4" pads burning and warping

[sberk1012]

I use a PC 7424 XP with a 3.5" backing plate and 4" pads. The backing plate and pads get very hot. In fact, my LC Hydro Tech 4" pads get burnt and warped after minimal usage. The orange cutting pad below is the most extreme example.

You can see the burnt area in the middle of the white velcro. You can also see how warped the pad is on both sides.

This does not happen with my 5.5" pads. It also hasn't happened my 4" buff 'n shine pads.

Is this normal?

http://www.autogeekonline.net/gallery/uploads/72513/pad11.jpghttp://www.autogeekonline.net/gallery/uploads/72513/pad21.jpghttp://www.autogeekonline.net/gallery/uploads/72513/pad3.jpg

[Dr_Pain]

I've collapsed quite a few pads in my days and I will say that I've never had luck with hydrotechs. It did seem worst on the GG6 then on my Flex or Rupes so maybe the backing plate ventilation helps or with pads that may be better with dissipating the heat.

[af90]

What speed are you using?

It should be set slower than for a 5.5" pad.

Usually I'll use a speed 3 with short stints at speed 4. Hydrotechs are quite weak but work great.

[swanicyouth]

No it's not normal. Your running the machine too fast, using too much polish, or using too much pressure. Its likely a combo of the 3. Heat is the cause of foam collapsing.

The majority of the heat (and the heat that damages / melts pads) does not come from the machine as many believe.... It comes from the friction between the pad and the paint. This can be exacerbated by using too much polish - since wet foam will cool slower + retain and conduct heat more than drier foam.

IMHO you shouldn't have to run any machine above speed 5 (~ 75% of MAX) - even for heavy compounding. Polishing should be done at speed 4-4.5 (usually). If your pad isn't spinning well at those speeds - it better to address the issue than to crank up the machine.

Polishing glass is the exception.

[wdmaccord]

I've used the orange and white LC CCS and flat 4" pads on my GG6 with 3.5" LC backing plate and never had that issue. I typically don't run over speed 4.5 to compound and 3.5 to polish using the 4" pads.

[conman1395]

How often are you changing pads?

[RevitalizeAutoSpa]

My first time with 3" pads I collapsed a LC Yellow by running at 6 with FG400 (a warm polish to begin with). Oops.

[sberk1012]

Thanks for the responses. I usually run it at speed 6 with the 4" pads... sometimes at 5. On the trickier surfaces where the body lines change alot (which is where I use the smaller pads to begin with), the pad would stop rotating because it is tough to stay parallel with the surface. For this reason, I would increase the speed to 6 so it wouldn't stop spinning as easily. I'll tone it down a bit, now that I know this is likely the issue.

Also, I have a buff 'n shine 3.5" backing plate. Does it matter that I use this instead of a LC backing plate w/my LC pads? I never would have imagined that it could matter..I just assumed it'd be be okay as long as I used the correct size.

[Mike Phillips]

I use a PC 7424 XP with a 3.5" backing plate and 4" pads.

The backing plate and pads get very hot.

In fact, my LC Hydro Tech 4" pads get burnt and warped after minimal usage.




Hydro-Tech or water tech pads are closed cell and closed cell tends to hold heat in longer and better than open cell.

Even though the words closed cell can conjure up thoughts in one's mind of a type of foam that won't become saturated with liquid that's actually not the case. Water and liquids can and do penetrate into closed cell foam, just not as easily as open cell foam.

Once water and liquids get into closed cell foam, they don't escape or exit as easily as open cell foam.

Herein lies the problem. Moister, be it water of the liquids inside a compound, polish or wax, will build up inside all foam pads but with closed cell pads it will retain heat better and longer and it is the heat plus the abuse that causes a pad to fail.

Abuse with a dual action polisher simply means,


Time
Pressure
Rotating and oscillating action
Chemicals interaction with the adhesives


Don't know if the above helps but that's the skinny on what's taking place as you buff.

I actually cover this in my how-to book in the chapter on foam buffing pads.



:)

[expdetailing]

I had the same issue with 4 inch LC pads. My thought was to just switch pads more often to give each pad a better chance to not get so hot. Understand that, in many cases, these pads must be used at max speed if desired results are going to be achieved. I don't think running them slower is the right answer. Furthermore, you could try a 4" MF instead of foam. They do cut faster.

[g35_coupe]

Have you tried Cyclo pads? I've run them at higher speeds at times and have yet to collapse a pad. GG6 with a LC 3.5" BP set up.

[Garyhw48]

Just a quick question. I have some of these pads, larger size, and a Flex 3401 and use mainly Wolfgang water based products. I detailed a couple of family cars with Meguiars Ultimate Compound and Polish, saving a dollar or two on daily drivers. The WG's are water based and the Meg's are petroleum based. I noticed more deterioration after using the Meg's. Is this an issue or just a coincidence? The other LC pads seem to last longer, hybrid etc. The product description on AG mentions water based but not petroleum based but doesn't say they can't be used with all products.

[Mike Phillips]

Have you tried Cyclo pads?




I believe the Cyclo foam pads are all open cell. See my previous comments in this thread about open versus closed cell.

Cyclo pads are actually very good DA pads for all the Porter Cable style polishers. Note they are thinner than most other pads...


Thin is in....


:xyxthumbs:

[dlc95]

Probably a silly question, but is your compression washer installed?

[sberk1012]

Thanks for the excellent explanation Mike. It seems to me that an open cell foam pad like the cyclo pads would be a better fit for me. I wonder if the buff 'n shine pads are also open cell...which would explain them not warping like the hydro tech pads.

And yes, compression washer installed