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What’s your troubleshooting order after a scrap a part?

Alan

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Everybody scraps parts sometimes, but the difference is what you do in the first five minutes after you realize it. What’s your default move now, check the setup, review the program, or step back and change the process, and what clue makes you pick one path.

Some folks swear it’s setup and workholding first because that’s where sneaky mistakes hide. Others go straight to the program and simulate, or they look at the process like tool choice, feeds and speeds, coolant, and chip control. Where do you start, and what do you consider “fast enough proof” before you touch anything.

Drop your order and a simple example. Like a time you thought it was code but it was actually a clamp, or you blamed the setup but it was an offset or a tool length issue.
 
I start with setup and workholding every time because clamps and parallels can lie. I look for witness marks, chips under a jaw, and anything that could tilt the part. The example that burned me was blaming code when a tiny chip under the part lifted one corner and the finish pass went ugly.
 
I start by asking what changed since the last good part. New tool, new insert, new vise stop, new program edit. If something changed, I review that first. My proof is comparing to the last known good setup sheet or notes, even just a quick photo.
 
If the scrap is consistent, like every part is off the same way, I look at the process next. Feeds and speeds, tool wear, and chip packing. If it’s random, I go back to setup. My fast proof is doing a quick test cut on scrap or air cut to see if the tool path is doing what I think it is.
 
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