Removing surface scratches on a black gloss Alembic

[clarkybass]

Hi I mentioned this in another thread but thought it would be better dealt with as a thread of its own. I have an '88 Spoiler in gloss black and there are a fair few surface scratches on my bass above the playing area (I presume a previous owner wore a metal watch band on his right wrist). I wondered if there's a way of removing or reducing these? To be clear, none are deep but there are so many it's slightly matte on that part of the bass. I don't want to pay for a re-fin as most of the body is in good condition so any cheap, quick fixes but would be welcome (T-cut? car polish, as suggested by an Alembic Club-ite? anything else?)
 
Thanks, as ever, for your thoughts

[adriaan]

In the FAQ section, under , you'll find a wealth of information.

[clarkybass]

Thanks, I did check there before posting but couldn't find anything relevant to my specific enquiry. The Finish Care section talks about polishing and general care but does not address repairing/restoring minor finish problems such as mine.

[terryc]

Try T-Cut or a fine cutting paste suitable for plastic car bumpers etc.
Don't rub back and forth but in a circular motion.
It takes some time

[clarkybass]

Thanks terryc. Very helpful. I will get to work this weekend!

[adriaan]

Might try that myself too, thanks!

[terryc]

Glad to help and best of luck with restoration
You should do pics of before and after the process

[crobbins]

Here's a link to Stew-Mac.
 
http://www.stewmac.com/shop/Finishing_supplies/Abrasives,_polishes,_buffers/ColorTone_Polishing_Compounds.html

[clarkybass]

Unfortunately I didn't get to a shop selling T-cut at weekend. I am in UK so StewMac not an option but I wondered if this Fender restoration kit would do the trick? http://www.stringsdirect.co.uk/products/884-fender_meguiars_instrument_care_kit Has anyone tried this - it says it can remove fine scratches

[terryc]

clarky...well for the money it may do the trick but these will be products with there own name on them.
I have used Auto Glym products in the past as well stuff from Halfords, the key is the fine cutting pastes and circular polishing motion.
You could use it with a rotary polishing attachment on a hand drill don't be over zealous as it could cut deeper than you want.

[dfung60]

The polyester finish on your Alembic is similar to automotive paint but harder (which allows it to maintain a more mirror-like finish).  You can use auto polishes to fix the problems; go to a automotive paint shop to get the best quality stuff.
 
To create a finish with a mirror gloss, you need to have a level and totally smooth surface at a microscopic level.  When the finish was originally sprayed on the surface is pretty smooth but not particularly level.  You start with a fairly coarse abrasive which cuts through the finish and levels the surface, but leaves big scratches.  After the surface is level, you switch to progressively finer polishes which remove the scratches from the previous abrasive until it's smooth as a mirror.
 
In your case, handling has created scratches in the surface.  You'll start with a fairly coarse abrasive and polish out those scratches.  If you can feel roughness with your thumbnail going across the scratches, then you need something really rough like rubbing compound. If the surface is matte but feels smooth, then a white polishing compound may be sufficient.  You want to use the least abrasive compound that will do the job, since each pass will remove some of the finish. If you use too fine of an abrasive, it'll take forever to get the deep scratches out and you'll never completely remove the marks.  Take your bass to the auto paint shop and they can set you up with exactly the right abrasives (they probably have 4 grades of sandpaper that are smoother than glossy paper!).
 
A progression of 3-4 abrasives will probably get you completely back  to the original appearance.
 
Although there's been some different advice here, you normally want to work with linear strokes when doing this kind of polishing.  The reason for this is that it's hard to fully remove the deep scratches from the coarser abrasives if they're circular.  Using a rough abrasive with a circular buffer is the cause of swirl marks on cars, which you don't want.
 
Black finishes are the hardest to maintain as they show imperfections the most.
 
David Fung

[gtrguy]

I'd try 800 wet sand paper soaked overnight, lightly, with a backing, and then switch rapidly to 1000 to 1500 to 2000 (all soaked overnight). Then a high quality swirl mark remover, by hand with a cotton tee shirt type cloth to bring up the gloss again, and then a good carnuba wax. Watch how it's going and do not sand through the edges.  
 
Unless you have a very big buffing wheel!
 
Dave