Rubbing out scratches

Includes sheet metal, rubbers, bumpers, badges and rust repairs.

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careyman
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Rubbing out scratches

Post by careyman »

Hi guys, might seem stupid simple problem but im working around my ute getting rid of imperfections like this...

Image

now... do i just keep rubbing till its gone or whats a good product to fill the voids so it can b rubbed back?? Im worried im gona have low spots where ive gone deeper in some areas to remove them :?
cheers
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rosco
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Post by rosco »

Hi Careyman,
by the look of that photograph, I doubt very much you'll avoid a "low" if you block down to the depth of those nicks....

My suggestion would be to use a "fine" plastic filler - K&H make a product called "pedigree gold" - it is extremely fine and very easy sanding.
You will need to prime it again before your top coats.

My suggestion would also to use a "guide coat" once you have filled and primed again - this should give you some indication of any "lows" in the area.

Others may suggest using a "spot putty" - this basically is very thick paint.... personally, I have not ever had success with this - and have found that in time - it shrinks.... to me, it is the same as not leaving heavy coats of primer long enough to "pull down".....
The other risk I have found with spot putty (or building up with many, many layers of primer/filler) - is that if you apply a "wet" top coat - you may very well see the "scratches" show through and leave low spots where the original scratches were... then you're back to filling again etc...
The same can be said for plastic fillers - top coats will not penetrate through them - this amounts to "wet" patches in the top coat when you spray a moderate to thick coat on ..... the thinners in them will penetrate the thinners around them - but not the plastic....
However - I believe this is a better alternative to having the original scratches re-appear - this is known as sand scratch swelling....

Sorry for the novel, Careyman....

happy to answer any q's .....

frats,
Rosco
rosco
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Post by rosco »

Sorry, forgot - just a bit of "also".....

When you "work" your panel - I would also suggest using a very hard but slightly flexible pad to block back with.... whatever you do, don't use your fingers.... you'll drive yourself crazy trying to get a straight surface with follows the original...

I do not recommend using a soft pad either - as it will tend to sand away where the pressure points form.

A very stiff pad, which will just bend to the shape of the panel - will more than reward you with a straight blocking down - especially if you use a guide coat to indicate when the surface is level....

If you are working a panel which "is" absolutely flat - I would recommend using a large flat rubbing board - these are made of plastic/metal and a half sheet of paper is clamped at each end.
I have two of these - one with a very thin layer of foam rubber - the other with just a hint of foam rubber - enough to grip the paper.

I have also fabricated some smaller rubbing blocks using various thicknesses and sizes of firm rubber - these, I use for difficult areas.

For concave curves, I use varying thicknesses of wood dowelling - and adhere some rubber around them with Sikaflex.... I find these the best for keeping channels (like between the fins and luggage compartment lid etc) in a straight line without any "gouges"....

Careyman - I forgot to ask.... I expect we are dealing with acrylic here?... I hope so - I have no experience with 2K and precious little with enamel....

frats,
Rosco
EK JAY
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Post by EK JAY »

Hi :)
I would smear a light coat of light weight body filler
over those then sand with a block
then a couple of light coats of primer filler then let it dry
for a week at least
it will also shrink some aswell in that week then sand and check
again if not perfect repeat primmer filler process
its the joy's of body work takes time and patience but worth it in the
end . :) Jay
EK JAY SINCE 1990
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careyman
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Post by careyman »

Thx guys, awesome responses, I didn't even think of shrinkage. I happened to find a can of primmer filler today too. Ill go back (was just at autobarn :roll: ) and grab some of that "pedigree gold" and have a tinker tonight.
Hey, the guide coat u mentioned is this just a coat of primer or does it need a special type or paint to see the flaws?I've seen forum members mention it plenty of times and am not quite up to speed on it (yet)
Cheers guys :wink: colour
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rosco
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Post by rosco »

Hi again, Careyman.....

ummmm.... you might have to chase pedigree gold up - it is a K&H product and as such - if you find K&H products on the shelf they should be able to get it in for you....
The reason I like it, is that it is the finest plastic filler I have used and sands very easily..... yet still retains quite some strength - well beyond that of acrylic paint in the surrounding area.

I would suggest it be used "instead of putties" - as a "light" fill.... anything deeper or requiring reinforcement should be treated with some of the "heavier" and more "flexible" fillers - most serious case after panel beating would be the reo-fills... I like the Moto-spray reo-fill with stainless particles.... but this is my choice - not necessarily that of many others.
I use the Moto-spray fine filler next - then finish off with K&H "pedrgree gold"..... then I use a 1K etch, primer/surfacer, guide coats as necessary and finally - when just one or two rubs is necessary to remove the "mist" guide coat - I then begin the top-coating process....
This is my procedure - and I must state heavily here - I by no means get "show" results..... but am comfortable with the level I reach.....

Guide coat - no - not acrylic... the stuff I use is Dexone - it is also known as GMH black - it is a sort of cellulose quick drying enamel ..... but of course - you are going to remove it all.... prior to further coats.
The stuff you need will dry readily so that you can start blocking back within 10 mins or so... when you come to spraying it on - just a "mist".... just barely visible enough for you to work on with your sanding block...... don't be tempted to go for the "rat" look - you have to sand it all off regardless - you certainly don't want more work... do you?

Ummmm... it's not necessary - but once you learn to use it - your top coat results will bring all the additional work to show on your face..... yes, an extra step - but a great assistant when you are trying to get panels ripple free..... try looking "along" some panels on so called "show cars".... if they've done their stuff correctly - you should be able to "focus" on a reflected object beyond the finish and follow it along a panel...... any imperfections will show up as the object changes shape (or location)....

fire away, don't mind helping with this subject at all.......

frats,
Rosco
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careyman
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update

Post by careyman »

Covered with primer filler (to b rubbed back a final time) before putting a light coat of prime to be ready for paint.

Image


next problem,,, what do you fellas reccon about getting to the rust under this support bar on the inside of the roof?

Image

:wink: Cheers
FB's=Friggin Bewdyful
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