Eccentric tool grinding jig.

Ken226

Ken226

Registered
Registered
Joined
Jan 6, 2017
Messages
1,214
I had an idea for a HSS lathe tool grinding jig.

It uses a rotatable tool holding turret, mounted on an eccentric, which itself rotates independent of the turret and base.

The middle eccentric part is machined with it's 2 faces at a 12° angle to each other, and can be rotated 360°.

The combination of eccentric positions, turret positions, and putting the blank into the slot with whichever of it's 4 faces to be ground facing the belt/wheel should allow grinding nearly any angle desired, and relief/rake angles from 0°, up to 12°.

The larger center screw secures the eccentric to the base, and the two smaller screws secure the tool holding turret to the eccentric.

I wonder if this thing would be worth the effort of making.





 
Interesting concept. Nothing like physical prototyping. You've gone this far, I'd say take a swing at making one and see how it works.
 
That’s awesome. It needs to be made.

The toughest feature to machine would be the vernier scale. 4 flats milled on the bottom piece plus a reference flat would let you use an angle gage. For the top piece relief angles you could use a cheapo digital level. Tool bits don’t need that much precision.

Machining the angle on the eccentric looks tricky. Machine the angle onto a fixture with a rotary table on the mill, and machine the part in lathe for a better finish and TIR?


Sent from my iPhone using Tapatalk
 
Watchwatch said:
That’s awesome. It needs to be made.

The toughest feature to machine would be the vernier scale. 4 flats milled on the bottom piece plus a reference flat would let you use an angle gage. For the top piece relief angles you could use a cheapo digital level. Tool bits don’t need that much precision.

Machining the angle on the eccentric looks tricky. Machine the angle onto a fixture with a rotary table on the mill, and machine the part in lathe for a better finish and TIR?


Sent from my iPhone using Tapatalk
Click to expand...


I had intended to use a CNC mill for the base piece vernier scale, and a CNC with rotary table for the vernier scales on the other two parts.

For the eccentric, the plan was to start with square stock, mill the angle first in a vice with angle blocks under it. Then use a CNC profile op to make the circular shape,

Then as you said, make an angled fixture and turn the angled cylindrical feature on the lathe. Then back to the CNC for the vernier scale

Looks like I'll get to use all 3 machines for this project. The CNC mill, manuAl mill and lathe.
 
Last edited:
Cool idea, Ken. Bet it would work well.

Then again, a good adjustable tool rest and an inked line would work, too.
 
You must log in or register to reply here.
Back
Top