Tool Bit Grinding

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Mr Ron
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Joined: Tue Dec 22, 2009 12:36 pm
Location: Vancleave, Mississippi

Tool Bit Grinding

Post by Mr Ron »

Adapter recess detail.jpg
I just got around to making grinding wheel adapters so I can use surface grinder wheels on a bench grinder. Everything went along smoothly until I got to the recess in the flange. Question: How do I grind a bit so I can get into the recess?
Mr.Ron from South Mississippi
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NP317
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Re: Tool Bit Grinding

Post by NP317 »

I suggest you grind a HSS tool like a cut-off blade, but at a 45 degree angle. I've made such tools for the same operation you want to do.

Another suggestion: Place the holes for the shaft-locking screws on opposite sides of the adaptor, for better balance.
~RN
Mr Ron
Posts: 2126
Joined: Tue Dec 22, 2009 12:36 pm
Location: Vancleave, Mississippi

Re: Tool Bit Grinding

Post by Mr Ron »

NP317 wrote:I suggest you grind a HSS tool like a cut-off blade, but at a 45 degree angle. I've made such tools for the same operation you want to do.

Another suggestion: Place the holes for the shaft-locking screws on opposite sides of the adaptor, for better balance.
~RN
Thanks. Actually I plan to use setscrews at 120° apart for centering the adapter on the shaft.

Is this what you mean?
Recess Bit.jpg
Recess Bit.jpg (6.42 KiB) Viewed 2343 times
Mr.Ron from South Mississippi
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Harold_V
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Re: Tool Bit Grinding

Post by Harold_V »

When grinding a tool for that type of cut, keep in mind, the right hand (side) relief must be extreme, as you must also allow for the radius of the cut. The smaller the cut diameter, the greater must be the relief.

The tool need not have the 45° angle----a simple tool ground like a parting tool, with proper relief, will work just fine, although you'd want the cutting edge offset on the left hand side instead of the right hand side. For folks who don't have the option of random angle setting with their tool post, that eliminates a problem.

Harold
Wise people talk because they have something to say. Fools talk because they have to say something.
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NP317
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Re: Tool Bit Grinding

Post by NP317 »

Yes. The tool drawing is what I had in mind.
Of course, pay close attention to Harold's suggestions.
~RN
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