Hi Everyone I could really do with some help with some rough milling . ( the finish is not important I have a grinder ....lol )

CNC Machine cincinnati Arrow 500 max spindle speed 6000rpm

Material to be machined S355 structural steel plate 30mm thick

aiming to achieve a slot 38mm wide 18mm deep and approx 370 long with half a radius in it R70 ( kind of horse shoe shaped )

I have all the dimensions correct ( g code etc. ) and the work piece is bolted down very securely but it seems to me that it takes forever to get the material out . I think im right in saying there is about 253 cubic cm and it is taking about 30 minutes or more to get this material out with cuts 1.5mm deep . I have seen cutters on manufacturers websites removing 1000 cubic cm in 1 minute . Now I know that is their claims and they have the latest cutters and best machines but that would take me 2 hours to do the same amount of work .

The other problem is the amount of carbide tips that are being used . The cutter has 2 teeth and they need turning to a new edge after just one pair of these .

The tips used are ( Grade P3500 ) http://www.cutwel.co.uk/milling/indexable-milling/indexable-milling-inserts/lnmx-korloy-rich-mill-rm4-milling-inserts

The cutter being used is 18mm 2 teeth http://www.cutwel.co.uk/milling/indexable-milling/rich-mill-indexable-milling-family/rich-mill-rm4-90-degree-indexable-end-mill-for-lnmxlnex-insertsr4mps-series


The guy who has been doing the programming for me has been absolutely great and has done it all with no manual for the machine or anything . He is not a programmer just a machine operator and I didnt want to annoy him by getting someone to advise on the last piece of the puzzle , which is the correct cutter at the correct speed getting the time down to more like 10 minutes which I don't think is unachievable ,

Please could any one help with this so I can get the time down on this .

Thanks in advance