The Compression Washer - Don't use your polisher without it!

[Mike Phillips]

The Compression Washer - Don't use your polisher without it!



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

[01GMC]

Simple question, I might have missed it.

What would one recommend if you lost the compression washer? Beyond a compression washer, would say a "normal" washer be suffice? Or does the washer, (I beleive it's plastic/fiber,etc vs metal), play a important role with vibrations and such?

[BobbyG]

Mike,

I wonder if the spindle breakage we see from time to time is somehow related to "not" using this washer?

What are the dimensions of the washers you use, specifically thickness?

[Mike Phillips]

Simple question, I might have missed it.

What would one recommend if you lost the compression washer?

Like the title states, don't use your polisher. Stop. Drive to your local hardware store and purchase a replacement.

Beyond a compression washer, would say a "normal" washer be suffice? Or does the washer, (I believe it's plastic/fiber,etc vs metal), play a important role with vibrations and such?

Plays an important role.

Don't use a metal washer, you want a washer that will compress or is crushable for all the reasons I actually listed in the article.


Good question!

[Mike Phillips]

Mike,

I wonder if the spindle breakage we see from time to time is somehow related to "not" using this washer?

What are the dimensions of the washers you use, specifically thickness?

Have to get back on you with the answer... leaving early today...

Good question though...

[weijang88]

I was frantically searching for it today thinking that it came with the backing plate and I threw it out... then I looked at the pad the porter cable came with and the washer was on there. I never knew we had to transfer it to other backing plates. Thanks!

[Ryan R]

Correct me if I'm wrong but are you saying to use this washer in conjunction with the washer that comes with the porter cable ?

[Mike Phillips]

Mike,

I wonder if the spindle breakage we see from time to time is somehow related to "not" using this washer?

No idea but not using a compression washer at all or using a steel washer in it's place can't be good.

What are the dimensions of the washers you use, specifically thickness?

I wrote a supplemental thread to this one here,

The Compression Washer


I figured showing the size as compared to something common like a U.S. Quarter would be more helpful than giving the actual measurements because a person can walk into a hardware store, tell the store clerk what you're looking for and then size one up next to a quarter.

Here's a pictures from the above thread,



The common Compression Washer used with popular DA Polishers is about the size of a U.S. Quarter.

[Mike Phillips]

I was frantically searching for it today thinking that it came with the backing plate and I threw it out... then I looked at the pad the porter cable came with and the washer was on there. I never knew we had to transfer it to other backing plates. Thanks!

Sometimes the simplest things get missed out on...

Anytime you purchase a new, dedicated backing plate it should come with its own compression washer.

You can as an option save the one that comes with the single, factory foam buffing pad with the permanently attached backing plate.

Correct me if I'm wrong but are you saying to use this washer in conjunction with the washer that comes with the porter cable ?

No.

You only need to use one compression washer.


Great questions!

[BobbyG]

No idea but not using a compression washer at all or using a steel washer in it's place can't be good.





I wrote a supplemental thread to this one here,

The Compression Washer


I figured showing the size as compared to something common like a U.S. Quarter would be more helpful than giving the actual measurements because a person can walk into a hardware store, tell the store clerk what you're looking for and then size one up next to a quarter.

Here's a pictures from the above thread,



The common Compression Washer used with popular DA Polishers is about the size of a U.S. Quarter.

Thanks Mike!!