Buffing schedule

Materials and methods for buffing high polish, catalyzed finishes. January 28, 2002

Can anyone give me a good buffing schedule for a high polish, catalyzed finishes? We use ML Campbell products and do painted and stain and clearcoat finishes. Once in a while we need a perfect finish on a top, and inevitably that means buffing it out. We used to use 3M products, but they only sell in large quantities.

Forum Responses
From contributor D:
I've never buffed the MLC stuff, but the S-W Water-White Conversion Varnish buffs great and I think that Duravar or Krystal should buff okay too. I use the 3M Finesse It II rubbing compound. This comes in tan and dark gray colors. Use whatever color most closely matches your finish, so the rubbing compound left behind is less visible.

Use the rubbing compound with a lamb's wool pad. Iíve used both Schlegel and 3M pads and noticed no difference in performance between the two on my Milwaukee buffer. After the rubbing compound, finish up by using Meguireís #3 machine glaze with a polyester pad. Iíve had outstanding results with this combination. Iíve been less pleased with the foam rubber pads that work well on the harder automotive catalyzed urethanes. These don't work as well with softer wood finishes. Stick with the lamb's wool and polyester pads for wood finishes. Obtain these products from an automotive body shop supplier. They'll know more about how to make things shine than anybody else.

Can you go through step by step what you do and how much compound you use? Do you buff it till it is dry or stop while it is still wet? What sanding steps do you take before starting with the compound? What grit?

From contributor D:
The exact schedule I use is as follows: Start with P280 in a Dynabrade to level things out. This seems coarse but works better than using finer grits for the initial leveling. I use a six inch sander to bridge more surface area than with the more conventional 5 inch. Automotive body shops use six inch sanders exclusively for this reason. The type of sandpaper is important. The three that seem to work best are 3M 255L (fre-cut gold) and 365L (purple), Klingspor PS33W, Norton Champagne Magnum (Carborundum Premier Red is identical to the Champaign Magnum and is considerably cheaper). Mirka Royal isn't too bad, but cuts less aggressively.

After the P280 go to P400, P800 and finish up with P1500. These higher grits are referred to by 3M as micro-finishing films. Find these at your local auto body supply store. With the right sandpaper, if you let the C-V dry well enough, wet sanding is unnecessary, which is a good thing since it's messy. Since you don't need water you can do this with electric sanders if that's all you have.

After the P1500 you're ready for the rubbing compound and the lamb's wool bonnet. Squirt some on the tabletop and buff away until the buffer tends to grab. At that point you need to clean the buffing wheel with a star wheel to get rid of the excess compound. If you have friends in the auto body business, watch them buff out a car--it should teach you a lot.

Follow up the rubbing compound with the Meguire's #3 in the exact same manner using the polyester buff. Wash everything down with soap and water and admire your reflection in the tabletop.

I don't recommend using P280 on a conversion varnish. Polyester, yes, but C/V, no. I think the coarsest grit to start with would be 800, then 1000, 1200, 1500. The Maquires I liked was called final cleaner or something like that. It wasn't a very coarse compound, but with a wool bonnet would go to high gloss fast. I like to finish off with 3M Imperial Hand Glaze and a flannel cloth to remove any machine imperfection and do a final overall cleaning of the buffed piece.

You have to be VERY careful buffing CV. If you go through a layer anywhere you will get the dreaded "halo" and the only way to fix it is to spray another coat (look out 5 mil barrier!). I like catalyzed urethane for just that reason. I can do the entire topcoat in just 1 coat (spray a full coat, let tack, spray another full coat, let tack, etc.). I can spray a very thick coat this way, which is important for buffing. There used to be many good urethanes for this purpose but now the best I can find is House of Color automotive urethane.

I agree with contributor D on the 3M micro-finishing films. They also make these in micron grits and you can wet sand to 9 micron, which is almost a gloss already. I use a Dynabrade 6" air sander and think that's the best. Lamb's wool rules--don't buy the fake stuff that looks like lamb's wool. If you burn a little piece it should smell like hair burning and not melt into a ball. My favorite compound used to be made by Sadolin Canada but I haven't been able to find it for years. It was Pasta Abrasiva and I could rough out my scratches in 1 or 2 passes. I use 3M and DuPont and Mezerna now.

The comments below were added after this Forum discussion was archived as a Knowledge Base article (add your comment).

From contributor A:
Another pad that works great on wood for buffing and polishing is Surbuf with Microfingers. Unlike wool pads, the Microfingers are mounted vertical on the pad surface and each MicroFinger is independent so they flex and stiffen as they move over the surface. This produces an even depth of shine to the high and low points on surfaces. These pads will also perform using half the amount of polishes as the wool pads, don't heat up the surface as much so burning is not an issue, and they are easier to clean (ust use an ordinary pocket comb and hold it to the fibers while spinning the pad). Surbuf pads can be used on high-speed machines when needed but for most work we recommend the use of a random orbit machine.