Power surging

[hnderson]

I was informed on this forum that I needed a dedicated 12 ga 20 amp circuit to make sure my shopsmith has enough power. I just finished putting the circuit in but find my surging problem is not solved.

Here's the history: I have an old shopsmith V. I bought it not working and sent it to someone who rebuilds them. A rebuilt motor was installed. It's a 1 1/8 HP AO Smith motor. I used it intermittently for a few years as a bandsaw only. I tried using the table saw a couple of times but it didn't have enough power. As I didn't really need the table saw, I just used the bandsaw that worked fine.

In '09, we moved to Oregon. I have an unheated workshop. We started using the table saw for helping us do some remodelling. It worked fine over the summer. However, as soon as the rainy season started, I started losing power. Temperatures have been in the 30 to 50+ during the day. But I think when the rains first started, the temps were higher - probably in the 60s plus.

When I turn the power on, it takes 10 seconds to get up to speed. At full speed, the power surges constantly. Any cutting bogs it down to a stop. I find it strange that it worked fine one day but the next time I try it, it doesn't.

As the power in the shop was on 14ga wire, I added the dedicated 12ga circuit last week. When I saw that didn't make any difference, I checked belts which seemed fine. I pulled the motor. The shaft spins freely. I plan to take it in to have it gone over.

I'm wondering if I could be missing something simple to check. And I'm wondering if the cord on the motor is adequate. I'm not sure what size the wires are. It's braided but looks smaller than a 12 ga.

Humidity and temperature are the only things I can think of that are different from when the SS was working fine. Am I missing anything? And could those two things cause my problem? If so, is there anything that can be done about them (other than heating my shop)?

Harold

[dusty]

I was informed on this forum that I needed a dedicated 12 ga 20 amp circuit to make sure my shopsmith has enough power. I just finished putting the circuit in but find my surging problem is not solved.

........................

When I turn the power on, it takes 10 seconds to get up to speed. At full speed, the power surges constantly. Any cutting bogs it down to a stop. I find it strange that it worked fine one day but the next time I try it, it doesn't.

.........................


Harold

Concentrating on only two statements you have made

Please expand on what you mean by "surging". Are you saying that the motor does not run at a constant speed even though you are not using it.

And

Does it literally take 10 seconds to come to speed. It does not happen instantly but 10 seconds seems a bit long under no load (with the motor belt removed).

Do you lubricant the headstock regularly and what do you use for oiling?

Ambient Temperatures and humidity are a couple of the last conditions that I would suspect as cause for your symptoms.

Proper cleaning and lubrication and properly tensioned belts and belt condition are more suspect.

[beeg]

What temp is your shop? Is the receptacle ya put in a 20 ampere? Have ya lube it lately?

[JPG]

What temp is your shop? Is the receptacle ya put in a 20 amper? Have ya lube it lately?

If you have lubed it, with what? SAE 10 is the correct thing. If you used motor oil of higher viscosity, that would contribute to slow startup.

The linecord is probably not #12. It is short, so not likely to add to this problem. The use of a 20A receptacle will only gain you the capability of plugging in a 20A device(with a special 20A plug).

I believe a clue is the previous inability to run anything other than the bandsaw. How was the motor 'rebuilt'. Is it a proper motor(120V 60Hz 1 Phase 3450 RPM). It almost sounds as if it is a 230V motor and you are attempting to run it on 115V. Finally, is the proper size start capacitor installed and is the start circuit(switch and capacitor) operating correctly?

Last but not least, does everything turn freely by hand?

Depending upon the answers to these questions(including the previous posts) you may need to isolate the problem by removing belts etc.

[a1gutterman]

...When I turn the power on, it takes 10 seconds to get up to speed. At full speed, the power surges constantly. Any cutting bogs it down to a stop. I find it strange that it worked fine one day but the next time I try it, it doesn't...I'm wondering if I could be missing something simple to check...

Hi Harold,

This might be a reach, but I lived in a house that had overhead power to it. The power lines went through some tree branches and over the years, the branches came in to contact with the lines. The movement of the branches eventually wore through the power line insulation and created an intermittent ground. The effect of that was surging in my house. I had no idea what was causing it, but when it ruined my television, I called the power company and they discovered what the problem was and corrected it.

Is your Mark V the only thing in your home that surges? Do your lights flicker? Like I said, it might be reaching, but check it out. You may have a similar problem to the one I had.

[JPG]

Hi Harold,

This might be a reach, but I lived in a house that had overhead power to it. The power lines went through some tree branches and over the years, the branches came in to contact with the lines. The movement of the branches eventually wore through the power line insulation and created an intermittent ground. The effect of that was surging in my house. I had no idea what was causing it, but when it ruined my television, I called the power company and they discovered what the problem was and corrected it.

Is your Mark V the only thing in your home that surges? Do your lights flicker? Like I said, it might be reaching, but check it out. You may have a similar problem to the one I had.

That problem can lead to many funky problems. The bottom line is the voltage can become in excess(and low also) of what some devices can withstand. As different devices are turned on and off, the voltage to all other devices may change.

TIM: Did they replace the tv? They should have! I assume the drop was what got 'worn'.

[a1gutterman]

...TIM: Did they replace the tv? They should have! I assume the drop was what got 'worn'.

At the time I was young and dumb and...well, I did knot ask and they did knot offer. I later figured that I should have, but it was too late for that.

[hnderson]

Thanks for all the replies. As to the power surging, once running, the motor slows, then speeds back up. The change from high to low is over about 2 seconds. The belts were in place.

I am guilty of not having oiled regularly. I doubt that's it, though. When I removed the belts, the motor shaft rotates freely. When I run anything (1/4" pine strip) into the blade, it bogs down for a few seconds, then the breaker trips. I haven't run anything through the blade since putting in the dedicated line but the motor's acting the same as it had on the shared circuit.

I don't notice the lights flickering and my skill saw works fine.

I don't know how the motor was rebuilt. It came from someone who only works on Shopsmith. I ran into him on a different Shopsmith forum - I think in 2003.

The motor is marked 115V single phase 60 hz 3450 RPM.

I appreciate the help.

[nomoman]

I don't know how the motor was rebuilt. It came from someone who only works on Shopsmith. I ran into him on a different Shopsmith forum - I think in 2003.The motor is marked 115V single phase 60 hz 3450 RPM. I appreciate the help.

If you contact jacobvb1 (Jacob Anderson). He might be able to help you with the motor. I am not sure where you are located, but he is in Virginia Beach.

[dusty]

Harold,

I still believe it is important to know what the motor does when run with the drive belt removed. Does it still surge or does it come up to speed and run at a constant speed.

Are the belts, especially the drive belt (motor belt) in good condition?

I don't believe the primary power is causing issues! If it was the primary motor, you would have other symptoms throughout the house. However, you might confirm this by running your Mark V off of a different circuit ( plug in where the skil saw seems to work).