Shopsmith Forums

judaspre1982 wrote:I will make note of the motor position on my Power Station and document it here. I know it has never been adjusted because when I asked the seller If he minded if I check the belts and sheaves, he said
"What belts and sheaves ".
There may have been some design or construction changes between model years, so the info I provide can at least be used as a starting point for motor position.
Now back out to shovel/blow some snow:( .------Dave

I don't know for sure why, but I drug myself out to the shop to dismantle and play with the Power Station again. I guess I am bothered by the fact that I can not get the belts to look as though they are properly tensioned and I attribute the noise of the Power Station to belt vibration.

I have not done anything that changes that but I am now certain that I understand the variator. I also have some dimensions that should help, I hope.

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The pulley speeds, depicted to the right of each respective pulley, are 'calculated speeds' based on pulley size and separation. Note that the speeds do not exactly match the advertised high and low speeds from the charts in the manuals. Note that the bottom pulley is the motor pulley and that speed is not calculated it is actual speed.

The calculated belt dimensions (shown to the left of each respective belt) are all reasonably close to 25" (the measured length of the specified belt). I was unable to locate a spec sheet for these belts or the pulleys involved. These seem to be protected like national security items. I can find more information about the US nuclear defense systems than I can about Shopsmith bits and pieces.

Lowering the motor a little might balance these numbers but I am not about to do that just to make it numbers look right. It is working (though noisy) so I'll not fix it.

For anyone needing a math refresher in applied ratios, this would be a good project to tackle. No fair using the computer.

Tools used: http://www.owwm.com/math/beltlength.aspx and http://www.owwm.com/math/arborrpm.aspx

CORRECTIONS: The large red pulley is NOT 5 1/4" in diameter as shown in the drawings. The variator is 5" (5.067" to be exact). It is mounted on a shaft that I thought was 5/8" but it is not. The variator shaft is .564" (9/16").

Changing that pulley size will alter the calculated speeds and belt dimensions but I'll leave those corrections to those with an interest in that level of detail.

dusty wrote: For anyone needing a math refresher in applied ratios, this would be a good project to tackle. No fair using the computer.

All is fair in love, war and solving math problems.