.7 mm is what I have been used to, so 0.03" looks about right. From memory, about 9% surface area as the slot area at the top of the plate for wedge wire plates. Milled plates have a somewhat lower slotted surface area - i think a bit less than 7%

[gitchegumee]

It's not a simple answer. Refer to page 290, figure 95 of DeClerck's Textbook Of Brewing, volume I; and page 327, figure 11.5 of Malting And Brewing Science , volume I. These show the most common lauter slot designs.

[CraftBeerIndia]

Open Space %

The standard across suppliers seems to be 0.7mm spacing on false bottom plate.

The other issue is total open space. Taking 100% as your false bottom plate, <40% open space would be the total area of the plate which is open (slots) to allow wort to filter through. If it's too little then expect slow run off and other problems. If it's too much then expect clarity issues and other problems.

Final issue is loading on the false bottom which is rated at kgs per cubic vol. This will vary depending on the size of the tun. This determines how much grist you can hold on top of the false bottom plates, how thick the plate needs to be, etc...

Sizing and fitting false bottom plates is very critical and requires a fair amount of skill and experience...suggest to leave it to a professional brewery engineer (not me!).

[dick murton]

I'm obviously well out of date or suffering from Alzheimers - my estimate of 9% is woefully low - reminder to self to look up a few things before glibly answering.

For what it is worth, the following link to a pdf of wedge wire spec (20 to 30 % free area) is probably a pretty good example of the sort of thing sold for lauters. https://www.trislot.be/files/pdf/app...%20english.pdf


But be careful to ensure the plates are stong enough to walk on regularly if that is what is required. Higher free surface area will mean they are less suitable for manually digging out by standing in the tun on a regular basis.

I think my guesstimate of 7 - 9% was based on old British mash tun plates where the operator stood on them to finish cleaning out at the end of every brew. And possibly of gunmetal (bronze) not stainless, bronze being much weaker so requiring less free area to ensure adequate strength.

[gitchegumee]

Dick, I think your memory serves you well. DeClerck recommends open area of 6-8%. Briggs, Hough, Stevens, and Young 11%. Premier quotes 15-20%. Ripley
stainless 12%. Briggs 10%. The high quality milled lauter bottoms I've seen are much less open than solid.

[dick murton]

Thanks Phil

[orangehero]

Thanks guys I appreciate the help and information!