PS ONLY FOLLOW THIS IF YOU WISH TO DESTROY YOUR PAINT!!!
The aim of today was to practice rotary use to destruction on a panel to see how much paint is removed by different processes.
First up we had a badly oxidised ford red bonnet that I picked up from the local scrappy. We taped off the areas to work on. You can just notice some trees trying to break through the dull shine of the red .
The paint thickness was measured in the small area taped off. We used a Landtek paint thickness guage that measures in microns or 1000ths of an millimeter. We took 7 readings across this area, the average across this area was 89 microns the paint was thicker to the left 104 and thinner at the right around 80.
We then started with meguiars #80 on the cyclo, the panel was now a nice deeper red and the white pads were stained red!! However the paint reading only dropped to an average of 86.9 microns. This demonstrates minimal - safe paint removal to achieve the desired shine.
But thats not what this test was exclusivly about:devil:
I think its fair to say we were itching to crack open the big guns so we jumped straight to meguiars #84 (rated 9/10 on the abrasive scale :doublesho ) using the makita rotary we started on speed 1, then 3 and finally 6 really giving it some welly:driver:
I took the first shift and after using the big boys we then measured the paint again and found an average thickness of 81.8 microns.
So thats 5 microns lost using almost the heaviest gun.
I said almost
Ben brought his diamond cut meguiars #85 (rated 10/10 on the abrasive scale :doublesho :doublesho )
Here Ben gives it a good compounding
What surprised us the most was how nicely these heavyweights broke down to a pretty good swirl free (but not hologram free) finish.
Next up we re measured the paint and found an average of 75 microns, so another 6 had fallen by the wayside.
Plenty left to play with?
Not so it would seem a black area that appeared underneath the red had formed. When measured this was 48.4 microns. A thin spot in the paint had been revealed and the black primer was faintly visible. :buffer:
Next up AlexL chose a megiars burgundy cutting pad and some #84 to try and concentrate some heat into the thin spot.
After a what can only be described as a seriously heavy and prolonged compounding the thin spot had dropped to 38.9 microns. After each pass we spryaed the panel wth QD to create some steam!
So it was left to me to kill the panel:devil:
I stuck with the 'spot' megs cutting pad and the #84 and more pressure than was really needed and 3000 rpm and I was 'smoking'
AFter hanging on for dear life for waht seemed an age the pad started to break up, smoke was coming from the panel and finally we had burnt through!!
And the afters?
The circled area is bare metal lol
The debris from the dead megs cutting pad
Conclusion - usual disclaimers apply!
It takes a fair amount of effort to burn the paint and even go through the paint, we had so many warning signs, heat, steam, smoke, exploding pads and yet we ignored them all
A reasonably comptetent person could pick up a rotary and at worst instill swirls and holograms wihout totally fubarring the paint. However the above readings are total film build and do not separate out between the primer and colour coat or in the event of clearcoated paint the clearcoat itself. It has told us that to compound safely a paint thickness meter is essential to test how much is being removed. The danger of a thin spot is always there as we found today
The end readings were 5.5 microns on what appeared to be bare metal (obviously had some paint on) and 28 microns on the surounding primer.
Next up we tested a clearcoated panel with swirls
BenP used the wool pad and #85 to clear them, to a pretty good finish on its own:thumb:
^^Left side polished, right side not
^^Before
^^after
The aim of today was to practice rotary use to destruction on a panel to see how much paint is removed by different processes.
First up we had a badly oxidised ford red bonnet that I picked up from the local scrappy. We taped off the areas to work on. You can just notice some trees trying to break through the dull shine of the red .
The paint thickness was measured in the small area taped off. We used a Landtek paint thickness guage that measures in microns or 1000ths of an millimeter. We took 7 readings across this area, the average across this area was 89 microns the paint was thicker to the left 104 and thinner at the right around 80.
We then started with meguiars #80 on the cyclo, the panel was now a nice deeper red and the white pads were stained red!! However the paint reading only dropped to an average of 86.9 microns. This demonstrates minimal - safe paint removal to achieve the desired shine.
But thats not what this test was exclusivly about:devil:
I think its fair to say we were itching to crack open the big guns so we jumped straight to meguiars #84 (rated 9/10 on the abrasive scale :doublesho ) using the makita rotary we started on speed 1, then 3 and finally 6 really giving it some welly:driver:
I took the first shift and after using the big boys we then measured the paint again and found an average thickness of 81.8 microns.
So thats 5 microns lost using almost the heaviest gun.
I said almost
Ben brought his diamond cut meguiars #85 (rated 10/10 on the abrasive scale :doublesho :doublesho )
Here Ben gives it a good compounding
What surprised us the most was how nicely these heavyweights broke down to a pretty good swirl free (but not hologram free) finish.
Next up we re measured the paint and found an average of 75 microns, so another 6 had fallen by the wayside.
Plenty left to play with?
Not so it would seem a black area that appeared underneath the red had formed. When measured this was 48.4 microns. A thin spot in the paint had been revealed and the black primer was faintly visible. :buffer:
Next up AlexL chose a megiars burgundy cutting pad and some #84 to try and concentrate some heat into the thin spot.
After a what can only be described as a seriously heavy and prolonged compounding the thin spot had dropped to 38.9 microns. After each pass we spryaed the panel wth QD to create some steam!
So it was left to me to kill the panel:devil:
I stuck with the 'spot' megs cutting pad and the #84 and more pressure than was really needed and 3000 rpm and I was 'smoking'
AFter hanging on for dear life for waht seemed an age the pad started to break up, smoke was coming from the panel and finally we had burnt through!!
And the afters?
The circled area is bare metal lol
The debris from the dead megs cutting pad
Conclusion - usual disclaimers apply!
It takes a fair amount of effort to burn the paint and even go through the paint, we had so many warning signs, heat, steam, smoke, exploding pads and yet we ignored them all
A reasonably comptetent person could pick up a rotary and at worst instill swirls and holograms wihout totally fubarring the paint. However the above readings are total film build and do not separate out between the primer and colour coat or in the event of clearcoated paint the clearcoat itself. It has told us that to compound safely a paint thickness meter is essential to test how much is being removed. The danger of a thin spot is always there as we found today
The end readings were 5.5 microns on what appeared to be bare metal (obviously had some paint on) and 28 microns on the surounding primer.
Next up we tested a clearcoated panel with swirls
BenP used the wool pad and #85 to clear them, to a pretty good finish on its own:thumb:
^^Left side polished, right side not
^^Before
^^after