spindle help

[woodguy60]

i own a shopbot cnc with a router i now want to upgrade to a spindle
i know very little about spindles and how they operate i notice on ebay there
is a couple of 7hp spindles. what i need to know if i was to purchase one of these spindles, what else would i need to go with the spindle , where can i find information on this?
the biggest spindle that shopbot offer is a 5hp. would a 7hp be to big.
thanks paul

[ger21]

You need a VFD to drive it, and it may require 3 phase power to run the drive. A 7HP spindle would most likely need 3 phase power. One other thing to consider when buying on Ebay, is that the cost to have a spindle rebuilt can easily exceed $2000-$3000

[TheWoodCrafter]

Gerry is right about the VFD. That could cost $3000. And you will need 3 phase.
But - I really think 7HP will be over kill and way too heavy for the Z to lift and Too heavy for your Y car.
As for rebuilding, I bought a used 3HP package that the owner said was in good shape, tight bearings and was running good the last time he used it.
Well after making a mount, wiring and figuring out how to program the VFD, 30min running and the bearings were shot. I got a quote of $2000 to rebuild.
I did it myself for $30.
I would look for something a little smaller than 7HP and find a package with the VFD. Then plan on replacing the bearings.
And you will still need 3 phase power.

[Chris Baird]

You can run upto a 5hp spindle on single phase with a 10hp VFD.

[DennisCNC]

[QUOTE= 30min running and the bearings were shot. I got a quote of $2000 to rebuild.
I did it myself for $30.[/QUOTE]

Woundering how you got angular contact bearings for $30, if ones with a 30mm bore are around $600 a pair.