The whole idea behind not removing too much clear is very confusing..

[WRAPT C5Z06]

I just watched a YouTube video that basically mentioned, if you do more than polish, you may remove the important top layer of UV protection. With that said, why the need for long throws, rotaries, compounds, etc...Grab yourself a GG 6", polish and finishing pad and you're good to go.

I bought a test hood with OEM Volvo paint. I sanded with 1000 grit several times, sanded with 2000 grit several times, sanded with 3000 grit several times, compounded many times, polished many times and FINALLY went through the clear. Point being, this OEM THIN clear took one hell of a BEATING before it finally went through.

What gives?

Sent from my ONEPLUS A6013 using Autogeekonline mobile app (http://r.tapatalk.com/byo?rid=87407)

[DBAILEY]

I remember the rule of thumb being that the UV protection migrates to the top half of the clear coat when drying. So you should never remove more than half of the clear. That is, if you have the ability to calculate the thickness of just the clear.

A typical heavy compounding may remove 5-10 microns depending on how deep you need to go. Should have more than half of that top 50% left over.

[Dr Oldz]

Without getting too complicated and to give a very basic answer:

After paint cures(more specifically the clear coat) the UVA and UVB inhibitors eventually migrate to the top 30% of the clear coat. That is the part we polish/compound off. This Information comes direct from a local PPG automotive paint rep.

The only product I know that claims to add this protection back to the clear is OCW(with continued use)and I believe that is the main part of the patent for OCW.

[pilotpip]

Why long throws? Efficiency. With more power they can do as much in 3-4 passes as a GG6 or PC can do in 5-6. One pass doesn't sound like much but over an entire car it adds up. An enthusiast doing 3 or 4 cars a year might not see a need for that, but pros certainly do. That time savings could mean the ability to correct 2 or 3 cars a week which adds to their bottom line.

[WRAPT C5Z06]

Why long throws? Efficiency. With more power they can do as much in 3-4 passes as a GG6 or PC can do in 5-6. One pass doesn't sound like much but over an entire car it adds up. An enthusiast doing 3 or 4 cars a year might not see a need for that, but pros certainly do. That time savings could mean the ability to correct 2 or 3 cars a week which adds to their bottom line.You're missing my point. With these aggressive machines, you're most likely removing the most important top part of the clear.

Sent from my ONEPLUS A6013 using Autogeekonline mobile app (http://r.tapatalk.com/byo?rid=87407)

[DBAILEY]

I have a few clients that don't get this. They know that I can remove the swirls that they put in the car, but never seem to care about my warnings that I can't keep doing this and they need to be more gentle with their car.

It kills me to see people constantly polishing their hoods and roof testing coatings and other LSP all the time. Some of you guys are nuts.

[WRAPT C5Z06]

I have a few clients that don't get this. They know that I can remove the swirls that they put in the car, but never seem to care about my warnings that I can't keep doing this and they need to be more gentle with their car.

It kills me to see people constantly polishing their hoods and roof testing coatings and other LSP all the time. Some of you guys are nuts.Do you own a compound? Serious question.

Sent from my ONEPLUS A6013 using Autogeekonline mobile app (http://r.tapatalk.com/byo?rid=87407)

[DBAILEY]

Yes, I have probably 6-8 compounds. FG400 is probably my all around favorite.

[DBAILEY]

If you're at 100 microns total thickness and subscribe to the 25% primer, 25% base color and 50% clear coat then the UV should be in the top 25-30% which would be about 12-15 microns. So there is some room for correction. You're just weakening the clear's ability to block or absorb the UV.

So I guess it's a trade off with obvious limits.

[davidc]

Exactly why I picked up some glaze this time. Gonna try it with 476.

[SWETM]

Swedish quality LOL.

Interesting discussion this. What I have seen is that with a proper sanding you can level less clearcoat than a heavy compounding on the same defects. Was a video from Rupes training center with Jason Rose doing a trunk that was pretty beatened up from swirlomatic car washes I think he said. It was on Obsessed Garage when Matt where at the Rupes in Colorado. The readings after each step with a paint thickness gauge was mind boggleing for me. It was very little clearcoat they took off to get it defect free. And it seemed to be more control over it than heavy cutting compounding it. Then your results is also interesting that it an oem paint can handle a lot of sanding. And it sure is not to be diving in head first when doing sanding. But as you do test it out on a test panel.

[Setec Astronomy]

The only product I know that claims to add this protection back to the clear is OCW(with continued use)and I believe that is the main part of the patent for OCW.

It's been a while since I've read the patent, but IIRC it wasn't the idea to put a UV inhibitor into a wax/sealant that was the basis of the patent, it was the chemistry that allowed that UV inhibitor to be mixed into an aqueous spray product and adhere to the (car) surface. I just looked it up, the objects of the patent "were accomplished by the discovery of a method of turning emulsions/dispersions into suspensions, by neutralizing the surfactants used in making the emulsion/dispersion."

[Mike Phillips]

I’ve never read anything about the UV bickers/inhibitors “migrating” to the outside?

Could be... but I’ve read a lot and then typed a lot and don’t remember ever reading this?

I have talked to a real chemist and the typed about this on an article I wrote called,

Ceramiclear Paints - Be Careful

You can Google that and add my name and see what I wrote about “migrating” there.

The bigger picture for this topic is - if you want to correct your paint then do it and after that stop putting scratches back into it - at least deep scratches so you don’t have to compound a second time.

Make sense?


:)

[Bruno Soares]

Larry’s latest video with Kevin Brown does mention this migration to the top of the clear. It was the first time I heard about it.

[Calendyr]

What I tell my clients is this: A compound is not something you should be doing as part of the maintenance of the car. If you decide to do it, it should not be repeated. It's a one time process that makes the paint like new but leaves it in a weakens state. Polishes on the other hand al negligeable impact on the paint, so that can be done every year if you want.

I watched the video with Larry and Kevin this afternoon and thought they did a very good job at presenting the facts about paint correction. I am not sure if UV protection migration is a thing or not, but even if it isn't, by removing 20% or the clearcoat during a compounding step, you are removing 20% of the UV protection and making the paint more vulnerable to UV light, thus speeding up the clearcoat failure time.