Stripping paint

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(Chemical paint strippers=)
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Same as hood. Tie weight to the latch to keep the trunk from rising, or tape with the same three layers and close the deck tightly -- the three layers of masking paper at the back edge of the deck and push the mess onto the paper then pull the layer off and throw in trash.
 
Same as hood. Tie weight to the latch to keep the trunk from rising, or tape with the same three layers and close the deck tightly -- the three layers of masking paper at the back edge of the deck and push the mess onto the paper then pull the layer off and throw in trash.
  
===Chemical paint strippers===
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====Chemical paint strippers====
 
*Aircraft stripper (blue can)
 
*Aircraft stripper (blue can)
 
*XXX paint stripper (black can with red X's)
 
*XXX paint stripper (black can with red X's)
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There are instances where using a 4" flooring razor blade scraper or smaller razor scrapers made for body and paint work will be the quickest way to remove a layer of paint. However, if the paint has properly adhered to the primer, using the blade might not be possible. Once paint has been removed, you may want to remove the rest of primer and areas of paint that were not possible to remove with the blade .
 
There are instances where using a 4" flooring razor blade scraper or smaller razor scrapers made for body and paint work will be the quickest way to remove a layer of paint. However, if the paint has properly adhered to the primer, using the blade might not be possible. Once paint has been removed, you may want to remove the rest of primer and areas of paint that were not possible to remove with the blade .
  
Never start off with a used blade -- nicks will scratch deeply in the metal. As soon as you get a dig, change the blade. Try using straight back blades for body work -- if the ends of the blade are rounded (slightly) from use it will keep you from gouging the metal. An excellent way to start is by rubbing the new blade quickly back and forth over glass like you're trying to scrape off overspray; this removes small burrs in new blades
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*Never start off with a used blade -- nicks will scratch deeply in the metal. As soon as you get a dig, change the blade.
 
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*Try using straight back blades for body work.
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*If the ends of the blade are rounded (slightly) from use it will keep you from gouging the metal. An excellent way to start is by rubbing the new blade quickly back and forth over glass like you're trying to scrape off overspray; this removes small burrs in new blades. To lessen any further risk of gouging, run the blade backwards against old smooth paint 4-5 times. This will push up the burr and permit the blade's edge to glide much more easily.
 
*You will have to pay attention to the way the body curves.
 
*You will have to pay attention to the way the body curves.
 
*Use two hands and steady amount of pressure & the paint will fly off in tiny little chips.
 
*Use two hands and steady amount of pressure & the paint will fly off in tiny little chips.
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*It seems that if you try not to take too big of a bite and try to make b "C" shapes or curves, it lets the paint come off easier.
 
*It seems that if you try not to take too big of a bite and try to make b "C" shapes or curves, it lets the paint come off easier.
 
*You will need to use both sides of the blade by switching sides often. This keeps the blade from getting too dull to get under the paint.
 
*You will need to use both sides of the blade by switching sides often. This keeps the blade from getting too dull to get under the paint.
 
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*Gloves, eye protection, and dust mask are mandatory. Little slivers of paint will go everywhere. A shop-vac while working is great for the cleanup.
Keep in mind this method is only used for extremely thick or old paint that is already peeling off.
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*You may find that a conventional razor blade holder is difficult to use for stripping paint. The flakes tend to bunch up between the blade and the tool. To solve this problem, us a regular vise grip to hold the razor blade. Turn the vise grip upside down for a less dramatic angle of attack. Too sharp an attack might cause the blade to catch, which could gouge the sheet metal.  
 
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Gloves ,Eye protection & a dust mask are mandatory.
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little slivers of paint will go everywhere. a shop vac while working is great for the clean up.
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[http://www.hotrodders.com/forum/subscription.php?do=viewsubscription&folderid=all]
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--[[User:Slowride66|Slowride66]] 19:12, 9 May 2008 (PDT)
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(See [[Stripping paint#Orbital sander|Orbital sander]] below).
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You may find that a conventional razor blade holder is difficult to use for stripping paint. The flakes tend to bunch up between the blade and the tool. To solve this problem, us a regular vise grip to hold the razor blade. Turn the vise grip upside down for a less dramatic angle of attack. Too sharp an attack might cause the blade to catch, which could gouge the sheet metal.
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To lessen any further risk of gouging, run the blade backwards against old smooth paint 4-5 times. This will push up the burr and permit the blade's edge to glide much more easily.
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====Homemade scraping tool====
 
====Homemade scraping tool====
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====Media blasting====
 
====Media blasting====
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See [[Media blasting]].
  
 
Blasting with media that removes rust is one way to ensure the rust is removed from the bottom of the pits.  Contrary to what the advertising would tell you, most chemical methods do not fully remove the rust from the bottom of a pit.  Sanding to the bottom of a pit is likely to warp the panel through heat and the fact you are making the metal thinner.
 
Blasting with media that removes rust is one way to ensure the rust is removed from the bottom of the pits.  Contrary to what the advertising would tell you, most chemical methods do not fully remove the rust from the bottom of a pit.  Sanding to the bottom of a pit is likely to warp the panel through heat and the fact you are making the metal thinner.
  
Warpage of the metal is a common worry, but no an issue if one understands how and why the metal warps.  The metal warps because of expansion of the surface of the metal from the impact of particles.  A small amount of impact will not cause enough damage to do anything more then make the surface a little bit rough.  When the media is given enough energy through speed or density (faster or heavier hammers) then you will get the surface expansion that causes warpage.   
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Warpage of the metal is a common worry, but not an issue if one understands how and why the metal warps.  The metal warps because of expansion of the surface of the metal from the impact of particles -- impingement.  A small amount of impact will not cause enough damage to do anything more then make the surface a little bit rough.  When the media is given enough energy through speed or density (faster or heavier hammers) then you will get the surface expansion that causes warpage.   
  
To blast safely you need to run a low pressure and limit the amount of media in the stream of air. This will mean a much slower removal of material, but no chance of panel damage. One setting that has worked is 40 PSI on the pressure pot blaster and open the media valve just enough to see the sand mixing in the air. This setting will not damage the metal even with prolonged working in one area.
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To blast safely you need to run a low pressure and limit the amount of media in the stream of air. This will mean a much slower removal of material, but no chance of panel damage. One setting that has worked is 40 PSI on the pressure pot blaster and open the media valve just enough to see the sand mixing in the air. This setting will not damage the metal even with prolonged working in one area.
  
The siphon blasters are more likely to cause warpage. This is because you can not easily regulate the amount of media in the stream.
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The siphon blasters are more likely to cause warpage. This is because you can not easily regulate the amount of media in the stream.
  
Keep in mind more significant more panel warpage is done while trying to repair a panel.
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Keep in mind more significant more panel warpage is done while trying to repair a panel. See [[Sandblasting]].
 
   
 
   
See [[Media blasting]]
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====Soda blasting====
 
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See [[Soda blasting]].
Soda Blasting has become popular recently.  This method uses Baking Soda, and is very effective as it will not damage the glass, plastics, chrome and rubber on the vehicle when used properly.  This means that a car can be stripped with all of the parts still attached (if you wanted). Another method of of blasting that can be useful is plastic media blasting it is cheaper than soda blasting and can be used in the same instances, but special care is needed.  Soda blasting does not remove rust.
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====Sanding====
 
====Sanding====
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See [[Sanding]].
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Always use a respirator when using sanding tools.
 
Always use a respirator when using sanding tools.
  
 
Removing paint from a panel using a random orbit sander is the least messy way of stripping paint from large panel. Use 40 grit sandpaper for the quickest job.
 
Removing paint from a panel using a random orbit sander is the least messy way of stripping paint from large panel. Use 40 grit sandpaper for the quickest job.
  
After sanding off all traces of paint and primer,sand the surface smooth with 80g on the random orbital sander to smooth out 40g sand scratches as they will show though the finish, remove dust with a blow gun and a clean cloth. Don't touch the metal with your skin; it will contaminate it. Immediately spray on etching primer to keep ambient moisture from contaminating the panel. Always wear a respirator when spraying etching primer.
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After sanding off all traces of paint and primer, sand the surface smooth with 80 grit on the random orbital sander to smooth out 40 grit sand scratches, as they will show though the finish. Remove dust with a blow gun and a clean cloth. Don't touch the metal with your skin; it will contaminate it. Immediately spray on etching primer to keep ambient moisture from contaminating the panel. Always wear a respirator when spraying etching primer.
  
 
=====Orbital sander safety=====
 
=====Orbital sander safety=====
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Bear in mind that paints on cars may contain lead.
 
Bear in mind that paints on cars may contain lead.
  
====Wire Cup Brush====
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====Wire cup brush====
A wire cup brush will take paint off rapidly, almost as fast as 40 grit sandpaper on an orbital sander, when the wheel is mounded on an angle grinder. The wire wheel will not scratch the metal as deeply as the sandpaper, making prepping for primer a bit easier.
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A wire cup brush will take paint off rapidly, almost as fast as 40 grit sandpaper on an orbital sander, when the wheel is mounted on an angle grinder. The wire wheel will not scratch the metal as deeply as the sandpaper, making prepping for primer a bit easier.
  
 
Wire cup brushes come in two basic types - with kinked wires, and with twisted (or knotted) wires. Although it seems like the twisted wire would be faster, as it is more agressive, the kinked wire actually will strip faster, as it is more flexible and can make contact with a larger area of the panel with every pass of the tool.
 
Wire cup brushes come in two basic types - with kinked wires, and with twisted (or knotted) wires. Although it seems like the twisted wire would be faster, as it is more agressive, the kinked wire actually will strip faster, as it is more flexible and can make contact with a larger area of the panel with every pass of the tool.
  
 
Wires will come loose and fly off the wheel during use. It is recommended to wear a face shield and thick clothing when working with one to avoid injury.
 
Wires will come loose and fly off the wheel during use. It is recommended to wear a face shield and thick clothing when working with one to avoid injury.
 
  
 
===Other methods===
 
===Other methods===
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[[Category:Body and exterior]]
 
[[Category:Body and exterior]]
 
 
But it '''is''' '''recommended''' to use a wire wheel(knotted or crimped) on an angle grinder.  I have used this exclusively for stripping four layers of paint off my 57 Chevy Pick up.
 

Revision as of 14:28, 2 September 2009

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