[tobyaxis]

i m no authority , just a nutjob who isn t scared to push an simple endmill till it breaks , then i back off 10% , time is money and you throw a few worn endmills or inserts into the equation of time saved , the dollars for time saved outway the burned tools cost = more profit + i love to see the chips fly
but once set properly though you d be surprised that when you hit that optimal point the tool life increases from what was concidered safe previously,

we had a run of parts recently that the programmer set spec. speeds and feeds , he sent down a 2 1/2 hr program ,i sent him back a 1 hr program,
yeeha !!!

i think 8000 mm must be one zero too many or it s really soft material

LOL Faster

[joecnc1234]

Why not increase your depth of cut and lower your feedrate. Everyone talks about high speed machining as moving the tool around real fast, how about high metal removal machining if you cut 1mm deep at 8000mm/min you could achieve the same cycle time with 2mm deep at 4000mm/min and have twice the tool life. or 4mm deep and 2000mm/min just use insertable carbide and an air blast.
Joe

[dertsap]

with a greater depth of cut the speed and feed are both lower , depth of cut ,work engagement , and proper tooling has the most affect on the efficiency of a cutter ,also greatly affects the the amount of pressure on the tool which can lead to tool failure ,
i worked at a company making our own product , we changed everything over to high speed high performance, the tool cost decresed while the production rate was doubled if not tripled in many cases , it s all money in the pocket ! in 3 yrs we never lost an insert mill and we put out a serious amount of product , what brought it all on was we were looking at farming out parts because we couldn t keep up ,end result was we did it all and had time to relax

the job i was refering to in my previous post is a sleugh of parts that we got in that are 75% stitch milled with various sized ballnose cutters which aren t designed to be hogging material , most of the excess had been removed with insert mills ,
as far as material removal rate goes ,knocking 1.5 hrs off a normally 2.5 hr cycle is an increased material removal and at $85/hr on several orders of 50 parts adds up
bottom line is if a guy knows what he is doing then it comes easy as far as bumping up production , if a guy doesn t know then there are a lot of broken or prematurely worn tools , or parts flying through the machine window
there is good reason why good rigid machines are being manufactured with high rpm spindles , it s not only for aluminum or plastic anymore especially with the quality of tooling hitting the market these days

[tobyaxis]

Why not increase your depth of cut and lower your feedrate. Everyone talks about high speed machining as moving the tool around real fast, how about high metal removal machining if you cut 1mm deep at 8000mm/min you could achieve the same cycle time with 2mm deep at 4000mm/min and have twice the tool life. or 4mm deep and 2000mm/min just use insertable carbide and an air blast.
Joe

Joe,

Application must be considered too. If your machining Thin Walled Parts your D.O.C is going to be Low as well as Feeds and Speeds. I'm talking about walls that are .05 Thick 4 to even 5 inches tall. HSM is the way to go with leaving .05 on the walls for Finishing in steps with the final spring pass of .005 on the side or less.

I have a part on my desk that has .025 walls that are 1.0 inches in height Side by Side at .3 by .3. This was done at EastTech 4 years ago. A friend went because I couldn't go. This part was done with a 1/8 Dia. End Mill 4 Flute Carbide at 60,000 RPM and 120 IPM in .125 DOC. The Surface Finish is like a Mirror and the Precision Down Right Scary .0005. FAST!!!!! Cycle Time .75 Minutes I think, can't remember.

Speed and Precision is the New Game in Machining. We have to stay Competitive with Over Seas Markets.

[joecnc1234]

I want to see an 1/8" em hanging out 1" cutting 1/8 deep per pass at 120ipm and leaving a 32 finish while cutting I'm assuming full cutter dia. sounds a little like a trade show. All I was saying is use what you got if you only have 4000 rpm and no coolant use an air blast and more doc. I've seen so many yahoo machine salesmen tell me about hsm. If you want to spend the money needed for anything over 15000 rpm (+tooling) go for it. as far as dertsap says " with a greater depth of cut the speed and feed are both lower , depth of cut ,work engagement , and proper tooling has the most affect on the efficiency of a cutter ,also greatly affects the the amount of pressure on the tool which can lead to tool failure" This is total BS, speeds and feeds are a set standard. Depth of cut is Dependant on horsepower and rigidity of your set-up if you have the hp and rigidity you can either a) wear out the first .05" or your tool than replace it or b) wear out the first .500 or you tool and replace it, how many more parts are you going to get from b than a???? Talk about cost reduction and production increase how much time does it take for your operator to change out tools, oh no its your set-up guy changing out tools leaving his set-up to help out an operator. This is a subject that I personally have very much experience on and passion about so if you have anything to throw at me bring it.
Joe

[joecnc1234]

And another thing as far as thin walled machining goes I machine airplane parts all day, no walls are thicker than .09" machine inside out or against the stock. It's all about process control and improvement. from a blackbelt.
Joe

[dertsap]

you obviously know what you know

besides anyone on my floor who can t change a simple endmill within a few minutes will be fired out the door

[tobyaxis]

And another thing as far as thin walled machining goes I machine airplane parts all day, no walls are thicker than .09" machine inside out or against the stock. It's all about process control and improvement. from a blackbelt.
Joe

you obviously know what you know

besides anyone on my floor who can t change a simple endmill within a few minutes will be fired out the door

I was a tool show Joe. Take it easy, no one is telling you that you don't know what your doing. Just throwing some stuff out there LOL.

Dertsap most of these so called SetUp guys don't even know that your not supposed to crank the Set Screw with a Breaker Bar LOL. I laugh when I see these guys fighting with a holder because the set Screw Cracked from Over Tightening. Then they never learn from their mistake LOL. We should record this stuff and make a buck or two LOL

[joecnc1234]

Toby,
imagine how much respect you would get if you cut a cycle time in half or 1/3 by using high volume machining techniques. very easy to understand and apply. try it, you will like it. If you don't understand I will help you.
Joe

[tobyaxis]

Toby,
imagine how much respect you would get if you cut a cycle time in half or 1/3 by using high volume machining techniques. very easy to understand and apply. try it, you will like it. If you don't understand I will help you.
Joe

Joe,

I do it every time there is an opportunity to do so. The problem is Convincing the StupidVisor that it is more practical. I sometimes wonder if being Stupid and Arrogant is a Prerequisite for being a StupidVisor.

I know lots of Supervisors that are Great but these other guys don't know $#!^ about applications and production. Go figure they are younger than me and started at the top LOL.

Joe I'm sure I can learn a lot from you. I sent you a PM