Single phase AC motor speed control

[BlownCorona]

Cross posting this from the lathe thread where I'd didn't attract any replies but may not have drawn the right eyes. 

I'm probably gonna just buy a speed controller from aliex tonight and hope but if I'm throwing my money away let me know. 

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Question for single phase AC motors. 

I have a 3/4hp single phase motor that i would quite like to be speed controllable via a knob or switch. I see you can get ac speed controllers for fairly cheap but do any of you clued up electrical folk know is they will work and work well? not looking to go single to 3phase and most of the results i get when searching for answers are to do with this. 

what im starting with is a farily sizable wood lathe, and am turning into a very small engineering lathe with the intention of machining soft metals and hopefully hard metals but only small parts. it has a 3" 3 jaw chuck on it to give you an idea on scale. somewhere between a watchmakers lathe and a small automotive lathe, as this that is what i want to use it for. 

do AC motors become easier to stall if you dial them down via the power supply over mechanically? and if so at which point does that become a problem?

It has speed adjustments via belt and pulley changes but the slowest speed is still fast as fuck lol. dad picked it up for $20 cause the guy said the timber kept coming loose (throwing meter long bits of timber out at i assume mach 1 after looking at it) 

i need to aquire a tiny to small cross slide and either buy, or make a tail stock, so suggestions on these also welcome. also keen on a tiny 4 jaw chuck aswell

[mjrstar]

I'm going to generalise here but running an single phase motor at less than ~75% of normal running rpm will run hot asf, and draw heaps of current and produce very little torque, and sometimes lead to capacitors giving up pretty quickly..

 

Best bet in my opinion would be to see if your current motor is 2 pole and if it is find an equivalent sized 4pole motor which will halve run speed.( do you have a photo of the data plate?)

Or can you potentially make a motor pulley diameter change to bring the speed down.

 

/I'm not an electrician..

[BlownCorona]

most of the data plate was worn away but i was able to figure out what most of the stamped in number where by comparing it to my drill press. ill re do that and let you know. 
ultimately im totally fine with just getting a better set of pulleys or adding a jackshaft if the $50 controller isn't actually a good idea. id rather not get the controller and have to buy a new motor aswell. 

my drill press could do with a better set of pulleys as one of them is fucked so maybe i treat the drill to a new set and use the remaining good pulley on a jackshaft