- Joined
- Aug 1, 2000
- Messages
- 863
This is the result of a discussion a few weeks ago in The Custom Knife Forum about flat grinding.....
The idea was originated by Ken Onion about a "rotary Platen" to eliminate the annoying thump and bump from tradition platen grinders. Inspired and encouraged by Ken and others, I built a prototype and tried it out today.
The basic idea is to use a secondary belt like a Tank track which rotates with the abrasive belt. By adjusting the tension on the secondary belt, you can effectively controll the membrane stiffness to appraoch a flat grind.
I started with an industry standard V-ribbed belt...type J, commonly found in machine tools and readily available from power transmission dealers.
With mini-"V" ribs on the back side, these belts ride on ribbed rollers and are locked in place side to side as the run. The abrasive belt tracks beautifully....and can be steered from side to side while the secondary belt remains in place.
I made the attachmnet with an optional center roller to add more support and to reduce deflection,....for flatter grinds.
The tension is precisely adjusted with a sliding bracket and jack screw.
I was amazed with the stiffness of the taught belt....with out the center roller.......and even more excited when I put the center roller on.
I just finished it today and I've only used it for about a 1/2 hr. I was most suprised by the whisper quite sound when I first turned it on. No belt rubbing across a platen. Then when I started grinding on it....it felt just like a contact wheel
.
Even though it has hardly been tested.....I couldn't contain my excitement and enthusiasm to share it.
I have another in process one with a different type of belt.
So, whatta ya think...? feasible, waste of time? any ideas for improvement. Would you like to see something different...?
I think it is remarkable! I am not the author of this wonderful idea.....I'm just a regular working smuck that built it. Credit for the idea goes to Ken Onion.
Thanks Ken!
Sincerely,
Rob
The idea was originated by Ken Onion about a "rotary Platen" to eliminate the annoying thump and bump from tradition platen grinders. Inspired and encouraged by Ken and others, I built a prototype and tried it out today.
The basic idea is to use a secondary belt like a Tank track which rotates with the abrasive belt. By adjusting the tension on the secondary belt, you can effectively controll the membrane stiffness to appraoch a flat grind.
I started with an industry standard V-ribbed belt...type J, commonly found in machine tools and readily available from power transmission dealers.
With mini-"V" ribs on the back side, these belts ride on ribbed rollers and are locked in place side to side as the run. The abrasive belt tracks beautifully....and can be steered from side to side while the secondary belt remains in place.
I made the attachmnet with an optional center roller to add more support and to reduce deflection,....for flatter grinds.
The tension is precisely adjusted with a sliding bracket and jack screw.
I was amazed with the stiffness of the taught belt....with out the center roller.......and even more excited when I put the center roller on.
I just finished it today and I've only used it for about a 1/2 hr. I was most suprised by the whisper quite sound when I first turned it on. No belt rubbing across a platen. Then when I started grinding on it....it felt just like a contact wheel
.
Even though it has hardly been tested.....I couldn't contain my excitement and enthusiasm to share it.
I have another in process one with a different type of belt.
So, whatta ya think...? feasible, waste of time? any ideas for improvement. Would you like to see something different...?
I think it is remarkable! I am not the author of this wonderful idea.....I'm just a regular working smuck that built it. Credit for the idea goes to Ken Onion.
Thanks Ken!
Sincerely,
Rob
nice job.
