Paint repair - Revision history

Al at 08:25, 2 March 2008

2008-03-02T08:25:58Z

Al at 08:21, 2 March 2008

2008-03-02T08:21:08Z

Al at 23:51, 1 March 2008

2008-03-01T23:51:39Z

Al at 12:18, 1 March 2008

2008-03-01T12:18:54Z

Al at 12:12, 1 March 2008

2008-03-01T12:12:37Z

Al at 12:11, 1 March 2008

2008-03-01T12:11:43Z

Al at 12:10, 1 March 2008

2008-03-01T12:10:07Z

Al at 12:04, 1 March 2008

2008-03-01T12:04:03Z

Al: New page: == How to repair a big bumper scratch == Someone very kindly reversed into my car while trying to park, rather than leaving a note they just did a runner leaving me with a £3-400 repair ...

2008-03-01T11:28:31Z

New page: == How to repair a big bumper scratch == Someone very kindly reversed into my car while trying to park, rather than leaving a note they just did a runner leaving me with a £3-400 repair ...

New page

== How to repair a big bumper scratch ==

Someone very kindly reversed into my car while trying to park, rather than leaving a note they just did a runner leaving me with a £3-400 repair to get the bumper off, resprayed and put back on.

I figured I have nothing to lose by having a go at fixing it myself before I have to pay out anyway, and so this is what I did.

I don't have any fancy rotary sanders or professional spray gear, so I did the best I could with what was available, and it turns out it's perfectly possible to do a reasonable job even if

* you've not done this before
* you don't have pro kit

Obviously it's not going to be as good as a professional job that you'd get if you paid the £400, but it is very rewarding and without close inspection the paint job isn't noticeable.

[[Image:damage.jpg|thumbnail|Thanks a lot !]]

=== Materials ===

Get yourself over to http://www.paints4u.com and order up the following:

* adhesion promoter aerosol
* primer aerosol suitable for priming bumpers
* custom colour aerosol (they'll match on Lotus paint codes)
* lacquer aerosol
* plasticote gun grip attachment for aerosols - this makes a huge difference !
* bumper filler
* a bunch of wet & dry paper at different grades (150 up to 2000)
* some rubbing compound
* automotive grade masking tape
* tub of warm water with washing up liquid and a rag
* tack rag
* degreaser

=== Prep ===

It's all about the prep work, doesn't matter how good you are with the final coat of paint, if the prep work isn't done right, it's not going to look good.

==== Cut out the paint ====

As you can see from the original picture, the damaged area was pretty large with cracked and delaminated paint extending for 30-40cm, to remove all of this paint I took a scalpel and cut around the damaged area, then picked off the chunks of paint.

Do this until you're sure you've removed sufficient paint such that what was left is still securely bonded to the bumper itself.

==== Sanding part 1 ====

Next up, tape around the area you're going to be working on, and get to work sanding down to get a smooth edge on the paint edges.
Since I didn't have any fancy rotary kit this was done by hand. I used 150 grit to do the heavy work.

You should end up with a surface that's smooth to run your finger over, no hard edges where the old paint stops.

Once you're happy that you've sanded enough (see Prep above), wash the area down with the soapy rag - you want to remove all the sanding dust/wax/polish/dead flies/grease/whatever from the area, once it's dried off, go over the area with the degreaser.

[[Image:sanding1.jpg|thumbnail|Sanding down the paint]]

==== Filling ====

Once the area is dry from the washing you just did, mix up some of the bumper filler and apply it to the area you've just sanded down.
Ideally you want to build it back up so that the line of the bumper is slightly proud of how it was originally

I didn't quite put enough filled in one or two places, it's quite difficult to see what the surface contour looks like when it's all matte white, I learnt afterwards that you can spray a very light (one quick pass) coating of a contrasting colour to help with this.

[Image:filler.jpg|thumbnail|Fill in the area to be painted]]

==== Sanding part 2 ====

Once the filler is properly dry, you need to sand it down. What you end up with here is going to be the contour of your finished bumper, so make sure that you're happy with it - you want to get rid of any bumps or edges, and end up with a smooth transition from the original paint to the filler and back again.

wash down with the soapy water again.

==== How to use a spray can ====

* Shake the thing for at least as long as it says on the tin - really - if it says shake for 10 mins, then get a clock, note the time, start shaking and don't stop until the clock says 10mins has passed, not until you think "it's probably been 10mins by now", or until your arm is tired, or until you get bored.
* Use a plastikote spray handle, they clip on to the top of the can and provide you with a handle with a trigger to use - this makes it much easier to move the can in a consistent fashion.
* when you're finished with the can, clean the nozzle by inverting the can and spraying until the paint stops coming out.

===== How to paint from a can=====
* Get a large square of cardboard, and cut a circle out from the middle (about 30cm should be fine).
** You're going to hold this between the can and the car to catch the splatters which happen when you start and stop spraying:
** if you are spraying left-to-right, then you'd start spraying onto the carboard to the left of the hole
** In one smooth motion:
*** move the can to the right so that you're spraying through the hole now onto the target area
*** move the cardboard mask and car to the right in unison, keep spraying through the hold onto the target area
*** once you're at the end of your run stop moving the cardboard, but continue moving the can to the right so that you end up spraying onto the cardboard to the right of the hole
*** stop spraying

Practice a few times using the method above, it takes a bit of getting used to but doing it this way will catch all of the splatters and lumps that occur when you start and stop spraying from a can.

When spraying, '''many light coats are better than 1 heavy coat !''':
Put a light coat down, and wait for it to flash dry before putting the next coat down.

==== Priming 1 ====

Once the area is fully dry, run over it quickly with a tack rag to remove any bits of dust that might have settled on your newly primed work.

If you're happy that it's clean as a whistle, put down a coat or two of the adhesion promotor.

One that's dry, put down 3 or 4 coats of primer and leave to dry.

[[Image:primer.jpg|thumbnail|Apply 3-4 coats of primer]]

You may want to do a test on whether a dark or light primer results in better colour match with your paint - I sprayed over some black and white glossy paper for this.

[[Image:colourmatch.jpg|thumbnail|Test the colour match on dark and light glossy paper]]

==== Sanding 3 ====

wet sand the primer down using 400 grit until you have a smooth finish

Clean the area with the soapy rag.

==== Priming 2 ====

Once the area is fully dry, put down a couple more coats of primer.

==== Sanding 4 ====

wet sand the primer down again using 800 grit, until you have a very smooth finish.

Clean the area with the soapy rag

==== Painting 1 ====

[[:Category:HowTo]]
[[:Category:Incomplete]]

@@ Line 180: / Line 180: @@
 Once you've left it to dry properly, you might want to t-cut in the areas where you're blending the new paint with the old paintwork, then give you car a good deep polish, and cover with a high quality wax, buff up and admire your handiwork !
-[[:Category:HowTo]]
+[[Category:HowTo]]
-[[:Category:Incomplete]]
+[[Category:Incomplete]]

@@ Line 67: / Line 67: @@
 wash down with the soapy water again.
 ==== How to use a spray can ====
@@ Line 160: / Line 162: @@
 Clean up the area with a damp rag.
 ==== Rubbing ====

@@ Line 164: / Line 164: @@
 Get a clean rag and use the rubbing compound to finish off the lacquer, take your time and get it right.
-[[Image:rubbed.jpg|thumbail|After the rubbing compound]]
+[[Image:rubbed.jpg|thumbnail|After the rubbing compound]]
 ==== Finish up ====

@@ Line 22: / Line 22: @@
 * custom colour aerosol (they'll match on Lotus paint codes)
 * lacquer aerosol
-* plasticote gun grip attachment for aerosols - this makes a huge difference !
+* plastikote gun grip attachment for aerosols - this makes a huge difference !
 * bumper filler
 * a bunch of wet & dry paper at different grades (150 up to 2000)
@@ Line 33: / Line 33: @@
 === Prep ===
-It's all about the prep work, doesn't matter how good you are with the final coat of paint, if the prep work isn't done right, it's not going to look good.
+'''It's all about the prep work !'''
 ==== Cut out the paint ====

@@ Line 88: / Line 88: @@
 Practice a few times using the method above, it takes a bit of getting used to but doing it this way will catch all of the splatters and lumps that occur when you start and stop spraying from a can.
-When spraying, '''many light coats are better than 1 heavy coat !''':
+When spraying, '''many light coats are better than one heavy coat !''':
 Put a light coat down, and wait for it to flash dry before putting the next coat down.

@@ Line 60: / Line 60: @@
 I didn't quite put enough filled in one or two places, it's quite difficult to see what the surface contour looks like when it's all matte white, I learnt afterwards that you can spray a very light (one quick pass) coating of a contrasting colour to help with this.
-[Image:filler.jpg|thumbnail|Fill in the area to be painted]]
+[[Image:filler.jpg|thumbnail|Fill in the area to be painted]]
 ==== Sanding part 2 ====

@@ Line 1: / Line 1: @@
 == How to repair a big bumper scratch ==
-Someone very kindly reversed into my car while trying to park, rather than leaving a note they just did a runner leaving me with a £3-400 repair to get the bumper off, resprayed and put back on.
+Someone very kindly reversed into my car while trying to park, rather than leaving a note they just did a runner leaving me with a £3-400 repair to get the bumper off, re-sprayed and put back on.
-I figured I have nothing to lose by having a go at fixing it myself before I have to pay out anyway, and so this is what I did.
+I figured I had nothing to lose by having a go at fixing it myself before I'd have to pay out anyway, and so this is what I did.
 I don't have any fancy rotary sanders or professional spray gear, so I did the best I could with what was available, and it turns out it's perfectly possible to do a reasonable job even if

@@ Line 117: / Line 117: @@
 wet sand the primer down again using 800 grit, until you have a very smooth finish.
-Clean the area with the soapy rag
+Clean the area with the soapy rag, and once it's dry go over it again with the tack rag.
-==== Painting 1 ====
+==== Painting ====
 [[:Category:HowTo]]
 [[:Category:Incomplete]]