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

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



The Compression Washer
5inchbackingpatesonDAPs013.jpg



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
DamagedCounterweight01.jpg



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.
DamagedCounterweight02.jpg




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.
5inchbackingpatesonDAPs012.jpg


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
FreeRotatingSpingleAssembley004.jpg




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.
5_0BackingPlates06.jpg




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:
 
Re: Don't use your polisher without it!

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?
 
Re: Don't use your polisher without it!

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?
 
Re: Don't use your polisher without it!

01GMC said:
Simple question, I might have missed it.

What would one recommend if you lost the compression washer?
Click to expand...

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



01GMC said:
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?
Click to expand...

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!


:xyxthumbs:
 
Re: Don't use your polisher without it!

BobbyG said:
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?
Click to expand...

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

Good question though...

:)
 
Re: Don't use your polisher without it!

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!
 
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 ?
 
Re: Don't use your polisher without it!

BobbyG said:
Mike,

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

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


BobbyG said:
What are the dimensions of the washers you use, specifically thickness?
Click to expand...


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.
CompressionWasher001.jpg






:)
 
Re: Don't use your polisher without it!

weijang88 said:
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!
Click to expand...

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.



Ryan R said:
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 ?
Click to expand...

No.

You only need to use one compression washer.


Great questions!


:dblthumb2:
 
Re: Don't use your polisher without it!

Mike.Phillips@Autogeek said:
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.
CompressionWasher001.jpg






:)
Click to expand...

Thanks Mike!! :props: :props:
 
Re: Don't use your polisher without it!

plus, it is next to impossible to remove the backing plate without the wash there.

i was using my PC a few weeks ago and was switching from 5" backing to the 3.5" backing plate, and the washer must have slipped off the 3.5" in the rush of changing them out. i tightened it up and realized something was wrong with the spinning(or lack of spinning) of the pad(before i turned the machine on thank goodness).

I looked and there was the washer sitting on the utility cart! I thought "OH CRAP!!!" i struggled and struggle taking the backing plate off, but finally was able to without damaging the machine. once i got my blood pressure back to normal and reinstalled the backing plate with the washer, i went back to work! =)

like Mike said, treat that little washer like gold!
 
Re: Don't use your polisher without it!

I'm going to go find a rubber gold colored washer!!!! lol
 
Re: Don't use your polisher without it!

This is probably the reason the BP that came with MF kit made weird noise when it was spinning. The rivets was hitting the counterweight, so I switched back to my old backing plate. I think I threw out the washer, because I had never had to use one before. Thanks Mike for the tip, going have to check out HD to see if I can get another one.
 
Re: Don't use your polisher without it!

slickooz said:
This is probably the reason the BP that came with MF kit made weird noise when it was spinning. The rivets was hitting the counterweight, so I switched back to my old backing plate. I think I threw out the washer, because I had never had to use one before.
Click to expand...

My ears pick up on any abnormal sound coming out of DA Polishers when we have classes or project cars.

Often times someone new to machine polishing will change out a backing plate and be unaware of the compression washer and then when they turn the polisher on they'll tend to start buffing because they're not aware of the new, extra noise but my ears pick right up on it.

Kind of like when I use to go to the lake with my drag boat, anytime another drag boat would fire up I would pick right up on it and start scouting the lake for my next race. :D


slicks said:
Thanks Mike for the tip, going have to check out HD to see if I can get another one.
Click to expand...

No problemo... lately I've been making sure that the things I know and take for granted might be of help to others so when topics discovered I try to share on the forum.


:xyxthumbs:
 
Re: Don't use your polisher without it!

Sorry to kick up the dust on an older thread -- I found that my PC came with a washer, as well as my 5.5 inch backing plate. I figure that I shouldn't install both of them so was curious which one is recommended?
 
Re: Don't use your polisher without it!

eatnosenuggets said:
Sorry to kick up the dust on an older thread -- I found that my PC came with a washer, as well as my 5.5 inch backing plate. I figure that I shouldn't install both of them so was curious which one is recommended?
Click to expand...

I don't think you'll find any scientific comparison tests performed to prove one is better than the other, the important thing is to have one in place when using the tool.

Use the one that looks less crushed and save the other in case you wear out the other one or lose it.


:xyxthumbs:
 
Re: Don't use your polisher without it!

eatnosenuggets said:
Sorry to kick up the dust on an older thread -- I found that my PC came with a washer, as well as my 5.5 inch backing plate. I figure that I shouldn't install both of them so was curious which one is recommended?
Click to expand...


Just to note, if you look at these pictues you can see both types do crush, or compress...



Nylon Compression Washer
Here you can see where after tightening the compression washer has an imprint from where it was crushed during tightening.
CompressionWasher007.jpg



Fiber Compression Washer
Here you can see where after tightening the compression washer has an imprint from where it was crushed during tightening.
CompressionWasher008.jpg


:buffing:
 
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