milling head runout

[madbear]

i have been having some problems with a Grizzly #G0516 lathe combo.
only had the thing for about 3 days & the switch went out . about 3-4 days later i tried to get the draw bar loose, it was stuck & after a lot of taping with both a dead blow & brass mallet it would not come loose. after calling the tec. service dept. the guy told me that they can become really stuck in shipping & that i should hit it harder. well i did,got it out & it was now bent. after talking with them & sending in a video of the wobbling bar they let me send it back to get it repaired or exchanged for another one because i was not at all happy with it & had been trying to get it exchanged.
well i got it back after about 3-4 weeks, opened it & there was not any change made to it.
ok now i am really pissed, called the customer service to find out what was up & was told that there was nothing wrong with it. ok i can live with the draw bar being a little bent if it doesn't affect the performance but it looks like the spindle is wobbling & when i told the lady about it she said that it was checked by the tecs. said that it was acceptable!
now i admit i am not a machinist but i have been working with woodworking machines all my life & have my own wood shop ( furniture & cabinets) & that just doesn't add up.
how much wobble should there be in a "precision" mill spindle?
thanks for reading my rant & any advice would be appreciated;
madbear

[Boostinjdm]

How exactly did you determine the spindle is wobbling?

[jep24601]

Are you seeing the drawbar on top of the spindle wobbling or are you measuring spindle wobble at the bottom end of the spindle?

[madbear]

at first i just eyeballed it but i just went out & put the dial indicator on a 1/4" endmill & it showed to be 2,000 out.

[macona]

You are measuring wrong. You need to use a test indicator on the internal taper of the spindle.

[madbear]

will check it tomorrow
thanks

[philbur]

I think this thread may need to rewind to step one. You talk about a wobble and a video and endmill run-out.

If the hole in the top of the spindle is larger than the drawbar diameter (as they always are) the drawbar will not necessarily align with the spindle axis and therefore will appear to wobble when rotated. This might be interpreted as a bent drawbar.

The best way to determine if the drawbar is bent is to roll it on a flat surface.

Run out measured on an endmill can be due to a number of reasons, one of which is not a bent drawbar.

When seeking help it is best to state what you know for fact and how you determined it to be a fact. Don't make you own diagnoses and then state it as a fact, it can lead to lots of confusion.

Phil

[philbur]

Put the video of the wobbling drawbar on youtube then post a link here.

Phil

[madbear]

philbur,
you are right, i shouldn't state for a fact something i don't know for fact. i was not aware that i stated it as a fact, sorry! here is a video link to the video i sent to grizzly *(hope it works)
you can see why i thought it was bent & notice the "wobble" on the spindle nut.
as i said this is just one of the problems. i am having trouble with the gear train & i don't know where the squeal is coming from.
now i understand this is not a machine that an experienced machinist would buy. it is a hobby type lathe combo & i can't expect it to do what a larger more expensive machine wiil do.
sorry if i seem to be a little whinner. i am just trying to figure this all out. i will be talking to a grizzly tec. latter,see what he has to say. it just seems that this machine is not very well built.
i guess i will be stuck with it so will keep researching, learning & buying what i need to fix it or make it run better
thanks for all the help;
madbear


http://youtu.be/INJKmQpM2Zs

[gwilson]

You'd best not run the machine much at all,or that squeal may turn into a worn out part in a big hurry.