How to Build a Mash Tun Filter With Copper Pipe

A copper mash filter will make your homebrewing simpler.

A mash tun is used in homebrewing to separate fermentable extract (wort) from a mixture of grain and heated water (mash). Similar to allowing tea to steep, mashing allows enzymes to modify the hot mash. Once mashing is finished, the wort must be filtered out for fermentation. Copper is the preferred metal in brewing, so making a mash tun filter out of copper tubing will make you the envy of your homebrewing community.

Things You'll Need

• Insulated mash tun measuring at least 12 inches square on the inside with draincock installed
• 4 feet of 5/8 inch o.d. copper tubing
• 4 copper elbows, 5/8 inch i.d.
• 3 copper tees, 5/8 inch i.d.
• Pipe cutter
• Measuring tape
• Drill
• 5/16 inch drill bit
• Ball peen hammer
• Flat file
• Short piece of heat resistant 5/8 inch i.d. flexible plastic tubing

Instructions

1. Using the measuring tape and pipe cutter, measure and cut two 10 1/4-inch lengths of copper tubing. Cut 4 pieces 3 1/8 inches long. Cut two pieces 4 3/4 inches long. Finally, cut one piece 2 inches long.

2. Assemble the filter. Keep in mind that the finished filter will be square. Take one 10 1/4-inch piece and attach elbows to each end. In each of those elbows, insert a 3 1/8-inch piece. Attach a tee to each open end, and insert the remaining 10 1/4-inch piece into the short end of the two tees. Insert a 3 1/8-inch piece into the two open tee ends, and then cap the end of both pieces with the two remaining elbows. Examine the two 4 3/4-inch pieces, and insert them into the elbows. Complete the square by inserting the one remaining tee into the opening, with the short end of the tee facing out. Insert the 2-inch piece into the tee. Tap everything into place with the hammer.

3. Drill the filter holes. Place the assembled unit on a block of wood and drill as many holes as you deem necessary. Drill through the pipe. Remember that holes on the bottom of the filter will help extract more wort.

4. Clean the filter. Using the file, remove any burrs or other sharp edges. Rinse the filter and then insert the unit into the tun. Attach the filter to the draincock using a short piece of 5/8 inch i.d. heat-resistant plastic tubing.

Tips & Warnings

• Leaving the filter unsoldered will allow you to disassemble it for cleaning. Measurements are specific to a 12-inch tun, and should be modified as necessary to fit your own equipment.

• Drill carefully. Always wear adequate protective gear.

References

• John Palmer; How to Brew; How the Mash Works