When Mike told me about his mill table, I thought it was neat but I dismissed the idea of making one myself. Then while visiting another brewer friend (also Mike) I saw his mill, and happened to asked if he would mind sharing some details of the project. As an engineer I figured he’d have a well designed plan, and As I’ve found with most home brewers he was very willing to share details and helpful links. I wasn’t wront. Both times when seeing the powered mill setup, it didn’t seem necessary at that time. Then I used mike’s mill at the bow bog brewing party, and I was really impressed. It was very sweet to just dump in the grain and crank it up. Not that hand cranking is difficult, but it saves time and manual labor.
Once I took inventory of the required parts, I realized that I could build this with minimal investment. I had the mill, a motor, and I had a shelving unit I could use as the stand. It appeared all I was going to need to buy would be some sheaves (pulleys), a belt, a shim, and some miscellaneous hardware.
There are only a few variables in the project. You need to know the optimum speed for your mill, and most likely you’ll need to figure out how to convert your motor speed to that rpm. Which will require you to calculating which size pulleys to do that. I didn’t reinvent the wheel. I used the sizes recommend to me, and I used this calculator to validate the motor rpm, pulley diameter, and belt length. One thing to note is that the sheave will have an OD, but will have an effective belt pitch diameter, and that is what you use to plug into the calculator for the sheave diameter. Alternately if you want do the math yourself, it’s outlined very well in this PDF. That’s how I ended up with a 44 3l belt, a 10inch OD sheave, and a 1.5 inch OD sheave, converting my 1725 rpm motor to 188 rpm.
A mill table is a pretty simple contraption, it’s just a table with a mill and motor. The mill platform it comes with is a very elegant solution, the way it rests on the bucket it makes a nice seal minimizing dust. It has feet that locate it on the bucket and keep it in place while milling. I would need to be a superior designer to make something more elegant. Instead I tried to capture some of the features of the better mill mill tables I’ve seen. I built in a removable belt guard. Anytime there are spinning parts it’s a good idea to cover it. I added a shelf for the grist bucket, it has guides to ensure it is in the right place. I added curtains made from grain bags to two sides of the table. They allow access to the shelf below, but prevent some of the grain dust from escaping. The table has room for my grain scale and storage underneath for my foodsaver. While not more elegant than the platform, it’s certainly faster.
After having used it a few times, I’ve learned some of the nuances of my powered mill setup. I have to start the mill before filling the hopper. My hopper could be bigger. I make small, low abv batchs, and even then I need to fill the hopper multiple times. Milling is messy, even an elevated properly placed bucket results in a signficant amount of grain dust.
Here is a video, and some photos of the build process, and the finished product.