Finer points of Aluminium polishing. A Guru's help needed..

[lrh]

Re: Finer points of Aluminium polishing. A Guru's help neede

When you see this you need to go back to a coarser grit and make sure you don't leave any deep grooves... Easier said than done, it can be very hard to see or feel before you move on.

Seems a waste to ruin your finer-grit polishing but moving to a finer grits will make it stand out more and more.

 

[firedfromthecircus]

One tip I have found quite handy when wet sanding is to always use the next grade of paper at 90 degrees from the last. This way you know that you have removed all the marks from the previous grade because all marks are in the same direction. It means you don't oversand as you move to the next grade as soon as all the marks from the last grade are gone.

Not sure I have explained that very well, but it works in practice.

 

[saulus]

Hello,

Thanks for all your replies!!

There's some good advice there.

@klasse/Vinya77/Rampage/Tech1210: Been a bit reluctant to use tools as I would end up spending more money on kit & feel caution regarding damage too but there's a fair few of you saying it's AOK tho..If I'm going to have to reautosol / resand again & again though then the purchase seems altogether more appealing I will just make sure I go careful with something that isn't going to warm the ally up or bore holes through it :shock:
I reckon some 3m or Mirka Abralon foam backed pads wouldn't go amiss right now though for the welds, nooks & crannies.

@Irh: Cheers for the specific advice about my photo. I will go to a coarser grit to get rid.. I understand the point you make about just making the scratches stand out more if I go onto a coarser grit. I'm tuning me 'eye' in as to when I feel when the paper should change

@WD Pro: Nice lump of info there. I read a fair bit of that before I started the frame & realised what I was getting into regarding input/time needed. I think those ROOX barends are where it's at!!

@GT Steve: Keeping the paper wet?..Yes, I tend to let it run dry as it feels like it's doing more to the metal. It feels like it's just gliding over the metal when it's wet!..and I can see what's happening to the scratches I'm trying to rub out when its just dust- bad habit then :roll: Bad idea having alu dust flying about as it's neurotoxic too. Re autosolling/resanding- didn't think that might happen- makes me reconsider a mechanical sand/polish. Can you recommend a good sealing wax??

@firedfromthecircus: re: 90deg rub: I've been trying that technique on the larger isolated scratches to get them out quicker and to prevent 'scalloping' of the metal -where you create a sunken area where you have rubbed too hard basically.

@ Klasse: I resorted to using steel wire wool to get powder coat off some Alu forks I did a while back, nothing else was tough enough, although I was using rubbish paintstripper to be fair. The powder coat was a total and utter B*****D to get off but then I went to W&D paper to lift the steel particles off from the Alu after I read about steel wool rusting in the alu if you dont get rid of it :shock:

I have taken photos of this frame "before / during and after" and all that. There'll be a thread about this bike.

Cheers for the feedback guys

 

[vinnya77]

This is my attempt.

Taken off the laquer with the first wheel and compound.
Just started with the second as you can see in the middle.
Will then finished on the third.

A bargain for less than £15 delivered.

 

[lewis1641]

I have quite a lot of experience with polishing alloy wheels. I start with as lighter grit as I van get away with, usually 800 if I have used print stripper or much coarser if I have to remove laquer.

As mentioned above I alternate the direction of the paper till I get to 1000 grit. At that point I run in the same plane (along the tube if it were a bike)

I usually sand up to 2000 grit then move onto mops and compound. Then onto a dedicated alloy polish (maguires nxt)

Using mops and compound is much more effective that standing then autosol, I have never had a good result this way.

There are shortcuts to be had too but really you need a bit of experience

 

[saulus]

Alright, Alright! Point taken Mops/Compound give a stunning look.. it appeals from a time/ elbow grease perspective too but what sort of budget do I need for compound;mop; etc? I have a standard domestic drill for starters.


@Vinnya: That'd be nice if I can get that kind of result. Stupid Question though: Clarify, What's the "bargain for less than £15 delivered" ? That what you got the frame for or the price for polishing odds and ends?

Cheers

 

[vinnya77]

The polishing kit was less than £15 delivered.
It included the drill attachment.
3 different heads
3 different compounds
And a bag of small heads for awkward places

I didn't have to buy anything or pay anyone to remove the lacquer.
The course wheel done that.
My other frame I thought I got done cheap.
Cost me £10 to blast, £25 powdercoat, £20 to lacquer.
This one will cost £15 for the kit, £20 to lacquer again.
Plus will look so much better.
Just cost me the time to polish.

It's up to you, just trying to help.

 

[vinnya77]

Oops. Silly phone. Double post

 

[saulus]

The polishing kit was less than £15 delivered.
It included the drill attachment.
3 different heads
3 different compounds
And a bag of small heads for awkward places

I didn't have to buy anything or pay anyone to remove the lacquer.
The course wheel done that.
My other frame I thought I got done cheap.
Cost me £10 to blast, £25 powdercoat, £20 to lacquer.
This one will cost £15 for the kit, £20 to lacquer again.
Plus will look so much better.
Just cost me the time to polish.

It's up to you, just trying to help.

I've been looking at polishing kits today .. after adding up total costs for paper grades its worth the extra few quid, quickness & quality of finish to get a kit you describe above. I'm glad I asked at this early stage. I just assumed hand polishing would be a ot cheaper and focussed on that type of advice..

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