New 728VT Questions

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flutie98

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Hey Folks, I have been setting up my 728VT as a first milling machine and have been having fun learning the basics and fabricating custom DRO brackets.

1) I initially had some issues with my y axis being incredibly hard to turn, PM support suggested adjusting leadscrew retaining plate alignment, gibbs and loosening bolts to stand (can induce twist) all helped but still getting some stiction when trying to make small adjustments. Anything else I should look into?

2) I noticed some coarse machining marks on the y-axis ways on the right side only (pics below). Anyone seen this before? cause for concern or potential cause of (1)?

3) My fine quill feed knob seems to have a detent in one location every complete turn. Is this normal?
 

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I've always checked the ways for flatness and regardless "stoned" all the matting surfaces with any new machine in my shop (new from manufacture or used) and apply fresh way oil. Don't forget to do the same with the gib's. I'd also suggest the mode I wrote about in this thread.
https://www.hobby-machinist.com/thr...-to-correct-it-pm-728-vt.109971/#post-1096755

Welcome to the Forum and good luck with your new machine.

Kenjesse
 
flutie98 said:
Hey Folks, I have been setting up my 728VT as a first milling machine and have been having fun learning the basics and fabricating custom DRO brackets.

1) I initially had some issues with my y axis being incredibly hard to turn, PM support suggested adjusting leadscrew retaining plate alignment, gibbs and loosening bolts to stand (can induce twist) all helped but still getting some stiction when trying to make small adjustments. Anything else I should look into?

2) I noticed some coarse machining marks on the y-axis ways on the right side only (pics below). Anyone seen this before? cause for concern or potential cause of (1)?

3) My fine quill feed knob seems to have a detent in one location every complete turn. Is this normal?
Click to expand...
A) see post #5 https://www.hobby-machinist.com/threads/pm-728vt-stand.110654/
B) use a master level & shim it flat.
C) fill the base of the cabinet with several hundred pounds of lead/sand/rock/steal anything to give it weight.

Can you fell the machine marks with your thumbnail? All the quill knows seen to have a catch in them ....
 
flutie98 said:
Hey Folks, I have been setting up my 728VT as a first milling machine and have been having fun learning the basics and fabricating custom DRO brackets.

1) I initially had some issues with my y axis being incredibly hard to turn, PM support suggested adjusting leadscrew retaining plate alignment, gibbs and loosening bolts to stand (can induce twist) all helped but still getting some stiction when trying to make small adjustments. Anything else I should look into?

2) I noticed some coarse machining marks on the y-axis ways on the right side only (pics below). Anyone seen this before? cause for concern or potential cause of (1)?

3) My fine quill feed knob seems to have a detent in one location every complete turn. Is this normal?
Click to expand...
if the machining marks are below the way surface they are not to damaging but far from what i would expect from a PM T series mill. if they are proud of the way surface they must be cleaned up "stoned". I'm sure the PM will take care of it for you, just keep providing the information to them.
 
55fairlane said:
Feel the machine marks.....I'm sick & I don't feel good. Get off my cloud
Click to expand...
strangely I got that part, it was this that had me scratching my head
"All the quill knows seen to have a catch in them ...."

BTW when i mentioned "stoned" above I was talking about the ways on the mill.:)

and yes i will stay off of your cloud.
 
dabear3428 said:
strangely I got that part, it was this that had me scratching my head
"All the quill knows seen to have a catch in them ...."

BTW when i mentioned "stoned" above I was talking about the ways on the mill.:)

and yes i will stay off of your cloud.
Click to expand...
Lol.... all the quills & fine feed knobs seem to have a "catch" in them ....must be designed into these cheap-o machines.

Who cares about you (?) Or whom ever gets stoned. I do not run in that crowd for a reason I dislike drugs and people who get high .....they spend more time finding new ways to get high, finding ways not to get caught.....put ½ that much effort into being legit and they would have the world by the......

I'm sick. And I don't feel good. I get testy when I don't feel good.......
 
55fairlane said:
Lol.... all the quills & fine feed knobs seem to have a "catch" in them ....must be designed into these cheap-o machines.

Who cares about you (?) Or whom ever gets stoned. I do not run in that crowd for a reason I dislike drugs and people who get high .....they spend more time finding new ways to get high, finding ways not to get caught.....put ½ that much effort into being legit and they would have the world by the......

I'm sick. And I don't feel good. I get testy when I don't feel good.......
Click to expand...
well ok then! hope you get to feeling better soon
 
dabear3428 said:
if the machining marks are below the way surface they are not to damaging but far from what i would expect from a PM T series mill. if they are proud of the way surface they must be cleaned up "stoned". I'm sure the PM will take care of it for you, just keep providing the information to them.
Click to expand...
what stone are you using that will be able to get underneath the dovetail area, to clean up the full width of that way..?
Is there a stone that has the proper angle built in that can deburr both faces at the same time..?

Also I thought I read that those indentations on the ways helped hold way oil, I could be wrong.... I certainly wouldn't stone them unless they were proud of the surface... wouldn't the ack of trying to stone those marks out induce uneven wear to the ways..?

last but not least, I cant tell if 55fairlane is just joking, if not you can borrow my positive energy shield, it will protect you :)
 
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