[kolias]

I salvaged the motor in the attached picture from a broken miter saw and I would like to use it on a new jig I want to make. The motor data are:

120VAC, 60Hz., 13.5A, 2.5HP Max. 4800 RPM
The Limit Switch: CD45X, 0311P, 20.5A, 2HP 250, 1HP 125VAC

My question: I definitely would like to have variable speed on the motor and I wonder if the “Router Speed Control” shown on the picture and rated 110VAC /15A would do the job. If not are there any other alternatives?

[Al_The_Man]

As it appears to be a Universal motor, that controller should work, or any Triac based unit, in some cases an added advantage is to add a bridge rectifier between triac and motor.
Another alternative if you want/need precise rpm control is the SuperPID, (see the thread here in the forum).
Al.

[kolias]

As it appears to be a Universal motor, that controller should work, or any Triac based unit, in some cases an added advantage is to add a bridge rectifier between triac and motor.
Another alternative if you want/need precise rpm control is the SuperPID, (see the thread here in the forum).
Al.

Thanks Al

Out of curiosity I used the same controller on a King Canada Scroll Saw I have which has a 110VAC motor, 1.5A, 1 Phase, 60Hz, 1725 RPM but the controlled speed was very erratic to the point the saw was stalling. What is the difference between the scroll saw and the Craftsman motor that will make the Craftsman work?

[Al_The_Man]

If the scroll saw was an induction motor that will happen, or was it fitted with brushes the same as the miter saw?
The controller in your OP is for a Universal (brushed) motor.
Al.

[kolias]

That’s ok Al

Reading to find out what a bridge rectifier is I understand it comes in a form like a chip. Can you tell me the specs I need and how to wire it between the triac and motor?

[Al_The_Man]

Something like the MB242 chassis mount should do it, or one with similar rating. the output of the triac controller is N and L, this goes to the AC in terminals and the +- DC out goes to the motor.
Al.

[kolias]

Something like the MB242 chassis mount should do it, or one with similar rating. the output of the triac controller is N and L, this goes to the AC in terminals and the +- DC out goes to the motor.
Al.

The closest to the MB242 I found is shown in the attached pic and it is MB252 25A but they don’t ship to Canada so I will search locally. It also looks expensive at USD12.95 + shipping so I will connect my motor to the router controller to see what I get.

Please let me know if the attached schematic is correct

[Al_The_Man]

There is a KBPC3510 on Amazon Ca for $5.24, free shipping.
I generally use Digikey as they have a fixed shipping charge to Canada for orders under $100,
The diagram looks right.
Al.

[kolias]

I connected the motor WHT to WHT and BLK to BLK and it works but the motor turns the wrong way. Can I reverse the connection? (WHT to BLK and BLK to WHT).

The router speed control adjusts the speed nice but can only go down to about 2000RPM and full speed sounds good. Not that I need to go lower than 2000RPM but I better go with the bridge rectifier out of curiosity to see the difference.

I didn’t find on Amazon.ca the $5.24 you mentioned but on DigiKey they have one for $4.50 + shipping (Digikey #641-1858ND or KBPC3510-G)
https://www.digikey.ca/products/en?keywords=KBPC3510

If the above it’s ok I will order it

[Al_The_Man]

The rectifier would be OK.
Unfortunately the only way to change direction on a Universal motor is change the field leads over with respect to the armature.
They are all wired in series.
It would mean dismantling the motor.
Al.

[kolias]

I will order the Bridge Rectifier from Digikey soon, thanks

The wrong motor rotation is very strange. This motor came from a miter saw I had and it was working perfectly but I broke the fence and decided to scrap the saw but kept the motor. To remove the motor I had to break the aluminum casting which was holding the motor into the arm of the saw and now the motor has part of the casting attached which I dont mind. I can remove that casting if I want but it means I have to remove the front part of the motor.

In the attached picture the blade turns CW and it should be CCW. Do you see any other reason why the rotation is wrong?

[Al_The_Man]

How many wires come out of the motor?
Al.

[kolias]

You can see there are 3 wires and the Grey color wire is about half the size of the other 2. They all go to a limit switch which I marked ON/OFF switch, that was the ON/OFF trigger

The Grey and Red go straight to the Limit Switch and the White had a splice and I connect my White at the end of the splice.

The BLK comes from the limit switch and I connect my BLK to the end

Perhaps I have connected wrong? The BLK and WHT where I connected my extension to power up the motor had part of the original power cord which I removed and connected my extension

[Al_The_Man]

You wouldn't have the blade on backwards by any chance?
Al.

[kolias]

No the blade goes with the label facing you like I show on my previous picture. If I flip the blade with the label behind then the rotation is ok but this is not normal.

Do you know what the small Grey wire does? (The one going from the motor to the limit switch) I feel maybe there is a safety sensor and the blade turn wrong. I tried to get the manual from Craftsman site to see if they have any wiring diagram but using my Model number (137.285320, S/N: RFT44 I get nothing)

BTW I just got the Bridge Rectifier and only has 2 markings on 2 terminals (+ and AC). Pls see the attached and let me know if I’m correct

[Al_The_Man]

On a bridge chassis mount type, the two AC in are diagonal as is the DC + & - .
Al.

[Al_The_Man]

According to the manual the blade is on the wrong way around.
Al.

[kolias]

So the Bridge Rectifier should be wired like the new attached, thanks

Look in the attached picture Al, there is a window in the aluminum casting with a plastic wheel inside which turns as the motor works. I cover it with black tape to see the results but the motor still turns the wrong way. I feel there must be some kind of a safety to make the motor turn backwards

Is it possible to wire the motor without the limit switch?

Perhaps connecting the power to the Red and White cables coming out from the motor?

[Al_The_Man]

The manual clearly shows the blade on opposite to you pic in #11 post.
It also states that ensure the blade is right for CW rotation when looking at the shaft.
Which means you have the blade backwards.
The terminals of the bridge should be marked AC (in, 1 pair diagonal) and one pair out to the motor, DC + and - .
Al.

[Al_The_Man]

Details here for bridge
Al.