Question for G4003G owners

[Dman1114]

What type of cutters is everyone using ? Also how would u rate the finish your lathe produces?

 

[drs23]

What type of cutters is everyone using ? Also how would u rate the finish your lathe produces?

I mainly use indexable carbide inserts in 5/8" holders. I have some HSS that I use mainly for chamfering but a few for turning plastic as well. As you get more accustomed to your machine and experiment with feeds and speeds you'll find what works best for you.

Generally the carbide like a higher speed and DOC but I've made finish passes with carbide very satisfactory as well.

You just have to dive in and experiment.

 

[Earl]

What type of cutters is everyone using ? Also how would u rate the finish your lathe produces?

I have both a heavy 10 and a Grizzly 4003G. I use HSS tooling for both machines. The finish was terrible on the Grizzly. I really believe that was the reason that the guy sold it.
my first experiment was to take the bits that did a good job on the Heavy 10 and use them on the grizzly - still terrible finish. Next, I loosened up the belts. I now can move them about an inch and a quarter - inch and a half. Finish did improve but only slightly. Finally, I put a .0001 dial indicator on the cross feed slide and was shocked by the amount of endplay in the spindle. With the end cover off the lathe, I could grab the spindle with my hands and pull and push it past both ends of the indicator! I switched to a .001 and noted about 11 thou endplay!!! I thought I had forgot to lock the carriage (where the indicator was mounted) before the measurement but no, it was locked up solid. Per the manual, I ran it to warm it up, then tightened the take up nut (using a hammer and chisel - again per the book) to the point where I could not see any movement on the indicator. Then I switched back to the tenth indicator and tightened the nut a little at a time until I could not see any more movement on the indicator. I tightened the keeper screws in the take up nut and ran it at high speed for over an hour. The bearings heated up a bit but it was not uncomfortable to the touch. Since that time I have also switched out the motor for a 3 phase and added a VFD. I can run the thing down to about 30 or so RPMs up to around 2000 if I want to. Some fine adjustment of the speed control also improves the finish. I neglected to state that the material that I was cutting was stainless gun barrel stock. It is drops from chambering Kreiger rifle barrels. I believe it is 416.

Bottom line here is that the bearing pre-load was non-existent. The easiest way to check it with out indicators is to run it at high speed for 15-20 minutes and check to see if the machine warms up around each end of the spindle, If it is cold, you need to go thru the process in the manual to adjust the preload, the bearings should get warm but not hot.

 

[dave2176]

I use indexable inserts purchased from Shar's for most things. Some HSS for special shapes. I'm getting a mirror finish on aluminum and quality steels like 4130 and 4140. 1018 does not give a good finish unless you file or sand it.

Dave

edit: Make sure the metal you are testing with is able to give an acceptable finish for your testing so you aren't needlessly disappointed.

 

[gdu]

I have a G4003 which is basically the same lathe. I use carbide tooling from Grizzly most of the time. I use HSS with interupted cuts.

No problems with finish with either.

MK

 

[Ulma Doctor]

I don't have a grizz, but i have it's sister a Shenwai SW900 12x36.
I use both HSS and Carbide Tooling, it works like a dream with either.
as others have mentioned, correct tool positioning in regards to being on center, feed rate, and spindle RPM are critical to good finish.
slower feed rates generally produce better finishes.
lubrication of the machine and the work will produce better results.
good luck!

 

[Walsheng]

I have been running mine for a few months and have turned cast iron (6"), steel (3"), aluminum, brass and I the finishes I get are pretty darned nice. I have used HSS, carbide inserts and brazed carbide.
The only issue I have had is the loose nut on the handle! By that I mean selecting the correct cutter, speed and feed. The bottom line is the machine is not dependent on a particular cutter to get a good finish. If you are new to lathes get some HSS bits and grind them up. It will teach you quite a bit and it will be worth it down the line, especially when you get into a situation where you need a special shape.

John