Mark V--blowing fuses and refusing to tu

[Jbmullaney]

Hello all,
I inherited a Mark V from a family friend, and I have greatly enjoyed it, primarily for wood turning, when it is is working condition--unfortunately, there have been some issues. I have had no issues with turning bowls with my current electrical set up in my shop. My major issue right now is this:

-With a wood blank on the machine, it will turn up to speed (it will speed up and slow down just fine), but as soon as I touch a tool to the wood, there is no resistance and it stops turning.
-Around this time the circuit breaker usually trips too.
-And get a little "electrical incense" smell.

I have already replaced the speed controller and the control sheave assembly previous to these most recent problems. The speed control broke loose at some point and burnt up--probably because the clip in the sheave control assembly fused. All is in working order now.

Any help you can offer would be appreciated! I've got Christmas presents to make.

Thanks,
John

[dusty]

Hello all,
I inherited a Mark V from a family friend, and I have greatly enjoyed it, primarily for wood turning, when it is is working condition--unfortunately, there have been some issues. I have had no issues with turning bowls with my current electrical set up in my shop. My major issue right now is this:

-With a wood blank on the machine, it will turn up to speed (it will speed up and slow down just fine), but as soon as I touch a tool to the wood, there is no resistance and it stops turning.
-Around this time the circuit breaker usually trips too.
-And get a little "electrical incense" smell.

I have already replaced the speed controller and the control sheave assembly previous to these most recent problems. The speed control broke loose at some point and burnt up--probably because the clip in the sheave control assembly fused. All is in working order now.

Any help you can offer would be appreciated! I've got Christmas presents to make.

Thanks,
John

I would start by making sure that belt tension is set properly and then move on to verifying the condition of the power cord, plug and switch. You have an unusual combination of symptoms.

[Jbmullaney]

I've never checked belt tension before. How do you do that? (I'm learning as I go with this piece of equipment!)

[rpd]

I've never checked belt tension before. How do you do that? (I'm learning as I go with this piece of equipment!)

Here is a video that shows how to adjust the belt tension.
[youtube]https://www.youtube.com/watch?v=J2RSrFpr5Sk[/youtube]

[JPG]

A mantra of diagnosing: Never 'assume' anything especially past history.

But do consider recent history.

At this point I would do a visual inspection of all wiring.

When you say previous speed control 'burnt up', you are referring to mechanical parts?

When you say "it will speed up and slow down just fine", are you referring to the result of adjusting the speed control, or how it acts as it starts up?

Last, what motor do you have(3/4 or 1 1/8 HP)?
Oh, and how big is the blank today.




P.S. If you replaced the control sheave, did you not adjust drive belt tension then? Gilmer or Poly-V?

[Jbmullaney]

JPG,
-Yes speed control assembly (where it clips to the sheave)somehow was not centered and the the sheave and speed control rubbed against one another and warped the speed control assembly. Since replacement, all parts are aligned and run smoothly.

-Adjusting speed control was what I was referring to.

-Not sure which motor I have. Is there an easy way to check?

-The blank was 6"x6"x3"--never had any problem with this size blank--probably turned a dozen bowls this size.

-When I replaced the sheave I did not adjust the belt tension. Again, I'm
learning as I go--I'm sure I'm missing things I should be doing.

Thanks for your help!

[JPG]

There is a shiney plate on the left end of the headstock surrounding the idler shaft. If old enough it will have a serial number. In any event it should reveal the motor size. If the original paint is not green or gold(brown) it is 1 1/8 hp with a Poly-v drive belt.

A loose belt will explain the workpiece 'stopping', but not the power interrupter nor the 'incense'.

[wa2crk]

Hint from the "OK I'm dead thread"
Are you plugged into a wall outlet or a multiple outlet power strip?
Are you tripping the power strip breaker or the breaker in the house power panel?
Power strips are notorious for having touchy breakers.
Just some food for thought.
Bill V

[tdorey]

Have you checked trueness? Blade is perfectly square to fence. I found if it's not perfect, wood will bind and would blow my breaker.

As a new user I find getting and keeping everything strait and true is tricky and requires attention.

[JPG]

He is trying to spin a bowl blank!