Having Issues with VF2 - Not cutting properly!

[planeindustries]

Hi,

I am having issues with my VF2 not cutting properly - We have had the machine with very few problems for a couple of years but recently the calibration seems to be off. When I program it to cut a circle, it doesn't give me a clean finish - the same issues occur in the same place however many times I try - Please see the images attached. Parts of the shapes are cutting fine and other parts are all over the place.

We have had a couple of minor crashes over the years as we are new to this - so not sure if it is a calibration thing. The CAM software we use is FUsion 360.

Any help would be appreciated.

Kind regards all

Ben

 

[BajaFire]

Define "minor crash"

 

[EmGo]

I am having issues with my VF2 not cutting properly -

One of the reasons to buy a Haas is service and support. So avail yourself of this opportunity.

 

[planeindustries]

Define "minor crash"

recently the guide ral hit the steel holder on the far wall that the acrylic panel slides into - threw up an error - managed to rehome - it could be due to that - do you think the machine needs recalibrating?

 

[Vancbiker]

Are those the same programs that used to make “good” parts. The pictures show things that could be either program problems or machine problems. Have you checked spindle endplay and axes backlash?

 

[SteveEx30]

What tolerances do you have set in your cam software? Also looks like your pics are ruffing passes, do you not have a finish pass to show?

 

[rjwalker1973]

If you rerun the program does it smooth out any?

 

[BT Fabrication]

doesn't look just like a circle issue. looks like something is loose that shouldn't be like a axis or spindle bearing that is going out and bouncing around or even a holder not properly being pulled into the spindle.

 

[triumph406]

Looking at the first picture I'd be checking leadscrew thrust bearings and leadscrew nut.

Would take 10-20 minutes to determine which is bad.

 

[planeindustries]

If you rerun the program does it smooth out any?

No, I’ve run roughing and finishing passes and get the same thing

 

[planeindustries]

doesn't look just like a circle issue. looks like something is loose that shouldn't be like a axis or spindle bearing that is going out and bouncing around or even a holder not properly being pulled into the spindle.

Very probably, my gut feeling says something is loose from a crash - I don’t think it is a CAM issue - may be wrong but half of the circle seems to machine ok

 

[planeindustries]

Looking at the first picture I'd be checking leadscrew thrust bearings and leadscrew nut.

Would take 10-20 minutes to determine which is bad.

I’ll have a look into that - I’m not sure how to but chat GPT may be able to help - also I think it might be time to get the engineer out for a visit as I don’t think I’m qualified to fix this at this point

 

[BT Fabrication]

Very probably, my gut feeling says something is loose from a crash - I don’t think it is a CAM issue - may be wrong but half of the circle seems to machine ok

is your machine the greased up version that likes to plug all over and starve the ways of lubricant? or are you running the oil?

 

[BajaFire]

recently the guide ral hit the steel holder on the far wall that the acrylic panel slides into - threw up an error - managed to rehome - it could be due to that - do you think the machine needs recalibrating?

Not sure what you mean by "guide rail" or "steel holder."
A few years back I had a nasty wreck (head went DOWN instead of UP while the table was moving) that cracked the Y-axis ballnut on our Fadal...the machine made goofy lobe/oval shaped "circles" when interpolating until I changed the ballnut.
Put a mag-base indicator on your table and position the stylus to read off the spindle. Try to give the table (or spindle) some heave-hoes...if the indicator dances around like crazy (more than a couple thou), the part you're wobbling isn't properly fastened to the machine anymore

 

[triumph406]

Put an indicator on the table, and push-pull the table in both X and Y, will need some force to get a good reading. Push at the center along the axis of the lead screw.
Record that movement which will be the total play in both the leadscrew nut and thrust bearings.

Put the indicator on the end of the leadscrew. Do the same push-pull.
record that movement which will be the thrust bearing end play.

Subtract the second reading from the first, that will be the backlash in the leadscrew nut.

 

[triumph406]

I’m not sure how to but chat GPT may be able to help

Your joking right?

How could chat GPT possibly help?

 

[planeindustries]

Not sure what you mean by "guide rail" or "steel holder."
A few years back I had a nasty wreck (head went DOWN instead of UP while the table was moving) that cracked the Y-axis ballnut on our Fadal...the machine made goofy lobe/oval shaped "circles" when interpolating until I changed the ballnut.
Put a mag-base indicator on your table and position the stylus to read off the spindle. Try to give the table (or spindle) some heave-hoes...if the indicator dances around like crazy (more than a couple thou), the part you're wobbling isn't properly fastened to the machine anymore

Thank you!

 

[MaxPrairie]

What does a G13 cycle look like? Take the never ending Fusion updates factor out of it.

 

[DavidScott]

For one thing it looks like your spindle has lost its bearing pre-load. Are your issues with the pocket floor only or sidewalls too? If you have done finish passes using Contour then you have some real problems there, far more than a little backlash.

 

[planeindustries]

For one thing it looks like your spindle has lost its bearing pre-load. Are your issues with the pocket floor only or sidewalls too? If you have done finish passes using Contour then you have some real problems there, far more than a little backlash.

Yes, that is a finishing contour pass - hence the panic with the issues. I have been having problems with the tool holders going into the spindle correctly recently which has been getting progressively worse - initially, I thought it may be a drawbar issue not pulling the tool holder in enough - when the machine does a tool change it often throws up 'ALARM - TOOL UNCLAMPED'

We have only been machining for 18 months - I have tried to learn the ins and outs of the machine over that time to varying degrees of success but I think I will need an engineer out for this one.