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Bluedog
05-21-2011, 06:43 PM
I have a Grizzly G4003 lathe that I started having issues with today. Now when I press the power start button, the lathe automatically starts in the forward direction with the spindle control in neutral. If the spindle control is in gear (forward or reverse), the power start button operates normally and will not engage. Kind of scared me when it first happened, the lathe just started on it's own when I pressed the power start button. I can hear the spindle control switch click when I move the lever from forward to neutral to reverse. No way to make it run in reverse. Anyone have this problem before?

Thanks!

The Artful Bodger
05-21-2011, 06:53 PM
Impossible to tell from a distance but I would first suspect the mechanism where the spindle control lever operates micro switches. I suggest checking where the control rod actuates the switches and ensure everything is clean in that area.

MetalMunger
05-21-2011, 07:22 PM
You have a stuck contact on:
1) Contactor KM-1 and/or KM-2
2) The spindle control switch. +1 Artful

Bluedog
05-21-2011, 10:30 PM
Thanks for the replies. The electrical components section of the manual refers to two magnetic contactors (052 & 053), is this the KM-1 and KM-2 you are referring to? Any tips to check them, or unstick them?

http://cdn0.grizzly.com/manuals/g4003_m.pdf
Page 32 & 33

Thanks Again.

The Artful Bodger
05-21-2011, 10:45 PM
I am not familiar with the exact type of contactor but if they are at fault they might be stuck and the only satisfactory repair for that is replacement. However the may be 'stuck' and not be faulty which is how they might appear if they are being held shut through a fault elsewhere, such a fault might be stuck micro switches on the handle or a short in the wiring.

I suggest take off the electrical cover with all switches off including the wall switch. Ensure the red stop button is also 'off' then switch on the wall switch listening for any noises from the electrical box, there should not be any.

John

MetalMunger
05-21-2011, 10:57 PM
Thanks for the replies. The electrical components section of the manual refers to two magnetic contactors (052 & 053), is this the KM-1 and KM-2 you are referring to? Any tips to check them, or unstick them?

http://cdn0.grizzly.com/manuals/g4003_m.pdf
Page 32 & 33

Thanks Again.

(052 & 053) are them!
By the nature of your reply I will infer that your knowledge of thing that spark and arc minimal at best.
So the following troubleshooting procedure:
1) Buy a six-pack of good beer.
2) Find a buddy that understands things that spark and arc.
3) Offer the buddy good beer for his time and bringing his volt-ohmmeter to your house.

OR

1) Go to http://utwired.engr.utexas.edu/rgd1/lesson01.cfm
take the lesson #1 on Ohm's law.
and
http://www.autoshop101.com/forms/elec11.pdf
2) Go to Lowes's buy a $25 volt-ohmmeter.
3) Disconnect your lathe from any electrical source or supply!!!
3) Apply what you have learned.

Getting the beer and the buddy is quicker easier and more fun imho :D

Bluedog
05-22-2011, 12:20 AM
Actually, I have a fair knowledge of "things that spark & arc" (LOL), and I've even got a multimeter. Father was an electrician, I had a few electrical engineering classes in college, heck I even CNCd my mini mill. I'm just very new to a lathe. I just bought it used a couple of months ago, and I'm learning to use it by trial and error; going better than I expected too.

When facing the contactors, when you press the power start button the far right contactor (053) engages and the far left (052) engages. By manually pressing the contact, I found that the one on the far left is forward and the one in the middle is reverse. I'm assuming that only 053 should engage when the power start button is pressed, then one of the 052's when you shift the lever to forward or reverse. Correct? If you shift the spindle control lever to forward or reverse and then press the pwr start button nothing happens as expected. That leads me to believe the left 052 (forward) contact is defective and not the spindle control switch, or am I looking at this wrong? I'm having too much fun to be down for too long, so should I just order the spindle control switch also?

Thanks for the help.

Lu47Dan
05-22-2011, 12:30 AM
Bluedog, before you order parts see if you can find a local dealer in those type of parts. If you have a local dealer you can save some money even if the part is a little higher then the OEM's part is, No shipping and handling charges, sometimes no wait and you can go back and get any other part you need.
Do the contacts in the contactor come out? sometimes they do, inspect them and if they are not welded together, clean them with a little contact cleaner and air then install them and test to see if it works. I had the contactor on my Clausing hang up and it would not shut down, I had to swing the lathe away from the wall and clean them in the box with an air wipe. It cured the problem as a lot of crap got blown out of the control box.
Dan.

mechanicalmagic
05-22-2011, 12:39 AM
I'm assuming that only 053 should engage when the power start button is pressed, then one of the 052's when you shift the lever to forward or reverse. Correct?
That's what I remember. (My G4003 is now VFD'd).

If you shift the spindle control lever to forward or reverse and then press the pwr start button nothing happens as expected.
That's good.

That leads me to believe the left 052 (forward) contact is defective and not the spindle control switch, or am I looking at this wrong?
If the 052 engages when the shift lever is in neutral, the spindle control switch is probably faulty.

I think.
DJ

Boostinjdm
05-22-2011, 01:28 AM
If by shift lever you mean the forward, off, reverse lever on the carriage. Then check to see that it is centering correctly. I believe it is locked in place with a set screw. I've had that screw come loose on a grizzly before.

MetalMunger
05-22-2011, 02:13 AM
Actually, I have a fair knowledge of "things that spark & arc" (LOL), and I've even got a multimeter.
Thanks for the help.
OK Sparky!
1) Go back to the "Grizzly" site and download the manual for the G4003G
http://cdn0.grizzly.com/manuals/g4003g_m.pdf
More better color pictures too, maybe the wiring ain't the same but you should be able to figure things out.
2) Disconnect all power!
2) Remove the cover from the "Spindle Selector Switch" check to make sure the contacts are moving correctly.
3) With no Power the armatures on both contactors should be fully retracted (towards you). If one contactor appears to be forward try moving the armature by pressing in with a screwdriver and releasing.
if both items 2&3 appear to be normal grab your trusty VOM and start checking all switch and contactor contacts to verify normaly open/ closed position lift wires one at a time if required. Remember NO NC is in a de-energized sitting on the shelf condition.

Bluedog
05-26-2011, 11:57 PM
I have determined I need the spindle forward/reverse switch. Part #P4002919A for the G4003 & G4002 or Part #P4003G0919 for the G4003G will work. Bad news is Grizzly has them on backorder until Mid July and that is not confirmed, so really no idea when they will get them. Anyone have a source for such a switch? I know many of the chinese machines are the same, just painted a different color for different companies. Any other supplier sell the same lathe (& parts) under a different brand?

Thanks

mechanicalmagic
05-27-2011, 12:45 AM
I could be WAYYY off base here. I VFD'd my 4003 many years ago, and was into all the switches. I would swear that little box just had standard micro-switches in it. (And cam actuators.)
I would not hesitate to pull it off and take a good look.
DJ

MetalMunger
05-27-2011, 02:25 AM
PM sent.:)