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Need info on the Graves Preformer

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Author Topic: Need info on the Graves Preformer  (Read 353 times)
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« on: April 06, 2016, 05:41:38 pm »

I just received my Graves Preformer in todays mail.  After inspecting it, I am slightly disappointed in the motor assembly.  I purchased the motor since it was almost half the list price and if I would buy it later the shipping was almost $20.00.  I assembled the preformer and attached the motor.  After turning on the motor I found the motor shaft unscrews off of the dop shaft, an easy fix with a setscrew but I would have thought this should have been corrected way before this. Also the on/off switch is flaky, not a crisp switching. The spring clip used to hold the cam against the stop is too small to easily attach to the motor pin.  Also, if using the motor, you have to completely disassemble the unit to change cams.

The performer itself seems well made although it does not easily lend itself to being mounted on the left side of a verticle wheel.  The cam engagement is set up for operating on the right side and if you mount it on the left side you will not be able to adjust the pressure down into the wheel during the grinding process.

My recommendation, if you plan to purchase the performer, don't invest in the motor unit unless you plan to make the same shape cab in quantity.  If you plan to change the cams for different shape cabs, you are better off using the manual version.

Since the assembly is mounted on the right side of the wheel and your wheels rotate top down they use a motor with a clockwise rotation. The idea is to have the motor rotation running against the cutting wheel rotation. If the rotation is going WITH the wheel rotation then your cutting will be drastically slower.

The problem of course is when the threading on the shaft adapter is incorrect and allows the spindle to unscrew.
To fix this I use a set screw (like you mentioned) to prevent it from unscrewing.
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