[allenp]

Hi.

I'm working on that mill as an operator and our company is still young on cnc machining so there is general disagreement about milling parameters.

Some people say there should be smaller depth of cut (axial), some say there should be larger, some say these rpms and feedrates, others say those....

Yes there are catalogues, software tools and recommended data from manufacturers, but people with more experience in company say they have tried with those recommended parameters and that did not give satisfactory results, as in rougher surfaces, more vibration and louder noises.

Generally I'm interested in how to properly determine parameters for steels?

How to know for which tool to select which axial depth of cut and rpm and feedrate for my haas vf2?

I'd like a site or a calculator for that given machine to help me whenever I need, or if you can give me directions on how to calculate those using known parameters like tool type, length, diameter, no of flutes and workpiece material.

Thanks.

[BigNizzy]

I find book speeds and feeds a good starting place, but remember they are based on a rigid machine,rigid setup, short tools and 15 minutes of tool life. With a shallow depth of cut you can increase your feed rate, worth looking at high feed milling. you can use trocoidal milling for a high depth of cut, low width. Get to know your machine and your tooling and you will be able to work out what you can do. Even better get a tooling rep in and try his speeds and feeds on your jobs with his cutters

[WallyL7]

I find book speeds and feeds a good starting place, but remember they are based on a rigid machine,rigid setup, short tools and 15 minutes of tool life.

15 minutes of tool life?

[BigNizzy]

15 minutes of tool life?

Yes, for example the Seco solid end mills catalogue That I have in front of me tells me..

JS553100Z3.3-SIRON-A end mill Slotting on 4130 steel 10mm deep should run at 120m/min (4460rpm) 0.07mm/tooth (935mm/min) feed. Running at those speeds and feeds as long as everything is short and rigid the tool will last 15 minutes. After that you throw it in the scrap carbide bin for recycling.

If you want it to last longer, slow it down.
If you have a setup that not very rigid, slow it down.
If you have a long tool, slow it down.

[WallyL7]

Yes, for example the Seco solid end mills catalogue That I have in front of me tells me..

JS553100Z3.3-SIRON-A end mill Slotting on 4130 steel 10mm deep should run at 120m/min (4460rpm) 0.07mm/tooth (935mm/min) feed. Running at those speeds and feeds as long as everything is short and rigid the tool will last 15 minutes. After that you throw it in the scrap carbide bin for recycling.

If you want it to last longer, slow it down.
If you have a setup that not very rigid, slow it down.
If you have a long tool, slow it down.

"After that you throw it in the scrap bin" ...that is pretty funny to put in a catalog...

I haven't really paid any attention to any company actually stating a time for tool life since you may never have a job that mirrors their test results. I'd add an even larger variable to your list of "everything short and rigid"...and that is what machine is it on? I can often get 2-3 times the life out of tools on my Mazak vs my Haas with identical setup and program feeds/speeds...

[BigNizzy]

The Mazak will be more rigid than the Haas so you would expect better tool life.

It's also worth pointing out that tooling costs are negligible. Time is the biggest cost. If a tooling manufacturer comes out with a new coating that doubles the life of a tool or an insert they will ramp up the speeds and feeds to increase the MRR and bring the life of the tool back down. As for stating a time the 15mins thing seems to be an industry standard that nobody shouts from the rooftops. You have to tease the information from a tool rep.

As a general rule of thumb I use the manufacturers surface speed as that relates to the coatings. If I have a long tool I dial it back to 70% if I am finishing I pull the feed back to something like 0.025mm/tooth but you really have to take each job on it's own merits, throw in your own experience and you will get somewhere.
One thing I do run at manufacturers data is drilling. Never had a reason not to.

[Geof]

JS553100Z3.3-SIRON-A end mill Slotting on 4130 steel 10mm

Is this hardened or annealed, and is this dry cutting with an air blast or flood coolant? The conditions you describe are not really extreme and I am surprised the tool life is only 15 minutes.

[WallyL7]

The Mazak will be more rigid than the Haas so you would expect better tool life.

LOL Yeah no kidding...but my point is...did the tool maker run 15 minutes on a Haas or on a Mazak? :wee:

I think you are posting generally good info though...but it is clear the OP could care less...

[BigNizzy]

They probably ran it on a small sturdy machine, clamped to the table using the best of everything, Material is hardened and tempered. Agree those speeds and feeds are nothing amazing it's at the cheaper end of the market. I just happened to be using one 5 mins before I posted.

I know it's turning related and not milling but if you look at Secolor you will see the 15mins tool life. Don't get to hung up on the tool life if you want to run longer get a tougher grade and slow it down. we did some turning with ceramic inserts on Inconel 625 at 300m/min and the insert lasted 1 pass (from memory it was something like a 400mm in cut) before it had to be turned as it was shot. The operators hated it because they had to turn the tip all day, they preferred carbide cutting at 35m/min with half the depth of cut and feed/rev because they got to sit on their backside watching it.

[allenp]

I'd like to know for example for shell mill diameter 32mm, 5 teeth, how to know when the mill makes contour passes with width of cut ae like 2-4 mm and depth of cut 1-1.5mm?

if I use formula, the recommended data from manufacturer of teeth says it'd be 1800rpm max and 720mm/min feedrate, but it feels too slow and vibrates more than when I use 4000rpm and 2500feedrate which feels smoother and is a lot faster, but how to know if it's worse for the tool?

is there a corelation of feeds and speeds with width and depth of cut and if there is, what is it?

thanks.