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Our last Advanced Class of the year and the students showed excellent results all around. More important though, they showed that they were thinking about what they were doing and assessing their work as they went. Great stuff!!!
As per usual, following the classroom portion of the day we stepped outside for the hands on portion. We start with demos of hand sanding, DA sanding and rotary compounding/polishing.
As the sanding marks are refined, we actually start to pick up some gloss and reflections. On the right side is 1500 grit DA sanding marks, on the left side is after refining with 3000 grit.
Time to pull out those sanding marks!
A wool pad can make attacking tight contours a snap.
After a quick lunch, it's time to cut loose and let the students get acquainted with these processes.
Watch those edges! This is a close up of a panel edge and it tells a very important story. The person sanding on this panel was NOT working on the area you see here, but rather the area just outside this image to the top and slightly left. It was on the backstroke of his hand sanding that he was hitting the edge of the panel and removing a lot of material. The seemingly random straight line scratches are the edge of his work area, and that's fine. But that totally dull line along the edge is an indicator that he was taking a lot of material off very close to the edge.... and he had no idea he was doing this. Wet sanding has the potential to remove a lot of paint, so you need to hyper vigilant about your work area and the surrounding areas.
How do you like this paint texture? Pretty horrible, right?
After some initial sanding you can see that only the high spots of the texture have been touched with the abrasive here. The shiny areas are the low spots of the texture that have not been touched. Yet.
This is pretty good hand sanding technique - you can see very tight overlaps and short strokes. Honestly, the overlap could maybe be a bit tighter, but at least these are very evenly spaced, which helps create very uniform sanding marks, and that is what we're after.
After 3000 grit DA sanding we start to really bring back the gloss. But you can also see that we're bringing clarity to the surface as the reflections of the overhead lights are nice and crisp.
A nice 50/50 shot - on the left is untouched, heavily textured paint. The reflection is a blurry, fuzzy mess. On the right side you see the result of proper sanding and compounding/polishing to restore gloss and clarity to the paint. Not too shabby for someone who had never wet sanded or rotary buffed before!
Residual sanding marks in two directions. That means you're looking at the remnants of two different grits of sandpaper, and that means the operator probably needed to refine his sanding marks a bit further before moving to the rotary. Either that or he's got a LOT more buffing to do to remove these marks. So there are two options here: 1) wet sand with a finer grit media to refine the sanding marks and then quickly rotary compound to remove those marks, or 2) just grind away with a rotary, an aggressive pad and a strong compound until you've beaten those marks into submission. Option 1) introduces no heat to the paint and is actually very non invasive. Option 2) can generate a lot of heat, which modern paint just doesn't like, and is less controlled than Option 1). Which would you choose?
And to finish off, a couple of self portraits in paint. Yes, these are reflections of students who created this level of gloss and clarity in the paint with their new found sanding and rotary skills.
As per usual, following the classroom portion of the day we stepped outside for the hands on portion. We start with demos of hand sanding, DA sanding and rotary compounding/polishing.
As the sanding marks are refined, we actually start to pick up some gloss and reflections. On the right side is 1500 grit DA sanding marks, on the left side is after refining with 3000 grit.
Time to pull out those sanding marks!
A wool pad can make attacking tight contours a snap.
After a quick lunch, it's time to cut loose and let the students get acquainted with these processes.
Watch those edges! This is a close up of a panel edge and it tells a very important story. The person sanding on this panel was NOT working on the area you see here, but rather the area just outside this image to the top and slightly left. It was on the backstroke of his hand sanding that he was hitting the edge of the panel and removing a lot of material. The seemingly random straight line scratches are the edge of his work area, and that's fine. But that totally dull line along the edge is an indicator that he was taking a lot of material off very close to the edge.... and he had no idea he was doing this. Wet sanding has the potential to remove a lot of paint, so you need to hyper vigilant about your work area and the surrounding areas.
How do you like this paint texture? Pretty horrible, right?
After some initial sanding you can see that only the high spots of the texture have been touched with the abrasive here. The shiny areas are the low spots of the texture that have not been touched. Yet.
This is pretty good hand sanding technique - you can see very tight overlaps and short strokes. Honestly, the overlap could maybe be a bit tighter, but at least these are very evenly spaced, which helps create very uniform sanding marks, and that is what we're after.
After 3000 grit DA sanding we start to really bring back the gloss. But you can also see that we're bringing clarity to the surface as the reflections of the overhead lights are nice and crisp.
A nice 50/50 shot - on the left is untouched, heavily textured paint. The reflection is a blurry, fuzzy mess. On the right side you see the result of proper sanding and compounding/polishing to restore gloss and clarity to the paint. Not too shabby for someone who had never wet sanded or rotary buffed before!
Residual sanding marks in two directions. That means you're looking at the remnants of two different grits of sandpaper, and that means the operator probably needed to refine his sanding marks a bit further before moving to the rotary. Either that or he's got a LOT more buffing to do to remove these marks. So there are two options here: 1) wet sand with a finer grit media to refine the sanding marks and then quickly rotary compound to remove those marks, or 2) just grind away with a rotary, an aggressive pad and a strong compound until you've beaten those marks into submission. Option 1) introduces no heat to the paint and is actually very non invasive. Option 2) can generate a lot of heat, which modern paint just doesn't like, and is less controlled than Option 1). Which would you choose?
And to finish off, a couple of self portraits in paint. Yes, these are reflections of students who created this level of gloss and clarity in the paint with their new found sanding and rotary skills.
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