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Confused cam is confused?

Sounds like a dear abby subject line...

I make a program. And record the time on the setup sheet. The guys laugh and tell me I'm way off. WTF? Feedrate is damn feedrate? The total length times the feedrate, how hard can that be to calculate? The guys swear they run it 100%. Times are almost twice as long as I record. Someone might say your post needs...blah blah blah, No way. IPM is IPM on any machine. Rapid rates are different, thats all. Mastercam and that haas was within seconds on a 10 minute program.

I demand better!

Reply to
vinny
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Results would vary unless your CAM system knows exactly your machine accelerating and decelerating rates. If you can monitor actual feedrate in corners on your panel display you will notice slowing down.

If you can upload your NC program I can have a go and tell you an estimated time. If that time is close to your CAM estimate then the machine dynamics cause it to slow, if it is close to actual cycle time then you will know CAM is to blame. If you are using Mastercam and your post is right the later is highly unlikely.

DanP

Reply to
DanP

Is your post outputing time or just the time listed in the ON? The time column in the ON is just approx.

-- Bill

Reply to
Bill

Not like you wouldn't do the same if the roles were reversed....

Reply to
brewertr

The OM time is not including rapids. It's also not reading drilling or turning ops yet. I'm told that comes in v7.5 which will be the big release. 7.0 when it's released will be only a fixer (which is good). You can set up the post with actuals including toolchange time and rapids. That's the best way to go if you have someone at work savvy with Postbuilder.

-- Bill

Reply to
Bill

I run a VF2 SS right beside a Mini mill. The VF2 has 1400 IPM rapids and a quick sidemount, the mini does everything slow. I have run the same program on both machines and recorded the cycle times. Based on faster rapids, tool change and accel, decel, the VF2 can outpace the mini frequently by 10% or better on the same code.

I use the same post for both machines, and the VF2 usually beats the estimate, and the mini always falls short.

Long surfacing programs are frequently way off due to accel decel error. And drilling routines with lots of pecks. One program with 512 holes in 3/4" material took probably 5X longer to run than calculated. I guess I need to work on my post...

Reply to
Polymer Man

More than likely your chip load is wrong. The machine isn't able to cut at your programmed feed rates....

Reply to
Pablo

Is your post outputing time or just the time listed in the ON? The time column in the ON is just approx.

-- Bill

Just looking at the time in the op manager. Weird, today.. I was nervous to go to work. made a huge trode, 40 minutes long. I ask "how long is is taking". op say's "about 40 minutes.

So who knows, maybe its dead nutz.

Reply to
vinny

Chip load wouldn't have anything to do with it. I could say run down a line at 1000 ipm and it'll do it. But... The geometry might be holding it back. Maybe it's cutting the feedrates down to go around corners and stuff. I'm guessing thats what you meant. Soon I will start adding in HSM corner gimmics to keep the machine from slowing down around corners.

Reply to
vinny

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