Quote:
Originally Posted by rousher99  i am having alot of trouble using a rotary on the sides of cars. it seems that the pad wants to dig into the car. but i didnt know if there was a tecnique for the vertical panels. i always am sure i have plentyof product and the pad is primed |
Morning,
Let's start from the beginning with why rotary pads bounce at times...my comments are from personal experience from over the years of using a rotary polisher.
Foam buffing pads have a certain density to them. As the pad is rotated over paint's surface with the rotary, the pad will change shape due to downward pressure, speed/rpm, foam density, and the pad's saturation. At the same time, the pad is fighting to regain its natural shape. What do we do? Naturally as the pad begins to lift, move around or bounces we tend to push even harder which usually aggravates the problem even more.
There are a few reasons why pads hop:
1. Not enough product
2. Too much product
3. Your body not being square to the surface
4. Residue from previous step not fully removed
5. Contaminants on the surface causing the compound to grab and thereby gum up.
Having too much product is just as bad as not having enough product. Too much product often leads to a saturated pad, thereby loosing the effective cut of the foam pad. Moreover, as the pad becomes saturated, it begins to lose its ability to go back to its natural shape. Hence the pad will often distort, causing the foam pad to grab even more. If you think about, the DA polisher causes the product to go from the outside edge of the pad towards the middle, but the rotaries direct drive causes the product to be forced to the edges causing the pad to distort as the pad becomes heavily saturated. The higher the speed the more this problem become apparent.
The solution: Change out to clean fresh pads way more often and use a slower speed of around 1200 rpm.
Not enough product also causes issues. The foam pad's density will cause the pad to grab if there is not enough lubrication from the product. Hence, many people including me, prime the pad thoroughly before using. This allows the pad to buff smoothly over the surface. This is also why foam cutting pads tend to grab way more than a foam finishing pad. Obviously, there is the foam cell structure etc involved, but regradless, a dry pad is bouncing pad.
Now with the sides of vehicles, there is another element being added to the mix, the angle of buffing. On the hood or another horizontal panel, most people can adjust the downward pressure easily, making the buffing process smoother (as long as the pads are not over or under saturated with product). But on the sides, one tends to push harder to keep the buffer against the paint as unlike the horizontal surfaces, gravity is not helping.
Solution: The best thing to do is to square yourself to the panel you are buffing. In other words, if buffing on the door, rather than reaching down having your arms out-stretched which causes an unnatural angle and a leverage point, by sitting down on the ground, squaring yourself to the panel, you will be able to control the rotary much better. Lower panels, may require laying on the ground polishing upwards against the panel. If you stand up and buff at a downward angle, your out-stretched arms become fatigued quickly. Then as the buffer starts to bounce, you apply even more pressure and the hop will get worse and worse.
Finally, before each buffing step, wipe down the panel thoroughly to make sure all previous buffing residue is removed before proceeding to the next step. Otherwise, while the old adage "like dissolves like" is often true, two different products mixing may cause the product to gum up leading to certain buffer hop.
Again, this is just from my experience. But I hope it helps!!
Tim
Linear Mode
