Sounds like you attached the backing plate without the compressoin washer. I have an article on that....
Don't use your polisher without it!
That is... the Compression Washer
If you don't use a compression washer, the rivets on the backing plate attachment base will come into contact with the counterweight assembly on your DA Polisher.
Damage caused by not using the Compression Washer
Damaged and Gouged Metal
The rivets have gouged the metal because the compression washer was left off. Not only does it gouge the metal it will usually make a horrible noise and that should be your first clue to turn the polisher off and inspect for issues.
Treat the compression washer like GOLD. Don't lose it.
Keep the little rubber nut to lock it into place when not using that backing plate. It's probably more likely you'll own more backing plates into the future than less likely.
The Rubber Nut - Keeps the Compression Washer from getting lost and protects the threads when the backing plate is not in use.
I have scads of backing plates in drawer in the studio and it's nice reaching for a backing plate and
having the spacer washer intact with the backing plate.
The Purpose of the Compression Washer
The compression washer performs multiple functions,
Crushable Interface
The compression washer provides a
crushable or
malleable interface between
two pieces of metal that are going to see a lot of
pressure from being tightened together with a wrench
and my guess is a lot of punishment from the operator. I punish all my tools... so it's not a reach to think others are going to punish their's too. Add to the above mix, the violent oscillating action of the tool on the highest speed setting and add to that
t-i-m-e...
By time, I mean putting your polisher to work buffing out a car
section-by-section,
panel-after-panel. As Pros know and
anyone that wants to get the job in a decent amount of time, when you start buffing out a car you have to keep the tool running and buffing on paint. There's no breaks. That's
time of
endured punishment.
Point being is you
want and need the crushable interface between
two pieces of metal on an electric tool capable of running at high OPM's.
Spacer
They also act as an actual
spacer between the arbor or stud seat where there are the raised heads of a type of rivet or brad that anchors the arbor base to the the backing plate and the threaded portion of the
Free Rotating Spindle Bearing Assembly.
Free Rotating Spindle Bearing Assembly
Here you can see a compression washer seated at the base or seat of the 5/16" arbor or stud where it's attached into the backing plate surrounded by the raised heads of the rivets or attachment anchors.
So keep track of both the compression washer and the rubber nut and don't use your DA Polisher, be it a Porter Cable, Meguiar's or Griot's without it.
Compression washers do wear out with use, that is if you remove and replace backing plates often you're going to wear your compression washer out.
Autogeek carries replacements...
Lake Country Compression Washers 5-Pack
:xyxthumbs:
