Hi
Two questions about aluminium sheet approx 1mm thick.
Can I cut it using my table saw with a TCT blade and/or will doing so blunt the blade rapidly?
Can I get a polishing mop to fit a 115mm angle grinder, so I can mirror finish it?
Dave
No, it won't blunt the blade. You will have to be very careful of feed rate and support, though, or you'll get wobbly edges, to say the least.
I doubt that'll mirror finish it - maybe make lots of polishing marks in it. Use flour grade wet'n dry (if need be) with plenty of wayer with a drop of hairy lipsquid, then brasso on a clean cotton cloth by hand.
I thought paraffin was the fluid for working aluminium?
Roger
I meant Brasso for polishing - it's a very good start. I'm sure there are other suitable polishes...
Hi Chris
Thanks - I'll watch those points - I have enough wobbly edges as it is!
I was trying to avoid the 'by hand' method. I saw on The Caravan Show the other night someone mirror finishing aluminium with what looked like an angle grinder, but the pad was at right angles, The pad appeared to be discs of cloth stitched together.
Dave
I really wouldn't do this - there's a kickback risk. If you get the right sort of sawblade (negative tooth rake) then it's easy and safe. You won't "blunt the blade".
It will be incredibly noisy though, especially on a saw that's less than perfectly rigid!
You'll also want something like a Dreadnought file (a coarse-toothed curved tooth rasp) for working the edges. Aluminium benefits from new, sharp coarse files and rubbing the teeth with chalk before beginning. The teeth tend to "pin up" with aluminium, so the rasp stays cleaner.
No, the angle grinder is much too fast.
There are useful nylon bristled abrasive-loaded rotary brushes you can get to use in a hand drill. These are excellent for copper, but aluminium is just a bit too soft - you can too easy put obvious swirl marks in with them.
I suggest a range of hand Garryflex blocks instead (also made for Roebuck), rubber blocks full of abrasive grit in a range of grades. Aluminium is soft enough that doing it by hand doesn't take long, even for large pieces. Make sure you use the coarsest first and don't go finer until you've got the last of the scratches out. A mirror finish is easy and only takes moments, a good unscratched mirror finish takes more care and effort.
Either keep separate sets of blocks for ferrous and non-ferrous metals, or rub then clean when swapping over - otherwise you get black smears.
Look after your aluminium when you're working on it (masking tape etc. do avoid scratching where you're working). It's easier to not put big scratches on than to take them off later. Emery or wire wool will shift them, if you have to.
Easier to get an accurate cut with decent tinsnips? Or if well supported a jigsaw with suitable blade?
I'd be very worried about a table saw 'grabbing' and throwing things every which way.
Most polishers run at a low speed to avoid burning the polisher and paste.
I'd try a random orbit sander with a lambs wool bonnet.
That's a rag buffing wheel, I have no idea what it's mounted on - note that your grangle winder whizzes around at at least 10,000 RPM, so it will be a bit tasty on aluminium. What about a car polisher? You can get a thing called a "Power Devil car polisher" if it's no good or breaks, take it back!
Grinders run much too fast for polishing.
have. Clamp or screw the sandwich together. It will then cut fine for you
Paul Mc Cann
read this a while back and thought it was interesting
So you are really going to be polishing the oxide or corundum, the trick is not to do anything that will cut/scratch through the coating I guess
Paul
'e wants to polish the *metal* to a mirrer finis
You can't.
The moment the metal is exposed to the air, it forms a coat of oxide.
Want to bet? A quick Google will show many interesting things...
Hm. Yet there's plenty of polished aluminium about. How *do* they do it :)?
On 10/06/2005 12:35 Chris Bacon gurgled:
Solvol Autosol is the stuff for polishing aluminium used with a 3" felt wheel (Black and Decker make one) that fits your leccy drill using the same arbour as a grinding wheel. You may need to finish with a bit of Solvol Autosol on a cloth to remove any polishing marks but it is easy.
Used to get a chrome-like finish on engine castings when I was a biker.
Parish
Sure. Whatever you like.
You're looking at a coat of aluminium oxide. The fact that it's a nice optically flat one due to the metal beneath being flat also is irrelevant. It is simply impossible to have a bare coat of aluminium metal in air.
So aluminium oxidises in air, and you can't polish it. Other metals also oxidise in air, so are you saying it's impossible to polish them? If not, why not?
Probably a stitched polishing mop, available from professional polishing suppliers, but I doubt the ones I know would fit on an angle grinder.
Colin Bignell
Aluminium oxide is transparent -- clear as glass. It's also incredibly hard (not far off diamonds), although the layer which forms is really too thin to provide much protection. It can be deliberately thickened by anodising, which makes the surface harder. It's a damn good electrical insulator too, which is a bad thing when trying to connect aluminium conductors.
Crumbs, someone's paying attention.
It protects against the oxygen in the air, which is what counts.
HomeOwnersHub website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.