Can you really burn car paint with a Dewalt 849 Polisher ?

F

frankosmusica

New member
I have a Dewalt 849 polisher I want to polish my own car, So I went and bought polishing compound medium scratch one and the three buffing pads. The cutting,poolishing, and finishing. Can paint really be burnt ? Ive heard many opinions many say if you stay on the same spot for a long time, some say not really if you have it in low RPM anywhere from 1000 to 1800. How good is a Porter Cable 7424 compared to the Dewalt 849 ? I heard the Porter Cable 7424 polisher is so safe that you can never burn paint with that one because of the way it spins ? This is what the guys from an auto detailing store told me how true is this ?
 
Strike-through and Paint burn have a very similar cause and affect



Speed, kinetic energy (friction), applied pressure, foam pad actual surface contact area, pad and polish / compound abrasive ability, amount of surface lubrication available, area being polished, and material (paint, especially paint edges, plastic, metal, etc) heat conductivity



The above factors using a slow to stationary linier motion will produce excessive ‘friction heat ‘on a paint surface wither it be a rotary or an orbital polisher; the operative word here is excess friction. Basically strikethrough is caused when kinetic energy (friction heat) has compromised the clear coat and exposed the base coat. Paint often looks a slightly lighter colour; it’s usually concentrated on a small area or ‘spot ‘



You will also be able to see a non-glossy patch (base coat) where the clear has been removed with the edges of the remaining clear coat being visible. Since the clear coat contains the UV inhibitors, the colour coat is now exposed and will be subjected to photo degradation (fading)









FWIW- posting the same question in different sections probably won't give you better answers
 
from my experience, there are two types of paint burning



A: PAD BURN: pad scours the paint like you are using an angle grinder or wire brush at high speed.

B: DELAMINATION: Too much speed, pressure,friction, heat from rotary buffing that the paint gets too hot and the clear delaminates and bubbles up in certain spots.



I have done both - the second one done deliberately to see how far I can push it with a rotary.



Its surprising that often it is the orange CCS pads, megs burgundy pads and black finishing pads that cause pad burn the most. especially black pads that are extremely smooth/soft
 
Short answer- yes you can burn paint with the rotary @ that rpm AND with the PC if you try. Feel the paint as you're polishing, you'll see how hot it gets.
 
You can burn the paint with anything that contacts the paint if it is spinning fast enough and has enough pressure, these factors happen quicker with a rotary than a DA usually. A lot depends on the pad size and speed in this situation.
 
What you need to do is go out and get your hands on a scrap panel, and start buffing. I'd suggest that you actually TRY to burn the paint. Once you've learned how to do that, file it under "how NOT to buff" and start working on proper technique to avoid causing damage.
 
Definitely can. Just keep it moving along and you'll be fine. Touch the paint after doing a section - it will surprise you how hot it can get.
 
SVR said:
Its surprising that often it is the orange CCS pads, megs burgundy pads and black finishing pads that cause pad burn the most. especially black pads that are extremely smooth/soft
Click to expand...



A finer pad should have more surface area, and thus be able to build up heat faster.
 
Short answer- yes you can burn paint with the rotary @ that rpm AND with the PC if you try.

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