# Ridgid EB44242 Oscillating Edge Belt/Spindle Sander



## Everend (Mar 15, 2013)

I have a Ridgid EB44242 Oscillating Edge Belt/Spindle Sander that I have used for years (out of warranty). When I turn the switch on, the motor will hum but the belt / spindle will not turn. If I spin the belt by hand before turning it on, it will sometimes continue to spin, the humming will stop and it will work as designed. I often have to try several times before it spins up and works correctly. Once on it will run for as long as I need it to (maybe 15 min is the longest I've run before stopping it). 

Any idea if this is repairable? If I knew what the problem was and could get the parts I would/could fix it. I did take it apart but didn't see anything obvious (burn marks or sawdust where it doesn't belong). 

I did just send an email to Ridgid customer service but since it is years old (not sure how many but more than the 3 years its under warranty) I would be surprised if they will help beyond pointing me to someone who I can pay to fix it. I expect paying someone to fix it would cost at least 1/2 the cost of a new one so at that point I'm better off selling this one for parts and buying a new one.

If this one does need to be replaced, should I: 

Buy another like it (from what I can find it's the only option in this price range for both tools).
First buy a disk sander.

thanks
Everend


----------



## Nickp (Dec 4, 2012)

You could check here Ridgid EB44241 Parts List and Diagram : eReplacementParts.com for parts but if it's the motor assembly, it appears to be discontinued. Other parts seem to be available.

I have the same sander and also for a long time...if needs replacement, I would buy the same one again...FWIW...

Are you sure none of the drive parts are too tight...like bearing, bushings, etc...? Does the spindle spin freely...? No sawdust underneath it...? Have you removed the belt sander assembly to see if it changes the symptom...?


----------



## kp91 (Sep 10, 2004)

The fact that it runs after you spin it leads me to think it is a starting circuit problem.

I haven't ever looked too far under the hood of mine, is it a brushed motor? the brushes could be bad
Capacitor start motor? The cap could be bad, or the centrifugal switch stuck
Other starting styles could have a relay in them as well.

Most of these problems would be a cheap fix. 

Almost tempted to get inside of it now and have a look.... Maybe I can find a wiring diagram tomorrow


----------



## Cherryville Chuck (Sep 28, 2010)

The one other problem that's possible is one burned out winding. For some reason motors seem to stop on the same one almost every time, at least that's been my experience. Moving it off that winding will get it going but you can usually tell that it isn't quite up to full speed or power when that happens.


----------



## kp91 (Sep 10, 2004)

*Time to test the relay*

Page 29 of the manual shows a relay is used to control the start circuit. The contacts could be burnt, sticking, or the coil shot.

Should be pretty easy and cheap to find a replacement or equivalent.


Relay shows $20 at ereplacement parts if it is shot.

http://www.ereplacementparts.com/relay-p-161651.html


----------



## Everend (Mar 15, 2013)

Nickp said:


> You could check here Ridgid EB44241 Parts List and Diagram : eReplacementParts.com for parts but if it's the motor assembly, it appears to be discontinued. Other parts seem to be available.
> 
> I have the same sander and also for a long time...if needs replacement, I would buy the same one again...FWIW...
> 
> Are you sure none of the drive parts are too tight...like bearing, bushings, etc...? Does the spindle spin freely...? No sawdust underneath it...? Have you removed the belt sander assembly to see if it changes the symptom...?


When it first started happening last year I tore the whole thing down as much as I could, cleaning as I went. Motors are a bit of a black box for me, I understand the basic physics of how they work but I don't know the specific details of individual motors. So my inspection was for looking for burns, dirt, sawdust where it obviously doesn't belong, that kind of thing.




kp91 said:


> Page 29 of the manual shows a relay is used to control the start circuit. The contacts could be burnt, sticking, or the coil shot.


Ohh cool, thanks for figuring that out. I'll google how to test the/a relay next weekend.


----------



## Everend (Mar 15, 2013)

I should also say this has been a progressive problem. Last year it was working fine. Then every once in a while it would stop working. After a few dozen starts it would hum more often than it would start right up. It was in that time that I inspected the unit. It works (or fails to work) the same for spindle and for the belt. I only get to use the tool a few times each month so when I say it started doing this last year, keep in mind that that's probably only about 5-10 running hours ago. Now it never starts right up and it takes several tries before it does start. Last month (last time I tried using it before tonight) it refused to start at all. I tried to get it to start for several minutes before I decided to let it cool down before trying to start again. That was the first time that day I had tried to use it. Once it gets going it seems to work fine. So I like the explanation that it's a bad relay more than I like the explanation of a bad winding. But again, I only know the high school physics level of detail on motors.

thanks!


----------



## Everend (Mar 15, 2013)

I decided to work on it a little more tonight. Who needs to be awake for work tomorrow?  

The relay looks good. I googled testing a relay and watched a video regarding automotive relay. That doesn't seem to apply since there are only three leads on this one, the video I watched showed four leads. I think that may be a different kind of relay because he was talking about low voltage vs high voltage DC. This one is AC and the switch seems to be in line directly from the power cord with no transformer so that's ~120v AC. One from the switch (I think the ground side) and two from the motor. I came back to the computer to look for a wiring diagram and info on how to test a three lead relay.


----------



## Everend (Mar 15, 2013)

I didn't figure out how to test the relay but it looks ok. I put a volt meter on it but since I don't know how its supposed to work I don't know if it tested correctly.
In an attempt to see if a winding was bad, I tried turning it on, when it just hummed loudly I turned it off, spun the motor a few degrees and tried again. I tried this about 20 times (maybe two revolutions) before the top of the motor started smoking. 
I unplugged it and pulled the motor from the housing. I removed the top of the motor and find the nylon string wound with the wire is what was smoking. Other than the coils getting too hot from having volts without spinning, I can't see anything wrong with it.


----------



## gmercer_48083 (Jul 18, 2012)

Everend, Some capacitor start motors use a mechanical centrifical switch (located at the opposite end of the motor) that could be sticking. remove the opposite motor end to see if it has this mechanical switch. if so just lube it to get it working again. there are an extra set of windings in the field that give the armature an extra jolt of magetizem for a millisecond when you turn it on and as the armature begins to spin....the extra voltage is no longer needed and it shuts off, and continues to run on the Run windings. Think of the motor as having both Start and Run windings. Some motors use a capacitor that steps up the voltage to provide the extra jolt for the start windings. This type of motor is called an Induction Motor. The advantage of an Induction motor is the only wear parts are the bearings and it runs using less current than a Universal Motor. A Universal Motor has brushes that energize the armature windings instead of just magnetizum so it generates more wear and heat. The advantage a Universal Motor has is that it has almost full torque when it starts.


----------



## gmercer_48083 (Jul 18, 2012)

everend, After looking at the actual relay in the parts list provided by Nick, you can see contacts. Can you tell if it engages these contacts when you turn it on and off?


----------



## Everend (Mar 15, 2013)

Could you please explain how to test the relay? As you can see in the wiring diagram there are three leads. The two are obviously attached to the coil but I didn't test conductivity between them. I did put the vmeter on the leads while it was plugged in. I was reading 120v across several connections but it was 11:30 last night past when I should have been in bed so I didn't document my tests.

thanks
Everend


----------



## Cherryville Chuck (Sep 28, 2010)

Be careful about leaving power on while it isn't turning. When a motor is running properly under no load condition it's running mostly on voltage. As the armature starts slipping in the magnetic field the amperage starts rising and that will burn components out very quickly.


----------



## tacomamacxtech (Mar 31, 2009)

*Bad Cap?*

Had the same problem with a table saw once. I'd "Rap" the start capacitor on the motor and it would crank right up!


----------



## kp91 (Sep 10, 2004)

Alright, you talked me into it....

I took the relay out of mine and did some tests, because the picture and the drawing aren't that clear.

First, if you remove the relay and shake it, you should hear it click as the plunger moves back and forth.

I will refer to the contact points by the color of the wires connecting them in my picture, but the tests are done with the relay removed from the circuit.

I did the tests 'actuating' the relay by turning it upside down as shown in the pictures.

With Red and White on the Top:

Red to white - closed circuit (<1 ohm)
Red to black - closed circuit (<1 ohm)
White to Black - coil resistance (approx 1 ohm)
With Red and White on the bottom:

Red to white - open circuit (1000k +)
Red to black - open circuit (1000k +)
White to Black - coil resistance (approx 1 ohm)



Hope this helps. 

Doug


----------



## Everend (Mar 15, 2013)

Oh wow thanks Doug!
I'll run the tests tonight!


----------



## CAD-Man (Apr 28, 2013)

Since I have one of these sanders, I thought I would do a little WEB Surfing and see if I could find a replacement motor for you. I found one and it was at a very cheap price of $257.00 That would be $57.01 more then brand new Sander. You might also look on Grizzly.Com, the also carry there own brand of oscillating Belt / Spindle Sander, Model: T27417. It is a little smaller footprint and the spindle is on the opposite side of the table.

CAD-Man


----------



## hilldh (Mar 7, 2009)

Have you checked to see if you in fact do have warranty? My Ridgid Sander has a lifetime warranty on it.


----------



## Everend (Mar 15, 2013)

With Red and White on the Top:
Red to white - closed circuit (<1 ohm) *It reads 000.1 to 000.3 ohm*
Red to black - closed circuit (<1 ohm) *It reads 000.1 to 000.3 ohm*
White to Black - coil resistance (approx 1 ohm) *It reads 000.1 to 000.3 ohm*

With Red and White on the bottom:
Red to white - open circuit (1000k +) *it reads open circuit*
Red to black - open circuit (1000k +) *it reads open circuit*
White to Black - coil resistance (approx 1 ohm) *It reads 000.1 to 000.3 ohm*

so the relay seems to be working freely. I removed the screw holding the relay together and found the contact points inside were charred. I cleaned them up and put the whole machine back together (committing to that being the fix). .... nope that didn't change anything. I pulled the machine apart again and retested the relay. It still read the same as above. I took the relay apart and the points showed char marks again. So clearly that relay is not the problem.

I did notice a plaque on the bottom of the unit saying the relay is gravity sensitive (as demonstrated above) and turning the machine on while not upright will ruin the motor.


----------



## Everend (Mar 15, 2013)

hilldh said:


> Have you checked to see if you in fact do have warranty? My Ridgid Sander has a lifetime warranty on it.


I may take it into the local Home Depot to see if they have a suggestion. I didn't register the product and their website does not have a serial number lookup. so I don't know.

Here is the response from what Ridgid customer service:


> OCT 03, 2016 | 12:38PM EST
> Tom replied:
> Everend
> 
> ...


----------



## Everend (Mar 15, 2013)

tacomamactech said:


> Had the same problem with a table saw once. I'd "Rap" the start capacitor on the motor and it would crank right up!


As far as I can tell there is no capacitor on this motor.


----------



## Everend (Mar 15, 2013)

gmercer_48083 said:


> Everend, Some capacitor start motors use a mechanical centrifical switch (located at the opposite end of the motor) that could be sticking. remove the opposite motor end to see if it has this mechanical switch. if so just lube it to get it working again. there are an extra set of windings in the field that give the armature an extra jolt of magetizem for a millisecond when you turn it on and as the armature begins to spin....the extra voltage is no longer needed and it shuts off, and continues to run on the Run windings. Think of the motor as having both Start and Run windings. Some motors use a capacitor that steps up the voltage to provide the extra jolt for the start windings. This type of motor is called an Induction Motor. The advantage of an Induction motor is the only wear parts are the bearings and it runs using less current than a Universal Motor. A Universal Motor has brushes that energize the armature windings instead of just magnetizum so it generates more wear and heat. The advantage a Universal Motor has is that it has almost full torque when it starts.


I haven't tried pulling the other end of the motor off.... well sort of. The other end has the mechanism that pushes the arm up and down while the motor spins. Its a plastic housing with 'ramps' inside and the bottom of the motor has a spring arm that rides up and down on the ramps as the motor spins causing the oscillation. I did pull the housing off and found it filled with clean grease. Since that whole end is covered in the clean grease inside a sealed space I just put the cap back on and sealed it back up. 

I'll see what they say at the home depot store.


----------



## honesttjohn (Feb 17, 2015)

Unless you have a desire to just see if you can troubleshoot and get it going again for your own satisfaction, I'd just spend the $199 and go get another one. This one has served you well and owes you nothing.

I got one and love it.

HJ


----------

