[Luppy]

Anyone knows the official names for the different types of chip you can get during milling?

http://i.imgur.com/dZ2Hn.jpg

http://i.imgur.com/jS85h.jpg

http://i.imgur.com/hbPPL.jpg

etc

Also, if I'm getting purple-blue colored chips during the milling of inconel, can i assume it's hitting the same temp. as when i get purple-blue chips during the milling of steel?

Any help would be greatly appreciated.

[txcncman]

As far as I know, there are no "official names" for different shapes and textures of metal chips. All you can do is use adjectives to describe them: Small, large, smooth, rough, jagged, sharp, fine, broken, stringy, etc.

[Luppy]

I saw names like segmented, string, helical chips etc and everyone was using them. Ok, I'll try to name them and hopefully no one would laugh at me.

Anyway, I found a study of someone who managed to link the colour of the chips to a temp range. But, it's for steel. Inconel oxidises at an even higher temperature, right?

[txcncman]

I do not know who everyone is. Mama taught me everyone was a fool. Again, words like segmented and helical are adjectives. I had already mentioned stringy. Yes, changing of a material's coloring is based on temperature it has been exposed to as well as oxygen or other gases, or lack of any gases at all, and how quickly it is cooled after heating.

[Geof]

I would refer to them as flaky compressed chips. They look a bit like chips that come off strongly negative rake cutter.

Regarding the colour (please take note of Aussie spelling ) yes, same material, same color, same temperature. I think it is possible that with inconel the color may occur at a higher temperature than that color occurs with steel but I doubt that the difference is very large. I started to type that as far as I can remember purple is about 600 degrees then decided to do a Google and found this: Heat Treatment of Steel

If there is a difference between an alloy steel and inconel I doubt that it is greater than about 50 degrees.

[Luppy]

Thanks for all the help so far.

Picture 1 (top): 1 mm depth of cut, 1 mm width, 0.03mm/tooth, 30 m/min
Pic 2: 2 mm depth of cut, 1 mm width, 0.03mm/tooth, 30 m/min
Pic 3: 3 mm depth of cut, 1 mm width, 0.03mm/tooth, 30 m/min

All done using climb milling and no visible defects on cutter.

[Geof]

Depth of cut 0.118", radial width 0.0394", feed per tooth 0.0012", speed 98.4 feet per minute. (I think in imperial measure)

What diameter cutter? Based on the chip shape my guess is that it is an insert cutter and probably 25mm diameter or larger.

If I was running that cut and produced those chips I would be tempted to run the speed up by about 50%, maybe more. I would also take the radial width up by at least 50% and would probably double, maybe even triple the feed.

If my guess is correct about the cutter diameter you have a large amount of radial thinning on the chip. Your actual chip thickness per tooth will be a lot less than the nominal 0.03mm. To get an actual chip thickness per tooth near this you would need to triple your feed rate. I would expect the form of the chips to change to a tight curl bright purple. Actually they would probably be dull red right at the tool.

It is also possible that by running with these changes I would destroy an expensive cutter so if you decide to do something like this it is your decision and reponsibility.

[underthetire]

I always look for 6's and 9's.