polishing side covers

farm dog

Member
Been polishing clutch cover , striped & sanded down to 1200 paper then ultra fine . Started buffing with red , getting small lines from buffing ? I rake the wheel about every 2 min. Doing something wrong ? Fine lines were not left from sanding . Doing this with a 4" wheel in a drill ( RPM ? )
 

69ST

Well-Known Member
Different alloys require different compounds. Both ambient temperature and wheel speed can have big effects.

I've found clutch covers to be fairly forgiving, as aluminum parts go. However, let's be clear...I've been polishing metal for almost 50 years and have an extensive inventory of wheels, compounds, sanding wheels & belts, etc. There's no point in trying to get too involved with specifics and "what ifs", it'd induce a migraine, as well as a big invoice. Metalfinishing & polishing supplies really add-up in a hurry.

That said, first thing I'd try is a different compound...Tripoli. That works well on most hard aluminum alloys. If that doesn't work, or, you want something more immediate, then switch the Mother's Mag & alumimun polish. You may have to sand with 2000-2500, first but, with elbow grease, it'll work wonders...and with a minimum cash outlay.
 

cjpayne

Well-Known Member
Different alloys require different compounds. Both ambient temperature and wheel speed can have big effects.

I've found clutch covers to be fairly forgiving, as aluminum parts go. However, let's be clear...I've been polishing metal for almost 50 years and have an extensive inventory of wheels, compounds, sanding wheels & belts, etc. There's no point in trying to get too involved with specifics and "what ifs", it'd induce a migraine, as well as a big invoice. Metalfinishing & polishing supplies really add-up in a hurry.

That said, first thing I'd try is a different compound...Tripoli. That works well on most hard aluminum alloys. If that doesn't work, or, you want something more immediate, then switch the Mother's Mag & alumimun polish. You may have to sand with 2000-2500, first but, with elbow grease, it'll work wonders...and with a minimum cash outlay.

Nearly every time that I've painted a clutch cover, Ive had to fill a nic, deep scrape, or dent with JBweld, then the usual sanding. If your polishing, what would you use to fill those that wont rear its ugly head and just blend right in? Electrical solder? Skillfull melting with a small crackpipe torch? Make the wheel burn it away?
How do you get between the lettering without burning the lettering away?
With my skillset for polishing, I'd have to start out with a brand new cover.lol
 

69ST

Well-Known Member
Nearly every time that I've painted a clutch cover, Ive had to fill a nic, deep scrape, or dent with JBweld, then the usual sanding. If your polishing, what would you use to fill those that wont rear its ugly head and just blend right in? Electrical solder? Skillfull melting with a small crackpipe torch? Make the wheel burn it away?
How do you get between the lettering without burning the lettering away?
With my skillset for polishing, I'd have to start out with a brand new cover.lol

That's what makes metalfinishing a skilled-labor-intensive process. You ought to try doing your own prep for chrome...talk about humbling(!):30: Every little flaw not only shows up, it's magnified. With chrome, however, you can use copper, welding, brazing rod, or copper to fill pits & scratches. When dealing with polished metal, not plated, welding is usually a remote and impractical possibility. With thin material, such as steel, stainless, copper, certain aluminum alloys, it's possible to dolly-out most of the imperfections. Then, it's time to level-out the surface with progressively finer abrasives (a.k.a. metalfinishing) then polishing. With castings, it's sanding, followed by more sanding, until you either achieve a uniform surface, or decide to live with a few flaws.

Different alloys have to be worked differently, I can't really break it down further than that. There is a certain amount of trial and error, until you get at least some experience with a specific alloy. Some aluminum alloys are downright temperamental when it comes to polishing. Honda engine castings are hard and on the brittle side. If you get galling, time to try a different combination of compound, wheel type & speed. Polishing a clutch cover is a helluva lot of work. Retaining the lettering slows the process even further; that's why most of polished specimens you see lack the lettering...it's far easier to just sand it smooth and go from there. Sometimes, that's where the men are separated from the boys...unless it's a cover that just didn't have the lettering in the first place, or the letters were damaged. How to work around them...slowly, using wheel compounds and a series of small/thin wheels. Sometimes, it's impractical to get every little recess and you'll just have to live with a certain amount of "less-than-perfect"...or spend days sanding between individual characters.

Don't kid yourself, even a new clutch cover can take 4-8 hours to transform into mirror-like "perfection". I polished the billet triple trees on my daily rider, turned `em into mirrors, literally. Best I've ever been able to do is 2-3 hours PER SIDE. That's starting with new parts, finely CNC machined and surface imperfections no more than a few thousandths of an inch deep. Want motivation to limit your polishing projects...or really dive into the deep end of polishing, try a CT70 wheel hub. Those tight-radius, concave, recesses will put one to the test.

No joke, polishing is more of a skilled craft, and painstaking work than most realize. IMO for most guys, brake plates and the occasional folding bar clamp/triple tree, or points inspection cover are sufficiently challenging...and satisfying, once done and luckily all the polishing needed on a stocker.
 

scooter

Well-Known Member
Agree - Just spent couple hours working on two sets of shocks. I do like my 3M silicon carbide soft wheel to get things started. Well worth the money. I use it before I start working with the various compounds etc.
 
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timmmy

Member
So I was just fixin to polish the head up (keep the thread clean) on my rebuild. This isn't looking so easy!

racerx, any pointer for this project?
 

69ST

Well-Known Member
So I was just fixin to polish the head up (keep the thread clean) on my rebuild. This isn't looking so easy!

racerx, any pointer for this project?
Are you talking about metalfinishing & polishing the entire head casting? If so, you may claim proud ownership of the understatement of the year award(!).
 
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