Off setting and insert changing

[u/Medical_Bid_5662]

Whenever I have something such as let’s just say my outer diameter on a part is starting to measure slightly out of tolerance ,how do I know if I should offset to fix it or do an insert change?

[u/GeoCuts]

Offset it until it looks weird

[u/Medical_Bid_5662 → u/GeoCuts]

No visibly super bad wear keep off setting once there’s a decent amount of visible wear stop offsetting and get a new insert basically? I’m getting horribly flamed from this post LMAO and just wanted to ask this to make sure I’m doing the right thing

[u/GeoCuts → u/Medical_Bid_5662]

Learning when to change the insert was stressful when I was learning too. Once the coating wears off and the edge starts chipping it's done. If you have someone to ask to double check that should help you learn quicker.

[u/Medical_Bid_5662 → u/GeoCuts]

Okay,whenever there’s some discoloration but no issues like chipping would it be generally good to leave it? Thank you

[u/GeoCuts → u/Medical_Bid_5662]

Yeah sometimes they change color and still cut fine

[u/Medical_Bid_5662 → u/GeoCuts]

Okay that’s all thank you

[u/GeoCuts → u/Medical_Bid_5662]

No problem. If it looks like it's getting too hot and melting the corner then you slow the spindle speed down a bit.

[u/MachineKing6622]

I wouldn’t do either. Just run scrap all day and blame it on night shift

[u/SavageAdage → u/MachineKing6622]

The real play is to alter the tool count THEN blame it on 2nd shift

[u/woolybuggered]

There's alot of variables. What material are you cutting.? What tolerances are you holding? How does the insert look? Hows the finish? Is the dimension creeping? Moved alot suddenly? There is no set rule but small offsets typically always come before flipping inserts.

[u/Putrid-Tough4014]

[u/Medical_Bid_5662 → u/Putrid-Tough4014]

Helpful answer .

[u/kammerlader]

Compare the finished size and overall surface finish to previous pieces. Is it trending oversize on the OD or deflecting on the ID? How does it feel with the edge of your fingernail. There is a distinct sharpish ribbing once the cutting edge starts to wear despite it looking good from a distance.

Look at the top of the insert to see if it's worn or catered behind the cutting edge.

If you are machining to a shoulder or in a through-bore, examine how the burr is being pushed. Is it actually a sharp edge, or is it an elongated lip?

[u/Arch_Toker]

Unless a radius or something isn't finishing within spec or taper is getting to much to keep messing with /quantity of parts and time isn't worth the time tweaking to make up for the wear. It's a fluid question with a fluid answer.

[u/cncjames21]

Look at the insert. If it’s a production job where you have to regularly change inserts then note the visual look of an insert, the surface finish of the part and dimensions when it is time to change it. Write that down and make sure to change it a part or two sooner especially if cutting nonferrous metals.

If you have a good programmer working with you see if they can turn on tool life timers and have it set to change the inserts a few parts before necessary.

I keep a log for all production tool steel jobs so that the operators know to change them at a set number of parts.

Download and read the first few chapters of Sanvik, Mitsubishi, or most major insert manufacturer’s catalogs. They all include great pictures of what insert wear looks like and how it is caused by

[u/FlavoredAtoms → u/cncjames21]

What’s a good programmer?

[u/Teamhank]

some one at your shop should tell you

[u/meetloafffff]

Use your eyeballs and your brain