Milling slots in 1018 CRS

[mattpatt]

Hi,

I have a job milling some slots in 1018 CRS.

Basically a flat plat 10mm thick. One 15mm wide slot, 5mm deep, right through from one edge to the other, so it's open ended.

The only success I've had on the 15mm wide slot is coated carbide 12mm 4F endmill at 0.5mm depth, 2600rpm and 1000mm/min feed. Flood coolant.

G wizard reckons on almost full depth of cut (4.4mm), 2538rpm and 645mm/min feed.

Basically I'm scared to come in a full DOC. I can't afford to scrap this job but it's taking too long.

Should I just go for it?

Flood it or dry with air? or?

Any help much appreciated.

[Karl_T]

The DOC you can take depends on your machine. Mine wouldn't do this. But I'm sure there are many that are plenty rigid.

Karl

[mattpatt]

Doing the job on a Fadal 3016

[robertproff]

I have had a lot of success with using an Hanita VarimillII. Using a 1/2" EM I have taken a 1/2" depth of cut at 3600RPM's and feed of 36IM. Hanita claims a 1.5Xdia depth of cut. This is a 5 flute end mill.

[DareBee]

You should be able to do that easily on the FADAL.
Any standard length endmill is supposed to be able to handle .5Xdia in DOC at full feed rate.
My Starting point would be 2200RPM @ 20IPM with heavy flood (Using the endmill you listed).

[mattpatt]

Thanks for your advice. I kinda knew what you were going to say, so I suppose that I should just get stuck in and stop being so cautious.

One of the coated endmills has just had the bottom face ground, so the coating is no longer there. Should I now consider it as totally uncoated and slow things down a touch?

[DareBee]

No - you are cutting with the flutes, not the end.

[mattpatt]

Thanks for your help guys.......I'm hauling ass now :-)

Regards,

Matt.....no longer scared