Cleaning and smoothing aluminium prior to polishing

[pkr]

I'm in the process of cleaning and smoothing this lump of aluminium prior to polishing it.

The full length ribbed parts are not a problem as I'm wrapping sandpaper around a flat piece of steel and sanding back and forth along the ribbing. It's not there yet but good progress is being made at the top.

There are three problems I need to resolve :

1. How to efficiently sand and clean the shorter runs of ribbing between the dummy spark plug caps.
2. How to sand the flat areas around the text, the central part of some of the text ( the '6', 'A', 'P' etc ) and the edges of the text.
3. How to clean and smooth the cuircular recesses for the fixing screws.

I have considered spraying it black and then just polishing the surface, but I'd prefer the fully polished look if possible. As a compromise, I would paint the background and edges of the text.

Can anyone make any suggestions on how this can be done.

Thanks.

 

[brightspark]

u could get it beadblasted then loads of elobow grease with wet and dry paper and a polishing kit http://www.metalpolishingsupplies.c...ishing-Kits/?gclid=CLypxfnuka8CFWohtAodLwiEzw

 

[triumph]

hi maybe u could try some dremmel attachments they can be quite effective though the cheaper ones ie polishing mops dont last . p600 wet dry on a thin bit of plastic may help rubbed between the grooves not an easy job, did my bike takes alot of time on detail work , a device called a loy block can also help remove marks in alloy but keep the grit block away from the engine. all the best c

 

[Fazed]

Dremel with a brass wire wheel?

 

[Lawnmowerboy]

bead blast then DA with wet and dry then a polishimg mop and appropriate soap?

 

[hareng]

Nothings going to get in to the A and such like, be there all year with a dremmel.

Not fond of mop polished it could be done but what degree of rounding off all edges!
Would the Alfa last longer than it would take you to polish

Wrap silicon carbide paper round an assortment of profiles or even cork block.

Me i would paint it Alfa colours and knock the tops off.

 

[hotrodder]

I'd pay someone else to do it if it has to be properly shiney all over. Or as said, polish the easy bits and paint the rest.

It'd still probably be soul destroying but pre-polishing abrasives like satene may be the way forward if it's 'straight' but just a bit manky... http://www.thepolishingshop.co.uk/acatalog/Abrasive_Compound_.html You can also buy as abrasive powders and glue for coating felt points and the like

 

[Paul G]

I cleaned my cam covers with a bristle brush (wooden nail brush) and thinners to get the muck off, then sprayed the whole thing.

I then took the paint off the high spots with a sanding block and wet & dry.
For smaller bars use a smaller block. I would never use a curved or round tool on a flat area.

Cheers,
Paul G

 

[tigler]

Personally, I'm not a fan of polishing engine covers, they corrode like bar steward at the first sign of moisture !
Heat dissipation is also substantially reduced. Paint with polished highlights is a much better idea IMHO.

 

[pkr]

Thanks all for input so far. I will read properly later - I'm tied up at the moment beating the forthcoming hosepipe ban! But not being irresponsible about it.

Text : the plan is to paint that so I will be avoiding that with the mop. But a good tip in respect of rounding off the edges.
Heat dissipation : that top bit doesn't get hot as it's only the cover to the coil packs. There is another bit that is the true cam cover but only a part of that is exposed and will be polished, the rest will stay au naturel. Even that bit doesn't normally get very hot ( there's a rubber seal around it's periphery where it meets the head which must insulate it a lot ). Moisture/corrosion is a good point but I seem to recall reading about sealers that would inhibit that.

Looking forward to reading the rest later and following those links.

Thanks again.

 

[RichardM]

Personally, I'd give it a good going over with a brass brush to get the muck off the casting without ruining the existing "polished surface". Then re-polish the tops, spray with engine enamel and clean the paint off the polished surfaces with acetone.

Alternatively send it there:

http://www.aloh.co.uk/samples/

 

[Wedg1e]

I'm guessing the areas inbetween the ribs, lettering etc. are as-cast, ie rough as a badger's nadgers.
You'll be needing shares in Autosol, Loyblox and wet'n'dry before that's smooth

 

[langy]

If you really want to polish between the fins you would use a thin felt wheel mounted with abrasive and abrasive points for the corners, its a lot of work !!!
Personally i prefer to pre polish the surface and leave the bottom of the fins painted as a nice contrast.
You don't need to sand the surface after if you pre polish before painting, as each coat goes on just carefully wipe the surface with a thinners paper towel.

Heres an example

 

[mangocrazy]

Top work there, Langy - as I'm sure you've been told many, many times before...

 

[langy]

Top work there, Langy - as I'm sure you've been told many, many times before...

Thank you, by using a thinners rag to wipe it gives you a smoother transition from polished to the painted edge