Edging – peripheral milling

[metalworkerr]

Hello

Thank you for entering in my post

I am currently machining mild steel plates 1400x700x50mm.

They do not have a normal rectangular shape, and they have been laser-cut by leaving 4mm of material each side
I need to machine all this profile first, and I am using this 50mm Iscar shoulder end-mill (90 degrees) here on this link
ISCAR Cutting Tools - Metal Working Tools - H490 F90AX-17 : 3104418 - H490 F90AX D050-4-22-17

I am machining these plates on a 8 meters bed CNC milling with a cad/cam program, which cannot be modified, made by my team-leader.
He did set the following parameters: cutting speed 1200rev/min, feed 1500mm/min, cutting depth 2mm; so 25 passes and it takes very long to machine all this profile.

I my company to do profiles, we do always set a small cutting depth between 2 to 3mm and we put a high feederate, I do the same too, since I was taught in this way when I had my apprenticeship.

I know that a maximum chip thickness is the most important parameter for achieving a productive and reliable milling process.
Which would be the best parameters to achieve the maximum chip thickness on this job?
Could I set a 15mm cutting depth, or at least more than 5mm?

I know that using a bigger cutter would help to increase the chip thickness, and I do also have 125mm Iscar shoulder mill with exactly the same tips of the 50mm-one (see link above), could I use it to machine this profile?

In my company they never use extended flute cutters for profile milling, even if we have some of them, (I did put an example on this)
link)ISCAR Cutting Tools - Metal Working Tools - H490 SM-09

Which is the most productive way to machine these profiles?

Any suggestion according this matter will be very appreciative

Thank you in advance for your support

 

[ornerynorsk]

What is the tolerance that you must hold? Laser scale can be very abrasive to cutters. I would be inclined to try a long end mill of at least 50mm diameter, milling the periphery in ONE pass, conventional feed, not climb milling. Of course, your feed and rpm may have to be adjusted. Slow or fast is merely a perception, it is the metal removal rate or the time it takes to complete the entire job that matters. Often times, high speed and high feed is most efficient, but not always.

A cutting depth of 2mm on a 4mm periphery is not even coming close to using the capability of the machine or the cutter, and with 25 passes, the edges of the insert are being worn away prematurely.

It is better to have enough ideas for some of them to be wrong, than to be always right by having no ideas at all.

 

[tbuelna]

I would agree with ornerynorsk in that the recast layer from laser cutting is very abrasive. You would be better off using CNC water jet to rough cut the plate.

As for the most efficient type of milling cutter available to profile the steel plate, have you considered this particular ISCAR product that uses replaceable carbide inserts.

 

[ornerynorsk]

tbuelna, perfect suggestion. These are great cutters, have used them many times. Waterjet would also be a good choice if the accuracy/cycle time would allow it.

It is better to have enough ideas for some of them to be wrong, than to be always right by having no ideas at all.

 

[metalworkerr]

Thank you very much indeed Great Teaching