I have just about got my Hercus 3 grinder up and running. I was planning a modification that I will post once I have this first issue sorted. I checked the pulley sizes and with the motor running at the advertised 1440 rpm I would have a spindle speed of 4300 rpm. This is above the Hercus stated 3500 rpm and is pushing the limits for some of the grinding wheels.

The present setup is 2 V belts and the belts are not running smooth due to age.

The belts are old and were going to be replaced but it looks like I will also need at least one new pulley.

On other tool grinders I have seen either flat or toothed belts.

I was leaning towards a flat belt but cannot find suitable pulleys. I must be using the wrong search words. Should I keep going down the flat belt path or will a toothed belt give as smooth running. I may as well get this right and go with the best solution. If flat belt I may end up making pulleys out of aluminum.

Thanks Steve


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