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PostPosted: Fri Aug 09, 2013 2:51 am 
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Can anyone tell me if/how you can distinguish a paint job on a frame or if it's been powdercoated?


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PostPosted: Fri Aug 09, 2013 1:21 pm 
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I'ts not easy, but....


Powdercoat is typically the same thickness all over. Spray cellulose etc..is often 'thinned' out by the operative near corners, cable stops and extremities to avoid runs and thickening.

Depending on colour/finish, powdercoat has a certain texture that is similar to floor screed or self-levelling compound for flooring. It looks flat but on closer inspection there is a certain ripple. Sometimes. Built up finishes like spray on paint achieves a flatter almost glass-like finish.

If the paint you see is real fancy. fade, pearled or GT-like splatter then, it will most likely be spray on.


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PostPosted: Fri Aug 09, 2013 1:42 pm 
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No undercoat or primer with powder coat, so if there are any chips or scratches you should be able to see that it's all one colour down to the bare metal. But as Marc says, powder coat generally looks slightly thicker, more "plastic-y", but it does vary and there are several different types of powder coat: polyester, polyurethane, epoxy etc. and I imagine that they might have slightly different finishes.


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PostPosted: Fri Aug 09, 2013 2:24 pm 
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As above, different powder processes and even different operators using the same process can yield completely different results ...

I recently stripped these :

Image

But this is also powder (straight from the gun) :

Image

Bad orange peel is not always present in a powder finish :

Image

If it is, it can be flatted out and polished ...

The last two images also have a beige primer underneath so that doesn't help you either ...

Hit it with a hammer and see if it chips ? Oh, hang about a min ... :lol:

Metalic colours ? Powder can do those ...

Fades ? Powder can do those to ...

A crap powder job looks crap.

A good powder job can look like paint.

Good luck !

WD :D


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PostPosted: Fri Aug 09, 2013 6:28 pm 
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Joined: Tue Oct 09, 2007 1:55 pm
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A lot of later Konas (certainly 1998 on) were powdercoated white with a colour lacquer seemingly wet sprayed over the top. I guess that this was to allow production flexibility. So a white base layer can still be powder. Complicated.

I guess the best guide is that if it has loads of chips it isn't powder!


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PostPosted: Fri Aug 09, 2013 7:05 pm 
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okay i'm trying to determine how to strip the finish off a 1993 Brodie Sovereign and an unknown year Gator Blade fork. i've sanded down some of the areas were there was signs of rust to determine if it's only surface rust. i don't fancy sanding down the entire frame/fork so i'd like to know if it's paint or powdercoated to do a chemically strip.

any thoughts/opinions given the following images?

my Brodie thread is here: viewtopic.php?f=6&t=263251


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PostPosted: Fri Aug 09, 2013 7:14 pm 
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My gut feeling = paint.

Based on the chips in the top left of the first picture.

WD :D


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PostPosted: Sat Aug 10, 2013 7:47 pm 
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Ditto based on that fork chip


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PostPosted: Tue Aug 13, 2013 1:32 am 
Dirt Disciple

Joined: Wed Aug 07, 2013 6:02 pm
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Location: Peter bog horror UK
Personally I would'nt sand down the paint, It can leave flat or uneven spots from trying to overwork more corroded areas. Plus its almost impossible to remove dirt, rust or oxidation in all the nooks and crannies and lets not forget the pitting that rust can hide in. Ive got the badge, balloon and swirly hat from learning the more costly and time consuming way with unsatisfactory results.

Get it blasted, It will get rid of all the crap off the frame evenly, but only either bead or a very fine shot blast otherwise the finish will be affected with a more coarse blast. personally I have just sent my Kona frame off to be blasted and powder coated for the princely sum of £35. If your'e unsure, my Lava Dome frame will be back next week and posted on retrobike with the results if your interested?


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PostPosted: Tue Aug 13, 2013 1:47 am 
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Acetone will remove powdercoat but will do nothing to paint. ;)


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