Horizontal mill rigidity

[Matthew Hajicek - Singularity]

We've got an old Kitamura HX300 that we're still trying to hold tolerances on. I put an indicator from the spindle to the top of the tombstone and was able to push the tombstone away from the spindle .007" by hand with my shoulder braced on the frame of the machine. How much movement would you get on your machines with this test?

[Sticky]

Was the movement from the Z axis moving, or the tombstone tilting? Was the machine off or on?

 

.007" is a major problem, .0007" would seem more normal to me, but even that would be a bit much. You need to find out what exactly is moving, and from there come up with a solution.

[mkd]

i would get machinists with smaller shoulders

[mkd]

but seriously, you shouldn't get ANY indication that way. it should be minimal with blocks and pry-bars. a machine tech should be able to isolate where the slop is coming from. if it is a box way machine perhaps the gibs (alternately spelled jib, not sure which spelling is technically correct) can be adjusted.

could also be screws (obviously).

prolly start with b axis bearing check

 

better throw a few thousand bucks at that machine. really, a small price to pay to bring it out of the POS category.

[Machineguy]

Check your pallet lock.

Pull the pallets, check for uneven wear, chips on the bottom of the pallets.

Look B axis over without the pallet. See what the pallet lock is doing.

Put a indicator on B, gently with a pry bar under B, see what kind of movement your getting. This is to see if the pallet lock is working or you have a bearing issue.

Being a older machine it could be a lot of wear in multilple spots. Rebuilding the b axis is a lot of work.

 

Service guys are just down the road from you. OUCH

 

Machineguy

[Newbeeee™]

Nothing to do with this but sort of related, I remember years ago putting a clock on a tool that was in a spindle of a Bridgeport Interact (series 1 BOSS control). You could see +/-.002 easily by just pushing the head up and pulling it down.

Big swan neck design I guess.

Then I put a clock on the rear or a vice jaw (body had been machined away to allow fitting of a c type stop for quick adjust) and give that a squeeze and got .005"...

[Newbeeee™]

Oh and on topic....check the locations for the pallet feet. Have you got air blast that keeps the crap out as this could be blocked.

[K2csq7]

B axis not locking or gib adjustment.

Get the indicator on something other than the B axis (Machine table casting) and do the test again...

I ran a 1981 Matsurra 1500 that would shift about .02

It only gets worse if the root of the problem is not addressed.

[GIZMO 21]

I know on the newer kitamuras you have put the m-code for locking pallet or else it wont lock.

The quick way we knew if it was locked,you cannot turn the pallet with the hand wheel.we would always let mastercam

Output the lockcodes i think its like(m10 unlock and m11 lock).

 

[within a thou]

You may have to tighten the locks on your B axis. There should be a plug in the top of the table. Pull it out get a flash light rotate the table till you see the locks. They will be split so loosen the screws then make a tool to tighten the actual split nut (I just used a shaft that I put 2 dowels in the spacing for the nut welded it to to socket and used extensions to reach down into the table) then tighten the screws again.HTH

[mkd]

so Mat, stop holding out on us.

we got money riding on who guessed correctly.

[Matthew Hajicek - Singularity]

Don't have it fixed yet.

 

The machine was on, the B was clamped, and my shoulder was on the machine frame as opposed to the spindle, so it had to be the tombstone tipping. We've got another machine down waiting for new ball-screws, so we can't mess with this one yet. It does seem to do ok as long as we keep the tool force down.