I just started my own polishing in 2009. I had restored several bikes (30 or so), but had been getting the covers, hubs, and fork lowers all done by a local shop. This past summer, my local shop raised his prices and gave me a long-lead time for some of the covers I needed done. He quoted $300 for the Suzuki engine covers shown here. I drew the line in the sand and said I'd buy the equipment and do them myself.
I am so glad I did - the results are actually better than what I was paying for. If you'll notice the stator cover in the front and the cyclinder - those were done by my local shop. Not bad, but certainly not what I did on the front sprocket covers.
Here is what the owner of Tar Heel Parts (buffer and long-time buffiing supplies dealer) taught me when I purchased his entire system.
1) The buff wheels cannot be contaminated with different grit compounds. In other words, you cannot use the same wheel for brown (cutting) and the white (polishing) compounds. A wheel must be used for only one task. Even on the same part - you cannot go from the brown to white until the part is cleaned and all traces of brown are removed.
2) The better compounds are made from animal fat. This animal fat will melt at 140F and is used for just that reason. You first start by loading the wheel with compound, then begin the buff first by getting all of the small areas and edges. As you buff, heat will rise and you want to work the part slowly and in the direction of wheel travel - not side to side, but back and forth. This will keep the heat in the part. The idea is to keep the part at about 150F so your part is continiously letting the new aggregate be melted from the buff wheel. You'll want to use 100% Cotton gloves. These are cheap white or brown work gloves sold at every discount or garden store. You'll throw them away each time, so don't get expensive ones. The cotton will insulate your hands and let you feel the heat.
Note** You'll know it's perfect when the part is not dragging and the part is not black - if you have black residue it simply means your part is too cold and you're not melting the new compound. Seriously - go back and forth, not side to side and you'll see/feel the immediate difference. The part will easy to hold, you'll retain the heat, the part will be clear, and the buff job will take about half the time. I now can do a large cover in less than 2-3 minutes.
3) Reload the wheel every 30~60 seconds. You'll be pulling it off once you have the right temp (150F) and using it to it's maximum efficiency.
4) Bufffer speed is really optimum at 1,700~1,800 rpm. I've had the cheap Harbor Freight buffers and their 3,600 rpm - they are a disaster and I DO NOT recommend them. First they are unsafe - they will throw parts at a very high speed and have bitten me more than once. 3,600 rpm is fine for a bench grinder, but not a buffer. Go with a 1,700 or 1,800 rpm buffer. I like my 1 horse power one with 10" wheels and 36" wide shaft. It give me plenty of power, the right speed, and lots of room to work the parts easily. This was less than $300 shipped with the wide buffs and compound blocks.
If you have imperfections or have bead blasted your parts, you will need to get them perfectly smooth. I will say for absolute certain that you will need to use the 400, 600, 1,000, and 2,000 paper to get back to the factory finish. While bead blasting doesn't look like it would hurt the polishing step, it creates a very rough surface that must come off of there if you want that mirror, chrome-like shine of the sprocket cover of the Suzuki.
Don't try and don't let anyone else try to buff/polish out imperfections. No one is good enough to get it perfectly smooth using a buff wheel - you'll wind up with ripples and small waves in the larger pieces. The use of sanding from course to fine using a block or a vibrating sander.
Skip of Tar Heel Parts was the best thing for my bikes - eventually I hope many of them can wear some of the covers I plan on doing in the future -
Regards,
Gordon
http://www.tarheelparts.com/
