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Repairing cracks in windscreen - is it worth it?

Over the Christmas holiday a stone thrown up by a lorry wheel made a small (2mm) crack in my windshield.

My wife has been telling me I need to take it to Autoglass to get it repaired otherwise the crack is likely to spread. Unsurprisingly, her alarmist view on this is largely derived from the Autoglass TV adverts.

The car is 8 years old and has done just under 100K miles. It has maybe another two years of life left in it before I flog it for peanuts, so I don't really want to spend any money on it unless it is absolutely necessary.

My question is:

--Will I fail an M.O.T because I have an almost imperceptible 2mm crack in the windshield glass?

--Is the crack likely to spread? (in the 6 weeks so far there is no evidence for this)

--Is the Autoglass crack repair service, like so many other motoring products advertised on TV, "snakeoil"?

Reply to
Stewart Gardiner
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A crack must be 10mm diameter or bigger before it is a MOT issue.

Maybe, maybe not. I picked up a stone chip right behind the rear view mirror two weeks after I picked up my current car. 3 years later, it's still there and it's still the same size.

Reply to
Grant Mason

If you have comprehensive insurance, this will almost certainly cover the repair with no excess and no 'claim' counted against you, so if the repair is free (to you) I would go for it. A 2mm crack is fine for MOT, larger cracks can fail, the allowable size depends on the site of the damage. The repairs certainly work, I have a stone impact crack in my screen nearly 10mm long, the Autoglass repair was free (to me), the damage is now invisible unless you look close-up and it has stopped any propagation of the crack (2

1/2 years old.) It's impossible to say whether your crack will propagate or not.
Reply to
Bob Davis

Depends where it is - if it's in the windscreen wiper arc in front of the driver the tester may have something to say about. I think there is a minimum size though - anyone??

I think you're lucky so far, but there is no guarantee it will stay stable. One pothole too many can start a fracture from this point, and then you may be stuffed. I lost a Manta windscreen this way by ignoring it for too long. A 3mm crack at the top edge eventually became an MoT busting 6 inches long some 8 months later.

I think the repairs involve repairing the laminate that has been lost above the glass, with an epoxy resin.

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sell a DIY kit that works for a few quid - requires a bit of patience and doesn't necessarily make an invisible repair, but this sorted out the windscreen on a Jag XJS I had, for the 2 years I had it.

-- Ken Davidson DocDelete

Reply to
DocDelete

No. 10 mm is the size.

Could do but remember the windscreen is laminated. It'll just be the outer layer that goes so no problem from a safety issue.

IMO yes. I've seen stonechip "craters" repaired and they're still perfectly visible.

Reply to
Conor

Is it a chip or a crack? A crack will spread, rendering the screen useless. They can prevent this by drilling a small hole at each end before repairing it. A chip won't spread but the glass around it will turn milky as water gets inside the laminate. Once this happens they will not repair it, so get it done soon if you're going to. Like someone said, the repairs aren't invisible but they are an improvement and stop it getting worse.

On fully comp insurance you can usually get spot repairs done free (they'll come out to you, too) or a new screen for £50, your NCD not affected. If you were keeping the car a new screen would be well worth it - it's amazing, especially at night, and you have to keep touching to make sure it's there.

Reply to
Dan Buchan

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