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a1gutterman
02-05-2007, 02:21 AM
Today, I visited the Home and Garden Show @ the Tacoma Dome in Tacoma WA. Mike was manning the Shopsmith display. On two occasions during his presentation, he referred to the SS as supplying 2 1/4 horsepower. I am wondering how that is figured since the SS has a 1 1/8 HP motor. Can anyone explain this to me?:confused:

dusty
02-05-2007, 06:25 AM
The manual that we all so frequently refer to for instructions on matters regarding our Shopsmith very clearly states that the Shopsmith motor is rated at 1 1/8hp but that may be just a bit conservative. Remember, Shopsmith has been around a long time and back in the beginning folks weren't inclined to exaggerate.

Facts man, just the facts.

My shop is wired to receive electrical power from the local power company. That power is sometimes referred to as 115 vac (volts alternating current). I have even heard it called 120 vac.

The manual says that we should expect our Shopsmith to draw as much as 14 amperes of current when heavily loaded like when ripping an oak plank in preparation for a furniture project.

A quick reference to the science text book tells me that 1 horsepower = 745.699872 watts.

Knowing that power (in watts) equals voltage (in volts) times current (in amperes) we can calculate the real power of our Shopsmith.

Therefore: 120vac x 15 amps = 1650 watts of power stated in horse power

1650 watts / 745.699872 watts = 2.21268 horsepower.

Now we all know that some of us use 20 ampere circuit breakers so maybe some of our machines develop even more horsepower than we think.

My final conclusion: Mike isn't wrong, he's a marketeer. In addition I have concluded that my 1 1/8 horsepower motor works just fine.

___________________
Making Sawdust Safely

james.miller
02-05-2007, 12:30 PM
Many tool manufacturers have stated their horsepower as the max that is reached just before the motor stalls and burns up under extreme load. Craftsman is known for doing that. The plate on the motor usually stated the horsepower that the motor can produce for an extended period of time without burning out.

Jim in Tucson

a1gutterman
02-06-2007, 10:29 PM
Thanks to both Dusty and Jim for your input. And Dusty, I did not doubt Mike; I just wanted an explanation:D .

Thanks again!

scottss
02-07-2007, 04:34 PM
How long are they going to be at Tacoma?

a1gutterman
02-07-2007, 08:09 PM
Hi Scottss,

I am sorry to tell you that they were only there for the weekend; however, they will be in Seattle soon:
We're Coming Your Way!
02/17/07 - 02/25/07Seattle, WAQwest Field Event Center (Previously Seahawks Exhibition Center)
Sat's: 10am-9pm, Sun's: 10am-6pm, Mon.: 10am-8:30pm, Tue. - Thur.: 11am-8:30pm,
Located at the junction of I-5 & I-90.
Hope this helps,:)