Here’s a question almost as provacative as what brand of 2-stroke oil is best…..

[seakaye12]

That question is:

How do you clean (dress) points?

Point File? Sandpaper? Chemicals of some sort???

Lets assume that the points are NLA and mildly pitted. Since they can’t be replaced….what method should be used to clean and polish them? How do you achieve that mirror-like finish?

Thanks! Chuck

[wbeaton]

400 grit wet/dry sandpaper wrapped around a points file and saturated with carb cleaner. After sanding I spray with carb cleaner and clean with a piece of unused paper or business carb.

Wayne
Upper Canada Chapter

uccaomci.com

[outbdnut2]

I start with a file if they are really bad, then move to 320 wet-or-dry paper and finish with 400 paper. Often one contact needs more finishing than the other.
Dave

[nj-boatbuilder57]

Years ago I worked for a company that manufactured electrical contacts. Silver alloys, platinum alloys, tungsten alloys….for wall switches, snap switches, contactors & starters…..as small as a pinhead, as big as your fist: we made all of them. Fantastic science that delved into physics, chemistry, electricity & metallurgy.

The one takeaway that has stuck with me to this date: never, ever, ever use sandpaper on electrical contacts. "Sandpaper" is silica, and silica is an insulator. By using sandpaper, you are embedding insulating material into the surface of a conductor. That’s bad…just don’t.

In an application like this where carbon buildup is usually not an issue, the "cleaning" is more of a mechanical leveling…..and a fine-cut stainless steel fingernail file works great.

[rudderless]

I use sharpening stones from course to fine with oil on the stone. One point needs to be flat and the moving point needs to be convex. The points for motors are usually tungsten which is very hard. The points need to be separated to do this. The oil on the stone keeps stone particles from embedding on the point contact. Finish with the finest stone ya have…like an Arkansas stone or equivalent. I used the wives fingernail file once and since the point is harder than the file…she noticed right away the file was dull and somehow was my fault..;)

[jw-in-dixie]

One suggestion – use brown sack or = paper, not white, especially business cards. Titanium dioxide, a great insulator, is used to whiten paper. 😉

[kerry]

Points file, and a piece of brown cardboard from the back of a pad of paper.

If you have too many, AND not enough, you're a collector.

[billw]

I use 320 Emory cloth. Apparently, points are nearly has hard as a rock; because I go through a good deal of abrasive area, when the pits are bad.

Long live American manufacturing!

[chris-p]

I too use a points file, made specifically for that purpose. Follow that with paper stock dipped in acetone and then lastly compressed air.

[frankr]

Back in "The Day" it was preached never, ever to file or sand points. And I more or less went along with it–more or less. But now I do it all the time, with no problems. I disassemble the points and do one contact at a time with 400 grit wet-or-dry silicone carbide paper. Use something like a piece of hacksaw blade to back up the sandpaper and use it like a file. Any buildup on the contact should be removed, but it is not necessary to remove all the pitting on the opposite contact. After all, remember "vented points" with a hole through one contact?

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