Actually there is an "ideal" speed but it is expressed in surface
speed, not RPM. Using the quaint inch-foot system (yuk!), for
aluminum it's in the range of 200 to 300 surface feet per minute (SFM)
and for steel 50 to 60 SFM, in each case assuming you are using high
speed steel or cobalt steel drills. You should not use a carbide
drill in a drill press (you'll break the drill bit) so I'll ignore
that option.
SFM = RPM X PI X DIAMETER
so
RPM = SFM / (PI X DIAMETER)
making sure all units are consistent (if you are using surface FEET
don't use diamter in INCHES, convert to feet). (This stuff sure is
easier in metric!)
Best regards,
Rob Housman
A070
> A question for you techy's
>
> I have managed to 'acquire' a bench drill press with adjustable
chuck speed
> from 160 RPM up to 3000 RPM. Adjustment is a bit messy by means of
moving
> belts up and down different pulley sizes so I would like to set it
up at an
> 'ideal' speed to drill aluminium.
>
> What is the ideal chuck speed?
>
> Richard Iddon (533)
>
>
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<info@avnet.co.uk>
>
>
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