Announcement

Collapse
No announcement yet.

Ever need a small motor cheap?

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • Ever need a small motor cheap?

    From time to time I have needed a smallish single phase motor in the 1/4-1/3 hp range,but something smaller than the usual 56 or even 48 frame motor.The answer was the ubiquitous Chinese water pump,$35 delivered.



    The one to get is the basket type,where the pump section is attached by three stand off which are cast into the motor end bell.Three screws to remove the pump inlet,pop the impeller off and then void the warranty with a grinder and a zip wheel.



    Little cleanup with a flap wheel and presto,a small motor with a 12mm keyed shaft.They claim it's 1/2 hp @ 3400 rpm,which I don't really believe,but they have been sufficient to replace the motor on a planer knife grinder and this one will be the basis of a small radial fin blower.
    I just need one more tool,just one!

  • #2
    Neat.

    Plus: that pump will come in handy for something, too.

    Comment


    • #3
      I not only needed a physically small motor, but I wanted to be able to speed control it. I used the 3 phase motor off of a coolant pump from some machine tool. I had no requirement for a rigid base.

      metalmagpie

      Comment


      • #4
        Aparently an old alternator makes a tidy small motor, there's a YouTube relating to it, or using alternators as motors, never tried but looks ok, 3 phase.
        I have a few scrap pressure washers I was going to cannibalise for motors, they leak from every plastic connector.
        Mark

        Comment


        • #5
          Originally posted by boslab View Post
          Aparently an old alternator makes a tidy small motor, there's a YouTube relating to it, or using alternators as motors, never tried but looks ok, 3 phase.
          I have a few scrap pressure washers I was going to cannibalise for motors, they leak from every plastic connector.
          Mark
          Ha,who knew,this one sounds healthy too

          https://www.youtube.com/watch?v=hghDLkmCcpE
          I just need one more tool,just one!

          Comment


          • #6
            Cheap way to get an "almost C-face" motor. Of course it IS a chinese motor......"as is, where is, with all faults". But could be a reasonable approach, for sure.

            Too bad they are 2 pole motors. They would look OK on a mini-Bridgeport head. But for any sensible belt system you'd need a 1200rpm, or, at worst, a 1750 rpm motor.
            1601

            Keep eye on ball.
            Hashim Khan

            Comment


            • #7
              I repurposed a 1hp pump motor and lawn tractor transaxle when I powered my 3n1 metal shear/bend/roll. It's still running great after 12+ years of pretty heavy use. I didn't bother cutting the pump flange off. I used it for mounting.



              Comment


              • #8
                Originally posted by wierdscience View Post
                From time to time I have needed a smallish single phase motor in the 1/4-1/3 hp range,but something smaller than the usual 56 or even 48 frame motor.The answer was the ubiquitous Chinese water pump,$35 delivered.

                .
                The weak point in these Chinese split-phase motor's are the caps, if it fails, replace with a N.A. made motor run cap.
                Max.

                Comment


                • #9
                  Where did you source that one Wierd, and do you have any experience/opinion regarding reliability?

                  There have been occasions where I could have put a water pump to use, and if they are worth a damn, $35 makes it cheap enough to have on hand.
                  I found a similar unit on amazon for $36, but it appears from the reviews that half of them only lasted a very short time.
                  https://www.amazon.com/Tooluxe-50635-Surface-Agriculture-Nozzle/dp/B00VQF6T6C/ref=sr_1_4?ie=UTF8&qid=1485666524&sr=8-4&keywords=1+2+hp+water+pump

                  Location: North Central Texas

                  Comment


                  • #10
                    in these Chinese split-phase motor's are the caps, if it fails, replace with a N.A. made motor run cap.
                    These caps, in my recent experience, will still be made in China. Specifically,a Kemet motor start cap. (Faston lug fell off the start cap on my old compressor: have too replace.)

                    Cheers
                    Roger

                    Comment


                    • #11
                      I pulled the 2/3 HP motor off of a rusty shallow well jet pump, and I rewound it to a three phase 8 pole motor for nominal 8 VAC. I made a very crude VFD that ran on a 12 VDC battery. I also worked next door to a HVAC place and often found blowers with various small induction motors by the dumpster. I rewound a couple of them for low voltage three phase, but they could have been repurposed for machine tool use. Very often they were hard to turn because of lack of lubrication but they were easily taken apart and cleaned and lubed, good as new. Mostly they were good brand names like GE, Dayton, Baldor, etc. Junk yards that deal in scrap metal are also good places to get motors from pumps, blowers, fans, and such.
                      http://pauleschoen.com/pix/PM08_P76_P54.png
                      Paul , P S Technology, Inc. and MrTibbs
                      USA Maryland 21030

                      Comment


                      • #12
                        Originally posted by PStechPaul View Post
                        I pulled the 2/3 HP motor off of a rusty shallow well jet pump, and I rewound it to a three phase 8 pole motor for nominal 8 VAC. I made a very crude VFD that ran on a 12 VDC battery. I also worked next door to a HVAC place and often found blowers with various small induction motors by the dumpster. I rewound a couple of them for low voltage three phase, but they could have been repurposed for machine tool use. Very often they were hard to turn because of lack of lubrication but they were easily taken apart and cleaned and lubed, good as new. Mostly they were good brand names like GE, Dayton, Baldor, etc. Junk yards that deal in scrap metal are also good places to get motors from pumps, blowers, fans, and such.
                        Hey, a question for you. My R/C airplane, car, quadcopter brushless motors with 3 wires coming out. Are they technically 3 phase ac motors? Never really thought about it, but I wonder if a VFD would drive them? Or Vice versa, the speed controls for them could be used as a small cheap vfd? Granted, it's DC in, but I wonder if the sine waves go negative, making it AC?

                        Comment


                        • #13
                          RC brushless controllers do transform DC into three phase AC but with square wave. They do control the speed but have difficulty in the start/slow speed range. Usually electric bike/scooter motors/controllers, also brushless 3 phase have better control on the low speed range.
                          Helder Ferreira
                          Setubal, Portugal

                          Comment


                          • #14
                            12 mm shaft? Well that's not really common, as usual shaft sizes are 9, 11 and 14 mm in that size category. Means that finding off the shelf legos to attach to it isn't as easy.
                            Amount of experience is in direct proportion to the value of broken equipment.

                            Comment


                            • #15
                              Originally posted by Jaakko Fagerlund View Post
                              12 mm shaft? Well that's not really common, as usual shaft sizes are 9, 11 and 14 mm in that size category. Means that finding off the shelf legos to attach to it isn't as easy.
                              Straight shaft with 12mm bearings?
                              Bearings go 10, 12, and 15mm in size so that could explain.

                              Comment

                              Working...
                              X