I dug out an old Porter Cable 330 Type 1 1/4 sheet sander that I had set aside years ago because it just stopped working. At the time the pad stopped vibrating, nothing moved, I smelled burned rubber or plastic, the motor would whine but nothing moved. At the time I was installing residential doors for a part time job, and I did not have the time to fix it, or even entertain the idea of fixing it. When your are in business and on the road like I was, time is money, and I was in the middle of installing a front entry door and I needed another sander, and quick! So I ran down to the Home Depot, picked up another 330 and returned back to the job. When I arrived home that night I pulled the dead soldier sander out of my truck, threw it my cabinet where it sat for about 10 years till now.

I took it apart a few days ago and found that the only problem was a rubber coupling that joins the pad holder to the motor spindle, was sheared in half. So I ordered one from eReplacementParts.com and had it in my hands a week later.

Below is the old dead man,

Since I already had it apart to find the problem, I went ahead and mocked it back together for this topic and took it apart again for the images. Below image we are removing the pad from the base.

Below is the pad, the base and the motor, it was very easy to remove, just 4 Phillips head screws.

A closer look shows the rubber coupling in the counterweight at the base, and the other half of the rubber coupling at the motor end of things. That is not supposed to be like that!

I went ahead and removed the two halves, I was able to get a pair of pliers around the rubber portion at the base plate and loosen it from there, then the top or motor side of the coupler I was able to simply spin off with my fingers. You'll see the old sheared coupler laying above the new coupler.

The new coupler in place below.

I used the appropriate Allen wrench size to spin the counter weight screw while I held the fan in place with a screw driver, just anything to prevent the motor from spinning while I am tightening the counter weight screw down, while turning the counter weight screw you are also turning the coupler back into the motor side of the sander, the threads are both in the same direction, so both the pad base and the motor are coming together as you tighten the screw.

What I did not show was at the beginning of the repair, in order to get the Allen wrench onto the counterweight screw I had to pull off some clear plastic that originally covered the counter weight screw compartment , I believe this is a dust cover of sorts, so I simply replaced it with some clear packing tape.

Next the sanding pad is reinstalled.

And below again is a last shot of the culprit, as long as that was sheared in half, my sander was not going to do anything, the motor was spinning, but nobody was home!

So, if you have a sander that stops vibrating, but the motor seems to be running fine, chances are it's a sheared coupler that transfers the energy of the motor to the pad base.

Hope this may help someone in the future.

 

By the way, eReplacementParts.com was as nice experience, their website is full of parts, easy to find, and for my case it was not expensive, the item arrived standard ground shipping, one week later as promised, and I'd buy again from eReplacementParts any day all day.

My coupler is Part No. 117 below.

I have that exact same sander. When it breaks, I'll know how to fix it- Thanks!

I have that exact same sander. When it breaks, I'll know how to fix it- Thanks!

You bet Lew, I have had a sander in the past that did the exact same thing, and that was over twenty years ago, I think I threw it away not knowing how easy it would have been to actually fix. I am trying to get out of the disposable society mode in our home.

We actually went out and had Macco paint my wife's 2001 Expedition, the motor runs perfect, interior is fine, but the paint was horrible, so Macco made it look new again! We were thinking of stepping up to a later second hand model, but we decided to go with new paint, since the kids are still young, a 10 year old boy amongst them who still spills drinks on the long family road trips, who needs a stressed out wife watching the kids every move in a newer truck on road trips! So new paint it was, and the kids can have their interior how they want it in the back rows. Juice stains and all! Perhaps when the last child is in college, we'll step up to a newer Expedition, if they still make them by then, but for now, old is good, plus we have a ton of great memories in that ol truck, we brought our newborn son home from the hospital in that ol truck, and the road trips, baseball games, softball, concert performances, many memories. Sorry for going on the tangent, but I see neighbors who just go out and buy a new car just because, we are a disposable society though. There would have been a time I would have chucked that sander, but I thought I'd give it a second life.

Right there with you! We kids were raised by my Mom and Grandparents- all of whom lived thru the depression. I fix and/or save everything.

Very nice save John. Great write up and illustration.