Aluminium Polishing

[Craved]

Hey All,

So i just got myself a new abbott and ashby 8" bench grinder, bought along with that a tapered spindle, a stitched buffing pad and a loose buffing pad, some Brown cutting compound for the stitched and some White SS compound for the loose buff.

Fitted it all up and gave it a go for a small 5 minutes or so for each different Buff and compound (one section about 200mm square), stopping to wipe it all clean with Turps before starting on a different compound.

Found the actual side/edge welds came up quickly to a mirror finish but the flats sides of the washer bottle i was doing seems not to be changing much if at all with the use of the compounds and wheels.

my basic Questions are :

1. With brushed alloy material should i be using a sisal buff with a grey compound first to remove the oxidisation from welding then moving down the compound towards to mirror polishing loose buff?

2. Is the grey too harsh and i should spend more time on the brown compound before going to the white?

3. Whats an easy way to tell if more compound is required on the buffing pad?

4. could starting with a 400 or 600 sand paper assist in the polishing process? EDIT : now reading that you can use 400 - 600 - 800 - 1000 grit wet dry prior to final polishing 2nd edit : now reading that using higher than 400 grit is a bad idea - sigh

Any answers and hint would be good.

Cheers

[skylinecouple]

I used one of those little sand paper attachments with a drill.Looks like a fan sort of thing.Then 1200 wet and dry.Then a good buff and everything will look good.

[Craved]

hmmm i think i just need to spend alot more time that i thought it would take to polish these up ...

will spend some more time on it all and see how the outcome turns out.

[sinistaGTR]

i polished up the comp housing on my gt3040 with wet and dry and a few beers over a few nights lol

[zebra]

Dan

You Learnt That At Kamp-Pooka?

Didnt ya.

Andrew

[Adriano]

Just be carfull when using the compounds that you dont get it too hot, you can easily burn yourself and melt the alloy if you give it some. You can actually get the alloy to "run", although the grinder probably wont have enough grunt to cause too many dramas(ive got 2 of these hooked up together with a bit of 3/4 heater hose for more hp!)

[zebra]

lol....u should stick it on a dyno.

Just thinking of aluminium and bench grinders...whats the best way to tackle a std intake plenum on a 33....pull it off and smash it with a bench grinder?

Craved - You gotta post up some pics when its all done - Did you make it yourself?

Edited July 22, 2007 by zebra

[zebra]

Wait just read the other thread about it - woops

[Sambo33]

i polished up my alloy strut brace today. it was originally brushed alluminium. i flattened it out using 320 dry on a sander, then blocked it with 600 wet, then hand rubbed it with 1200 wet. i polished it by hand using meguiers metal polish and it came up like a mirror

ill post a pic when i fit it up

[sinistaGTR]

Dan

You Learnt That At Kamp-Pooka?

Didnt ya.

Andrew

Haha maybe......cardboard for the finish works the best but.....

Edited July 25, 2007 by sinistagtst

[zebra]

Haha.....RAAC Chrome FTW

[Craved]

Bought myself some 600 - 800 and 1200 wet/dry paper on the way to work today .. give that a shot tonight and see how we go

[Craved]

Worked on my washer bottle with thesand paper and removed most of the marks for the bender. this was working through 4 steps of paper - 400 -600 -800 -1200

then moved onto using the bench grinder and some tripoli on a stitched buff wheel.

then used the white rouge and the loose leaf wheel ... and its was still hazy and not polished

Went and bought some meguirs NXT metal polish and wow that stuff works well ... alot more work than using the grinder but really gave more shine on the areas that i did do with the paper then the grinder.

tried it on an area that i didnt sand or use the bench grinder and while it made it shiny it still held residual grain that was present in the alloy.

[18RZZ]

ok mate there is loads of way you can polish and it has been my job for around 3 years kniow the most effective way to polish anything is to get someone else to do it. However if you doooooooneed or want something polished there is a few basic things to consider.

1 onlly alloy and stainless steel should be polished

2 to polish cast mould takes a lot more work.

3 the equiptment i use for all my mirro finsh jobsconsists of...

shinano 6" sander 9000 RPM's

makita barrel grinder with spindel point

120, 240, 500, 600 grit deer round sanding pad ( high rpm rated )

air flow, sizal, loose leaf, swansdown mop ( these are all leaf, stich or rope mops )

fast cut, brown rouge, green chrome ( all cutting compoud bars )

yellow soft compound grease bar and mass finish

That is my basic set up and this will enable the prep and polishing of most stainless and alloy metals

due to some parts haveing tiny hard to reach places sometimes its easier to hand sand and buff on a bench grinders but note there is no way to polish every inch of some things.

cheers for any futher queries about metal polishing, hint or quick tips

i am available after 5 monday to friday and all weekend

cheers kingy

PH 38032143 or 0419771676

[Craved]

so how do you know when more compound is required on the buffing wheel?

[Yawn]

Anyone want to polish some pipes for me, or got any good suggestions? They already have a polished finish but they're old. I tried cleaning it with household cleaner (Mr. Muscle etc.) to get the grime off then used normal polish and elbow grease but still looks just as crappy, but slightly cleaner .

[GeeTR]

I’m never polishing anything again, at least nothing as complicated as an RB26 inlet plenum!

I calculated around 40 solid hours to complete, and I didn’t even complete the bottom of it!

- Paint stripped it

- File finished the whole thing, casting marks, letters, deep pits from the sand cast

- Used the above mentioned “fan like” paper sanding drum on the end of a drill, with a small 1” one for between the runners.

- Worked way from 400 600 800 1000 grit. Then went straight to the stitched cotton buffing wheel drill attachment. The finer cutting compound was enough ( I think because I went right up to the 1000 wet and dry)

- Came out really good, I should post some pics up.

I would never ever attempt this again, unless paid an insane amount of money.

Iv heard ppl do a little each night in front of the TV, with it on their lap, but I prefer doing it wet, the paper lasts a lot longer and doesn’t clog.

[grandmasterb]

I’m never polishing anything again, at least nothing as complicated as an RB26 inlet plenum!

I calculated around 40 solid hours to complete, and I didn’t even complete the bottom of it!

- Paint stripped it

- File finished the whole thing, casting marks, letters, deep pits from the sand cast

- Used the above mentioned “fan like” paper sanding drum on the end of a drill, with a small 1” one for between the runners.

- Worked way from 400 600 800 1000 grit. Then went straight to the stitched cotton buffing wheel drill attachment. The finer cutting compound was enough ( I think because I went right up to the 1000 wet and dry)

- Came out really good, I should post some pics up.

I would never ever attempt this again, unless paid an insane amount of money.

Iv heard ppl do a little each night in front of the TV, with it on their lap, but I prefer doing it wet, the paper lasts a lot longer and doesn’t clog.

Get some pics up Michael

[18RZZ]

Anyone want to polish some pipes for me, or got any good suggestions? They already have a polished finish but they're old. I tried cleaning it with household cleaner (Mr. Muscle etc.) to get the grime off then used normal polish and elbow grease but still looks just as crappy, but slightly cleaner .

i would like to mate but its a long way from queensland, try to use a compound called autosol should be able to get it from most auto store. apply compound to surface with finger and work in until all the compound turns black then use a rag in the same motion this will remove most of the residue finally use a clean rag over the surface again and this will remove remaining compound.

this is a cheap fix and will not take out any deep scores or scratches but will improve the shine of the part.

[18RZZ]

CRAVED: so how do you know when more compound is required on the buffing wheel?

with a course compound I.E. fast cut ( grey ) brown rouge ( brown ) apply till mop is completely coated on parant surface. the best way to tell is when you are barrelling ( polishing ) pull the job against the direction of mop this will apply the compound to the job and after this run over the same spot this will rooll over the metal and help with a better shine. applying cutting compound is simple on your backward stroke if very little or no compound is released from mop then it is time to reapply.

However with a green chrome compound less is more the more you put on the mop the more you have to get off allt he green is for is to take of the brown or grey coating giving you the mirror finish you want.

( P.S. in my expierience the white compound is to fine for metal and i only use it to polish plastics. but i do have acces to the green chrome. so if it works go with it. )