New member and already have machine problem

[ChazzC]

Sign up here so you can search for a Mentor in your area to see if they can come to you and help:

https://www.hobby-machinist.com/threads/mentors-mentees-read-this-first.95977/

 

[VicHobbyGuy]

I want the ability to carry it to a metal welding table but store it away when not using so weight and size are considerations. Looking at the Grizzly G0768 and it seems to fit those criteria.

You must be a pretty strong guy - that Grizzly weighs 160+ lbs according to the spec sheet, and when I've moved my 7x14, I found it an awkward carry. If you have the room, a rolling cart might save your back. You'll need some place to store all the lathe 'bits and pieces' anyway.

 

[VicHobbyGuy]

trying to figure it out. I don't know how to proceed...

Are you comfortable troubleshooting (checking voltages) with the power on?

 

[bikerdib]

If I buy the G768 it would be placed on a wheeled cart like all my other tools. My welders, wood planes, tablesaw, metal bandsaw, woodworking bandsaw, even my 18x36 wood lathe with extension kit; all my bigger equipment is on wheels. I'd just weld up a stand for the 768.

As to checking with power on, I have done so already. I found some instructions and I'm getting the 120 volts at terminals 6 and 7 and the board is putting out the 12 volts at terminals P1 and P3. It appears the issue is in either the direction change switch (and I have tried using both forward and reverse) or a little more likely the speed pentometer.

But even if I get this little guy going, I may still order a 768 for its extra capacity and power. I'll be doing mostly small steel projects and the extra power would be nice.

 

[VicHobbyGuy]

As to checking with power on, I have done so already. I found some instructions and I'm getting the 120 volts at terminals 6 and 7 and the board is putting out the 12 volts at terminals P1 and P3. It appears the issue is in either the direction change switch (and I have tried using both forward and reverse) or a little more likely the speed pentometer.

I'd try simplifying the wiring for troubleshooting, something like this:


If you test the potentiometer when it is out of circuit, do you get full resistance across the outside terminals and variable resistance at the middle (wiper) terminal? If necessary for testing you could replace the potentiometer with another one, or just a couple of resistors.
You could even bypass the power switch if necessary, though it sounds like that is OK.

You aren't getting DC at terminals 1&2?

 

[bikerdib]

VICHOBBYGUY said: "You aren't getting DC at terminals 1&2?"

The instructions I found said to check P1 and P3 for 12 volts, which I had.. After reading your message, I checked and yes I'm getting 12V at P1 and P2 and at P1 and P3 but 0 at P2 and P3.

I cannot check the pentometer out of circuit because those are all soldered connections.

 

[cooper1203]

try turning the pot and see if you get a voltage increase across p2 and p3 However that is a separate issue to the motor not turning if the above schematic is right if you have 12 volts on the motor output labeled 1 and 2 on the above schematic and you dont at the motor there is a broken connection. if you have 12v at the motor but the motor doesnt work the motor is fubared as far as that goes.

 

[bikerdib]

try turning the pot and see if you get a voltage increase across p2 and p3 However that is a separate issue to the motor not turning if the above schematic is right if you have 12 volts on the motor output labeled 1 and 2 on the above schematic and you dont at the motor there is a broken connection. if you have 12v at the motor but the motor doesnt work the motor is fubared as far as that goes.

Thanks but I pretty much eliminated the motor or controller to motor wires by using a 9 volt battery. The motor ran slow but smooth.

 

[bikerdib]

I found some instructions from Little Machine Shop and while they are for a different model of HF, I think the apply here too.

The PDF instructions are here: https://www.google.com/url?sa=t&sou...gQFnoECB4QAQ&usg=AOvVaw2zR5h9vGjJx2OVjDHsAl5Z

I got the correct results using the outlined method testing the pentometer. However, when testing the direction switch, in off position there was zero continuity at any connection. But placing the switch in either forward or reverse, I get continuity at ALL connections. I think maybe the switch is shorted?

 

[cooper1203]

Thanks but I pretty much eliminated the motor or controller to motor wires by using a 9 volt battery. The motor ran slow but smooth.

and you have voltage at the other end of the wire on the board output? if there is nothing else between that and the motor the wire must be broken