Clapped out & Climb vs Convential Milling

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Hukshawn

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I was reading something someone posted about a clapped out Bridgeport.
What does that mean exactly?
Just worn out? Sloppy bearings? dovetails that won't tighten? Slop in mating/sliding serfaces? Etc.
Why would they have said that climb milling is NOT a good idea?
Just curious.
 
Shawn,

You are right, simply saying a machine is "clapped out" isn't specific enough.
It does mean worn and sloppy, but as you ask where is the slop?

Hukshawn said:
Why would they have said that climb milling is NOT a good idea?
Click to expand...
Climb milling has the tool rotating in such a way that it tries to pull the work into the tool. If you have worn lead-screws/nuts and or dovetails the tool rotation can pull the work in. In the best case that can mean chatter and rough finish, in the worst case a broken tool from trying to take to deep of bite.

-brino

EDIT: As has been pointed out below the true "worst case" is worse than I stated above. It can result in the work piece being ripped out and thrown at you, and/or the machine damaged beyond economical repair.
 
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Great question!
And I may have been the one to use the word.
Clapped out to one person means completely usable and/or rebuildable to another.
Really depends on the tolerances you require to do your work, and your ability, interest and time available to rebuild.
I'm not sure that anything is completely unsalvageable.
A few years ago I had a 1984 1ton Chev pickup. Huge in-line 6, and a three speed with the low-low gear (for heavy pulling under 5mph).
Lots of miles.
The floor in the cab was completely gone the box flapped in the wind, couldn't add oil fast enough.
I gave her to a guy who wanted a project and a .
She had some years left in her. I just didn't want to mess with her.

Daryl
MN
 
It wasn't on here. And it wasn't so much reading. Not sure why I wrote that.
I was watching a video of AvE. He said his mill was clapped out and did NOT recommend climb milling.
 
I have seen things happen on worn out leadscrew machines. Such as not only breaking end mills, but parts being pulled out of vises or completely out of clamps and flying off the machine. Heads needing to be trammed again because they moved. Bits of broken end mill hitting people in the face.
That's why it can be dangerous to climb mill with a worn leadscrew if taking too much of a bite. So always be careful when climb milling.
 
Billh50,
Is it true that climb milling is harder on cutters (horizontal and vertical) regardless of machine condition?

Daryl
MN
 
That is something that depends on many factors. Machine rigidity, sharpness of the cutter, amount of cut, etc.
I myself only use climb milling as a finish cut. And then no more than .005 of a cut on a good machine with very little backlash.
 
The explanation I got was that when regular milling, the individual teeth momentarily skidded along the surface before there was enough pressure to 'bite.' Climb milling they had solid material to bite into, therefore climb milling was easier on the individual cutting surfaces than regular milling. Logic says this may be right, I have no experience with that level of study.
I'm with Bill on finish cuts. It leaves a much cleaner surface.
 
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