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Anodyne
17th January 2012, 11:37 PM
Hi, I am about to order some Colt drills and am looking to make some pepper mills, with the Crushgrind inset.
The Crushgrind webpage has instructions that are not the same as the drawing, also there is no mention of the retaining groove although it is in the drawings.
The drawing has 44mm, 38mm, 25mm and 22mm wheras the instructions use 45mm, 38mm, 20-25mm and 35mm. I don't want to purchase unnecessary drills, can anyone advise the correct set?
Also is the Sorby tool for the groove worthwhile? It's been a while since I've done a peppermill.
Thanks

Dalboy
18th January 2012, 12:02 AM
Hope this may help.

Roger C
18th January 2012, 06:00 AM
:UHi Anodyn I have made many mills using crush grind drills, needed are a 44-45mm not important which, 38mm this is IMPORTANT. 26mm this is for the small white thing a ma jig that fits on shaft and in hole on top. Send me your email address and i will draw a thing on excel and send it. It is night here now 2100hrs 17/01 but will check mail at0600 18/01 Cheers Roger in RSA:U

DoctorBobski
18th January 2012, 06:45 AM
Hi Anodyne. In the first colt group buy I ordered only for the purposes of making crushgrind grinders. I got the following and haven't been disappointed.

22mm
25mm
38mm
35mm
44mm
No. 2 MT Rotastop adapter

I also ordered all three extension sizes but have only used the 90mm one for the standard length crushgrind mechanism.

As for the recess I use the Robert Sorby tool (http://www.cws.au.com/shop/item/robert-sorby-crushgrind-relief-cutting-tool) with good results.

Hope that helps.

RETIRED
18th January 2012, 06:55 AM
Or, you could use this.CWS Store - Woodcut Mill Drill | Carroll's Woodcraft Supplies (http://www.cws.au.com/shop/item/woodcut-mill-drill)

Anodyne
18th January 2012, 11:34 PM
Thanks guys for the responses. I wasn't aware of this product, and will have a further look. Thanks to Doctor Bobski for the info, by the way are you medical? Finally thanks Roger C- I've sent you a PM.
This forum is great for the depth of knowledge of its contributors, and their willingness to help. A further thanks to the moderators who keep it all nice and shipshape, and finally a thanks to the sponsors, without them it would surely fold. This is the best organized and useable woodworking forum on the web

DoctorBobski
19th January 2012, 06:41 PM
Thanks to Doctor Bobski for the info, by the way are you medical?Doctor first and wannabe woodworker second. I also looked at the woodcut mill drill but decided that the forstners would be more versatile for other projects.

rsser
22nd January 2012, 03:16 PM
Sawtooth and forstner bits take a bit of skill to sharpen. If you go for the Colt HSS bits be prepared to work with diamond paddles and rods.

The MillDrill looks much easier to sharpen but I have yet to do one.

Declaration: no connection, either financial or social, with WoodCut or Colt.

brendan stemp
24th January 2012, 09:23 AM
My MillDrill has now helped me make hundreds (literally) of crushgrind mills. Worth the outlay if you plan to make a few grinders. I reckon grinders are one of the best things woodturners can make for all sorts of gifts so its worth learning to make them and therefore worth buying the MD. It replaces 2 drill bits; 38mm and 45mm and also gives you the exact depth and distance between the two holes needed.

It is a versatile tool that can perform other drilling tasks so it not soley for crushgrind mills. THe cutters can be adjusted easily to cut a wide range of hole sizes. I know all this because I designed the tool and trialled the first prototype which I still use. I also wrote the instructions for the tool and when you buy a MD it also comes with instructions on how to make the mills.

The second part of your question: the Sorby tool, I use mine all the time. It does the job well but I know a lot of people make their own. I initially used a ground down old skew chisel. The only concern is getting the groove at the correct depth. Easily done. The Sorby tool has marks on it that indicate the correct depths the grooves need to be cut at. So it's a matter of whether you want to outlay the money for the tool to do only 1 or 2 grinders or you plan to make lots. If you think you might make lots of grinders and you don't have any spare steel to make the tool then I would suggest its worth the expense.