The 1" pad will spin many more times per minute then a larger pad (spinning creates heat). Combine that with the circular rotation (rotary) and that is a recipe for disaster (heat burns paint/heat also corrects defects).
If you use the 1" pad don't hold the machine in the same spot for more then a few seconds. Touch the panel occasionally and see how hot it is before proceeding.
Someone else can probably explain this better.
Actually it’s the opposite regarding pad speed and diameter - the outer edge of a smaller pad on a rotary is spinning slower than a larger diameter pad with the machine on the same speed setting.
Had to do some googling to find a better explanation than I could do:
https://www.#############.org/guides/calculate-rpm-changing-pads/amp/
(Edit: not sure why it’s getting edited out - the hashtag’d out site is “detailing wi ki” with no space between)
Flash:Just trying to understand your position- are you saying less pad makes for less heat dissipation?
Edit 2: Side note: can totally see keeping tabs on surface temp when doing small rotary work as you’re likely working on sensitive surfaces like bumper covers, mirrors, and pillar trims where you don’t want to cause the paint to lift/burn.
I agree with oneheadlite... A smaller pad is moving at a slower speed than a larger pad at the same RPM. Regardless of pad size, RPM is RPM. The difference in speed is a result of the circumference of the pad.
Example:
- A 1" pad is traveling at 3.14 inches per revolution at its outer edge
- A 2" pad is traveling at 6.28...
- A 3" pad is traveling at 9.42...
- And so on.
From this example, you can see that in a single revolution a 3" pad is moving across the surface at a speed 3x greater than the 1" pad at their respective outer edges.
So, it's not the speed that creates the concerning heat when using a small pad...
It is rather whatever pressure is applied.
Example:
- If you apply 5 lbs. of pressure to the polisher with a 1" pad you end up with a force of 6.4 PSI at the surface
- If you apply 5 lbs. of pressure to the polisher with a 3" pad you end up with a force of 0.7 PSI at the surface
This is because a 3" pad has nearly 10x the area of a 1" pad (1" circle has an area of 0.78 in sq / 3" circle has an area
of 7.06 in sq)
In conclusion, it's not the speed you need to be concerned with when using a smaller pad. It is rather the pressure you apply. The smaller the pad, the less pressure you should apply to the polisher because the resulting force at the surface becomes exponentially higher as the pad size decreases. Additionally, you can actually up the RPMs of the polisher as the pad speed is actually quite low with small diameter pads.
EDIT: You guys already figured it out on the speed while I was doing my calculations and writing this post. But I believe my pressure description is still applicable.
