Tachyon
New member
I've used a random orbital (Griot's) polisher for about a year now with OK results. But with 2 hard-coat BMWs in the stable, it takes far too long to work out all the swirls and stuff, plus there always seems to be a tough spot that the RO cannot overcome. So it is time to step up.
I purchased a reconditioned Porter-Cable 7428 7" variable-speed polisher.
I tested it out on a swirl-laden panel (trunk lid of our 2002 BMW 330xi), here's the results.
before
after
I started with Menzerna IP on a Lake Country CCS 8.5" orange pad ... and it did a nice job polishing out the lighter swirls but the heavier stuff remained, even after 2 passes.
So I boosted the cutting power by using Optimum Compound on the orange pad (I don't have a yellow pad yet for the rotary). Much better -- OC rocks! It killed off most of the tough swirls and finished nice and clean ... one pass.
I finished with ZPC (white LC CCS pad) and a hand coat of ZAIO.
First impressions of a rotary:
Quiet. Compared to the racket a RO makes (ear plugs required), this thing is quieter than stirring batter in the kitchen with a mixer.
Heavy: This sucker is hefty! In a good way. At 8 lbs. you can let the machine to all the work. However, this will get interesting when I try it out on a vertical panel ... must keep working out with weights.
Quick: Night and day difference compared to a random orbital. You can get so much more work done in a shorter time. I'd say that instead of 3 passes of 3 minutes each using a RO, you can get the same work done using a rotary in one pass of 2 minutes.
Strong: This ***** has power, and it's very clear that you have to pay full attention at all times or she will bite back. However, I did not find the machine to be unruly. I ran it at a dial setting of 3 (out of 6) and pulled the trigger to about 80%, so I was probably spinning at about 1,200-1,300 rpm max.
I used the pyramid method of laying out the polish at about 600-800 rpm, working it in at 1,200-1,300, and then finishing it off at about 800. This seemed to work well as I didn't get any odd marks.
Controllable: I really like how you can vary the speed so easily with the trigger. This is so useful when you are working a panel near the edges and around curves.
Using a rotary is very different than an orbital, but I would say that I found it easier to use than I expected (I guess I read so much about what can go wrong that I expected something much more difficult). And the benefits are huge: faster work and a better finish.
If you are a hobbyist like me, and are experienced and comfortable using an orbital, the jump to a rotary is not that big of a leap. I'm glad I did it and I look forward to learning more about how to use it.
I purchased a reconditioned Porter-Cable 7428 7" variable-speed polisher.
I tested it out on a swirl-laden panel (trunk lid of our 2002 BMW 330xi), here's the results.
before

after

I started with Menzerna IP on a Lake Country CCS 8.5" orange pad ... and it did a nice job polishing out the lighter swirls but the heavier stuff remained, even after 2 passes.
So I boosted the cutting power by using Optimum Compound on the orange pad (I don't have a yellow pad yet for the rotary). Much better -- OC rocks! It killed off most of the tough swirls and finished nice and clean ... one pass.
I finished with ZPC (white LC CCS pad) and a hand coat of ZAIO.
First impressions of a rotary:
Quiet. Compared to the racket a RO makes (ear plugs required), this thing is quieter than stirring batter in the kitchen with a mixer.
Heavy: This sucker is hefty! In a good way. At 8 lbs. you can let the machine to all the work. However, this will get interesting when I try it out on a vertical panel ... must keep working out with weights.
Quick: Night and day difference compared to a random orbital. You can get so much more work done in a shorter time. I'd say that instead of 3 passes of 3 minutes each using a RO, you can get the same work done using a rotary in one pass of 2 minutes.
Strong: This ***** has power, and it's very clear that you have to pay full attention at all times or she will bite back. However, I did not find the machine to be unruly. I ran it at a dial setting of 3 (out of 6) and pulled the trigger to about 80%, so I was probably spinning at about 1,200-1,300 rpm max.
I used the pyramid method of laying out the polish at about 600-800 rpm, working it in at 1,200-1,300, and then finishing it off at about 800. This seemed to work well as I didn't get any odd marks.
Controllable: I really like how you can vary the speed so easily with the trigger. This is so useful when you are working a panel near the edges and around curves.
Using a rotary is very different than an orbital, but I would say that I found it easier to use than I expected (I guess I read so much about what can go wrong that I expected something much more difficult). And the benefits are huge: faster work and a better finish.
If you are a hobbyist like me, and are experienced and comfortable using an orbital, the jump to a rotary is not that big of a leap. I'm glad I did it and I look forward to learning more about how to use it.