Over the weekend I was messing around with my spare helmet and decided to see if I could remove the scratches that make it almost impossible to see out the visor.  I wetsanded and polish and the scratches are mostly gone yet the shield is hazy and just as impossible to see out of now just for different reasons.  Can anyone suggest what I might have done?  This was on a stock face shield from an HJC CL-14 helmet.

Steps I followed in this order:
1. 1000 grit wetsand
2. 1500 grit wetsand
3. 2000 grit wetsand
4. Turtle wax polishing compound
5. Scratch X Swirl Remover
6. I also used some kind of Turtle wax stuff that is safe on paint/clear coats to bring back shine and remove dullness but I can't recall the name

Quote from: utgunslinger13 on March 28, 2011, 12:14:12 PM
Can anyone suggest what I might have done? 

Yep. You skipped the "spend $15 on a new shield" step. 

Quote from: murf425 on March 28, 2011, 12:24:21 PM

Quote from: utgunslinger13 on March 28, 2011, 12:14:12 PM
Can anyone suggest what I might have done?

Yep. You skipped the "spend $15 on a new shield" step. 

Well, all supplies were sitting in the garage so I figured I'd spend an hour on Saturday to see if I could clean this one up. lol  Now its just got me PO'd that the scratches are gone but I still can't see through it!

I have had some success in the past removing scratches from perspex and similar materials using simple metal polish, like "Silvo", "Brasso" or "Dura-Glit"

Quote from: utgunslinger13 on March 28, 2011, 12:14:12 PM
Can anyone suggest what I might have done?

You replaced the maybe 100 scratches you had with millions of very small scratches.  That's what sand paper will do to a clear surface.

ive used jewelers rouge and my foredom handpiece to polish things like this out, ( workes great on hazy headlights as well. will get it almost perfect, BUT it will never be perfect. visible yes, and usable but not right.

Quote2000 grit wetsand

Not nearly fine enough for polishing clear plastic.

IMHO, you need use something like 12000 grit polishing pad minimum, before using polishing compound.

120,000 grit compound? Awesome, sign me up for that stuff.  

What you did should have worked. I use a similar procedure to polish watch crystals, which are the same material (I thought) The polishing compound that you finished with is the likely culprit. Try a couple of others (pick one):

1) automotive cleaner wax
2) toothpaste
3) plastic polish, automotive

Edit

I have the same issues too. I got another Shoei visor off someone here with in 24 hours of having it on hit another massive bug! Scratch right over the eye! Had a pinlock too and Shoei are about $35 not $15!

Mary

Maybe y'all shold come to Australia where an ARAI shield is $99  - then you wouldn't complain about a $35 or $20 or what ever else $$$ shield.

What you did wrong was try to salvage a cheap shield. Probably spent more time doing it then what it would have cost you to buy a new shield from earned money for the same time.

Michael

Quote from: noiseguy on March 28, 2011, 09:31:00 PM
120,000 grit compound? Awesome, sign me up for that stuff. 

Not 120,000 - 12 000

Like in this kit http://www.ptreeusa.com/microMesh.htm

Quote from: paulc86 on March 28, 2011, 05:11:35 PM
That's what sand paper will do to a clear surface.

Yep. Like after my wedding, when I tasked one of my groomsmen with getting all the window paint and crap off of my BRAND NEW car while we were on our honeymoon. He let it sit a few days, 'til it was so dried that a pressure washer wouldn't even take it off, and then decided to use SANDPAPER to get it off the windshield.

I could've killed him. 

Polishing glass and plastic are entirely different things. Glass actually requires the high-numbered-grit abrasive. Plastic doesn't.

Before:



After:



Procedure, which doesn't require high polish; I've finished crystals with 2000 grit and polished, and they looked great when done:

http://en.wikibooks.org/wiki/Budget_Watch_Collecting/Plastic_crystal_polishing

The point of departure is that watch crystals (plastic ones) are acrylic, and visors are polycarbonate (which resists shatter), but polycarbonate is also used in car headlamp, and can be polished the same way.

Bottom line, it's not fair to criticize the attempt. It should have reasonably been expected to work. And don't even get me started on what constitutes a waste of time vs $$$. That's another conversation entirely. 

My 2 cents: Next time, do a trial in a small spot that you wouldn't normally see / look through before doing the entire thing.

I would just try to wax it to fill in the scratch, and if that didn't work then I would buy a new shield.

Quote from: noiseguy on March 29, 2011, 07:43:44 AM
Polishing glass and plastic are entirely different things. Glass actually requires the high-numbered-grit abrasive. Plastic doesn't.

Before:



After:



Procedure, which doesn't require high polish; I've finished crystals with 2000 grit and polished, and they looked great when done:

http://en.wikibooks.org/wiki/Budget_Watch_Collecting/Plastic_crystal_polishing

The point of departure is that watch crystals (plastic ones) are acrylic, and visors are polycarbonate (which resists shatter), but polycarbonate is also used in car headlamp, and can be polished the same way.

Bottom line, it's not fair to criticize the attempt. It should have reasonably been expected to work. And don't even get me started on what constitutes a waste of time vs $$$. That's another conversation entirely. 

My 2 cents: Next time, do a trial in a small spot that you wouldn't normally see / look through before doing the entire thing.

Thanks for the helpful input.  Seems most people around here are to quick to just buy new parts without even attempting to fix what could be fixed.  With a 5 month old baby, I don't have the expendable cash I used to and I can't justify a new facesheild for a spare helmet that will probably spend a majority of its life sitting in the garage.

After reading your posting and link you provided, I'm wondering if the cause could be that I sanding the same direction for all grits of sandpaper? 

I don't think the sanding's your problem.

Were I to attempt this, I'd use wet/dry paper wet over a mirror glaze foam block (used for body work.) Just folded paper is probably OK. And I would sand in circles. And I wouldn't bother with anything higher than 2000 grit.

I'd sprinkle some water on the visor and hit it with polish by hand. Maybe a lambwool applicator mounted to a grinder/polisher? Seems like overkill.

I think the problem is that there's some sort of hardened coating they use on the visor that doesn't polish (easily), according to some ppl that have tried polishing these. Either that or you're not getting enough pressure/velocity on the shield during the polish operation.

Try some other products for polishing and/or more elbow grease. If sanding were inadequate and the polish working, the shield would look scratched up, i.e. like it had been through a sandstorm. The fact that it looks "hazy" implies that the polish operation isn't working.

Some guys talking about this. They recommend toothpaste as well for polishing:
http://www.tlzone.net/forums/open-forum/99676-smoothing-scratches-helmet-visors-q.html

What brand visor are you working on? This is something where cheaper is probably better (for your purposes.)

yes. if i werent at shop and had my jewelers rouge, id use toothpaste as well. WHITE toothpaste aka plain. not hte mixed. ive used it polishing heatsinks for a computer. when lappting them. works pretty good. ive not ever got a visor to ever be as good as new mind you, BUT have got it to be usable

I made another attempt last night with a little more pressure with the sand paper and I noticed something while sanding.  There seems to be a film of some sort on the inside and outside of the shield.  The more pressure applied with the 1000 grit sandpaper removed this coating.  I removed a section about 3X3 inside and out, then moved to the polishing and it came out almost perfect!

I'm not sure what that film was that I sanded off but it seems that it was the culprit because as soon as I sanded it off and polished again the haze was gone and the shield looks 10000 times better!

Quote from: utgunslinger13 on March 30, 2011, 07:15:47 AM
I made another attempt last night with a little more pressure with the sand paper and I noticed something while sanding.  There seems to be a film of some sort on the inside and outside of the shield.  The more pressure applied with the 1000 grit sandpaper removed this coating.  I removed a section about 3X3 inside and out, then moved to the polishing and it came out almost perfect!

I'm not sure what that film was that I sanded off but it seems that it was the culprit because as soon as I sanded it off and polished again the haze was gone and the shield looks 10000 times better!

OK, that would be the protective coating I've heard referred to. Apparently harder than the base material.

Rather than continue with sanding harder with 1000 grit, I'd try moving to 600 or 420 grit as a first pass to remove the coating.

I expect that the shield will now scratch easier in the future... at this point, doesn't really matter.