3-phase woodworking machine question

[Jason White]

I see a lot of used woodworking machines on Craigslist that are 3-phase electric. As such, they seem to sell for less money because there's a smaller pool of people interested in them.

I know you can get a phase converter, but can't you also just swap out the 3-phase motor with a 1-phase motor? Or is there more to it than that?

- Jason

[Myk Rian]

Just swap it out.

[Jason White]

Will the existing power switch work, or will I need to change that, too?

[David Kumm]

When you go to single phase you are doubling the amp draw so depending on the electrics you might need to do nothing or swap out the mag starter, or at least change the heaters. Not a huge deal although I would not change over a three phase motor. Once you get into industrial machines you will get to like them and look for a permanent solution. VFDs, RPCs, or Phase Perfect. Dave

[Keith Bohn]

It depends on the switch (motor control) but typically yes/just use two legs instead of three. If it has heaters there may be some diddling with that.

[Jeff Monson]

When you go to single phase you are doubling the amp draw so depending on the electrics you might need to do nothing or swap out the mag starter, or at least change the heaters. Not a huge deal although I would not change over a three phase motor. Once you get into industrial machines you will get to like them and look for a permanent solution. VFDs, RPCs, or Phase Perfect. Dave

I think that is the best advice, I have 3 different 3 phase machines in my shop now, all run off a RPC which came with my 1st machine purchase. 3 phase is easy to wire also Don't let 3 phase intimidate you, its not a big deal IMO.

[Bruce Page]

I wouldn’t change out the motors. I have two 3phase machines that run off a single Phase-O-Matic converter. I’ve had this setup for over 20 years and never had a problem with it.

[jack forsberg]

Jason

You would think that that all it takes is to switch out the treefaze motor for a singa faze. and in some cases that is the easiest to do if its a light little machines that were offered to the market in single phase options. you know the consumer grades like Delta ,grizs ,powermatic.

here are the issue as i see them. First not like you going to be able the switch out a RAS motor or a direct drive mortiser motor for single phase at a cost that would make it worth it. Two the motor control are general of the more industrial kind and some are not single phase compatible and so you will need a new switch$$$$$$. Three some single motors wont fit into the opening/motor mount because of the start capacitor humped up on the motor gets in the way(three phase motors are generally smaller). forth motor rotation can be a problem as not all single phase motors are reversible and three phase are so machine with forward and reverse can be a challenge.. fifth single phase motor only come in 2 voltages (120/240) where as 3 phase more come in many and you can not use motor starer that are of a different voltage because of sizing in some cases. lastly understand that a single phase motor the same HP will draw more amps than its three phase counter part and this may mean rewiring all the electric in the machines.

If a machine you are looking at is 240 volts and under 3 hp is will cost way less to use a VFD IMO
VFD are so easy to wire a monkey could do it.

Don't be put off to keep a machine 3 phase as it is in more cases a better chose for braking speed control and so many other things.ever wounder why the industry uses 3 phase? And everyone knows real machines are 3 phase.

My opinion is swamping the motor for single phase is the most expensive way to go .

jack
English machines

I see a lot of used woodworking machines on Craigslist that are 3-phase electric. As such, they seem to sell for less money because there's a smaller pool of people interested in them.

I know you can get a phase converter, but can't you also just swap out the 3-phase motor with a 1-phase motor? Or is there more to it than that?

- Jason

[Stephen Cherry]

Three phase machines are like Utz Potato chips, if you have just one, you want them all.

[jack forsberg]

Three phase machines are like Utz Potato chips, if you have just one, you want them all.

And then there are the voltages that are like all the flavors. way be 2 dimensional when you can be 3?


jack
English machines

[Peter Quinn]

Jason

You would think that that all it takes is to switch out the treefaze motor for a singa faze. and in some cases that is the easiest to do if its a light little machines that were offered to the market in single phase options. you know the consumer grades like Delta ,grizs ,powermatic.

here are the issue as i see them. First not like you going to be able the switch out a RAS motor or a direct drive mortiser motor for single phase at a cost that would make it worth it. Two the motor control are general of the more industrial kind and some are not single phase compatible and so you will need a new switch$$$$$$. Three some single motors wont fit into the opening/motor mount because of the start capacitor humped up on the motor gets in the way(three phase motors are generally smaller). forth motor rotation can be a problem as not all single phase motors are reversible and three phase are so machine with forward and reverse can be a challenge.. fifth single phase motor only come in 2 voltages (120/240) where as 3 phase more come in many and you can not use motor starer that are of a different voltage because of sizing in some cases. lastly understand that a single phase motor the same HP will draw more amps than its three phase counter part and this may mean rewiring all the electric in the machines.

If a machine you are looking at is 240 volts and under 3 hp is will cost way less to use a VFD IMO
VFD are so easy to wire a monkey could do it.

Don't be put off to keep a machine 3 phase as it is in more cases a better chose for braking speed control and so many other things.ever wounder why the industry uses 3 phase? And everyone knows real machines are 3 phase.

My opinion is swamping the motor for single phase is the most expensive way to go .

jack
English machines

Uh.....what he said. It's a rare machine where you can find a cheap easy bolt on 220V replacement. If there were only one motor mount in the world things would be easier. Sure you can machine your way out of many situations, but time has an expense too. Three phase motors are always smaller at the same HP rating. No caps, no start windings....just smaller, so single phase motors wont always fit in the given space. A good industrial 3 phs motor could run virtually forever, much simpler than single phase. And often the starter circuit really is wired in a much lighter gauge wire than single phase will require, so you would wind up rewiring the starter, maybe replacing a mag starter too. I found for my shop that once I got a 3 phase circuit running via RPC, three phase machines became much easier to acquire. I got one great deal that made it worth it to get the RPC, not an easy machine to swap motors, the single phase motor was actually going to cost me more to install than doing the phase conversion soup to nuts. So yes, you may find an occasional cheap motor swap situation, and if you have a pile of 220V motors around, or you only want one such machine, go for that. But honestly, once you get used to 3 phase industrial equipment, you want more, and its almost definitely going to be more expensive/difficult to convert a variety of machines. Easier to get one good phase convertor, deal with all 3 phase. I can only run one machine at a time, but its a one man shop, so unless I grow two more hands, thats not a problem.

[Steve Kohn]

I've learned that one huge benefit with 3 phase and a converter is the ability to make any machine variable speed. On some machines this doesn't matter, however on sanders it can really help prevent burning and allow much more control. I recently restored a combination sander that was 3 phase. The variable speed option is the main reason I'm hanging onto it. It is really much more useful for both wood and metal. I'm even considering converting my single phase edge sander over to 3 phase by changing the motor out and putting a converter on it.

[jack forsberg]

here is a simple 3 phase Drill press i got for $95 that cost $130 to convert with a VFD to run on 120 volts single phase house hold power.

tell me if you think i got more than a single phase motor change would have given me?
this video show the VFD upfit.
http://www.youtube.com/watch?v=6UsuoWTe7xs

this its it finished



jack
English machines

[Peter Quinn]

here is a simple 3 phase Drill press i got for $95 that cost $130 to convert with a VFD to run on 120 volts single phase house hold power.

tell me if you think i got more than a single phase motor change would have given me?
this video show the VFD upfit.
http://www.youtube.com/watch?v=6UsuoWTe7xs

this its it finished



jack
English machines

I'm loving that drill press. The foot pedal looks pretty handy, variable speed on the fly is great. To me it actually make more sense to buy single phase machines and replace the motors with 3 phase than the other way around in some cases....such as anywhere variable speed is useful. Kind of gives you a mini bridgeport there. Throw a XY milling table on there and I'm in drill press heaven. Now I'm on the mental lookout for a 3 phase DP!

[Larry Fox]

I agree with other posters have said about NOT changing. My tablesaw is 3-phase and runs off of a large RPC. It did take a while to get all the wiring done as I added a new single phase and 3-phase sub panel but now that I have it, I love it because of the opportunities it presents me for other machines. One thing to keep in mind though is that 3-phase electrical equipment like breakers and panels tend to be more expensive than their single phase counterparts but eBay is rife with listings.