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Davek0974
07-14-2014, 01:53 PM
Looking for suggestions for finishing ally plates.

I'm plasma cutting some shapes from 3mm alu 1050 plate, there is some mild dross on the back and sharp edges all over.

I have heard the pro's would use a graining machine which I'm guessing is like a belt sander with a belt feed, don't have one of those though;)

Is there a method of deburring and providing a pleasing finish I can do at home in the shop?

Currently I'm doing it manually with a file first then tidying up with a sanding block.

The parts are triangular around 8" x 8" and I have the possibility to need quite a few of them.

gvasale
07-14-2014, 02:34 PM
A Timesaver is the type of machine that does what you want. It will look the best if you find a sheet metal shop that does this. Belt sanding by hand wont look so good. "Engine turning" like on aircraft panels like on The Spirit of St. Louis would be outstanding, but not likely to be worth the effort.

Davek0974
07-14-2014, 02:43 PM
Thanks, but I really need to do this in-shop, wherever possible I try and do it all at home, increases profits, increases knowledge and flexibility too :)

Old Hat
07-14-2014, 02:46 PM
sandblast from a distance and at an angle.
so as not to warp plate.
then heavy coarse steel brush by hand.
long strokes one direction only push down medium hard.

topct
07-14-2014, 02:59 PM
A vibratory tumbler with the right media might do it. I don't what media you would use as far as shape or grit though.

Davek0974
07-14-2014, 03:21 PM
Thanks, have thought of tumbler but don't want to remove the corners of the plates as well as the dross etc.

I think a wire brush could work, I'll try that on some scrap.

Maybe even some sort of frame to hold them steady and a gentle flap wheel on a grinder.

topct
07-14-2014, 03:30 PM
A vibratory won't remove the corners if you pay attention to how long you leave it in the tumbler. And this is going to take more than one step to get them anywhere anyway.

Wire brush on aluminum? It won't like it or the flap wheel.

Davek0974
07-14-2014, 03:46 PM
Hmm, ok, just thinking ;)

How's about an orbital sander with emery cloth fitted?

Might work, I've got a pile of scraps to play with so could be worth a go. If it's wet with something like wd40. It won't clog up.

Beone
07-14-2014, 03:46 PM
A plain old 5 inch random orbital can do a good job

cameron
07-14-2014, 04:10 PM
Maybe you should find out what your customers would like, or at least what they will tolerate. If you tried to sell me the type of commercial finish that hides minor blemishes with linear scratches, I might say "No, thanks!"

Or maybe I wouldn't, depending on the price.

oxford
07-14-2014, 04:25 PM
A plain old 5 inch random orbital can do a good job

I have used this before and it does do a decent job. It is probably one of the least labor intensive ways to get a consistent finish on aluminum.

As for the edges, I would probably hit them on a belt sander to get them consistent looking from the plasma cut. I would then make a decision on what to use for what burr is left and how I wanted it to look. The belt sander will take care of it if it is a decent burr, if it is not too bad I would consider using a "carbide burr" in a Dremel type tool.

Davek0974
07-14-2014, 04:26 PM
Maybe you should find out what your customers would like, or at least what they will tolerate. If you tried to sell me the type of commercial finish that hides minor blemishes with linear scratches, I might say "No, thanks!"

Or maybe I wouldn't, depending on the price.

It's not an issue with this item, as long as it looks tidy it will be fine.

It's hidden when in use, so appearance is purely "first impression" stuff.

Davek0974
07-14-2014, 04:28 PM
I have used this before and it does do a decent job. It is probably one of the least labor intensive ways to get a consistent finish on aluminum.

As for the edges, I would probably hit them on a belt sander to get them consistent looking from the plasma cut. I would then make a decision on what to use for what burr is left and how I wanted it to look. The belt sander will take care of it if it is a decent burr, if it is not too bad I would consider using a "carbide burr" in a Dremel type tool.

Would you use the sander dry?

I have a feeling that deburring the edges on the belt sander then drill the fixture holes, tidy the apertures with a file and then hit it both sides with the orbital sander. That would likely remove the last of the fine dross/burrs.

Will try it out.

gvasale
07-14-2014, 04:45 PM
Guys, 3mm is thin material, I tend to think this is sheet stock, not plate, but only guessing, so it will require some careful handling. However, before you discount Timesaving, check and see what the cost would be. It is a quick operation. Will take more time for you to clean up than the process itself. Not that long ago I was deburring aluminum panels that were about 12" x 72" and the best way to deburr a waterjetted perimiter was with a hand held file, draw filing across the edges. Way better than and belt sanding. My customer said so.

Bob Fisher
07-14-2014, 05:09 PM
I'd hit the edges with a belt sander,and finish up with an orbital sander. Gives a pleasing looking finish. Try a relatively coarse paper and work down to what works. For you. Bob.

Rosco-P
07-14-2014, 06:42 PM
What would be wrong with cleaning up the edges with a three corner scraper or a deburring tool like a Shaviv or Vargus. Leave a nice small chamfer. Is there any need to remove or hide the mill finish on the Al?

boslab
07-14-2014, 07:16 PM
A bosch sanding roller is a good alternate, not too expensive, 90 in Argos
http://youtu.be/ONUZWOOhzxc
Mark

Toolguy
07-14-2014, 07:36 PM
I would use a ScotchBrite wheel for the edges and a ScotchBrite belt on a belt sander for the flat surface. Quick and easy, not much cost.
For the flat part you could make a holder to drop the parts in (maybe 2mm deep) and run a portable belt sander over them.

metalmagpie
07-14-2014, 11:33 PM
I also recommend the use of e.g. 240 grit sandpaper on a random orbital sander. It leaves a very nice looking matte finish. My daughter (a very good cook) made a custom birthday cake for the son of a caterer. She didn't have a platter big enough so I cut her a piece of 1/4" 6061 plate about 12x24" and hit it with the RAS. The caterer liked the cake but LOVED the platter, wanted me to make her six of them!

metalmagpie

Rich Carlstedt
07-14-2014, 11:49 PM
I would use a ScotchBrite wheel for the edges and a ScotchBrite belt on a belt sander for the flat surface. Quick and easy, not much cost.
For the flat part you could make a holder to drop the parts in (maybe 2mm deep) and run a portable belt sander over them.

Plus 1 ! for Toolguys suggestion on a ScotchBrite Wheel
Use it on the edges, parallel to the wheel and you will be done in no time and you don't have to touch the flat portions of the work

Rich

boslab
07-15-2014, 12:49 AM
Or if you want really cheap, pearl caustic soda and a tray, mix it up with cold water, wont be cold for long as its an exothermic beast, dip plates in to give a matt etch,myou can even draw patterns on with a marker that wont etch if you fancy, no cost at all really
Usual safety stuff applies, pour down a clogged drain to dispose of and clean the drain
Mark

Davek0974
07-15-2014, 03:55 AM
Nice suggestions, thanks.

That Bosh sander looks useful too, never seen that one.

These are plasma cut so at least the back needs cleaning up and facing. I have tried a Noga deburring tool but the apertures are quite small and it did not work as well as I'd hoped. A three-square file works but is time consuming.

The edges and edge dross is easily dealt with by a quick flash against the belt sander. I have a feeling the orbital sander will do the rest, will be trying it out tonight. A mounting frame is easily made with scraps and a bit of ply etc, that will hold them flat and safe from bending.

Thanks again.

vpt
07-15-2014, 07:58 AM
I use the wire wheel on the bench grinder to take the dross off and round edges on aluminum.