Pilot Pete wrote: ↑Tue Oct 11, 2022 9:16 pm Phil, the DA is actually very easy - like you I spent years doing cars by hand and you are right it’s bloomin’ hard work!
The key is getting a half decent DA, a range of pads, a couple of polishes with cut and less cut/ more polish and do a bit of research regarding how hard the paint is on your car.
Start with the ‘weakest’ or ‘least cut’ combination of pad/ polish and do a test panel - if it cuts and polishes enough then go with that combo. If it doesn’t increase the cut by one level (heavier cut pad or heavier cut polish) until you get the right combo.
Actually using the DA is simplicity itself - you smear your clean pad with a load of polish and rub it in. That primes the pad. Then pick an area about 2’ square. Put three pea sized blobs of polish on the pad equally spaced. DAB the pad around on the panel area to ‘blob’ the polish across the area to be polished. Put the DA on a low speed setting, hold against the panel and switch it on. Now simply move the pad across the surface to spread the polish evenly around the chosen area.
Now switch the speed up and with the pad in contact with the panel switch on the DA. Start in one corner, gently push the pad into the panel and move the pad across the surface fairly slowly from side to side, like ploughing a field, but overlap each pass by half the width of the pad. Once you have done the horizontal ‘stripes’, now do a set of vertical passes across the same area using a similar technique. Stop the DA with the pad still in contact with the panel.
You will notice after you start your passes the polish turns clear and this is it breaking down and starting to do its thing. Don’t pass too fast, give the pad time to do it’s work. Don’t go too slow either, you will simply ‘get’ what feels right.
Wipe the remaining polish off with a microfibre towel and then inspect the area. Has it removed the defects? Has it polished to a shine? Does it need more correction or is the result to your standards? Can you actually do more correction? If a defect is too deep you can’t just keep polishing or you will strike through the clear coat and need a respray! However, a DA is very forgiving, which makes it most suitable for beginners and amateurs alike. I, like you, was concerned before I did my first car but really needn’t have worried. The results were spectacular compared to hand polishing, in a fraction of the time.
The ideal solution is to get a mate who has a DA show you how to use it and do one panel on your car for you, letting you do part of it too. It’s really not that difficult, honest!
Great write up, and there's a shed load of videos online that provide tutorials.
You touched on paint hardness - From experience, JLR paint and clear coat is soft compared to most other manufacturers standards.
What I think needs to be taken into consideration is paint thickness.
We've taken paint depth measurements way back in 2014/15, they are in the Forum archives somewhere!
The depths vary wildly form panel to panel. That said, it may have improved over the years?
Personally - I wouldn't be going near a car without first knowing the paint thickness, then could gauge just how much or how little I could machine polish.
