Machine and plastic parts???

[Civicman86]

I was reading Mikes`s "book" on detailing. In it he says not to use a machine on plastic parts like the bumpers as it "smears" the finish (this because of the flex agent added to the paint).



Does anyone else have experience with this??





Also how does one remove scratches from parts like door handles? And the area under the door handles? Obviously a machine pad is not going to fit. Should I get a certain polish that can be broken down by hand to do these parts?

[Accumulator]

I was reading Mikes`s "book" on detailing. In it he says not to use a machine on plastic parts like the bumpers as it "smears" the finish (this because of the flex agent added to the paint).



Does anyone else have experience with this??



Not me. I use machines (rotaries/Cyclos/PCs) on painted bumper covers with no problems at all. You *do* need to remember that plastic behaves different from metal though, so turn down the speed and don`t get too aggressive when working with the rotary.






Also how does one remove scratches from parts like door handles? And the area under the door handles? Obviously a machine pad is not going to fit. Should I get a certain polish that can be broken down by hand to do these parts?



Yeah, where a machine won`t fit you need to work by hand. I generally start with 1z Ultra/Extra on cotton, from there I go to (the discontinued) 3M PI-III RC 05933 first with cotton terry then with MF or foam, then (the also discontinued) 3M PI-III MG 05937 with MF or foam, and finally a finishing polish if it`s one of the good vehicles.



I`ve been able to remove fingernail scratches from behind the door handles of our Audis...but it sure did take a lot of time and effort.



With the 3M PI-III stuff getting hard to find, you might try substituting H-T Heavy Cut for the 05933 and 1z Paint Polish for the 05937. People who like Meg`s stuff could try #2 (new version) or #83 followed by #80. I bet there are even better choices from Menzerna and others, but I`ve yet to try them.

[SVR]

Machine polishing bumpers and door trim materials is fine

You just have to use the stop and go method with bumpers, probably limit the polish used to a 1200 grit with a white or orange pad and keep the rpm`s down



Or use non abrasive products like glare, permagard, poorboys

[imported_Totoland Mach]

I was reading Mikes`s "book" on detailing. In it he says not to use a machine on plastic parts like the bumpers as it "smears" the finish (this because of the flex agent added to the paint).



Does anyone else have experience with this??





Also how does one remove scratches from parts like door handles? And the area under the door handles? Obviously a machine pad is not going to fit. Should I get a certain polish that can be broken down by hand to do these parts?



I use a machine on plastic body panels almost daily. The key is preventing too much heat from the machine (specifically a rotary) from burning the plastic. Since I`ve switched to wool pads for most correction (which doesn`t generate heat as quickly as foam), my burns have dropped to zero. Also, when correcting a scratch on plastic, you can check the temp of the area with the back of your hand. If it`s getting too warm, move on to another area and return when it cools down a little.



Door handles: For handle recess, I use Optimum or 3M compound on a terry towel and rub vigorously at right angles to the scratches (typically fingernail type). Then follow that with any decent polish (Meg`s 83, etc) and a microfiber to quickly finish it off. I can typically do 4 door handles in just a few minutes. For the handle itself, I wet sand lightly because this part is usually pot metal and can burn easily, the use the rotary lightly.



Here`s a couple of shots of that process:



Before



http://i121.photobucket.com/albums/o212/Totoland/July07_BMWs/740i_Black_DoorHandleBefore.jpg



Sanded handle



http://i121.photobucket.com/albums/o212/Totoland/July07_BMWs/740i_Black_DoorHandleWetSanded.jpg



Done



http://i121.photobucket.com/albums/o212/Totoland/July07_BMWs/740i_Black_DoorHandleAfter.jpg



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