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MirrorFinish
03-14-2012, 04:13 PM
Hi.
I do a fair amount of orange peel removal here in the UK by wet sanding.

My question is how do I check for the flatness in the panel without having to keep polishing back to panel first; I am sure there is a logical answer???

Thanks guys
Steve

Setec Astronomy
03-14-2012, 04:27 PM
I've never sanded specifically to remove orange peel, but you ARE using a block correct? You will hit the high spots first which will go dull, and then you will see the low spots remaining...when there are no low spots, you are flat. Or are you talking about you can't tell when you've removed the sand scratches when you change grit? A tip is to sand in straight lines and change direction when you change grit--up-down, then left-right.

MirrorFinish
03-14-2012, 05:06 PM
I've never sanded specifically to remove orange peel, but you ARE using a block correct? You will hit the high spots first which will go dull, and then you will see the low spots remaining...when there are no low spots, you are flat. Or are you talking about you can't tell when you've removed the sand scratches when you change grit? A tip is to sand in straight lines and change direction when you change grit--up-down, then left-right.

Hi
The peel in European cars is really bad and can take 2-3 hits to remove. I block the car with 2000, 2500, 3000 and 4000 grit and get it flat. The problem is orange peel is still there.

So could this peel be in the base layer or am I not getting the clear totally flat??

I don't have any sanding marks as I would rather 2000 gtit it twice than use 1500 grit and I finish off with 4000 grit Mirka pads on a DA. I sand in alternate directions as well as diagionally.

it is just the polishin out bit to kepe checking that is really adding time to the jobs.

Setec Astronomy
03-14-2012, 05:23 PM
Oops, I didn't realize this was in Mike's forum. I'm sure part of his answer will be to link to these articles of his:

EDIT: Well that didn't work--go to this page and scroll down to the sanding articles: http://www.autogeekonline.net/forum/ask-expert-featuring-mike-phillips/23722-articles-mike-phillips.html

Rsurfer
03-14-2012, 07:53 PM
Are you not the same Mirror Finish (Steve) on DW that is charging for a wet sanding class?
Hi.
I do a fair amount of orange peel removal here in the UK by wet sanding.

My question is how do I check for the flatness in the panel without having to keep polishing back to panel first; I am sure there is a logical answer???

Thanks guys
Steve

Dadillac
03-14-2012, 08:26 PM
When I wet sand I can always tell where I haven't hit. As stated before when you are sanding wipe away the residue (use IPA on a rag). If the area has any shiny spots then those are the low spots that still remain. If the area is completely dull then you are ready to polish it up

Don

andyo
03-14-2012, 08:56 PM
a old trick is to use 2 wooden paint sticks one on top of another and wrap them with 2000 grit and sand til the shiny spots are almost done then use 2500 til shiny spots are gone then compound. the paint sticks are harder than sanding blocks and wont gauge the paint. cut the paint sticks to a manageable length.

MirrorFinish
03-15-2012, 10:42 AM
I'll have to stick with the tape method and multiple readings. Just thought there may be some scope or machine in the US to speed this up.

Mike Phillips
03-15-2012, 12:20 PM
Hi.
I do a fair amount of orange peel removal here in the UK by wet sanding.

My question is how do I check for the flatness in the panel without having to keep polishing back to panel first; I am sure there is a logical answer???

Thanks guys
Steve

Hi Steve,

Normally what I do is have a few extra flat, foam rubber sandpaper backing pads in my bucket of sandpaper and water and use one like a squeegee to remove the water slurry off the panel and then inspect the surface.


Here's a few pictures of the above from one of my advancec classes on wetsanding,



Pictures & Comments from September 19th Detailing 102 Class (http://pictures%20&%20comments%20from%20september%2019th%20detailing% 20102%20class/)

Demonstrating correct hand-sanding techniques starting with Meguiar's Nikken #1500 Unigrit Finishing Papers
http://www.autogeekonline.net/gallery/data/936/Sept19ADVClass005.jpg


After sanding you can often times use a clean sanding backing pad to squeegee off the water slurry to then inspect your progress...
http://www.autogeekonline.net/gallery/data/936/Sept19ADVClass006.jpg

http://www.autogeekonline.net/gallery/data/936/Sept19ADVClass006c.jpg




Like Don aka Dadillac posted,





If the area has any shiny spots then those are the low spots that still remain. If the area is completely dull then you are ready to polish it up

Don


As you're sanding the tops off the orange peel the low points will remain shiny, when you squeegee off the water slurry if the paint is not flat yet you'll see shiny divots or spots on the surface. You want to sand till the surface is flat and no high/low points remain.


I have a 1940 Ford Truck coming up for a wetsand, cut and buff with quite a bit of orange peel, I'll try to capture some picture but it won't be till after Detail Fest.



Basic Hand Sanding Techniques (http://www.autogeekonline.net/forum/wet-sanding-cutting-buffing/21974-basic-hand-sanding-techniques.html)

The Rule of Thumb (http://www.autogeekonline.net/forum/wet-sanding-cutting-buffing/25042-rule-thumb.html)

Wet-sanding - Fresh Paint vs Factory Paint (http://www.autogeekonline.net/forum/wet-sanding-cutting-buffing/21471-wet-sanding-fresh-paint-vs-factory-paint.html)

Removing Orange Peel & Sanding Marks with the Griot's ROP and the Wolfgang Twins (http://www.autogeekonline.net/forum/wet-sanding-cutting-buffing/21463-removing-sanding-marks-griot-s-rop-wolfgang-twins.html)



:xyxthumbs:








Basic Hand Sanding Techniques (http://www.autogeekonline.net/forum/wet-sanding-cutting-buffing/21974-basic-hand-sanding-techniques.html)

MirrorFinish
03-15-2012, 12:45 PM
Cheers Mike

I think the peel in european cars must be pretty bad compared to US cars. It is taking a week to flat them properly and a lot of tape to keep checking.

Wish there was some super paint depth guage that would fire at the car and do the readings automitaclly.

Steve

RaskyR1
03-15-2012, 01:20 PM
Cheers Mike

I think the peel in european cars must be pretty bad compared to US cars. It is taking a week to flat them properly and a lot of tape to keep checking.

Wish there was some super paint depth gauge that would fire at the car and do the readings automatically.

Steve

I doubt the peel is any worse than some of the cars we have around here...some are pretty ridiculous. :(

If the peel is that bad you'd be better of starting with a more aggressive paper (1000-1500) and just knocking down the majority of the high points first before going with the 2000. You could probably skip the 4000 grit step too as the amount of time saved polishing is minimal compared to 3000 grit, at least IME.

If this is on OEM paint I'm not sure I'd try and get the paint fully level anyway.





Rasky

MirrorFinish
03-15-2012, 07:24 PM
I doubt the peel is any worse than some of the cars we have around here...some are pretty ridiculous. :(

If the peel is that bad you'd be better of starting with a more aggressive paper (1000-1500) and just knocking down the majority of the high points first before going with the 2000. You could probably skip the 4000 grit step too as the amount of time saved polishing is minimal compared to 3000 grit, at least IME.

If this is on OEM paint I'm not sure I'd try and get the paint fully level anyway.





Rasky
Thanks
That is the problem, customers want the paint fully flat with no peel at all.

It is slightly different here as a lot of cars are either company cars or leased, so the first owner wants perfection and as we only tend to keep cars for two to three years the removal of the paint is not an issue. I have been forced to take 1.5 to 2 mil off a brand new Range Rover before.

My wife gets a new company car every two years and free company fuel; apart from a tax adjustment, you can see how we are pressured to get the clear totally flat even if it takes off too much clear as the car is sold at auction.

Mike Phillips
03-16-2012, 06:50 AM
Cheers Mike

I think the peel in european cars must be pretty bad compared to US cars. It is taking a week to flat them properly and a lot of tape to keep checking.

Wish there was some super paint depth guage that would fire at the car and do the readings automatically.

Steve


Orange Peel can be flattened very quickly simply by dropping down to very aggressive sandpaper, for example #800 Grit.

Are we talking about cars that have been repainted or factory finishes?

If we're talking about repaints, then hopefully the paint is thick so you have plenty of film-build to work with.

Check out this Advanced Wetsanding Class I taught using a 1971 GTO with EXCESSIVE Orange Peel. I used a team of guys that have never sanded before nor used a rotary buffer to remove sanding marks and we knocked it out to about 95% and I finished the other 5% on my day off...


1971 GTO - Wetsand, Cut and Buff (http://www.autogeekonline.net/forum/show-n-shine/38636-1971-gto-wetsand-cut-buff.html)

Pictures & Comments from July 10th, 2011 Sunday Detailing 102 - Advanced Class (http://www.autogeekonline.net/forum/pictures-sunday-detailing-102-advanced-class/38253-pictures-comments-july-10th-2011-sunday-detailing-102-advanced-class.html)


BEFORE

http://www.autogeekonline.net/gallery/data/1206/1971GTODampSand001.jpg

http://www.autogeekonline.net/gallery/data/1206/1971GTODampSand002.jpg

http://www.autogeekonline.net/gallery/data/1206/1971GTODampSand003.jpg


http://www.autogeekonline.net/gallery/data/1206/1971GTODampSand004.jpg







AFTER


http://www.autogeekonline.net/gallery/data/1206/GTOPearl01.jpg


http://www.autogeekonline.net/gallery/data/1206/GTOPearl02.jpg


http://www.autogeekonline.net/gallery/data/1206/GTOPearl03.jpg


http://www.autogeekonline.net/gallery/data/1206/GTOPearl04.jpg


http://www.autogeekonline.net/gallery/data/1206/GTOPearl05.jpg



http://www.autogeekonline.net/gallery/data/1206/GTOPearl07.jpg

http://www.autogeekonline.net/gallery/data/1206/GTOPearl06.jpg

http://www.autogeekonline.net/gallery/data/1206/GTOPearl18.jpg

http://www.autogeekonline.net/gallery/data/1206/GTOPearl19.jpg



:props:

RaskyR1
03-16-2012, 08:57 AM
Thanks
That is the problem, customers want the paint fully flat with no peel at all.

It is slightly different here as a lot of cars are either company cars or leased, so the first owner wants perfection and as we only tend to keep cars for two to three years the removal of the paint is not an issue. I have been forced to take 1.5 to 2 mil off a brand new Range Rover before.

My wife gets a new company car every two years and free company fuel; apart from a tax adjustment, you can see how we are pressured to get the clear totally flat even if it takes off too much clear as the car is sold at auction.

That's removing a LOT of paint, actually that's almost all of the clear on most factory cars, at least those in the US. I've seen several brand new Infiniti's with low readings in the 2.75 mil range....and that's from the base metal to the top of the clear!

IMO you really need to push back on your clients, inform them that the car manufactures state that removing more than .3-.5 mil from the clear coat can result in inadiquate UV protection and possible clear coat failure. I definitely think you can safely remove some of the orange peel from these cars, but you need to try and stay within the manufactures recommendations. I understand that these owners only keep the cars for a few years and could care less what happens after they turn the car back in, but what about the next owner? IMO following through with their wants of removing excessive clear is really kind of wreck-less for a detailer. What happens when the next detailer has to do minor correction on the car and they rub through using only a mild polish simply because there was little to no clear left? What if that next guy is you?

As detailers we need to educate our clients of these risks and be willing to say NO when the request is simply unreasonable.

Again, paint on your side of the pond may be different then ours here in the US, and I don't want you to think I'm attacking you either. I've followed your work on DW and I know you're more than capable in doing this kind of work. What I wrote above is more for the other peeps that may reading this. ;)


Cheers,
Rasky

Mike Phillips
03-16-2012, 09:08 AM
That's removing a LOT of paint, actually that's almost all of the clear on most factory cars, at least those in the US. I've seen several brand new Infiniti's with low readings in the 2.75 mil range....and that's from the base metal to the top of the clear!

IMO you really need to push back on your clients, inform them that the car manufactures state that removing more than .3-.5 mil from the clear coat can result in inadiquate UV protection and possible clear coat failure.


As detailers we need to educate our clients of these risks and be willing to say NO when the request is simply unreasonable.





Awesome advice Chad...


:dblthumb2: