What could be wrong? Porter Cable Setup Question.

[Feyd]

So I ordered the Porter Cable starter set from Detailed Image a few weeks back.

Porter Cable 7424 + a bunch of pads, etc. Awesome kit, great service BTW



This setup is based around using 6" backing plate and comes with a counter weight to replace the one that ships on the buffer.

So yesterday I go to polish out my trunk and hood and this thing vibrates/shakes like a MOFO.

Now, this is my first time ever trying to do something like this on my own, so perhaps I'm just not used to it + I'm trying to go slow (not too agressive on the polishes, etc) and it took me a good 2 hours to get the paint all polished out on both areas. Since it's an oscillating buffer, I expected a fair amount of vibration, but to me it seems like it's vibrating too much.

By the end of the stint, I could barely make a fist with my left hand (the one holding the secondary handle). I had to turn the speed down to 2.5-3 because anything above it just makes my hand/arm go numb.


So, am I just a wuss?? Or is there something wrong with my counter weight? Mid way through the job I actually took everything apart and reassembled thinking my counter weight was installed improperly, but it doesn't appear to be.



Any help would be appreciated. I have the majoriety of my car left to do and I just don't think my body can take it...

[HeyMoe53]

Nah, you are not a wuss. I'm no expert here, but it is very likely that the counterweight is not in the proper location. I do know that some owners who use smaller pads (3 or 4 inches) use a different size counterweight. Even though I did not take physics in high school, it would be logical that counterweight location would be in important issue.

Your PC shouldn't shake like that. I just did my 128 on speeds 5-6 with my ten-year-old PC and I could still pick up a cold one afterwards ; )

Hopefully, someone who knows more than I will chime in here.

[Feyd]

Yeah I had to pick up a cold one after....


It's not like the PC is bouncing all over the place... it seems to work nice and fluid over the panels, but it just vibrates like crazy. There is NO WAY I could hold on to it with the speed all the way up..




As far as installation goes, there really is only one way it can be installed... No special hardware to speak of, just a couple torx screws to uninstall one weight and put the new one on.

Maybe my weight is out of balance (though it looks to be solid unless it is somehow a bad casting with hollow spots). Or the oscellation gearing (just made that up) in my buffer is out of sync?

[Red Bread]

I have a counter weight for 5" pads and 6" pads, and to be honest, I can't tell a difference, so I just started leaving the 6" weight on there. I never really go below 4.5 on speed with the PC, as there doesn't seem to be any advantage to the slower speeds for polishing, but I think I recall that it actually feels like it vibrates more at slower speeds.

Toss the original weight back on and turn up the speed.

[Envious Eric]

i use the same counterweight no matter what pad I am using...I really dont see a difference, although I have never ever swapped them out...

use with 5" pads

[Greg@DetailedImage]

I would double check the counterweight and backing plate installation to make sure it's tight and flush. However the PC does vibrate quite a bit on speed 6. Keeping it flat also helps but I'm guessing you did that and the vibration is really pretty normal.

One tip I have is to make sure you wash your vehicle with a rubber glove on your hand before hand. This keeps your hand dry and the vibration doesn't feel as bad. For some reason if my hand is damp I always notice it's more sensitive to the vibration. I guess you could also where a thin glove with the buffer to reduce the vibration you feel in your hands. Just make sure you can have a good grip on the buffer.

As always thank you for the purchase and we always are here to listen to your feedback, questions, etc. so don't hesitate to contact us.

[TOGWT]

Counter-weights

There are two different counter-weights, which are clearly marked to indicate use with either the 5-inch, or 6-inch backing pad. Therefore with a 6-inch backing pad for polishing you should use the 6-inch, 0.140 oz. counterweight (PN 699933) (I also feel this counter weight cuts down on vibration whatever size pad is utilized)

The vibrations that are generated at higher speeds when using a 5-inch weight and a 6-inch pad are unacceptable for most people the counterweights are sizes for sanding paper not a foam pad, so most people just use the 6-inch counter weight

Centre the Foam Pad

To centre the foam pad on to the PC backing plate, set it upside down with the Velcro backing plate facing up (this is easier if the side handle is attached). Using the tips of your fingers as spacers against the edges of the backing plate, you can centre it with near perfect results most of the time


Holding the Machine

The Porter Cable does not require a very firm grip or a lot of force to control. A light but firm grip is all that is required, by holding it with a death grip, all the vibration of the machine is being transferred and absorbed by your hands and forearms, which will lead to a ‘tingling’ sensation in your hands and forearm, consequently leading up to carpal tunnel syndrome.

Ensure that the pad is ‘centred’ and that the correct counterweight is in place and securely tightened. If you are using the supplied side handle it can make the vibration worse. Hold the machine at the base (near the cord/speed setting dial) with the right hand with palm up or to the right side, and guide it with the left hand at the top.