Any Okuma LS 20"/21" owners out there with the 7.5hp or 5hp motor?

I recently bought an Okuma LS 20" with the 10hp motor. I am going to switch to a VFD and a new motor, I want to go smaller due to power availability. I can't decide between the 7.5hp or the 5hp. I figure 90% of what I will do is Alum. I could ramp up to save the initial power draw and add a brake...this would make 7.5hp possible.

I have a 55amp panel to my garage for tools, but if my air compressor kicks on, or if the mill is running, that could steal 10-18a, so 30a is a safe number.

If I ramp up a 7.5hp motor, or take deep cuts on Alum using a 7.5hp/5hp motor, what kind of current is realistic? I will be adding a brake, so I am not worried about deceleration.

for the 5hp users, have you had any issues taking deep cuts in Aluminum?

Thanks!

Why not just leave it the 10? I have a 10 horse single phase on a monarch that we have to be takeing .200 a side spinning fast on large material to trip a 30 amp breaker. For the 10 horse the breaker should be a 50 amp. What im saying is i doubt you will ever in normal use, use even 30 amps

10HP on a 20" lathe sounds anemic to me. Would be a shame to have a nice machine and handicap it with not enough HP.

I have the factory 7.5 hp motor on a 24" Ikegai lathe, it's got a built-in manual star/delta switch for startup and runs happily off a 40a 3-phase breaker (the main lathe panel is labeled as 36A draw). Trying to start it in delta pops the breaker.

The load meter's dead so I don't have numbers on cutting load, but overall I've run out of rigidity in workholding and toolholding before I've run out of grunt.

I'd second the recommendation not to go down to 5hp if you can avoid it - aluminum means high speeds, which means losing out on mechanical advantage through gearing.

Last two cents from recent experience: it's nice if the brake system doesn't depend on the same circuit as the motor, so there's a way to slow things down if you lose power at speed.

Why not try it first.....the star/delta start will likely be fine.....wait till there is a problem before starting to change things out...
Make all the connections with oversized wire and try it, you might just be surprised.
Cheers Ross