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Crazing Repair?

Geico266

Geico266

Well Known Member
Is there anything that can be done for windshield crazing? I have a spot on my -10 windscreen about the size of a silver dollar with light crazing. It has been there since the plane was built in 06 and has not gotten worse.

What about the process where they repair cracks with resin under pressure? Is that compatable with our windscreens? :confused:

If someone has an old windscreen I would like to get it and do some testing.
 
Micromesh

Probably very similar to the product Vans sells but ACS carries Micromesh which is designed to remove crazing.

I watched a Micromesh video not long ago - after the first pass it looks like the windshield had been ruined - because your are "sanding" the plexi with a fine (or not so fine depending on how bad the crazing is to start) sandpaper. However, when they finished, the windshield was perfectly clear and all the crazing had been removed.
 
I go with Rick on the micromesh. It can't always get deep old crazing, but it will often get rid of or at least minimize it. I think the regular plexi kits go to 6000 grit, but I got a full set from 1800-12,000 (Malaysian) on ebay for like ten bucks. Works fine & the higher grits make it mo' clear. Downside is you might wind up chasing little scratches all over your 10.
 
Thanks for the input. I really appreciate it. Although sanding my wind screen seems like a bad idea. ;)

Other than distractions from glints of sunlight is there any danger to the wind screen? There seems to have been no progression of the crazing since I have had the plane, but cracks are never a good thing.

Has anyone had to replace the wind screen in an RV-10?
 
buffing out plexi is surprisingly effective...

i have the kit that vans sells and the two foam pads and the backing pad for your drill are very nice... it is a progressive system with 4 grades of abrasive. the two most aggressive are used with the yellow pad and the final two go with the white one. in no time you can take the sanded spot right back to perfectly clear. the deeper the scratch the more sanding needs to be done before you start the buffing process but is is no big deal for small scratches on the outside of the canopy.

as an alternate to going through the 4 grades of abrasive i have found this stuff to be amazing. it is a diminishing abrasive and gets finer and finer as you buff... a bit of water sprayed and it gets finer still.
img0434pv.jpg
 
Practice on scrap first

In AP class I have buffed out a few scratches etc. While it can be done I would suggest scratching then buffing out a test piece before getting anywhere near your windscreen with these products. It takes time and a bit of practice. First time I tried this I ended up buffing a much larger area than needed due to the 'learning process'. My anxiety would have been off the scale if that first attempt had been on my canopy!:eek:
 
Anyone have any thoughts about the liquid resin fix? It seems to me the crazing is deeper than scratches, or is that just an optical illusion?

Putting the area in a vacuum then flooding it with resin makes sense. This works on glass repairs, just not sure about plastic.

I guess I could call the companies that do and and see. Does anyone havhave a broken or scrap wind screen to practice on?
 
Geico266 said:
Anyone have any thoughts about the liquid resin fix? It seems to me the crazing is deeper than scratches, or is that just an optical illusion?

Putting the area in a vacuum then flooding it with resin makes sense. This works on glass repairs, just not sure about plastic.

I guess I could call the companies that do and and see. Does anyone havhave a broken or scrap wind screen to practice on?
Click to expand...

It might be worth talking to these guys, since that's what they do!

http://www.glasstechnics.co.uk/aircraft.html
 
Windscreen

Geico266 said:
Anyone have any thoughts about the liquid resin fix? It seems to me the crazing is deeper than scratches, or is that just an optical illusion?

Putting the area in a vacuum then flooding it with resin makes sense. This works on glass repairs, just not sure about plastic.

I guess I could call the companies that do and and see. Does anyone havhave a broken or scrap wind screen to practice on?
Click to expand...


For years I polished GA windows out for a living, out of the hundreds of windows I sanded and polished I never ran across a plexiglas window I could not repair. Most crazing always creates a optical illusion. A great kit for the first timer would be the micro mesh kit.

Good luck

Ed
 
I finally decided to try and remove some lite scratches in the side windows where passenger headsets rubbed. I used a Meguiers Headlight Restorer kit. It has 4 sanding pads, a buffing pad, and polishing cream.

I practiced on my wife's headlights first earning brownie points! ;) They were yellow and nasty, now they are crystal clear. Needless to say the kit worked great on the head lights so I moved onto the plane!

There is something very unnerving about taking sand paper to airplane windows. :eek: But with a little patience and elbow grease I removed lite scratches and a 3"x1" crazing area on the windscreen! I didn't get it all out, but 75% of the crazing is gone! Scratches are all gone!

My Micromesh kit is on the way to do the entire windscreen, but I wanted to post the success I had with a Meguiers Headlight Restoration kit for light scratches and blemishes. :D


Carry on. ;)
 
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this would be a great place for "before and after" pics.

I have a couple hazy areas on my rear window. It looks like little fogged up area. Pretty sure it came from the paint process getting through the masking paper. Anyone else have an are a like that buffed out?
 
[email protected] said:
as an alternate to going through the 4 grades of abrasive i have found this stuff to be amazing. it is a diminishing abrasive and gets finer and finer as you buff... a bit of water sprayed and it gets finer still.
img0434pv.jpg
Click to expand...

This is also the stuff that Grady at GLO recommends for buffing paint. Pricey, but it works great.

Jim Berry
RV-10
 
hydroguy2 said:
this would be a great place for "before and after" pics.

I have a couple hazy areas on my rear window. It looks like little fogged up area. Pretty sure it came from the paint process getting through the masking paper. Anyone else have an are a like that buffed out?
Click to expand...

Very hard to capture micro scratches with a camera. ;)

That would be a great project for the buffing system. I just buffed out an entire 8 canopy inside and out. Made a HUGE difference. Took 4 hours.
 
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Geico266 said:
This kit worked good for me as I did the entire canopy. The second to the last step I did by hand to eliminate swirl marks.

http://www.aircraftspruce.com/catalog/cspages/Micromesh.php?clickkey=72629
Click to expand...

Makes me wonder why they are specifically calling this a Polycarbonate restoration kit. Vans canopies are acrylic correct? I guess it seemed to work for you, but still makes me curious. It has been my understanding that polycarbonates are easier to scratch than acrylic, so maybe this poly kit has finer grade materials?
 
hydroguy2 said:
this would be a great place for "before and after" pics.

I have a couple hazy areas on my rear window. It looks like little fogged up area. Pretty sure it came from the paint process getting through the masking paper...
Click to expand...

I did some aviation design with acrylics and polycarbonates a few years back. The Materials and Process guys would not allow anything containing Ketones (like acetone) to touch the plastic because it can cause crazing.
 
Crazing vs. Surface Scratches?

I've always thought of "crazing" as the very fine subsurface spiderweb like cracking that occurs as a result of exposure to chemicals, UV degradation, or as stress fractures from excessive bending forces. I'd been told that this cannot be "polished" out.

Am I talking about the same thing your are?

That being said, I used the micro-mesh kits to repair pitted chin bubbles on our old Hueys back in the day. It takes a LOT of patience, but it does work!
 
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