Re: [CAD_CAM_EDM_DRO] CNC'ing a Mini Mill

Jon has a way of breaking the bad news to people gently :-)

Just as a point of reference, Bridgeport rates their 4 HP 4J head for
removing 4 Cu. Ins/Min of mild steel. This head is used on their Series II.

At 11:41 PM 11/17/2003 -0600, you wrote:

>jharnedy@... wrote:
>
> >Am converting a Chinese MiniMill circa 250KG, with round column on Z.
> Plan is to convert the X (stroke 405mm) and Y (Stroke 200mm) first. End
> use would be on plastic, wood, al alloy, brass and mild steel. My "max
> cutting conditions" would be 2 flute HSS end mill 25mm dia at 750mm per
> min with a 2mm depth of cut, what would be the load generated?
> >
> >
>You are kidding yourself! I think a Bridgeport Series II would be
>humming VERY loudly
>and maybe dancing across the shop floor at this load. My calculator
>indicates this will
>absorb 4 Hp in mildest steel, and almost a full HP in aluminum. You
>don't indicate
>your RPM for this, so I can't calculate chip load or linear force
>generated, but I'd guess
>it would approach half a ton. I can tell you with absolute certainty
>that I've never gotten
>within 10% of this cutting rate (2.4 In^3 / min) on my Bridgeport.

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