Author Topic: TOOL POST GRINDER BIT  (Read 686 times)

Offline Davis2x1

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TOOL POST GRINDER BIT
« on: January 11, 2018, 03:55:59 PM »
Just finishing up a tool post grinder for my Sherline lathe. I am using a Foredom hand piece with flex shaft to my Dremel tool. I am having trouble picking out what kind of bits to buy.  My first task will be to true up  my lathe chucks. There just too many types for me to understand. Is there a good "color", type and grit for "general" grinding of steel??

Thanks for your advice.
Dave
Dave
Sherline Mill and Lathe

Offline Florian Eberhard

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Re: TOOL POST GRINDER BIT
« Reply #1 on: January 11, 2018, 06:14:23 PM »
Hi Dave

Basically, you use aluminium oxyde (usually pink or white) for grinding hardened steel. What size of grit is difficult to say but I would use something around medium to fine. Not too fine if you need to remove quite some material and not too coarse for the finish.

Truing up the grinding wheel before grinding should help to get a better finish. With such small grinding wheels (and rather unstable conditions) it is useful to reduce the contact line of the grinding wheel to approx. 2mm. (otherwise the wheel will be just pushed away instead of grinding off the metal)

What is very important is using some lubricant for the finishing pass (I use Wd40, you can also use window cleaning fluid) because this gives you a pretty nice finish and the difference is quite big compared to not lubricated. It doesn't take a lot, you only have to get the steel and the grinding wheel wet (and put some again after each pass)

And finally: you will have to spark out a few passes with no feed for finishing.

Oh and this video may help you too:

Florian

Offline Davis2x1

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Re: TOOL POST GRINDER BIT
« Reply #2 on: January 12, 2018, 08:26:32 PM »
Florian,

Thanks for your reply. I tracked down some good information at grindtech.com. Their catalog shows the codes for the different shapes and compounds of bits. I helps when trying to search for a given bit. I can now go to MSC and filter out all but say the W171 or W188 type bits. It limits my choice to five or ten types.

Iíll post photos when the project is complete.
Dave
Sherline Mill and Lathe