Replies

1. 
   ring | Aug 06, 2009 07:26am | #1

   What exactly is the problem? If the arbor size is too small for the wheel's bore, you can use bushings to adapt. If you could be specific about why it doesn't fit, maybe someone could be specific about a solution.

   David Ring

   http://www.touchwood.co.il/?lang=e&id=1

   
   

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   Edited 8/6/2009 12:27 am by ring

1. 
   jeffs | Aug 06, 2009 07:36am | #2

   Thanks for the response. My question is more general. My machine is called a 6" grinder but I don't understand why I can't put an 8" wheel on it.  

    

1. 
   davcefai | Aug 06, 2009 08:34am | #4

   An 8" wheel needs more power. 1 rev is using ~ 24" of grinding surface whereas a 6" one uses ~18". Consequently, for the same pressure of the tool against the wheel, the 8" is doing 50% more work.Having said that, my 5" grinder has the same motor as the 6" version and is working quite happily with 6" wheels.However, as FG pointed out, there is the safety aspect.

2. 
   ring | Aug 06, 2009 09:06am | #5

   You can put an 8" wheel on it, but under some circumstances it might be underpowered. And there's the question of the guard... The Knots safety patrol would have arrested me long ago for things I've done to grinders, but I'm far away and they don't see. If you're comfortable with it, just do it.
   David Ring

   http://www.touchwood.co.il/?lang=e&id=1

2. 
   forestgirl | Aug 06, 2009 07:47am | #3

   I would think the wheel covers would be a bit hard to stretch?

   forestgirl -- you can take the girl out of the forest, but you can't take the forest out of the girl ;-) 
   
3. 
   Buster2000 | Aug 06, 2009 09:10am | #6

   Looking at a few sites shows that the 8" grinders typically have a 5amp motor, while 6" only have a 2.5 amp. he 8" wheels just take more power to turn.

   I'd also watch maximum RPM's. The maximum RPM for an 8" wheel is typically less than a 6" wheel. Lee Valley as the max RPM's for the Norton 3X wheels at 5410 for the 6" and only 3600 for the 8". That said, it appears that most 6" and 8" grinding wheels operate at about 3450RPM on the high end...

   I'd really think about the safety aspect. You'd have to remove the guards. For the cost of an 8" grinder it's not worth the risk.

4. 
   JohnWW | Aug 06, 2009 12:42pm | #7

   Jeff,

   How slow is "slow speed"? Also is there an enclosure around the wheel and is this a more or less conventional type of machine with two vertical wheels?

   John White
   Shop Manager for FWW Magazine, 1998-2007

1. 
   jeffs | Aug 06, 2009 05:06pm | #8

   JWW

   this is a 1800 rpm, 3 amp typical grinder with two vertical wheels. I would have to remove the std wheel covering and replace them with some other way to cover them for safety.

   Perhaps being 3 amp it would be under powered as others have said

   Jeff

1. 
   JohnWW | Aug 12, 2009 09:12pm | #10

   Jeff,It would be far easier, and much safer, to buy the appropriate size grinder for the wheel size you want than to try to jury rig a new guard for the machine you have. An exploding grinding wheel can cause huge amounts of damage to your face and chest, this is one place where you can't compromise. 3 amps is more than adequate for a 6" grinder with 3/4" wide wheels especially for the light grinding involved in tool sharpening.John White
   Shop Manager for FWW Magazine, 1998-2007

1. 
   jeffs | Aug 12, 2009 11:54pm | #11

   thanks for the feedback- I have already bought 6" Norton wheels for my existing grinder- at this point I didn't think there was enough advantage to buying a new grinder to get 8" wheels.

    

5. 
   oldusty | Aug 07, 2009 05:09pm | #9

      Jeff ,

              If you have 8" wheels already that wont quite fit you could always have them dressed   down to size maybe 7" will fit fine , yup you will need another grinder or perhaps you can figure a way.And of course a stone dresser.

        I use an 8" and a 6" but if anything it is easier to use smaller wheels not larger then the capacity .

      regards      dusty