4 Inch Pads and High Speed...

[ALLN1WASH]

Whats up fellas? After joining this forum a few months ago I was introduced to the different sized pads and backing plates. Untill now, Ive only used 7" pads with appropiate backing plate and hand buffed the tight areas. Well... Ill be receiving my new 4" pads and 3" backing plate anyday now. My ? is how do i compensate for the smaller pads when it comes to RPM?

Surely buffing @ 3 with 7" pads has gotta be different than buffing @ 3 with 4" pads, jmo..

What do you guys think/know?Feed back please

[Lasthope05]

Borrowing from Kevin Brown, the formula you would follow is this to compensate for different rpms for different pad sizes:


RPM * C = V
where
RPM = Revolutions per minute
C = circumference <- Notice this is 2*π*r
V = velocity

I came up with: 1,800 (rpm) x 18.84 (6 x 3.14) (6" diameter times pi) = 33,912.

So, using the same formula, and a problem of: X(unknown rpm) x 25.12 (8 x 3.14) (8" diameter times pi) = 33,912 (same as the total of the PFW pad). Then, 33,912 / 25.12 = 1,350 rpm. My buffer had a speed-setting of 1,400 rpm available, so I used it. The velocity wasn't exactly the same, but close enough considering I was only guessing the diameter of the pad actually being used.

[Rsurfer]

Whats up fellas? After joining this forum a few months ago I was introduced to the different sized pads and backing plates. Untill now, Ive only used 7" pads with appropiate backing plate and hand buffed the tight areas. Well... Ill be receiving my new 4" pads and 3" backing plate anyday now. My ? is how do i compensate for the smaller pads when it comes to RPM?

Surely buffing @ 3 with 7" pads has gotta be different than buffing @ 3 with 4" pads, jmo..

What do you guys think/know?Feed back pleaseI take it you are using a rotary? The smaller pad will run cooler, but you still need to take some precaution. I still polish at 1500-1800 with the smaller pads, but reduce it to 1100 on plastic bumpers.

[SeaJay's]

Good info and a great question. I'll be getting my new Flex after they are released and it's going to take some time getting use to. This will definitely help me out. So far I've only used a rotory once and I didn't like it (crappy one I picked up at pep boys for $70, feels like a brick of lead it's so heavy). So, I'm excited to get the new Flex.

[BobbyG]

I'm excited to get the new Flex.

SeaJay, which Flex are you getting?

[SeaJay's]

I pre-ordered the FLEX PE14-2-150. The one that is coming out next year.

[BobbyG]

I've been thinking about doing the same but I wonder what the total price will be? When I look at the ordering page the $379.99 is crossed out.

[SeaJay's]

I think it's crossed out because right now it's just the pre-order so you only have to pay $75 right now. Then the rest when it's released...at least that's how I look at it. Maybe someone from AG can pipe in and set us straight!

[Mike Phillips]

Surely buffing @ 3 with 7" pads has gotta be different than buffing @ 3 with 4" pads, jmo..




It will be easier to control the buffer, small pads are easier to manage and control over larger pads.

How fast you generate heat is actually determined by the type of pad and product. A stiff small foam cutting pad and a compound at 1500 RPM under pressure will generate a lot of heat fast so be careful if using this combo.

As for RPM, depends upon what you're trying to do, for correction work I'm in a range of 1000 to 1500, I rarely go past 1500 RPM for anything but old lacquer or gel-coats.

For polishing, from the lowest speed on your polisher to 1500, again it depends upon what you're trying to do.

Practice on the wife's or girlfriend's car...


:)