climb vs conventional milling

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curtis cutter
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climb vs conventional milling

Post by curtis cutter »

Gregg
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Harold_V
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Re: climb vs conventional milling

Post by Harold_V »

"During Conventional Milling, the cutter tends to dig into the workpiece and may cause the part to be cut out of tolerance."

By its nature, conventional milling causes the cutter to deflect **away** from the cut. If the part is out of tolerance, it's not because it has been gouged too deeply. The condition described is one that represents climb milling, not conventional milling.

Even machines with standard screw and nut design benefit by climb milling, although generally only as finish cuts, where cutting pressure is greatly reduced so the cutting action doesn't cause the part to self feed.

Climb milling has become acceptable BECAUSE of CNC operations. Those who use manual machines should be selective in when to do so.

While I agree with some things said, if that article was written by an engineer, it's clearly by one who has no machining experience.

H
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NP317
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Re: climb vs conventional milling

Post by NP317 »

Harold wrote:
"if that article was written by an engineer, it's clearly by one who has no machining experience. "

Just think government regulations!
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ctwo
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Re: climb vs conventional milling

Post by ctwo »

I think the article has an unintentional error in the quoted part. I'm sure the writer meant climb milling as that's the subject of the paragraph, which is contrasted by the second paragraph on conventional milling. It's a brief article.
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Harold_V
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Re: climb vs conventional milling

Post by Harold_V »

One thing I hadn't considered is that the cut may be with the full diameter of the end mill. In that case, there is both climb and conventional cutting, and the end mill can cut a part undersized, depending on the direction of feed, where which side is climb changes. Good machining practice would dictate rough and finish cuts, so that shouldn't be a problem. If that's the case at hand, it should have been mentioned.

A pocket (or window, if you prefer) can be machined without leaving telltale signs of undercut in the corners if the pocket is roughed within three thou by conventional milling, then taken to size by climb milling. The opposing slide is eased off a touch as the end mill enters the corner, which helps eliminate chatter and leaves a perfectly smooth transition. The fine finish cut prevents hogging (self feeding) and leaves a superior finish, as the article claims. That has always been my method of operation running manual mills.

H
Wise people talk because they have something to say. Fools talk because they have to say something.
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