I think my mill power feed may be a failure...

[The Artful Bodger]

.... or at least a semi-failure.

I got a nice case made to cover the motor, the worm and wheel, the dog clutch and to mount a couple of controls. Actually, I was rather pleased at how the dog clutch panned out as that is my most complex milling project so far.

But I seem to have messed up somewhat in my choice of speeds as the slowest I can move the table is one inch per minute (a tad less, 24.3mm in fact). This seems fine for fly cutting aluminium but I have a feeling that will be too fast for work on harder metals such as steel?

[macona]

One inch per minute is way slow enough. I never cut that slow.

[Evan]

There will be some situations where that isn't slow enough. In particular, any sort of cutting with very small cutters, 3mm and below, especially solid carbide cutters.

[dp]

Your anti-gloat is meaningless without pictures!

[The Artful Bodger]

Macona, Evan, thanks, it was the small diameter cutters that I was afraid of breaking through feeding too fast and unfortunately my mill does not have a high spindle speed with a maximum of 2800 plus changing the belt speed is a real pain, in fact I have never used the highest speed so I guess I will need to make myself a little stool to reach those dang pullies!

[The Artful Bodger]

Your anti-gloat is meaningless without pictures!

Ouch!..............

[The Artful Bodger]

Your anti-gloat is meaningless without pictures!

Ouch!..............


IMGP9632 by MrJohnHill, on Flickr
General view...




IMGP9631 by MrJohnHill, on Flickr

Cover off showing the dog clutch.






IMGP9629 by MrJohnHill, on Flickr
I took a panel off the mill base and fitted the power supply in here, there is room for further developements.

[The Artful Bodger]

IMGP9628 by MrJohnHill, on Flickr


Shows worm and wheel.



IMGP9627 by MrJohnHill, on Flickr

The cover is back on..

[John Stevenson]

Looks to me like a DC motor ? If so what about fitting some electronic speed control ?

[macona]

Only 2800 on that big of a mill?. That is kind of surprising. If it has a three phase motor you could overspeed it to at least 4200 like most R8 knee mills, they all use the same bearings.

ME Consultant gives me about 4ipm for an 1/8" 3 flute carbide end mill at 2800 RPM. I have found the main thing with little end mills is getting the chips out. That's what causes the most broken end mills for my and why I added a second mist head to my mill.