# Holme Made Tool and Cutter Grinder -  Courtesy Harold Hall



## Maryak (Mar 1, 2010)

Hi Guys,

I was lucky enough to find a copy of Harold Hall's Book on Milling in our local library. The last chapter shows how he adapted his grinding rest into a simple Tool and Cutter Grinder. There must be considerable interest in our hobby in this council area as this is the second book in the Workshop Practice Series I have found in 2 of the library's branches.

Having made Harold's Grinding Rest some 3 years ago and fitted it to my existing bench grinder, I was never completely happy as I was trying to do too much with one machine and everything became too much trouble, (sharpening drills, sharpening end mills, grinding lathe tools and offhand on the other wheel).

Don't quite know why the Gods smiled on me but I found a 125mm Bench Grinder for $AU25. 







The cut out from our kitchen sink - I knew it was good for something...........just not sure what. :






Cut it up and finished with a base for the Grinder.






This plus a visit to a house being built nearby provided the materials for mounting the bench grinder and matching the centre height to the Grinding Rest.













A few mods to the grinder, fit a cup wheel and a dish wheel and I should be good to go when the paint has dried.

Best Regards
bob


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## Mo deller (Mar 1, 2010)

I like it Thm: Something I need to sort out as well.

Peter.


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## ariz (Mar 4, 2010)

me too! I would like to see how you install the cup wheel on the bench grinder...

thanks for sharing


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## Maryak (Apr 8, 2010)

Hi Guys,

Finally found an appropriate straight cup grinding wheel. Amongst my grinding odds and ends was an arbor from an old 6" saucer wheel which turned out to be a perfect fit in the cup wheel so it was a simple matter to fit the wheel.






Now all I have to do is make a wheel guard but I wanted to do work on my engine so this will have to wait.

Best Regards
Bob


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## ariz (Apr 8, 2010)

great Bob! this is the solution I would like to reach for my grinder, because a cup wheel would last much more than a normal wheel

but I'm not sure to be able to build a wheel guard, so I'll wait to see how you do build yours ;D

thanks for sharing it


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## steamer (Apr 8, 2010)

Oh this has been a pet of mine for some time.....I need some way to sharpen my endmills.......paitiently watching..... ;D

Dave


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## ozzie34231 (Apr 13, 2012)

I know this topic has been quiet, but I thought I'd pop in with an idea I've used regarding grinding wheel guards.
Decide what diameter you want, then go to goodwill or Target, etc. find a cheap pot the needed diameter and depth and there you have a starting point. Cut away the unneeded parts, maybe make an adapter, ..............

Ozzie


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## AR1911 (Apr 13, 2012)

So why is it cup wheels are preferred?

I have some white stone wheels, not cupped.
Does the white color signify a particular grade?


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## Maryak (Apr 13, 2012)

AR1911  said:
			
		

> So why is it cup wheels are preferred?
> 
> I have some white stone wheels, not cupped.
> Does the white color signify a particular grade?



Cup wheels are designed to grind on what is the side of the wheel for a "normal" grinding wheel. This gives a flat facet rather than one which is slightly concave. Grinding on the side of a "normal" wheel is loading the bond matrix in a way which can weaken the wheels integrity. If you have had the misfortune to be around when a grinding wheel shatters, believe me, you would not want a repeat performance.

White wheels are aluminium oxide which are suitable for harder steels, like HSS and high carbon steels as opposed to the more prevalent gray aluminium oxide wheels which are for general purpose steels.

Hope this helps

Best Regards
Bob


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## petertha (Apr 13, 2012)

Is the idea of the collet holder you made that it can rotate its captured workpiece while grinding? Or maybe set at a specific rotated angle prior to grinding? Or maybe both? I was wondering why typical commercial collet blocks were not integrated, but maybe thats why.


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## Maryak (Apr 13, 2012)

ozzie34231  said:
			
		

> I know this topic has been quiet, but I thought I'd pop in with an idea I've used regarding grinding wheel guards.
> Decide what diameter you want, then go to goodwill or Target, etc. find a cheap pot the needed diameter and depth and there you have a starting point. Cut away the unneeded parts, maybe make an adapter, ..............
> 
> Ozzie



Ozzie,

Thanks for the idea. :bow: I'm off to Target next pension day ;D



			
				petertha  said:
			
		

> Is the idea of the collet holder you made that it can rotate its captured workpiece while grinding? Or maybe set at a specific rotated angle prior to grinding? Or maybe both? I was wondering why typical commercial collet blocks were not integrated, but maybe thats why.



Hi Peter,

Yes, the collet holder has 2 index collars for the back, one with 4 divisions and one with six. These are used to index various cutters for sharpening the ends. In this mode the collet holder is locked in each position whilst grinding.

Removing these collars from the back and fitting a flute stop at the front allows the collet holder to not only rotate but move axially to enable sharpening of the flutes of an end mill or slot drill.

I have not tried this, perhaps when I have a duff end mill I will see what happens. My initial thoughts are that the whole thing is not stable enough for this to be complete success.

Best Regards
Bob


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