Thread: Polishing mop and compound

I want to use my bench grinder for polishing, primarily for the unicorn method of sharpening. Just looking for a good brand of mop and compound to buy. I can only get Josco stuff locally, and I heard that they are not of great quality. Any recommendations of what/where to buy?

I use Josco stuff and am quite happy with the results but I realize its not the best you can get.

Maybe take a look at Caswell's?
https://www.caswellplating.com.au/st...buffs-and-bobs

If you are just starting out maybe have a read of this
https://www.caswellplating.com.au/buffing.html

I received an order from Caswell 2 days ago and was very happy with it. On the old grinder I am using the Caswell tapered spindle worked better than a Josco. If Josco is easily accessible I guess you could try it and return it if doesn't run true.

Personally I used a roughly 4" stitched mop with green compound and got amazing initial results with the unicorn bevel on chisels.

I have read about others using larger wheels and white compound. I think that this would be more forgiving if one is making a unicorn edge on plane blades.

It depends why you are buffing but a 4" buffing wheel at normal grinder speed (2850 rpm) only has a linear surface speed of 2850 FPM.
This is below Caswell's recommended speed of between 3600 and 7500 FPM for efficient buffing.

I realize the work areas involved when sharpening are tiny compared to large workpieces so efficiency is not that big of a deal but an 8" wheel at 2850 rpm will give 5700 fpm which is much better.

The problem is compounded when buffing wheels wear and get smaller so if you start off with a bigger wheel it provides some leeway in the scheme of things.

The other thing is grinder power versus wheel diameter and thickness. To operate a thicker, larger diam mop requires more grinder power otherwise it will stall and overheat.

My grinders are 1HP 3phase on a variable speed drives so can run them up to 3600 rpm which means my 8" mops are running at 7200 fpm when new and 3600 FPM when down to 4" in diameter.

Thanks BobL, I have a 6" grinder

Originally Posted by Oldmeadow

Personally I used a roughly 4" stitched mop with green compound

Is the green compound from Caswell? Is it this stuff (that's stated for stainless steel)? https://www.caswellplating.com.au/st...teel-bar-large

Also, what's finer - green or white?

Along the same lines, does anyone know a source for a 1" 8 TPI threaded buffing spindle - I'm trying to get one for one of my 10" grinders but have drawn a blank with all the usual suppliers.

Originally Posted by yoboseyo

Thanks BobL, I have a 6" grinder
Is the green compound from Caswell? Is it this stuff (that's stated for stainless steel)? https://www.caswellplating.com.au/st...teel-bar-large

Also, what's finer - green or white?

Have a looks at the chart on this page.
https://www.puruipolishing.com/2020/...d-color-chart/

Originally Posted by Gavin Newman

Along the same lines, does anyone know a source for a 1" 8 TPI threaded buffing spindle - I'm trying to get one for one of my 10" grinders but have drawn a blank with all the usual suppliers.

I am also after these as well. Thanks Steve

I agree and got a bunch of 8" mops for that reason. They are mounted on a 1/2 HP or so grinder and I'm looking to upgrade to a much more powerful system, hopefully with variable speed (eg. treadmill motor with speed adjustment panel).

I haven't played around with unicorn bevelling on an 8" mop but plan to do so. My reasoning was that using a 4" mop to start with would be much more gentle while I get a sense of what works best. It appeared to work excellently right off the bat.

Originally Posted by BobL

It depends why you are buffing but a 4" buffing wheel at normal grinder speed (2850 rpm) only has a linear surface speed of 2850 FPM.
This is below Caswell's recommended speed of between 3600 and 7500 FPM for efficient buffing.

I realize the work areas involved when sharpening are tiny compared to large workpieces so efficiency is not that big of a deal but an 8" wheel at 2850 rpm will give 5700 rpm which is much better.