My surface grinder takes 7" wheels with a 1-1/4" ID. All of my adapters had slots on the back for balance weights but none had the weights installed, nor did the grinder come with any. So I made some new weights from 303 SS and was then able to balance my wheels. To be fair, I found that only one of the CGW wheels I bought needed a lot of work. Turns out the remaining 5 wheels were OK. So, CGW wheels are IMHO, decent wheels for the money. They're not Norton quality, but they're not that bad either.
Here's how I made the weights. A typical balancing weight is a small arc shaped gizmo with a small tapered set screw and a ball bearing protruding from the side. The tapered set screw pushes the ball bearing out the side of the weight and holds the weight in the groove. So, I made a ring from 303 SS, tapped it in 8 places for a 10-32 setscrew using the rotary table. Then, using a slitting saw, I separated the ring into 8 segments. On each of the eight segments, I drilled a hole from the ID into the tapped hole. Then all I needed to do was grind a taper on eight setscrews, insert a ball bearing into each hole and install them into the surface grinder wheel adapters. Two weights per adapter.
Balancing is a snap. Leave the weights off for now. First, install the new wheel onto the grinder and by eye position the wheel on the adapter to minimize runout (there is a small amount of slop between the ID of the wheel and the OD of the adpater. Now dress the wheel even the sides if it looks like the wheel is wobbling (none of the Norton wheels I have wobble - but a few of the imports did).
Remove the wheel from the grinder. Do not take the wheel off the adapter. Install the balancing arbor (I made my own) into the wheel adapter and put it on a balancing stand. I borrowed one, but if your lathe is level you can put two parallels on the ways and use that as a balacning stand. Now, let the wheel settle to where its heavy spot is on the bottom. Now, install the two weights at the 9 and 3 o'clock positions. The wheel should still settle to the same spot. It's a simple matter to achieve balance by moving the two weights closer together a little bit at a time (towards the light side) until balance is achieved.
Now take the balanced wheel and adapter and install it on to the surface grinder. Dress the wheel once more and you're good to go. A good balance makes a world of difference in the surface finish!
I have three adapters that have no provision for weights. I used two of these on wheels that were balanced out of the box (both are Norton wheels). The remaining adapter was used on a diamond wheel.
At some point, I'll make a balancing adapter to retrofit these wheel adpaters to allow them to be balanced. One thought is to make a separate hub that clamps over the back of the wheel adapter with a slot for the balancing weights. Another option would be a thingy that takes the place of the washer in between the adpater and the wheel. In any case, since everything I have is now balanced, this is low on the project priority list.
John
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