[delraydella]

If you're looking for a different way to finish off an aluminium project where the framing is seen, like furniture, other than just spray painting it, this is a nice, fast and cheap way to get a durable and nice looking finish. I've been doing this for the last 10 years and so far no complaints.

Wipe down all the aluminium with lacquer thinner, then take a random orbital palm sander with 60 or 100 grit paper and sand the surfaces. 60 and 100 work the best, anything higher generally can't be seen very well. 150 might be as high as you would want to go. You don't have to press down too hard, but have plenty of sandpaper ready, the aluminium will clog the paper eventually. When you're done sanding, spray it with a clear lacquer to protect it. 2 coats is usually enough. After you've sanded and before you spray, you have to be very careful about smudges on the aluminium, so wash your hands before you handle it. Any smudges will have to be sanded out again. The picture shows the difference between plain aluminium on the left and sanded and sealed on the right.

If you notice on the picture, I also routed a roundover into the plate. If you've ever dealt with plate aluminium that has been sheared , you'll know why I did it!
It also makes a nice finished edge. Any router bit that is carbide tipped will route alumunium, but make sure you use a bit with a ball-bearing guide. You might have to make 2 passes for deeper cuts.


Steve

[ogorir]

nice. a little stick lubricant or a spray grinding oil will keep the paper from loading. I've never stopped there, but I've semi-polished (up to 600 grit, then scuff over it with 1500) or 'ghetto engine turned' (sanded perfect to 320, then a coarse scotch brite abrasive disc) a bunch of stuff. I'll keep this in mind.

[delraydella]

I'd like to find a cheap used surface grinder and try to fit a wire wheel on it for a brushed look. I've tried to do it with a wire wheel on an angle grinder, but it always winds up looking like I did it with an angle grinder.

[Otto Nobedder]

I've gotten decent results using a wire cup on an angle grinder while running the grinder against a crude fence.

I've also used a D/A with 60 grit the same way on stainless, just moving the fence in 2" increments.

Steve

[turbo388]

Green scotchbrite. The dish scrubbers with sponge on one side work best, wet - brand new ones are a bit too aggressive, use one that's broken in and a little 'fuzzy' and it gives a nice flat finish with no visible scratches. A new pad dry, new pad wet, broken-in pad dry, will all give you a different finish, you may like one more than another. And scotchbrite doesn't load up with crud.

[karlevo8]

been doing this for years personally hate polished ali i use a red scotch pad on a da for a semi sheen for brushed look i just hand draw a scotch pad up and down one direction

[TheExpert]

Aluminum can be surface finished in many different ways. The most important types are mechanical, chemical, electrolytic oxide and organic finishes.

[turbo388]

Aluminum can be surface finished in many different ways. The most important types are mechanical, chemical, electrolytic oxide and organic finishes.

Excellent post, RandomKeywordGenerator! (just like all the others by this... user)

[TamJeff]

I think the red scotchbrite on a DA is my favorite finish on aluminum. Gives it a nice matte finish. This was a balcony rail sample for 400' of it. It especially helps blending irregular mill finish with all the import crap that they send down the line these days.



I have to do quite a bit of aluminum finishing. Mostly edge treatments where exposing raw aluminum on polish finished anodized flat bar. Typically a couple different grit treatments followed with brown rouge on a sisal wheel. Most places in my industry don't bother. Sanded edges just look odd on new constructs against mirror finish everywhere else.

[delraydella]

What do you think would be the best way to take out lathe chuck indentations from 6061 aluminum rod? The pieces I'm making need to be a smooth polished finish. I've tried buffing them out, but they are a little too deep for just that, but are probably only about .001 deep, if that

Here's some pictures that show the indents.

Other Steve

[TamJeff]

There's only two ways I know. Either sanding and blending or filling, sanding and blending. Is there a spiral grit or brushed finish on it already? If brushed, maybe a DA with 80 grit followed with emery cloth.

[Otto Nobedder]

Steve,

I'd aim for prevention, rather than remedy.

Get some copper tubing. Make yourself some jaw liners for the lathe.

Steve S.

[delraydella]

Steve,

Copper jaw sleeves are a good idea, I'll try that tommorrow. I was thinking about trying to make some sort of split sleeve compression tube that would press down on the aluminum as the jaws closed and hold it tight in the chuck, but if that or the copper sleeves don't work, I'll have to shell out the dough for a new chuck that can take soft jaws. The chuck I have now isn't adaptable for soft jaws.

The order of machining steps is whats ultimately screwing me.What should logically be done almost last has to been done early in the process and to change the order would add a lot more time consuming tedious steps.

If anyone is interested, I'll post the story/ pictures of this project in a seperate series of posts. There is absolutely no welding involved in any of this, so I'm not sure if it would be appropriate on these forums, but if there is an interest, i'll do it.

Other Steve

[Otto Nobedder]

"General Shop Talk" would be a fine place to post it, as it doesn't fit the other categories...

[delraydella]

Steve,

The copper jaw sleeves worked like a dream! THANK YOU!!


Other Steve

[Otto Nobedder]

You're quite welcome, and I'm glad it helped.

Nice job fitting them, by the way!

[delraydella]

Thanks! It's a nice tight pressure fit on the jaws. I didn't want to glue them on, but I also didn't want them to keep falling off into the chip pan every time I took a piece out. I also think this was the first time in quite a few years that I used a ball-peen hammer for what it was intended for!

Other Steve

***This is something that I discovered some time ago....It's really easy to take out chuck jaws , but you almost need 6 hands to get them back in and tracking evenly in the slots. A couple of heavy rubber bands wrapped around the jaws will apply even pressure to all the jaws as you turn the chuck key to get them back in.

[TamJeff]

That's a good idea.
I misunderstood. I thought you meant you had to fix the one rod, like there wasn't anymore. And those copper pads did come out nice. That's the lure to welding for a lot of people. You get to see a lot of people that care about their work.