design of crushgrind based Peppermill

[Bill Dempsey]

I'm ready to start making 6 mills for holiday gifts, all based on crushgrind (or Woodcraft clone) mechanism. In the past, I've always included a mortise and tenon of various designs between top and mill body. Craftsupplies has an instructive video which simply uses the 1 1/16 body bore as mortice and the "base" of the mill head crush grind mechanism as the tenon. Of course, this method greatly simplifies the build, but ??. If the roughly 1/8 "tenon" length is insufficient in daily use the mill is NG.

Anyone with experience?
thanks, Bill
https://blog.woodturnerscatalog.com/2016/11/turning-crushgrind-mill/

[John King]

Don't even consider making a salt shaker, pepper mill, etc. until you get (and read) a copy of Turning Salt & Pepper Shakers And Mills by Chris West. There's a section in the book dedicated to the CrushGrind@ mechanism. Everything you need to know.

You don't need a "kit". Buy CrushGrind mechanisms (see Packard Woodworks at https://www.packardwoodworks.com/153201.html?Category_Code=). Pick your favorite wood (3"x3"x12") for the mill body and cap and turn the exterior to the shape that you desire.
Some photos of my work:

https://www.aawforum.org/community/data/attachments/37/37518-e27fb9ad76dde616cfcc8f362692bca1.jpg (https://www.aawforum.org/community/attachments/suzie-salt-mill-1st-place-september-2015-gcwa-jpg.40200/) ______ https://www.aawforum.org/community/data/attachments/37/37519-c53ecdac0f5c662f693c5c00c6cf0d2f.jpg (https://www.aawforum.org/community/attachments/julie-and-leslie-salt-mills-1st-place-july-2016-gcwa-jpg.40201/)

When properly installed, the CrushGrind@ mechanism requires no epoxy or similar adhesive. Here’s the deal.

Most, but not all, instructions for making CrushGrind@ mills provided by US suppliers specify 1) a 1⁹/₁₆” diameter hole in the mill body for the grinding mechanism, 2) removal of the spring clips from the grinding mechanism and 3) use of epoxy (or similar) to secure the grinding mechanism in the mill body. These same instructions specify 1) a 15/16” diameter hole in the mill cap for the stopper, 2) removal of the spring clips from the stopper and 3) use of epoxy (or similar) to secure the stopper in the mill cap. One can make a very nice pepper/salt/spice mill using these instructions. But there is a better way! It’s the no epoxy-required way.

The manufacturer’s recommendation for the diameter of the hole in the mill body for the CrushGrind@ mechanism is 38mm (1.496”). I am good with calling that 1½” (1.500”). The manufacturer’s recommendation for the diameter of the hole in the mill cap for the stopper is 22mm (0.866”). I am good with calling that 7/8” (0.875”).

No epoxy (or similar) is required to secure the grinding mechanism in the mill body and the stopper in the mill cap if 1) the CrushGrind@ manufacture’s recommendations for the mill body and mill cap hole diameters are used and 2) a groove is cut in the mill body and the mill cap to accept the spring clips on the grinding mechanism and stopper.

Sorby makes a groove cutting tool for CrushGrind@ mechanisms. It's available on Amazon at https://www.amazon.com/Robert-Sorby-895CGH-Crush-Grind/dp/B00JMJKML2 (https://www.amazon.com/Robert-Sorby-895CGH-Crush-Grind/dp/B00JMJKML2). It’s a must-have tool if one is going to install the CrushGrind@ mechanism in pepper/salt/spice mills using the spring clips and no epoxy.

With the grinding mechanism and stopper press fit into the mill body and cap, respectively, and the spring clips lock into the mill body and cap grooves, epoxy is not required for a secure fit.

An excellent set of instructions for making a pepper/salt/spice mill using the CrushGrind@ mechanism can be found in Turning Salt & Pepper Shakers and Mills by Chris West, “Drilling and Fitting a CrushGrind@ Mechanism,” p 132.

In my opinion, the CrushGrind@ mechanism is far superior to the stainless steel grinding mechanisms. It can be used to grind pepper, salt and spices. The grind can be adjusted from coarse to very fine. It’s made of non-corrosive ceramic. There is a 25-year guarantee on the ceramic parts inside the CrushGrind@ mechanism.

Give it a try. I think you will like it. – John

PS - The Sorby groove cutting tool is notched to register the correct depth of the groove in the mill body. It is also etched for the correct depth of the groove in the mill cap. - J

[Walter Mooney]

Bill, if you go to Woodcraft to buy your mechanisms, check out their wood blanks. Believe it or not, they sell a pre-drilled blank for their mechanism for about $40, while a comparable blank, not drilled, is ~ $50! Don’t ask me how they do it.

[Tony Rozendaal]

To answer the question in the original post, I have made Crush/Grind peppermills without using a tenon and with using the tenon - I like making a small tenon the best. It not only gives a slightly better feel (in my opinion) to the fit of the stopper, it gives me a method to hold and drive the stopper for the final shaping and sanding of the top.

Also, in my opinion, the 1-1/2 inch hole will work for the mechanism if the blank is perfectly dry. If there is any movement at all in the wood after the hole is drilled, the 1-9/16 hole is better. It is very disheartening to ruin a $15 mechanism while pressing it into a hole which is slightly too small. I speak from personal experience.