PC 7424 Pads vs. Backing Plate confusion

[Inzane]

I have a PC 7424 from Coastal Tools kit, which comes with the extra counterweight (6") and the 6" backing plate (#18002).

I have a couple Meguiar's W-8006 yellow polishing pads. I also recently acquired a few Lake Country pads: the standard durofoam VC pads (as CMA calls them) # 570VC, 670VC, 770VC (the yellow cutting, white polishing and black finishing).

1. First observation. The Meguiar's pads are bigger, they seem to be 6.5" as advertised. But the LC pads are only 6", so why does CMA advertise or refer to them as 6.5" pads on their website (referenced in several places)?

2. Is the 6" backing plate the right one to use with these 6" LC pads? I test fitted one last night and the edge of the plate is flush with the edge of the pad. NO room or margin for error on the edges. The Meguiar's pads at least give you a little bit on the edge.

I switched to the 6" counterweight and it made a noticeable difference in vibration just by test running the machine in my basement. (very cool). Am I going to need a 5" backing plate now, based on the pads I have? I'm sure this 6" plate will be fine for the 7.5" advanced pads, but I wasn't going to get any of those in the near future. I wanted to experiment with the standard pads first while I learn.

3. I've seen people reference the W-8006 polishing pad for a variety of applications from using DACP (one of the most agressive products people use with a PC) to using it to apply a LSP (last step product) like NXT. Why is that? Is the Meg's pad just that much more versitile? Is it more agressive than the LC white pad? Until I noticed the 8006 getting used for everything I was used to seeing people be more specific when using LC pads - yellow for DACP, etc., white for GEPC, #7 or FP, etc., and black for final wax or sealant. This difference in approach is a little confusing to one who has never used a PC before.


Thanks!

[Macgirl]

Just a few comments....

1. First observation. The Meguiar's pads are bigger, they seem to be 6.5" as advertised. But the LC pads are only 6", so why does CMA advertise or refer to them as 6.5" pads on their website (referenced in several places)?

CMA sells a standard pad (lambswool, yellow, white, & black) that is indeed 6" and that is how it is advertised. However they also sell the orange power pad and the Green Giant pad which are 6.5." Then finally they carry the 7.5" advanced pads. You may just be looking at all the different pads and getting them confused as to the size of each.

2. Is the 6" backing plate the right one to use with these 6" LC pads? I test fitted one last night and the edge of the plate is flush with the edge of the pad. NO room or margin for error on the edges. The Meguiar's pads at least give you a little bit on the edge.

You can use them together but it is wise to use caution since there is no buffer between pad and plate. It may be wise to go with a 5" plate for the 6" pads. You can safely use a 5" plate with 6"- 6.5" pads.

I switched to the 6" counterweight and it made a noticeable difference in vibration just by test running the machine in my basement. (very cool). Am I going to need a 5" backing plate now, based on the pads I have? I'm sure this 6" plate will be fine for the 7.5" advanced pads, but I wasn't going to get any of those in the near future. I wanted to experiment with the standard pads first while I learn.

If you have both weights just play around with both and decide which works better for you. I think the Porter-Cable formula is to use the 6" weight with a 6" backing plate and the 5" weight with a 5" backing plate. But, that may have to do more with the sanding discs rather than foam pads.

I can't answer the last question you have. I really don't know that much about the foam composition to give you an educated answer. I have a Meg's burg. cutting pad and the yellow polishing pad but haven't had the chance to use them yet. Maybe someone else can help with that one.

Hope this helps

[bretfraz]

The combo of pad/polish/speed/pressure is not an exact science nor is there a formula. It's all part of the art of detailing. Since no two cars/paint jobs/detailers/expectations are alike, its up to each user to find a system that works for them.

One thing I like about the Meg's yellow pad is I seem to get consistently good results using a variety of polishes, speeds, and even machines. It works well with both rotary and PC. But this is mostly due to my comfort level with the pad. You need to find your own comfort level and that will come with experience. You'll feel better about PC polishing when you've spent more time actually using the machine than just reading about it.

CLIFF NOTES: Use whatever pad with whatever polish and find a combination that works for YOU.