Monday, 30 September 2002 17:00

Replacing door skins for fun and profit

Written by Toby Chess

Replacing a door skin? If you are a shop owner, does that process bring fear to you? On the contrary, this process should be a fast, profitable repair. There are a couple of techniques and some special tools that can be used to speed up the process, but let's first look at the estimating process. 

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 Chess

If you just go by the included items from your estimating system, the dollars could be flying right by and you won't even know it.

Remove glass before welding

First, you should R&I the glass if you are performing any welding operations (not an included item in Mitchell and CCC, but included in ADP). If you were replacing a door skin on a late model Chevy Camaro, the R&I of the door glass and mirror could add 1.2 to 1.5 additional labor hours to your estimate. Attached moldings, including the belt molding, must be removed and are usually not an included item. How about door mirrors? Nameplates and ornaments?

And what about all the items for corrosion protection? Again, none of these items are included in the repair times. You need to look at the door and the repair process and see what corrosion items are needed on an individual basis. You might need weld-thru-primer, sealants, gravel guard, adhesives (to glue skin to the intrusion beam), foams, self-etch/epoxy primer, and cavity wax. Each of these items should be an individual line item on your estimate because each door is an entity in itself. For example, not every door has a gravel guard. And for heavens sake, please don't lump everything into the term "replace corrosion protection." Another "not included" item is a sound-deadening pad as is the piece of plastic (moisture barrier) between the trim panel and the door shell.

Techniques and specialized tools
 
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Checklist for door skin repair
 

We made up this list as we replaced the skin on a 1999 Toyota Land Cruiser.

  • Remove door from vehicle and remove all attached parts including the door glass (to prevent glass from breaking and/or being pitted by the welding sparks).
  • Note position of sectioning positions of window openings.
  • Remove/cut/drill spot welds and/or brazing.
  • Grind off hemming flange with a grinder and be careful not to damage the door flange.
  • Remove the door skin.
  • Remove all old sealant/foam/adhesives from door flange and intrusion beam.
  • Repair any damage to door flange.
  • Prep the door flange for welding (be careful not grind off too much).
  • Apply weld thru primer to mating surfaces that are to be welded.
  • Restore corrosion primer to any exposed bare metal.
  • Cut and test fit new door skin.
  • Apply sealants, adhesives and/or foam to the intrusion beam.
  • Position the new door skin to the frame (partially hem the door skin).
  • Reinstall the door and check the fit of the door. Adjust accordingly and remove again for the final repairs.
  • Weld the new door skin to the frame.
  • Finish hemming the door skin.
  • Dress all welded areas; apply seam sealers and corrosion protection primers.
  • Apply gravel guard (if applicable) and install sound deadening pads.
  • Refinish interior door jambs.
  • Re-install door to body.
  • Refinish door exterior.
  • Apply cavity wax to interior of door.
  • Reassemble door.
My good friend, Tony Passwater, taught me a great trick. Take 80 grit sandpaper on a grinder or DA sander and chamfer the outside flange of the door skin. By performing this operation, the lip will fold over much easier and you will have very little damage to the door edge if any. I had a technician who beat the edge over so badly that he had to put body filler on the entire edge of the new skin. What a waste of time and materials!
 

Did you know that there is a special hammer for door skins? It has a curvature for hard to reach areas and the other side of the hammer is reduced at the end to put all of its energy on the flange. There are two great dollies on the market that prevent the outer skin from being damaged. The first one is made of a hard rubber compound and the second is a "bean bag" (leather covered and filled with lead shot). These two dollies can be used in place of a traditional hammer and dolly and will reduce the amount of damage to the new skin as you hem it.

Another tool that speeds up the repair process is a pneumatic caulking gun. Besides being faster, it produces an OEM like finish. Finally, the price of a resistance spot welder has dropped the last couple of years to where they have become very affordable. They have three benefits over the traditional plug welds. First, they produce an OEM type of finish. Second, they are faster, and lastly there is no clean up of the weld nuggets as there is with MIG welders.

Toby Chess is a frequent presenter and lecturer at NACE and CIC meetings. He has over 25 years of experience in auto body repair.

 


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