Need Help Please!!!! and recommendations for harbor freight 1x30 belt sander

[eddieblade21]

Hi All, i was hoping someone can assist and maybe someone already performed this modification and have some recommendations. I currently build golf clubs and was using a HF 1x30 belt sander, as it runs at 3400 RPM to turn down golf ferrules. I wanted to convert the belt sander into a variable speed belt sander, I like to have an adjustable belt sander that ranges from a RPM of 100 - 3500.
My issue is with so so many motors, i just do not know one to choose. I also do not want to spend more than $100 for a motor, Power transformer and speed controller. I've seen other use sewer machine motors, treadmill motors, Electric scooter again just don't know which combo to use.

And I want to apologize if this was discussed already

Can someone please help me decide on the following
1. DC brush motor 12V or 36V or 48V and recommended watts
2. Power from 110V to 12V/36V/48V
3. DC Motor Speed Controller Switch

Thank you so much in advance
Eddie

 

[Richard Carlstedt]

Ed, your speed range is out of the question, unless you have step pulleys
For example, a 3600 Rpm motor will have a minimum speed of 600 using a inverter type control.
DC motors have a wider range but the controller will be $$
If you can get a treadmill motor and controller (120 V ) form a throw-away source , it will be the best way ,
of buy a second used belt sander for slow speeds
I see lots of treadmills on Craigs list for little dollars
Rich

 

[awake]

I will echo Rich's comment. I made my own 2 x 72" belt sander, using a treadmill motor and its controller board (one of several acquired for free). Different treadmill controller boards are set up in different ways, and some are more proprietary than others ... but most tend to have one of a few common boards, with varying levels of documentation on the internet. For this particular unit, the controller board requires a 10Hz pulse-width-modulated signal to control its speed (yes, only 10Hz - incredibly slow). I had thought I would rig up an Arduino to control it, but found that PWM controllers are available very inexpensively ($10? or less?) from Amazon et al., so I used one of those. Note that 2 x 72 purists will turn up their noses at treadmill motors, preferring VFD controlled 3-phase motors. The latter is likely superior, but very rarely do I run out of oomph with the treadmill motor I am using (nominally rated at an overly optimistic 2.25hp).

 

[eddieblade21]

Hi everyone and happy fathers day to all the fathers out there hope you all enjoy your day.
Thank you everyone for all yiur inputs. What i decided to do was install a sewing machine servo motor, which i can control from 0-3500 RPM
Still work in progress as i dont like the hall effect arm to control it.
I ordered a Hall Effect Potentiometer.

 

[petertha]

Your motor looks similar to one I'm considering from AliExpress for a different purpose. It comes many power level flavors but all with matched variable speed units. Does yours have something similar?

 

[petertha]

Here is another. I think similar motor but different output shaft style & controller.

 

[eddieblade21]

Hi yes that is basically what i purchased on Amazon its a 110V sewing machine servo motor which was 600W motor.
I am eliminating the hall effect lever amd installing a hall effect analog potentiometer. Also building a PVC box to accommodate the control box and potentiometer so it looks more professional.

 

[petertha]

I think I understand now. Yours does not have a variable speed knob integrated in the control box like the 2 examples I showed?
Have you run the motor & if so, does it seem like its up to the task?

 

[ddmckee54]

I put the 750W version if that servo motor/drive on my drill press, and put the speed pot in a 3D printed box, basically the same as eddieblade21 did - except that I found a schematic that used a Run/Stop switch too. I have 2 complaints about my servo motor/drive: first - my RPM display on the servo drive only displays to the nearest 100 RPM, and second while the motor will run at 100 RPM-ish it clearly is not happy about it. You can hear the motor speed up and slow down as it hunts for the speed setpoint. It seems to be quite happy with 300 RPM and above as a minimum speed though.

Don

 

[eddieblade21]

HI All
I pulled the trigger to install the motor, it actually works great from 300 - 4000 RPM, I cant say if the belt is spinning at that RPM cause i don't have a way to read the actually speed of the belt, i am going on what the screen tells me. I eliminated the pedal adapter and installed a 0v-5V hall effect potentiometer. I did enclose all the electronics in a PVC case. I also changed the drive pulley. I painted the box black as you can see it mounted on the back. the control board is enclosed in a PVC box also and mounted out of the way I added a LED light that only turns on when the belt sander power is on. Some will disagree that the cost is just not worth it, but i am very very very happy with the outcome and honestly the sander is very very quiet compared to when you first get it. I also changed the tension spring and both idler and tension pulley. I did modify the locking handle for the tray with a simple knob.
@ddmckee54 yes at 100RPM the motor does hunt as what i read even though the option is there to lower the speed it is best to leave it 300RPM.

 

[petertha]

They might vary by supplier but verbiage I was provided on the unit shown in post #5 said 500 rpm minimum for either the 3000 or 6000 max RPM unit. I have not pulled the trigger so I cannot corroborate. Specs seem to be a bit iffy depending on seller. Some may say 0-3000, or 500-3000 or just 3000...

 

[eddieblade21]

I agree the minimum can be set to what you want under the recommended spec will not benefit for usage but just ti have it set under the spec. Like mentioned under the minimum spec the motor will hunt. I just did not want the motor to start at 300-400 RPM.

Here are the specs for my motor

 

[ddmckee54]

If you look on Ebay, Amazon, and a LOT of other places you'll find that there's only a couple of different types of servo drives and a host of motor sizes for these sewing machine servo motors. The range of motor sizes is enough to explain the different minimum and maximum speeds. The schematic I used for speed control was made by somebody else on a different forum. (Go to Post #7 in my Drill Press Motor Swap thread on this forum for info on how to get to that thread. That post also tells why I can't post the link here.)

He found that the Hall Effect sensor voltage when the motor runs at minimum speed is about 2.4 volts, below this voltage the motor stops. And at maximum speed this voltage was a little over 4 volts, 4.2 volts I think. His design uses a Run/Stop switch, and the full range of the speed pot. When you flip the switch to Stop the servo drive sees less than 2.4 volts from this circuit so it stops the motor. When you flip it back to Run, the drive goes back to whatever motor speed the speed pot is set to.

There's a parameter in the drive that you can adjust to let the motor coast to a stop instead of stopping almost instantly like it will straight out of the box. Those instructions are toward the end of the drill press motor swap thread. On a belt sander this probably isn't that important, but on a drill press or a lathe the chuck spinning open or unscrewing is not a good thing. (OK, it was amusing to watch the first few times, but then reality set in.)