Issues with Flex xc3401vrg

[AgustinCano]

Hello! my name is Agustín, Im writing from Argentina. I have problems with my Flex xc3401vrg. When I turn it on, it makes a strange noise, like two pieces of metal scraping. Its a machine from 2015 but its has little use. I attach a video so you can see.
Regards from Argentina!

Agustin Cano Peretti

[video]https://photos.app.goo.gl/PefxsppQy4t6zx4M7[/video]

 

[Mike PhillipsMike Phillips is verified member.]

Sounds kind of normal to me.


Here's something to look for - the bolt and washer that hold the backing plate on. Because you bought this used - you have know idea if previous owners did stupid stuff.


The LENGTH of the bolt that hold the backing plate on needs to be EXACT.

Why?

Because if it's too long there will be a GAP between where the teeth for the inner and outer gears mesh and this will cause NOISE and also possibly tear-up or grind the teeth away so the tool won't work.

If the bolt is too short - there will not be enough threads to correctly hold the backing plate to the spindle.


Here are the correct dimensions for the FACTORY bolt from my how-to book, How to use the FLEX XC 3401 VRG page 7


Factory Bold Size: M8 - 1.25 x 12mm

Factory Washer size: 15/16" or 24mm


I would remove the backing plate and inspect the bolt and washer. I would also inspect, clean and then lubricate the felt ring. LOOK for wear on the underside of the backing plate.

 

[Mike PhillipsMike Phillips is verified member.]

Lubricating the Felt Ring on the Flex 3401


First there is no official recommendation from Flex on this procedure but most owners of the Flex 3401 like to lubricate the Felt Ring to ensure there are no issues between it and the hard plastic backing material that it comes into contact with during operation.

For preventative maintenance reasons, it's okay to lubricate the felt ring after purchase and periodically depending upon how much use your Flex 3401 sees.

What to use?I went to NAPA and purchased some Air Tool Lubricant, (see picture), but any light machine oil should work including the traditional 3-in-1 Oil.


Here's the felt ring on the Flex 3401

Here I've placed some oil on my finger ...

and then spread it onto the felt ring...

You can see the oil penetrate into the felt to lubricate it and from here it will migrate through the felt...

You could also place some drops around the felt ring and then spread it and work it in using your finger...

This brand new Flex 3401 is ready to go to work for a new project next week...

 

[AgustinCano]

Thank you very much, I will try to lubricate the felt ring.

ps: i bought the machine brand new, in 2015, and never replace any parts

 

[AgustinCano]

Here you have another video so you can hear better
[video]https://photos.app.goo.gl/6Dx1wJFVVUURARyG6[/video]

 

[Mike PhillipsMike Phillips is verified member.]

Here you have another video so you can hear better

I don't hear anything wrong.

No tools are whisper quiet.

For what it's worth - you're supposed to use the tool with a pad on it and the pad against the paint. Not holding it in the air.


Lubricate the felt ring, tighten the washer and bolt down and start buffing out cars.


:buffing:

 

[2black1s]

I agree with Mike that your tool sounds pretty normal in the first video. But I do hear some sort of squeal in the second video.

I would disassemble the drive unit to the point necessary to inspect for any scoring/scuffing that might be going on with the bearing surfaces and gear teeth. I beleive that is simply removing the backing plate on the Flex. I don't have one so I'm only going by pictures I've seen of the unit.

By doing that you could also run the polisher with the drive unit disassembled to see if the squeal goes away. This may help you isolate the origin of the squeal.