Polishing Aluminum

[Eldon]

Besides time and patience what materials etc do you folks use to polish your aluminum. Let's assume some bar stock off the shelf. Does it make any difference if the aluminum is harder?

Thanks!

[mac639]

Hi Eldon....
I'm sure there will be lots of opinions on this subject. Here's what I do. I bought a bunch of sanding blocks from Lee Valley. They had a sale on and I got a whole bag of different sizes and grits for I think it was about $10.00

I use them wet. Just get a plastic dish or a small Tupperware container. Put some warm water in it and a few drops of dish washing liquid. Start with a fairly coarse one and work your way down to a fine one, usually only 2 or 3 grits will do. After that get a container of Mothers aluminum polish (made for mag wheels etc.) Use it sparingly, you don't need much. Keep the same old cloth to use over and over. Then I use an old bath towel to polish the part. You've got to shine it quick before the polish dries too much. Sometimes for small pieces I use a cloth wheel mounted on my lathe splndle. Oh yeah, I often file the edges of pieces with a big fine file to take out saw marks etc.
It's a messy business, everything gets black but it comes off your hands OK with dish soap and water.
I don't know much about doing polishing with harder aluminum pieces. Only thing I know is that if the aluminum is anodized forget about polishing it. I got some nice angle at RONA one time. Couldn't make it shine, finally had to use the belt sander to get the top layer of anodization off first.
A random orbit sander with wet/dry paper on it works OK too but will still leave swirl marks.
I guess just keep trying different methods until you get one that works for you.
Cheers,
Mac

[Bent]

I dry sand with grits 220, 320,400 and 600. It makes shorter work of it when I can sand small parts on the disk sander at 220 and 320.
after sanding I do the buffing thing. I have 3 different fibre buffing wheels: A fairly hard one for the coarse, a medium fluffy for the medium grit and a very fluffy one for the fine grit. The compound comes in Sticks: Black for coarse, brown for medium and white for fine. By the time I hit the part with the brown stick, the shine starts to really show. Then the fine after that puts a finish shine on it.
If shiny is your thing then I would suggest this course of action. The buffing takes a good deal of practice to perfect. I am no expert after finishing 2 guitars this way. I believe that the project I am currently working on will be a bit nicer than the former one.

[mac639]

Hello again....
Just thought I'd let y'all know that I'm completely "out of business" for I guess the better part of the summer. Emptied my shop....all in boxes etc. in our daughter's barn. No repairing, no building, no selling.....I'm going nuts!! Probably will have our house on the market in the next couple of weeks. Have to get the roof replaced yet after the amazing and horrid windstorm last Thursday.

Mac

[Pat Comeau]

I've done alot of polishing since i started making steel guitars and i've tried several different methods , i've done Mac's and Bent's methods and they all do a good job, water sanding going up in grits is the most time consuming IMO followed by Bent's method of 3 type of buffing wheels and 3 type of polishing compounds ,i will tell you a few tips that will save you alot of sanding and polishing time, after countless hours of sanding and polishing i have found that i only need to sand to a 400 grit maximum higher than that is a waste of time if you have the right tools to work with, here's is what i use these days for buffing... (Treated Spiral Sewn Buffing Wheel) these are harder than standard spiral sewn and cuts 10 times faster when use with black emery compound, i've done all my polishing with only one type of buffing wheel and one type of polishing compound and everything came out just like a mirror, you can check my last build #4 endplates and you'll see how it shines , even Bent thought i'd used some kind of grease to had that shine , one very important thing about polishing is you got to have good lighting to be able to see your piece for any small scratch that your eyes can't see with normal lighting and that's why i prefer to do my polishing when it's a sunny day and use the sunlight, and i also use a paste compound called (autosol) after to clean the piece and get ride of any small blurry or cloudnest that i might i've missed.

trials and errors is the key to success

Pat C

[mac639]

Pat....sounds like you've got the easiest method on the muscles! Where did you get the treated buffing wheel and the compound? Autosol, I seem to remember seeing that stuff at Canadian Tire, it's an old brand of cleaner I think.
Mac

[Pat Comeau]

Pat....sounds like you've got the easiest method on the muscles! Where did you get the treated buffing wheel and the compound? Autosol, I seem to remember seeing that stuff at Canadian Tire, it's an old brand of cleaner I think.
Mac

Mac,
i buy those buffing wheels from Caswell Canada
http://www.caswellcanada.ca/shop/treate ... wheel.html

and autosol at CT

Pat

[mac639]

Thanks Pat... there's some good information and stuff for sale on their site eh.

Mac

[Eldon]

Before I read Pat's message I went, 320, 600, 1200, 1500 for wet sanding. Polished it with a green compound from Samoa, finished it up with Mother's. I'll try Pat's suggestion on a piece of scrap just to satisfy my curiosity.

One thing I have noted though is not to mix compounds and wheels.

Found a spiral sewn wheel in my "stores" and like Pat says it works great.

I'm finding tat a fairly light touch is also needed.

Thanks for the info guys and unless someone else has something to add I'm "good to go".