Haas claims their Mini-Mill has 7.5 horsepower:
http://haasportal.net/Portals/57ad7180-c5e7-49f5-b282-c6475cdb7ee7/DS_MMseries_US_7_2008.pdf
Machining Formulas From Dapra:
http://www.dapra.com/tech/dloads/Dapra-Milling_Formulas.pdf
MRR (Cubic Inches per Minute) IPM x WOC x DOC
Horsepower Consumption = MRR x mf
mf – steel = 1
mf – gray iron = .65
mf – aluminum = .3
I’ve tried taking a cut with our Mini-Mill in 6061 aluminum with a 3 flute carbide .500 end mill, at a .250 depth of cut, full width, using 6,000 RPM.
45 IPM x .5 x .250 = 5.625 MRR
5.625 x .3 = 1.6875 horsepower to make this cut.
Taking this exact cut on our Haas Mini-Mill just about stalls the machine out.
Reducing to a 3,000 RPM spindle speed and the machine will barely make this cut.
Do you think Haas is being anywhere close to honest when they say their Mini-Mill has 7.5 HP?
first.. You really need to work on the layout of your blog.. Figure out a way to organize everything.. It’s a real pain trying to find something.. heh..
As for the haas, its a variable HP machine.. You have 7.5 HP at low RPM, then you loose HP as you ramp it up.. What do you expect from a machine that costs the same as a car?
Comment by tnik — December 12, 2008 @ 12:16 pm
“As for the haas, its a variable HP machine.. You have 7.5 HP at low RPM, then you loose HP as you ramp it up.. What do you expect from a machine that costs the same as a car?”
I expect an realistic horsepower rating. Rating the Haas Mini-Mill at 7.5 HP at 1200 RPM isn’t realistic for how anyone would machine say something like aluminum.
Do you think this is an honest or realistic way to rate the horsepower of a Mini-Mill or for that matter any other machine?
Do you think the owner of Haas has a stellar reputation for being honest?
If more machinists spoke up / blogged about this kind of totally bogus way of rating a CNC machines horsepower do you think Haas would be forced to be more honest in how they rate the horsepower of their machines?
Comment by jonbanquer — December 13, 2008 @ 5:16 am