Why is this happening?

[Grizzly]

I was using my PCXP today with a Meguiars W68DA backing plate and a Meguiars W8207 7inch Soft Buff Polishing Pad, I marked the back of my pads with a black sharpie marker to make sure the pad is actually rotating.

The PCXP was on speed 5 and the pad was rotating when no pressure was applied, but when pressure was applied the PC just started to vibrate or jiggle around and not really rotate. But when I went to speed 6 there was not a problem.

Is the pad or backing plate too large for the PCXP to handle?

Does using speed 6 dmage the backing plate or pad?

What exactly is going on here?

[JonMiles]

What happened at lower speeds?

[Grizzly]

First I tried Speed 4 and it rotated the pad under the weight of the machine but when pressure was applied the pad barely rotated, then I tried Speed 5 and when meduim pressure was applied it slightly rotated.

Then I used Speed 6 and it worked great even under pressure. The problem is I have heard the backing plate and pad can get damaged when using Speed 6.

[A4 1.8tqm]

Never used a PC myself (Flex 3401), but as far as I've read even the new PC XP can't handle 6" pads and above. Seems the 5.5" pads are the largest most users will recommend. Just my $0.02 :xyxthumbs:

[Grizzly]

Never used a PC myself (Flex 3401), but as far as I've read even the new PC XP can't handle 6" pads and above. Seems the 5.5" pads are the largest most users will recommend. Just my $0.02 :xyxthumbs:

That does help. I am sure its not the machines fault, but rather mine.

But my Meguiars G110v1 seems to handle it better than the PCXP.


I am really confused. If I have to I will order some LC 5.5" pads, hopefully they will work with my W67DA or W68DA Meguiars backing plates.

[JonMiles]

I had a pc for a while and it seemed to get bogged a little with larger pads, but at speed 4 and 5 it was very unnoticable. I used 6.5's for a while then switched to 5.5's and never had a problem. It might be the same problem I had just to a larger extent. At low speeds it would nearly stop, fell down to like 100 opm's. I would just try some smaller pads and if it doesn't work then you might want to return it and try to get another, every once in a while you get a dud with power tools

[Grizzly]

I had a pc for a while and it seemed to get bogged a little with larger pads, but at speed 4 and 5 it was very unnoticable. I used 6.5's for a while then switched to 5.5's and never had a problem. It might be the same problem I had just to a larger extent. At low speeds it would nearly stop, fell down to like 100 opm's. I would just try some smaller pads and if it doesn't work then you might want to return it and try to get another, every once in a while you get a dud with power tools

Yeah, I am using 7" Meguiars polishing and finishing pads so I imagine it is just getting bogged down.

[Grizzly]

Maybe I should give the stock white pad that comes with it a try, see how it works.

[A4 1.8tqm]

Those DA's have a "safety feature", when the machine is put under too much load the pad will no longer rotate saving you from burning through the paint. With such a large pad it won't take much pressure too stop it. The the larger diameter causes more leverage to be placed against the motors rotation. The further from the center the higher the speed, meaning more load. For a forced rotation machine with a strong motor that can handle the load, further from the center means faster correction (or burn through). :)

[Grizzly]

Those DA's have a "safety feature", when the machine is put under too much load the pad will no longer rotate saving you from burning through the paint. With such a large pad it won't take much pressure too stop it. The the larger diameter causes more leverage to be placed against the motors rotation. The further from the center the higher the speed, meaning more load. For a forced rotation machine with a strong motor that can handle the load, further from the center means faster correction (or burn through). :)

I undertstand about the whole safety clutch thing but I am just trying to pinpoint the problem.

Are the 7"meguiars pads just simply too big and will bog down under pressure and stop the pad from rotating?

[Brennan Beasley]

I had a similar event with the 7" soft buff 2.0's on my G110v2. With the burgundy pad and not to much pressure rotation would stop. Went to 5.5 LC's and works like a charm now.

[Lasthope05]

You might just be using too much pressure. Hundreds of thousands of people on MOL use the 2.0 7" pads without problems and with great success on a the older g110 v1.

I highly doubt a PC XP with more power would have problems of bogging unless excessive pressure is being used.

We all know smaller pads have greater correcting abilities but 6.5"-7" pads have worked and have produced great work for years way before the PC XP, Griots, and G110 came out. So I really dont understand how people can sit back and say larger pads dont do squat and stink.

[JonMiles]

You might just be using too much pressure. Hundreds of thousands of people on MOL use the 2.0 7" pads without problems and with great success on a the older g110 v1.



Dude thats alot of people on MOL :buffing:

[Grizzly]

Just trying to pinpoint the problem here guys. It was weird since when I used Speed 6 there wasnt a problem at all.

I will do some more testing tomorrow.

[tkc]

I had the same problem with my 6.5" pads, especially the orange pad with some megs105, i switched to 5.5" low profile pads and have not had the 1st problem since! Work's great now!

I believe it's the pad size, at least that's what it was with mine... hope it helps!