What is acceptable chuck/leadscrew/etc...runout? Quality?

[Pitchfire]

After placing and receiving a rather large order from various vendors, most notably Grizzly, including a G0602 lathe and G0619 mill, I am left to ask what should be acceptable runout (and quality for that matter)?

Initially I measured .003" TIR on the G0619 mill chuck and replaced that with an Albrecht chuck that took care of that nicely. Everything else has been remedied with the mill (marred drawbar cover, stuck oiler ball, corroded battery in the spindle depth readout) so I'm happy with it. I can accept that level of runout (and quality).

The lathe spindle had no perceptible runout to speak of which is it's saving grace (plenty of sand in the castings and paint over oil and grease and other issues). On the 3-jaw chuck it had .013" TIR and they replaced that incrementally to where after my machining the inside and outside shoulders on the new backplate, it is down to .008" TIR (.007" on the body) which might be bettered slightly by loosening the backplate and tapping it over (I didn't drill and tap the backplate, they did, so there were limits to begin with there and of course inherent in the chuck). The (first) 3-jaw backplate initially had .001" TIR. The 4-jaw is somewhat unimportant since it has independent jaws and the backplate had .006" TIR, the chuck body .008" TIR. The leadscrew however had noticeable wobble (I measured it and found .020" TIR) and after reading about banding issues etc... I decided to report it and they had me send it back. (I sent the collar with it and got one without, so it was a incremental replacement as well). After receiving the new leadscrew and later collar, and drilling them both for the roll pin and shear pin on the mill, deburring, and installing it, I now measure .015" TIR on the replacement (hey at least it's better right?). I have treated everything with kid gloves and didn't lift with the leadscrew in place etc... (I actually measured it while it was on the pallet).

Additionally the 6" rotary table kit was pretty poor quality (which they offered to replace to their credit). The degree indicator pulled right out and was slanted to start with, so I just scribed a new line and called it good enough. The spring washer that holds the sector arms in place was malformed and gouged the sector arms upon insertion, so I turned the tips up and it works rather roughly (I'll fix that later).

Even the South Bend 4" lock down vice paint cracked and flaked off the first time I clamped it down with a t-slot nut and stud, washers and a nut on top. The vice is otherwise very high quality and I can live without the pretty paint, but I expected better (don't think Glacern's identical vice suffers the same problem?)

I was impressed with the South Bend 16 piece Q/C R-8 collet set. The Aloris Q/C AXA tool post and holders are nice and good quality. I like the Laser center/edge finder from SDA. The Albrecht chuck. And the DRO's guys were awesome in working with me, and their product (yet to be installed) appears to be of very good quality.

Perhaps I expected too much from Grizzly? I have to say that they didn't give me one iota of hassle in replacing parts. I feel for those tech service guys because I realize a lot of it is out of their control. I am left wondering exactly why the U.S./Europeans cannot compete on price and quality, all things considered.

In the end it is all working now and if I run into banding/issues from the leadscrew runout, I'll just deal with it and not use the non-precision stuff for precision work etc...

Was I expecting too much? Have others encountered similar tolerances? What is/or should be acceptable?

 

[Ray C]

I interpret this as two questions... One is how much allowance/tolerance do I give manufacturers in their products before being unhappy -and the other is, how tight do I setup the equipment to do good work.

Seems like you have a good notion of what you're not happy with -and I basically agree with you. If you paid big bucks from a name-brand dealer, the slack you cut should be smaller. If I buy a $30 gizmo that normally cost $100, I don't get too upset if it's not up to par.

My lathes, mills and all their various precision surfaces... I want them to be capable of near perfection -not necessarily saying I always adjust them to that high standard. Also, for the work I usually do, holding a thou is about all that's required and when I get into that type of work, I spot check the various runouts and adjust until things are within +/- 0.00015 or 0.0002. It really depends if there's the possibility of "error stack-up" whereby a whole bunch of things that are just a tad off end-up with total imprecision in the final item. Most things aren't that touchy. It all depends. If you're making something that's only 1/4" big, then you might need to worry about that half-thou. If it's something 2 feet long, it often doesn't matter because nobody has measuring tools that read that tight at those sizes.

After placing and receiving a rather large order from various vendors, most notably Grizzly, including a G0602 lathe and G0619 mill, I am left to ask what should be acceptable runout (and quality for that matter)?

Initially I measured .003" TIR on the G0619 mill chuck and replaced that with an Albrecht chuck that took care of that nicely. Everything else has been remedied with the mill (marred drawbar cover, stuck oiler ball, corroded battery in the spindle depth readout) so I'm happy with it. I can accept that level of runout (and quality).

The lathe spindle had no perceptible runout to speak of which is it's saving grace (plenty of sand in the castings and paint over oil and grease and other issues). On the 3-jaw chuck it had .013" TIR and they replaced that incrementally to where after my machining the inside and outside shoulders on the new backplate, it is down to .008" TIR (.007" on the body) which might be bettered slightly by loosening the backplate and tapping it over (I didn't drill and tap the backplate, they did, so there were limits to begin with there and of course inherent in the chuck). The (first) 3-jaw backplate initially had .001" TIR. The 4-jaw is somewhat unimportant since it has independent jaws and the backplate had .006" TIR, the chuck body .008" TIR. The leadscrew however had noticeable wobble (I measured it and found .020" TIR) and after reading about banding issues etc... I decided to report it and they had me send it back. (I sent the collar with it and got one without, so it was a incremental replacement as well). After receiving the new leadscrew and later collar, and drilling them both for the roll pin and shear pin on the mill, deburring, and installing it, I now measure .015" TIR on the replacement (hey at least it's better right?). I have treated everything with kid gloves and didn't lift with the leadscrew in place etc... (I actually measured it while it was on the pallet).

Additionally the 6" rotary table kit was pretty poor quality (which they offered to replace to their credit). The degree indicator pulled right out and was slanted to start with, so I just scribed a new line and called it good enough. The spring washer that holds the sector arms in place was malformed and gouged the sector arms upon insertion, so I turned the tips up and it works rather roughly (I'll fix that later).

Even the South Bend 4" lock down vice paint cracked and flaked off the first time I clamped it down with a t-slot nut and stud, washers and a nut on top. The vice is otherwise very high quality and I can live without the pretty paint, but I expected better (don't think Glacern's identical vice suffers the same problem?)

I was impressed with the South Bend 16 piece Q/C R-8 collet set. The Aloris Q/C AXA tool post and holders are nice and good quality. I like the Laser center/edge finder from SDA. The Glacern integral shank face mill is a work of art, as is the Albrecht chuck. And the DRO's guys were awesome in working with me, and their product (yet to be installed) appears to be of very good quality.

Perhaps I expected too much from Grizzly? I have to say that they didn't give me one iota of hassle in replacing parts. I feel for those tech service guys because I realize a lot of it is out of their control. I am left wondering exactly why the U.S./Europeans cannot compete on price and quality, all things considered.

In the end it is all working now and if I run into banding/issues from the leadscrew runout, I'll just deal with it and not use the non-precision stuff for precision work etc...

Was I expecting too much? Have others encountered similar tolerances? What is/or should be acceptable?

 

[Pitchfire]

That's good to know.

Not much bothered me about it, but I did expect better and certainly to have castings cleaned before assembly and paint. Everything was full of grit including the chucks inside the backplate. Seems like that's something anybody could pull off even a 3rd world country under primative circumstances. Believe me I know how hard it can be to keep stuff clean having worked in diesel mechanics for years, but we did.