Soild state phase converter has anybody used one on a Bridgeport

I have a static phase converter on my 2 HP Bridgeport. As mentioned above, only get 2/3 of the rated power, so I'm running at 1 1/3 HP instead of 2 HP. However, Series 1's with a step belt drive are 1 HP, so I figure the 1 1/3 is fine.

Bruce
 
In my case both the mill and the lathe have built in speed change controls that would no longer be functional. The lathe, a Sheldon MW-56-P uses a 120 volt gear motor control spindle speeds by opening and closing sheaves on a Worthington AllSpeed drive. There are no change gears except for threading. The mill also changes speeds by using a manual crank handle to open and close a sheave. In both cases the motors run at a constant speed while the sheaves control the spindle speeds.

Here's a link to a similar lathe on eBay:
https://www.ebay.com/itm/Sheldon-EM...307688?hash=item51f694f328:g:zg4AAOSwXYtYxuAt

Note the control panel and tachometer on the headstock. The buttons on the top row of the panel are, Reverse, Forward, and Stop. On the bottom row is a power on light, Slow (spindle speed), and Fast (spindle speed). This panel would have no functionality if a VFD is used. To further complicate things you would have to figure out how to rewire the gear motor or control the spindle speed by changing motor speed.

I chose the simpler route of installing a static phase converter.
 
I have a manual Bridgeport 1-1/2 hp with a static converter that was installed 20 yrs ago. It worked well for about 2 yrs, then it started blowing fuses for some reason. I took the converter back to the vendor and had it checked, but it checked out fine. So I went with the next bigger unit and haven't had any problems since. Yes, it puts out less power. If I were to do it today, I would go with the vfd. Last year I installed a vfd on my 2hp Bridgeport CNC mill, and eliminated the vari-drive using a solid pulley set up for a poly vee belt. It has more power to the spindle than it did originally.
 
I bought a static phase converter and wired it to a 5HP 3 phase motor, added some oil filled capacitors between the manufactured leg and one of the single phase legs and ended up with a cheap rotary converter that runs all the machines in my shop.
 
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