[rktman8888]

Anyone experienced this one,... When profiling with a Haas 2013 SMM2. My parts have a stripe about half way down the wall. You can't feel the line but the finish is two different colors. Basically two tone looking parts. Tried different holders, tools, materials. Aluminum seems more noticeable than stainless. Typical finish pass here is 3,000-4,000 RPM with a .001cpt feed rate. It does it in both X and Y.
Thanks

[Machineit]

I have no idea what you are talking about, but enjoy the hell out of the Sites attempts at giving us "Similar Threads."

:wee:

I would check the endmill though. Is it coated and some more worn off? Otherwise it is probably a endmill wear issue and an optical illusion.

Mike

[Matt@RFR]

Otherwise it is probably a endmill wear issue and an optical illusion.

That's what I was thinking as well. "Color" is an odd way of describing it though. If that is the case, it's just a dull or chipped area on your endmill. The only way you'll get away from this 100% is to use dedicated finish tools.

[utengineer04]

why not just profile the part out and leave .005 - .01" on the profile then take a finish pass at full depth and hopefully you won't see the color change. I would say it has something to do with the endmill side pressure, kind of like taking spring passes on a lathe. Hope this helps.

[rktman8888]

Thanks for the replies. I do use separate finish tools. I normally cut full depth when roughing using HSM tool path. Then take a .005" fin pass. It's odd,.. the lower part of the cut is darker looking then the upper part. Almost like the part was cut with two step downs. At first I thought it was the material. This is my profession, been machining since 2000. Never have seen this before. Not all that noticeable in stainless. Aluminum its very noticeable. I have been thinking about what else I could trade this mill out for. Problem is,.. They hook you with the control and probe. Makes setup fast and effortless. I may bring one of my parts over to the local spindle service shop, they may know something?

[cygnus x-1]

Can you post a picture of the part showing the color difference?

C|

[WallyL7]

I would check the endmill though. Is it coated and some more worn off?

Aluminum seems more noticeable than stainless.

This is my profession, been machining since 2000.

I can't imagine assuming he runs the same endmill for both aluminum and stainless...and since he has been doing this a long time he must be fully aware of the tool wear line that you guys are thinking it is (which is what I would have figured also)...

Pics are needed...

[cygnus x-1]

Does the look of the part change if you try a heavier finish pass? What happens if you do a zero step over spring pass?

C|

[rktman8888]

Same result with a spring pass. It seems more noticeable when using 4 flute EM. I just got done with a 304SS job. If you hold the parts just right you can see the change in color half way down the cut. It's odd,.. I will try and post some photos. My thinking at this point is some type of resonance going on . 3 flute EM don't seem to do it as much as a 4 flute. I will play with the speeds and feeds some more.

Thanks for the replies.

[cygnus x-1]

Same result with a spring pass. It seems more noticeable when using 4 flute EM. I just got done with a 304SS job. If you hold the parts just right you can see the change in color half way down the cut. It's odd,.. I will try and post some photos. My thinking at this point is some type of resonance going on . 3 flute EM don't seem to do it as much as a 4 flute. I will play with the speeds and feeds some more.

Thanks for the replies.

Yeah, that's why I asked about a heavier cut. It might dampen any vibration more.

C|

[big_mak]

Is this in pockets where sometimes the light reflected from the bottom of the part can play with the finish appearances. It's goofy, but it can happen.