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dcgocd
03-11-2013, 09:02 PM
The next purchase I am considering is a paint thickness gauge, I have done corrections on a couple vehicles that have corrected to 95 %.

There were some scratches that I was reluctant to take out because of fear of going through the clearcoat.I feel like if I made a couple more passes ,I probably could have removed them

I am using a seat of the pants approach and would love to take out some of the heavier scratches if possible to get closer to a perfect correction if possible.

Other than checking first with a paint thickness gauge, I see no other way of doing this.

I know some of you guys with more experience have run into this issue,any advice would be appreciated.

:buffing:

Scott@IncrediblyDetailed
03-11-2013, 10:11 PM
The only way to know for sure is a gauge. It's a good investment because its much cheaper than having a car painted and the headache associated.

Pureshine
03-11-2013, 10:52 PM
If you can get you finger into it most likely it has to be repainted. A paint gauge will let you no how much clear is left so you can try and wet and it to help tone down the scratch. Do you have picture of the scratch?

zmcgovern45
03-12-2013, 11:22 AM
If you can get you finger into it most likely it has to be repainted. A paint gauge will let you no how much clear is left so you can try and wet and it to help tone down the scratch. Do you have picture of the scratch?

This is misleading information... most paint gauges available (price-wise) to the average consumer do NOT indicate the amount of remaining clear coat. They simply measure the entire thickness between the bare metal and the surface of the paint. So, assuming BC/CC scenario, the PTG reading will provide you the thickness of both the BC and CC. There is no way to determine how much of that reading is actual CC and how much is BC, so there is still some risk involved. A PTG will allow you to make more educated decisions, however, because you can usually make the assumption that a larger reading means there is more CC to work with (note: this assumption may not be true 100% of the time).

If it is a scratch that can be corrected with another pass with a cutting pad and compound, it is highly unlikely that you will ruin any clear coat (with a DA machine!). However, if you need to do some sanding - it is always nice to have some reassurance that a PTG may provide. The general rule of thumb, as previously stated, is that if it catches a fingernail, you cannot remove it with buffing.

dcgocd
03-12-2013, 03:00 PM
This is misleading information... most paint gauges available (price-wise) to the average consumer do NOT indicate the amount of remaining clear coat. They simply measure the entire thickness between the bare metal and the surface of the paint. So, assuming BC/CC scenario, the PTG reading will provide you the thickness of both the BC and CC. There is no way to determine how much of that reading is actual CC and how much is BC, so there is still some risk involved. A PTG will allow you to make more educated decisions, however, because you can usually make the assumption that a larger reading means there is more CC to work with (note: this assumption may not be true 100% of the time).

If it is a scratch that can be corrected with another pass with a cutting pad and compound, it is highly unlikely that you will ruin any clear coat (with a DA machine!). However, if you need to do some sanding - it is always nice to have some reassurance that a PTG may provide. The general rule of thumb, as previously stated, is that if it catches a fingernail, you cannot remove it with buffing.

Good info,I was reading up on paint depth gauges earlier today and found out exactly
what you referred to about giving you the overall paint thickness and not the clearcoat actual thickness

So basicly it is a shot in the dark, and somewhat of a gamble anytime you take a compound or a polisher to a vehicle

I know I saw somewhere where after using M105 the paint thickness was checked and it really showed very nominal changes in the thickness from a prior reading.

On the pearl white Acura I just finished there were very heavy scratches on the hood ,roof and trunk

I actually ended up using a 5.5" LC flat yellow cut pad and M105. I did 2 applications of the M105 with 6 section passes each followed by 1 application of M205 on an orange flat pad

I feel like I might be able to take these scratches out with a couple more passes with M105 and a cut pad ,but didnt want to gamble by doing additional passes. So I chose the conservative route.

The 1997 Acura was bought used and I had no way of knowing if it had been polished out in its previous life

The scratches that were left appeared to be deeper by looking at them but you could not snag a fingernail on them.

Leaving any scratches at all goes against evry fiber of my being,but its better than going through the clearcoat.

Lowejackson
03-12-2013, 03:39 PM
...Leaving any scratches at all goes against evry fiber of my being,but its better than going through the clearcoat.


..and cheaper

zmcgovern45
03-12-2013, 04:34 PM
...I know I saw somewhere where after using M105 the paint thickness was checked and it really showed very nominal changes in the thickness from a prior reading....



Do you mean very minimal changes? If so, that is very likely. Compounding and polishing paint is not meant to remove much clear coat - that would force us to weigh the pros and cons of leaving swirls and scratches vs. correcting much more heavily that we do. A vehicle can (usually) withstand a fair amount of correction throughout it's life. You just need to realize, that in the even that there is very little clear coat remaining, it is possible to buff away the remaining clear coat with a DA machine. Being able to measure the overall thickness with a PTG helps you to determine your possible risk better than simply guessing.

psynx
03-12-2013, 04:57 PM
This is misleading information... most paint gauges available (price-wise) to the average consumer do NOT indicate the amount of remaining clear coat. They simply measure the entire thickness between the bare metal and the surface of the paint. So, assuming BC/CC scenario, the PTG reading will provide you the thickness of both the BC and CC. There is no way to determine how much of that reading is actual CC and how much is BC, so there is still some risk involved. A PTG will allow you to make more educated decisions, however, because you can usually make the assumption that a larger reading means there is more CC to work with (note: this assumption may not be true 100% of the time).

If it is a scratch that can be corrected with another pass with a cutting pad and compound, it is highly unlikely that you will ruin any clear coat (with a DA machine!). However, if you need to do some sanding - it is always nice to have some reassurance that a PTG may provide. The general rule of thumb, as previously stated, is that if it catches a fingernail, you cannot remove it with buffing.

:iagree: yes i wanna gonna correct him until i read your post, great job on clarifying that

dcgocd
03-12-2013, 06:24 PM
Thanks Guys, Very informative info, Looks like I will be purchasing a PTG in the near future.

Also,some very impressive web sites for your businesses ! Its great to be able to get
input so quickly from experts ,sure accelerates the learning curve.