[barnesy]

I am trying to m/c s/s 304 with a 4mm solid carbide slot drill .5mm deep full dia. of cutter but keep on chipping the corners using approx. 3000 rpm 350m/mm feedrate what can I do to improve this because this is getting expensive

[joecnc1234]

What is m/c? and convert 350m/mm? and slot drill? do you have flood coolant? are you drilling or milling? If your'e milling with a 4mm em how deep do you have to go to finish?
Joe

[barnesy]

I am milling a slot 5 mm deep,yes I have flood coolant,m/c is short for maching,350m/mm should be 350mm/m

[fpworks]

m = min? ...m is shorthand for meters, not minutes ;-)

so, 350mm/min


How many flutes does your endmill have?

[DareBee]

A slot drill has 2 flutes. (UK terminology)
Chipping means you are going too fast.
See this chart for troubleshooting http://www.speedsandfeeds.com/PDF%20...cationtips.pdf
I very strongly recomend coated cutters - TiAin
They will not only outlast 10:1 but SFM can be increased 15 - 20%

[eorourke]

There are two ways to go: Use a specially designed 3 flute solid carbide endmill with a 35 degree helix and a .2mm to a .5mm radius on the corners. run at 200SFM (4865 rpm) and a feed rate of .025mm per tooth. I would take about 1/2 the diameter for depth of cut. I would use TIALN COATING on the endmill and I would use an air blast to evacuate the chips. My customer called with a machining problem and I have to go and help him in some Titanium. So I will end this posting as I don't get paid for this. I do get paid to solve my customers' machining problems.