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Meticulous-Detail
12-09-2011, 09:35 AM
My question is what safe speed setting on the PC should you work with on the PC 7424XP for small work areas using 3 or 4 inch pads? Concerned about heat build up with a small diameter pad and burning the clear coat.

I have used the Adams focus pads with my drill to remove small isolated scratches but never used the PC 7424XP.

BobbyG
12-09-2011, 09:46 AM
I use my 4" foam pads much like the 5 1/2" pads with the appropriate backing plate and speeds 4 to 5 on my Porter Cable 7424.

Since the Porter Cable 7424 polisher is dual action I'm not concerned about burning paint. I follow the same principals and keep the pad rotating and the machine moving...

You can see them in the drawer.

http://i153.photobucket.com/albums/s225/BobbyG53/Detailing/Collection_RD10.jpg

SonOfOC
12-09-2011, 10:42 AM
As Bobby stated, speed 4-5 is ideal. Common mistake is working on a too large of an area. The PC will heat up and the pad can delaminate or collapse in the center. Keep the pad clean and working area smaller than 2ft. x 2ft.

Jumbosrule
12-09-2011, 10:52 AM
As Bobby stated, speed 4-5 is ideal. Common mistake is working on a too large of an area. The PC will heat up and the pad can delaminate or collapse in the center. Keep the pad clean and working area smaller than 2ft. x 2ft.

I actually had this happen, except the backing plate delaminated from the velcro. I was using 7.5" pads on a 6" backing plate, but was doing an SUV with a lot of surface area. What is the solution in this case - give the PC a chance to cool down between panels?

Never ever worried about burning the paint with the PC. I've tried to discover the limits of what the PC is capable of - from smaller agressive cutting pads to heavy cut polishes, they have always been pretty easy to use. Only recently have I decided to go from 5" pads to even smaller pads - like you are talking about. Own them but have not yet tried them.

SonOfOC
12-09-2011, 11:12 AM
7.5" pad on a PC is a little too large for a PC. As the pads gets saturated, the torque required to spin the pads increases, and the PC will really get hot. The heat travels down the spindle to the BP, velcro, and pad.

Staying with a 2ft x 2ft area will give the PC some time to cool down as you wipe and inspect your work. Furthermore, changing pad/cleaning pad will also give the PC some cool down time.

Meticulous-Detail
12-09-2011, 11:25 AM
I had an instance where I slightly damaged the clear coat on a vehicle, attempting to remove an isolated 4 inch scratch. I worked my way up to a green 4 inch pad (Adams) with M105 when it happened on speed 5 with my PC.

Never had this happen before when using my drill and have been successful with my method in the past. This is why I asked the question about the speed setting. The pad was clean and misted with detail spray, I probably applied to much pressure because I kept the PC moving. It was in a tough spot on the fender near a lip.

Jumbosrule
12-09-2011, 11:36 AM
7.5" pad on a PC is a little too large for a PC. As the pads gets saturated, the torque required to spin the pads increases, and the PC will really get hot. The heat travels down the spindle to the BP, velcro, and pad.

Staying with a 2ft x 2ft area will give the PC some time to cool down as you wipe and inspect your work. Furthermore, changing pad/cleaning pad will also give the PC some cool down time.

My experience agrees with you! I noticed the larger pads stressed out the PC. When I bought the starter kit, pad size was not recommended. I had just guessed. As a result, the performance of the pad was reduced after a short use (and the PC got hot). They work just fine for shorter periods. It's the saturation you speak of that requires a cleaning or a new pad to keep up performance. Now they have their place in my kit for final polishes, glazes and sealants, where essentially no pressure is really needed and the product goes on thin to begin with.

shoeless89
12-09-2011, 11:53 AM
As Bobby stated, speed 4-5 is ideal. Common mistake is working on a too large of an area. The PC will heat up and the pad can delaminate or collapse in the center. Keep the pad clean and working area smaller than 2ft. x 2ft.

I learned the heat build up in the pad the hard way once . . .

Rsurfer
12-09-2011, 01:07 PM
My question is what safe speed setting on the PC should you work with on the PC 7424XP for small work areas using 3 or 4 inch pads? Concerned about heat build up with a small diameter pad and burning the clear coat.

I have used the Adams focus pads with my drill to remove small isolated scratches but never used the PC 7424XP.
Using a drill with the smaller pads could cause burning. Stick with the pc to be safe.