Upgrading from G4000 to G4003G, Shop Visit?

[gregrycm]

I am contemplating upgrading my lathe from a Grizzly G4000 to G4003G.

I have motor vibration issues on the G4000, which I could likely fix by replacing with new AC motor, or migrating to 3-PH Motor with VFD controller, etc. But rather than putting more money into the G4000, I am considering it a good starter lathe, and am ready to upgrade.

I still need to review all of the comments on this board before pulling the trigger, but I was wondering if anyone had the G4003G lathe with-in a couple hour radius of Springfield IL?

If you have used the G4003G lathe, or similar, what did you think?

Thanks,
Greg

[RSG]

I just bought the same lathe only it's branded as King Equipment up here in Canada. So far I like the fit and finish and the spec sheet for allowable run out and so on is better than allowable spec. Since I haven't made any chips with it yet I can't give you any report worth reviewing other than to say so far so good!

[ortho]

How about within 30 hours radius of Springfield?

Since I own a G4003G, I can give you some specifics.
1. The lowest rpm is 70 rpm; this might be a tad fast for threading.
2. The gap gives additional swing of 17 inch total; I'd leave this merchandise to 12 inch maximum only. As a matter of fact, I ground off tapered bolt heads and applied automotive body work to clean up the area above the gap piece. I don't think that Grizzly will guarantee that the gap piece can be re-installed to its former position and dimensions.
3. It is my opinion that the lathe (about 1200 lbs) absolutely be secured/anchored to the floor for safety reasons. The bolt holes' locations (front to back) are about 9 inches; so the lathe is extremely top heavy.

For the most part, I'm happy with it and it does adequate job for me. I am a retired mechanical engineer and I consider myself as a "wannabe" machinist.

Hope this helps.

---Joe

[Harold_V]

I don't think that Grizzly will guarantee that the gap piece can be re-installed to its former position and dimensions.

That's an interesting thought. Any particular reason you feel that way about the issue? I'd think it was made such that so long as there is no junk between joints, it should fit up virtually to perfection. Is it not doweled, or otherwise registered to the bed?

I'd be interested in hearing your comments.

Harold

[ortho]

That's an interesting thought. Any particular reason you feel that way about the issue? I'd think it was made such that so long as there is no junk between joints, it should fit up virtually to perfection. Is it not doweled, or otherwise registered to the bed?

I'd be interested in hearing your comments.

Harold, I agree completely with your position concerning "junk between joints". I believe that gap removal and re-installation would work fine for most high quality lathes that are manufactured to stringent requirements. Other lathes are made so that a typical homeowner won't go bankrupt buying them; these would be a lower quality types. One lathe manual states that gap is installed and ground for close fit and alignment. In addition, some body forces would be applied at the factory, so gap replacement to its exact original position would be impossible. Therefore, this manufacturer would not recommend attempting to replace the gap. Bummer, isn't it?

[Harold_V]

this manufacturer would not recommend attempting to replace the gap.

Unbelievable! In my wildest imagination, I can't conceive of a builder offering a feature that can't be used.

Thanks for the explanation. It makes sense now (although not, really)!

Bummer, isn't it?

Heh! To say the least!

Harold

[mechanicalmagic]

Gentlemen,
I've had the gap out of my G4003 a couple times. I had no issues getting it back in place, but I am (maybe) a little above your average user. And certainly have some patience.

I would not hesitate to remove the gap again, but I'm also the kind of guy that will kick a tailstock over, just to show somebody how to put it back. Just another adjustment.

Dave J.

[Harold_V]

How is registration accomplished, Dave?

Harold

[mechanicalmagic]

Harold,
The gap insert is held down with 4 pretty large Metric cap screws. The gap is kept from sliding front to back with two stubby taper pins (threaded and nutted in the pict).
IIRC, the bed was rough ground, in the gap, and the underside of the gap was also rough ground. I'm sure they were assembled, then the lathe bed fully ground.
I probably verified the gap insert position with a .0005" DTI, been a while.

G4003 gap

Got 4 cap screws holding it down, and 2 short tapered pins.

Different view.

At least that's the best my old memory can do without pulling it apart.

Dave J.

[Harold_V]

That's more than enough, Dave, and, to me, indicates it should come apart and go back together within reason. However, you're at the mercy of the guy that fit it up the first time. If he had it perfectly clean, and free of dings, it should be capable of being removed and replaced within tenths of position, if not closer. The problem is, assuming that isn't the case, that the casting(s) have moved in time, relaxing stresses, and/or the surfaces were not perfectly clean upon original assembly.

Thanks for taking the time. Helps me better understand how the gap works.

My Sag 12 Graziano has a natural gap. While it's a 12" lathe, it is capable of turning 17+", although not very long in length. They accomplish that by having the ways for the carriage well below the ways for the tailstock, which stop short of the headstock. It has proven to be a valuable feature on more than one occasion.

Harold

edit:
I noticed the soft jaws. Great setup. I don't know how others get along without them.

[stevec]

I too, noticed the soft jaws, are they alu? I'm seriously thinking of using soft jaws but my 12x36 chuck has one piece jaws so I guess I could only make some up for my 16x60 which are two piece, right?

[RSG]

Great illustration Dave. There is one cap screw facing the headstock (same as mine) I can only assume it's used to pinch the gap plate back up tight to the ways when re-installing it. Is that the case?

BTW, I too noticed the soft jaws. I rarely use my four jaw now I have them. I actually built it from my 10 x 18 lathe from a 5" chuck and recently sold the lathe minus the chuck LOL, I went a bought a replacement for the guy.