3M headlight restorer - what am I doing wrong?

[Pseudo Nim]

Hi all,

 

So I'm trying to restore my headlight using the 3M restorer, except I think I'm going from bad to worse. I first tried with a random orbiter and the P500 discs, but that didn't go so well - I scratched up the lens more than I restored it. So I aborted and restarted using a drill. But I have these "hot spots" on the lens that I just can't seem to get rid of (see picture). What am I doing wrong? I am running at the prescribed 1,200 rpm or so (my drill has a speed limiter, is a 2,400 rpm max drill, and I have it set at about 50%). I am not exercising excessive pressure. I'm also making sure I don't stay in one spot for too long a time (if I had to describe my process, a single pass takes me about 3 seconds from one end of the lens to the other). The lens doesn't really "frost up" as 3M shows, and overall, the process doesn't seem to be quite working - and my headlight is progressively getting worse. :blush:

 

Any advice, or should I start shopping for a new headlight?

 

 

 

[KevinH90]

I think you will be OK.  It appears that your problem may be that you haven't totally removed the existing UV outer coating. I used a combination of the Sylvania and 3M kits when I restored my headlights.  The advantages of the Sylvania kit are that it includes a solution that removes the existing UV layer which makes the headlight easier to sand and it has a protective coating that you put on at the end that smooths the surface and makes it shine.  I liked the 3M kit because it had the drill attachment. 

 

Here's the thread in which I discussed my process: http://986forum.com/forums/general-discussions/54697-advice-used-litronics.html

[Pseudo Nim]

I think you will be OK.  It appears that your problem may be that you haven't totally removed the existing UV outer coating. I used a combination of the Sylvania and 3M kits when I restored my headlights.  The advantages of the Sylvania kit are that it includes a solution that removes the existing UV layer which makes the headlight easier to sand and it has a protective coating that you put on at the end that smooths the surface and makes it shine.  I liked the 3M kit because it had the drill attachment. 

 

Here's the thread in which I discussed my process: http://986forum.com/forums/general-discussions/54697-advice-used-litronics.html

 

Thanks. What's throwing me off is the lens won't cloud or become frosty at all, no matter how much I sand it ... maybe I need a stronger grit sandpaper?... I've gone over it a number of times with the P500, and it hasn't begun to frost up at all except for a few places.

[KevinH90]

I used a quarter-sheet finishing sander and started with 320 grit. I progressed through 600, 1000 and 2000. Then I used a 3000 grit finishing disk in the 3M kit and then polished with the 3M compound.

 

Some of the feedback I received was that 320 may have been unnecessary and that 400 grit would have been a good place to start.

[Pseudo Nim]

I used a quarter-sheet finishing sander and started with 320 grit. I progressed through 600, 1000 and 2000. Then I used a 3000 grit finishing disk in the 3M kit and then polished with the 3M compound.

 

Some of the feedback I received was that 320 may have been unnecessary and that 400 grit would have been a good place to start.

Yeah I found the thread where you talked about it and where people suggested 320 may have been excessive, hehe.

 

In my case, I'm wondering if I should go to a 400, since the 500 is doing absolutely nothing. Did you water the lens at every step? I'm not watering it at all, since the 3M manual never tells me to do it, but it seems like some people are recommending it?...

[rockhouse66]

I think you missed the part in KevinH90s where he noted that the Sylvania kit includes a solvent for the existing coating.  Worked like a champ for me.

[Pseudo Nim]

I think you missed the part in KevinH90s where he noted that the Sylvania kit includes a solvent for the existing coating.  Worked like a champ for me.

 

Ahh yeah I did miss that. Guess I have to find a way to source that kit in Japan ... I think I should stop all work on the headlight as is and try to get the Sylvania kit, see how that goes.

[KevinH90]

It has been a while since I did my project.  I think I may have wet sanded when I was using the very fine grits.

 

As Rockhouse suggests, try to obtain the Sylvania solvent before you become too aggressive with the sanding. 

[Youri Ko]

I may chime in as I just did mine :

 

They had this terrible "clear coat" applied over them which baked in the sun and made the polishing process harder as I had to sand that one off before actually sanding the lens.

All work was done using Griot's DA polisher and wet sanding disks. Lowest I went was 600 and if it was not for that clear coat, I would not go lower than 1000 personally.

Never heard of that solvent people mention, wander if that would remove the clear coat I had on them and make job easier.

 

https://lh3.googleusercontent.com/HogBhCsv0vCMV86gO-Xpo0PTf9nQccbfWjYaqVFhFttHVd0LDjDd5Izn06Hyk75qeNMMrhmE-bo2Ga_G5xOU7v2pBt4p_knBhrOukzcUsk-wD5db5Au4ZB8JMYxrIh9dGzCoeGeEdK_Dwru21pN5iz2JxOngXuM7E_-Fk9Pnc2TsFgYdgEkrQL-ZVCiBS4yBssAjwGxKp1WNrf9Am2DceqNF_bsL0Ve0Tz0s1YZ0Fn5C3ySzyx6HtxvmXxZvc6wggg_uT8Rzjw0H7Glw0fqxFiqNEmNW1CmI3g3zKiqQbjPHYS3bl4GvkJfFcha0WJbrKFcrpNfmV_ru4wFqI_Rp0IO5uLPnV9Bzrp3gfnGofsjhU6KAsRyLnDD3NosmiuZi6DKhpBRBGaqA2Fcq21CcEwdNGxSaIw_6jpCvThrdjXnPPkkqOq3s3IluoRC3EwiSTmFYV_DW8YhpNe8U_skO-Zm6me-SF0CSO3o5TaYB3rUqtLQXagg0wQw8YMIHRqskHv8ap53HsWqDY7FzDK4KCFX31ZPQ5aZ1P7gatybs589zhi8Ocs3As8t3ySeEUXHXy-T-=w1152-h864-no

Edited January 15, 2016 by Youri Ko