Aluminum Valve Cover Question

[ptim]

Originally Posted by mpierich

Personally I'm not sure how these angle grinders are being used. Surely they exceed the rpm limits for normal cotton wheels, and 20,000 - 30,000 rpm is, um, overkill for simply polishing. But, as the name implies, they are the best for grinding...which is what they're made for.

If these valve covers are all you're doing, you can do it with the drill - it'll just take a while. After all, Caswell sells a kit just for using a drill, so they must think it works...

If you're going to do very many more parts, _then_ it might be worth it to get better equipment.

My Dewalt Grinder is 11,000 rpm's, I ordered an adapter and a few pads from Caswell. My drill was'nt getting it done. It is only pushing around 3,000 rpm's, I probably put about 5 hours on just one of my covers.

[UncleJimmi]

The angle grinder you see in the photo (9217) is
variable speed 1500 to 3000 RPM's
The newer model (9227) goes even slower, a crawling 600 to 3000
I like the feel and size of the older ones.
They are both listed as 7 inch SANDER / POLISHER
The wheel on the one in the photo is approx 10 inches and I have used
up to 14 inch wheels, outright abusing these machines.
I have run them until the dust inside gets so bad that they catch on fire.
I quickly get them to the sink (unplugged) and pour water directly into the side vents.
Then it gets a good cleaning complete with new brushes and goes right
back to work.
That is a 480 lb. SS anchor being polished and that machine has polished square miles of metal.
Caswell has plenty of buffs that will mount right on without any adapters.
It has a 5/8 shaft and you can get an extension to move the buff a little further away from the machine,
almost needed for the newer (9227)
Drills can still be very useful, but they can't keep up with these
grinder / polishers.

[ptim]

I put a small 4" pad on my Angle Grinder, I was amazed at how much better it worked than my drill. How will I know when to stop using the darker colored compounds and use only the white compound.

[alabama_lowlife]

use a particular compound until you have removed all of the scratches left by the previous compound. it's easier to tell if you polish perpendicular to the previous stage. if you jump to the next compound before you get all the scratches out, you'll have to spend alot more time trying to get them out.

[Tng21]

Never new you could do that, fix a wheels to a grinder, looks a bit easier for the things im gonna be polishing.

Can you take a pic of the fixings on them for me please? the adapter you need to put a wheel on i mean

Cheers

[ptim]

Is a 8" pad better than a 4"-6" pad, or is bigger better. Also, are more expensive pads better, after using my grinder with a 4" kind of cheap pad, I noticed that I had tiny strings all over me.

[mpierich]

Originally Posted by UncleJimmi

The angle grinder you see in the photo (9217) is
variable speed 1500 to 3000 RPM's
The newer model (9227) goes even slower, a crawling 600 to 3000
I like the feel and size of the older ones.
They are both listed as 7 inch SANDER / POLISHER

Answers that question - to me a grinder is high speed; sander/polisher is what you're talking aobut. Carry on.

[ptim]

These valve covers are beating me. Since only parts of it can be seen, I'm not polishing the whole covers. Also they have several tiny pits in them. I can get them to a certain point, then it takes forever to get a good shine. Maybe I'm expecting too much from them. The bad part is, I'm still working on just one.

I have tried to take pictures of them, but the pictures make them look a lot worse than they actually are.

I'm almost to the point of giving up and having them powdercoated.

[UncleJimmi]

Originally Posted by ptim

Is a 8" pad better than a 4"-6" pad, or is bigger better. Also, are more expensive pads better, after using my grinder with a 4" kind of cheap pad, I noticed that I had tiny strings all over me.

The strings and dust are normal, however as mpierich pointed out I am using angle polisher / sanders not grinders, and they are variable speed.
DO NOT run wheels bigger than 4" above 3000 RPM's
Its bad for the wheels, the machine, and the part you are buffing and it could hurt you as well.
Valve covers are often the worst castings you will ever see.
I am always disappointed that they don't come out brighter for the amount of work they require. You can almost never get the kind of reflection that you can read the newspaper in. Castings are made of a million pits, I always tell people it's like slicing Swiss cheese, and no matter how many times you slice it you are always going to have the holes.

[mpierich]

Originally Posted by UncleJimmi

Valve covers are often the worst castings you will ever see. I am always disappointed that they don't come out brighter for the amount of work they require. You can almost never get the kind of reflection that you can read the newspaper in. Castings are made of a million pits, I always tell people it's like slicing Swiss cheese, and no matter how many times you slice it you are always going to have the holes.

Actually I've run into a couple of aftermarket ones that weren't too bad - could definitely read the paper in them. But then I don't get out my magnifying glass too often...

What do you use for rough work on valve covers? I had to home-build a 6x48 belt sander with foam drums to keep from getting ripples. It's also a lot faster than a palm sander.