Sealer or no sealer

[Brent123]

The Delta Kits Coat & Catalyst is now on our website under "Headlight Restoration".
The cost is $74.00 for the combination package, each bottle is 8 ounces. This can only by shipped UPS Ground.

[t4k]

The Delta Kits Coat & Catalyst is now on our website under "Headlight Restoration".
The cost is $74.00 for the combination package, each bottle is 8 ounces. This can only by shipped UPS Ground.

Ok....thanks Tammy.

[ray6]

I know you headlight restoration guys and gals have covered this to some degree in the past, but it seems to me that most of you believe that it is very important to use a sealer after the headlight has been sanded. Are any of you adamantly opposed to the use of a sealer?

I have tested a few different systems to see what was the best on the market, and several other systems that I am still planning to test as time allows, but I am still confused about something.

This weekend I saw several demonstrations with varying results, and spoke to at least 6 different companies that sell headlight restoration products. Some say there is no need to use a sealer, and some say a sealer is necessary to get maximum protection. Some say if you use a sealer it needs to be solvent based, and others claim that only a water based sealer should ever be used on a headlight. I am now beginning to understand how truly confusing it is to new windshield repair technicians when they begin calling windshield repair suppliers. In fact, we had a number of people come by our booth that had been told it was impossible to fill a tight star break without drilling and/or impossible to completely fill a break without using vacuum as the first step. Seeing is believing, so it is easy to dispel those myths about windshield repair, but when it comes to how long a headlight will stay clear after restoration, I can't seem to find any proof.

There were two companies at the Mobile Tech Expo that did not recommend sealers, and one of those produced the best looking headlight restoration that I have ever seen. These are also two companies that I have been told supply many of the aircraft window restoration specialists. However "if" it is true that without a sealer the lens will yellow again within a few months, the cosmetic finish may not be as important as how long the finish lasts, at least for headlights.

For you guys that do use sealers, what do you think about spray on sealers vs paint on sealers?

Have any of you restored a headlight and then left it out in the weather for a few years to see what happens? If so, what did you use, and what were the results. Since some headlights seem to yellow faster right from the factory, I'm not sure even a test like that will be all that good of a test unless several products were tested at the same time on exactly the same make and model of headlight, but it would be a start.

I would like to endorse a headlight restoration product for my customers, but cannot do so unless I think it is the very best, and there are still too many unanswered questions for me.

I know a lot of you like the Develup system, so I was very interested in talking to those folks, but I went by their booth and no one seemed all that interested in talking to me. Two guys were sitting behind the table for about 10 minutes as I looked over their literature and watched their video, but neither made any attempt to find out what I wanted, so I got bored and moved on.

I would appreciate any thoughts from all of you experts out there, especially if you can back up your opinion with personal longevity testing.

Brent-
The protective coat applied by the headlight manufacturer was applied to protect the polycarbonate from moisture and ultraviolet exposure. It is a silicone based solvent applied by spray and it is very thin. This coating contains UV adsorption materials (mostly from General Electric) and a sealer.

The Department of Transportation requires headlights to meet certain requirements as far as UV protection and moisture. The test standard is complex, but basically states that there should be no serious deterioration with 24 months of severe UV/moisture exposure. That's not much. This protective coat is expensive; estimated to be about $1200 for 5 gallons. This is one reason why the manufacturer applies a very thin coat.

Since headlight restoration removes this protective coating, the exposed polycarbonate will deteriorate. How much and how fast is dependant on enviromental conditions.

Our tests on polycarbonate coupons show measurable deterioration within 60 to 120 days, becoming visible in 4 to 6 months. It varies by different polycarbonate formulations.

If a protective coating is not needed, why do manufacturers put it on in the first place? Raw polycarbonate is very porous and cannot withstand UV radiation.

We don't remove the old coating with sandpaper, instead we remove only the damaged coating (oxidized) chemically. We then apply a new protective coating. It is solvent based so it binds well with any undamaged material still on the headlight and with the underlying polycarbonate. The new coating is urethane based with UV inhibitors and leveling compounds which actually smooth out some defects and produce a clearer restoration. Although our protective coat is 1 part, it is probably very similar to Devlup's, although I have never used theirs to compare. We now have 2 test lamps with over 22 months exposure (San Francisco bay area) and look the same, although there is some measurable deterioation but not detectable by eye.

I think you should look at headlight restoration as a two step method; the old coat removal/sanding damage removal/polish, and the new protective coat application. They're really two separate steps.

Regards,

Ray6

[Brent Deines]

Wow Ray, you really missed a lot of my posts along the way. I agree with you for the most part, and I have stated that our testing has also found the a protective coating will help keep the lens clear much longer than an untreated lens, which is why we include protective coating with every professional headlight restoration system we sell.

Actually I don't think $1200 for 5 gallons is too much to pay to put the factory sealant back on the lens, in fact, I think that is a bargain. The fact that you state that it is silicone based is very interesting, as a coating manufacturer told me something quite different, and in fact said that silicone should not be used. I'm not arguing with you on this, just a little confused. Are you a chemist? Did you get this information straight from the manufacturer of company who produces the OEM coating?

The post of mine you pulled up was from quite some time ago and I have learned a great deal since then, but I will say that there are still several theories about what is applied from the factory, how it is applied, and if it is all done in the same way. Please tell us your source for the information you provided so it can be validated. So far I have heard a lot of people make statements of complete authority, but have not seen any verifiable data to back it up. It sounds like you may be the one to set the record straight once and for all, perhaps with a document from a headlight manufacturing company? Posting the DOT document to verify their testing procedures would also be helpful.

I have consulted lots of experts and have yet to find two that agree, so the documentation you provide will no doubt be greatly appreciated by many.

[ray6]

Wow Ray, you really missed a lot of my posts along the way. I agree with you for the most part, and I have stated that our testing has also found the a protective coating will help keep the lens clear much longer than an untreated lens, which is why we include protective coating with every professional headlight restoration system we sell.

Actually I don't think $1200 for 5 gallons is too much to pay to put the factory sealant back on the lens, in fact, I think that is a bargain. The fact that you state that it is silicone based is very interesting, as a coating manufacturer told me something quite different, and in fact said that silicone should not be used. I'm not arguing with you on this, just a little confused. Are you a chemist? Did you get this information straight from the manufacturer of company who produces the OEM coating?

The post of mine you pulled up was from quite some time ago and I have learned a great deal since then, but I will say that there are still several theories about what is applied from the factory, how it is applied, and if it is all done in the same way. Please tell us your source for the information you provided so it can be validated. So far I have heard a lot of people make statements of complete authority, but have not seen any verifiable data to back it up. It sounds like you may be the one to set the record straight once and for all, perhaps with a document from a headlight manufacturing company? Posting the DOT document to verify their testing procedures would also be helpful.

I have consulted lots of experts and have yet to find two that agree, so the documentation you provide will no doubt be greatly appreciated by many.

Brent-I am not a chemist but we use the services of a chemist from time to time, especially in the beginning. The information was derived by our chemist researching the manufacturer's data of suppliers to the headlight industry and through industry contacts. He used to work for General Electric and worked in the O.E.M. (UV adsorption) part.

It's been awhile, but I can probably dig up some reference data. Much of it is online and can be found by examining DOT regulations as they apply to headlights.

The data we used is over 2 years old and it may be that silicone is no longer used since it doesn't work all that well. It looks like some manufacturers are using better grade materials and why some headlights are difficult to clear.

Rob, our chemist, says the average coating on pre-2000 Detroit headlights was between 20 and 40 microns. A human hair is 100 microns, so I guess 5 gallons would go a long way.

[ray6]

Wow Ray, you really missed a lot of my posts along the way. I agree with you for the most part, and I have stated that our testing has also found the a protective coating will help keep the lens clear much longer than an untreated lens, which is why we include protective coating with every professional headlight restoration system we sell.

Actually I don't think $1200 for 5 gallons is too much to pay to put the factory sealant back on the lens, in fact, I think that is a bargain. The fact that you state that it is silicone based is very interesting, as a coating manufacturer told me something quite different, and in fact said that silicone should not be used. I'm not arguing with you on this, just a little confused. Are you a chemist? Did you get this information straight from the manufacturer of company who produces the OEM coating?

The post of mine you pulled up was from quite some time ago and I have learned a great deal since then, but I will say that there are still several theories about what is applied from the factory, how it is applied, and if it is all done in the same way. Please tell us your source for the information you provided so it can be validated. So far I have heard a lot of people make statements of complete authority, but have not seen any verifiable data to back it up. It sounds like you may be the one to set the record straight once and for all, perhaps with a document from a headlight manufacturing company? Posting the DOT document to verify their testing procedures would also be helpful.

I have consulted lots of experts and have yet to find two that agree, so the documentation you provide will no doubt be greatly appreciated by many.

Brent- I found 1 part of the DOT/SAE test procedure we started with. You have to follow each listed link to get the whole picture. And I was wrong, the exposure test is 3 years, not 2. Transmission capability (measured with a photometer) less than 70% fails the test.

Some additional info can be had by searching for UV adsorption materials from General Electric. They make direct reference to manufacturers of headlight protective coating manufacturers and how the amount of material affects UV degredation.

Ray6

[Jbrodie]

I have been doing headlight restoration for a few months. I'm probably making more work out of it than i should but i've been wet sanding with 600 grit if realy heavy oxidation than going 1000 grit and finish it off with 2000 grit unless the headlight is mild yellow no oxidation but the customer wants it looking new I'll use a polish that i recieved from my first kit (liquid Resin) i do it all by hand with the orbiter backing just no orbiter so i have more control of the sand paper and polisher. I'm thinking of purchasing a small orbiter for the polishing but still wet sand by hand. When I'm finished the sanding to prevent over spraying I use vasoline keeping it off the lense just around the out side of the lense and it takes less time to set up than taping and papertowels. I seal it with ReNuLite, I get the small can does 2 1/2 cars it never has let me down, makes the lense look factory new. I like the ReLuLite cause it's a spray on and coats the lens I just keep it covered with a moving blaket over the area I'm working on for a few minutes to prevet premature UV exposure and givethe sealer a chance to level out and than take the blanket and give it full sun exposure.

[harrellbenjamin]

Spraying is a waste of time and $$$$$$$$... Just buy the 2 part sealer from Dvelup/Delta Kits and wipe on.It flows out and lays just as flat and glossy as any spray on.No streaks on runs when applied properly.No masking etc. and can mix -wipe and walk away in about 2 Min's.Just clean lens with rubbing alcohal before application.I live in the deep south with real high UV factors and fix them all the time for 3 plus years.The sealer is good ,fast and lasts. JMHO

[ray6]

Not only does a good sealer protect the base polycarbonate, it tends to fill in shallow scratches left by sanding. This is why the headlight looks better after applying the sealer.