feed and speed on mold base pockets

[Jody]

What do you run your finish cutters at when finishing a mold base?

 

I get so mad the base guy slows my feeds and speeds down. I program to ruff the pocket +.015 then I program to finish the pocket with cutter comp so he can cut it closer with a crappier end mill then go and finish it with a good one. We use TIALN coated carbide and he runs a 3/4 end mill finishing a through pocket 1 3/8 thick at 625 RPM and 10 IPM. The finish looks like $hit.

 

We are running our year old haas VM3 like our 20 year old hurco that the haas replaced. At least that is what I feel.

 

thanks for listening to me complaining.

 

Jody

[mig]

When i finishing pocket i using 700 rpm and 13 ipm . Wall of pocket not must be shiny at all.

You must see scalops on the wall. It better for insert to feat in.

Regards

[Jimmy Wakeford from Barefoot CNC]

I think tilan coating hardens at around 750 degrees. If you are not spinnin fast enough your just smearing the coating off and ruining your high dollar tool. I start feed speed calcs from the limiting factor which is usually spindle speed. From there figure your feed. (note some older machines will loose tolerance or start rounding at 50ipm.)

 

I would get this guy some high speed steel tools they are alot cheaper, and will do better at lower rpms.

 

The best thing to do is to get your tool supplier in to do a short (30min) class on tooling and recommend speeds feeds for certain cut conditions. Most are very willing to do this.

[robk]

Jody, try using uncoated carbide for both semifinish and finish. We tried coatings in the past with unsatisfactory results. We leave about .002 with the semifinisher, and than let her rip going 1700 RPM @ 25 ipm (.0037 FPT @ 334 SFM) with a .750 end mill having 4 flutes and using RoyAlloy® 400 series stainless from EDRO. The finish is like glass. We scuff it with 220 grit to make it a little dull... A couple of things you need to consider... Relieve your corners so you don't burry the cutter. Make sure you tram in the cutters within .0005 or better, and it is very critical to break them in for a few seconds. Chip evecuation is pretty important (we use horizontals, so it is not much of an issue). Good luck.

[robk]

quote:

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You must see scalops on the wall. It better for insert to feat in.

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Can you explain this to me mig ???

[g huns]

I'd try Rob's way, they cut some of the best MB pockets you're ever gonna see. Or you could just send Bob out there and have him slap the guy around a little.

[robk]

Thanks for the complement Greg.

Much appreciated

[g huns]

No problem, and it's not just you guys send out Christmas goodies either.

[robk]

Whatever it takes Greg to make ourselves look good

Hope you had a great X-Mas

[Jody]

Mig, but I am a little lost also you say the walls not shiny at all, and the scallop thing also confuses me. Could you please explain?

 

Jimmy that is funny that you said about the high speed mills that is exactly what I said to the foremen when I blew up at him before I ask you all.

 

Rob I am going to order some uncoated EM and try what you are saying. Tell Brad Switt I said Hey. oh do you know him? and yes the chocolet was very good I gained 5 lbs and it is your fault thanks.

 

Right now he is running a 1/2 Tialn EM cutting a base pocket at 250 RPM 2 IPM shoot me now!!!

 

Greg if you are going to be online bothering me you should have gone to work and got paid for it.

 

thank you all

 

Jody

[robk]

Brad says "hello" right back. He is also wishing you a Merry Chrismas & a Happy New Year... He asked me to send you his e-mail address. Check your mailbox for that...

[g huns]

I am at work, stop reminding me.

[mig]

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You must see scallops on the wall. It better for insert to feat in.

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Ok, trying to explain.

For finishing pockets We using GARR TiAL coded cutters now (We don't have any another).

Finishing cutter must be run out NO more then .0005" . Also i am clearing corners of pocket with .002-.003" before finishing.

Rough pocket by insert cutter with .005".

Then by finisher i am making semi finish cut, leaving stock .0015-.002"(don’t forget dia of cutter usually smaller aprox. .001 then nom. size).Then check actual size of pocket , making some corrections if need and finishing pocket.

RPM i am using 700 , feed 13. (Take chips out from the cutter )

Wall of the pocket looks nice but not as a mirror. You can see like a scallops about .0002" on the wall.

Best regards