Does windshield rock chip repair prevent crack propagation?

>A wrong move with the bit, and kablammo, the entire windshield will
>disintegrate in a second or less, into a kazillion bits that will take

>a week to clean up. So there IS some *risk* involved

Auto windshields are laminated, like I said, and have a
sticky semi-liquid clear goop between the layers to hold the thing
together if it gets busted. It won't explode like side or rear windows.
In replacing a windshield, the fastest way to get the old one out is to
put a heavy blanket on the hood in front of the windshield, sit inside
in the middle of the front seat, and boot the thing out with both feet.
It breaks and folds up like cardboard.

Dan

On 7 Mar 2005 20:25:58 -0800, wrote:

>>A wrong move with the bit, and kablammo, the entire windshield will
>>disintegrate in a second or less, into a kazillion bits that will take
>
>>a week to clean up. So there IS some *risk* involved
>
> Auto windshields are laminated, like I said, and have a
>sticky semi-liquid clear goop between the layers to hold the thing
>together if it gets busted. It won't explode like side or rear windows.
>In replacing a windshield, the fastest way to get the old one out is to
>put a heavy blanket on the hood in front of the windshield, sit inside
>in the middle of the front seat, and boot the thing out with both feet.
>It breaks and folds up like cardboard.
>
> Dan

This is the easy way, BEFORE spending a lot of money on "new"

Go to junkyard with carbide tipped drill bit and portable drill. And
small center punch and little hammer to tap away window glaze so bit
can take hold.

TRY THE TECHNIQUE ON A JUNYARD CAR.

If successful, go home and do it to -your- car.

If not, walk away a wiser person.

What is wrong with this plan? Something magic about it we can't put
our finger on? Forbidden fruit? Zeus gonna throw a lightening bolt
at us if we try this or something?

NOTHING VENTURED NOTHING GAINED.

In the time we've been bull****ting about this, the job could already
be finished by now.

Lg

mike wrote:
> Got a nasty rock chip in my windshield. Three impact divots connected
> by a crack about 1.5" long. Short star pattern at each impact.
> It's well out of the normal field of view, but I'm very concerned about
> the crack propagating.
> Googling informs me that the rock chip repair people are good at filling
> in holes, but there's a lot of hemming and hawing about whether they
> can keep a crack from propagating.
> I hate to blow $60 on a chip repair and have to replace the windshield
> next month anyway.
>
> Any chance that a vacuum pump and superglue will help? The kits you buy
> at the auto store show examples of fixes other than cracks.
> Doesn't have to be pretty, just not crack more.
>
> Direct personal experience?
> Thanks, mike

Well...
I went to the local glass shop. For $30 they drilled several holes thru
the front surface and filled it with UV cured stuff. He sez, don't
drill all the way thru the front half or it will delaminate. Used a low
speed battery powered Dremel and a carbide bit. Looked very easy to drill.
Took half an hour under pressure to fill the cracks. He also stuck a
pick in the hole and pried the crack apart to aid flow. Don't think I
would have had the guts to try that. Would never have been able to do
it with superglue...working time too short.

Result looks pretty good.
If the crack propagates within 18 months, they'll apply my $30 toward a
new windshield. And their new prices were the best in the area.
Sounded like a no-risk option...we'll see. Next time, I'll know what to do.
Thanks for the inputs.
mike

--
Return address is VALID but some sites block emails
with links. Delete this sig when replying.
..
Wanted, PCMCIA SCSI Card for HP m820 CDRW.
FS 500MHz Tek DSOscilloscope TDS540 Make Offer
Wanted, 12.1" LCD for Gateway Solo 5300. Samsung LT121SU-121
Bunch of stuff For Sale and Wanted at the link below.
MAKE THE OBVIOUS CHANGES TO THE LINK
ht<removethis>tp://www.geocities.com/SiliconValley/Monitor/4710/

On Mon, 07 Mar 2005 20:51:28 -0800, mike > wrote:

>Well...
>I went to the local glass shop. For $30 they drilled several holes thru
>the front surface and filled it with UV cured stuff. He sez, don't
>drill all the way thru the front half or it will delaminate. Used a low
>speed battery powered Dremel and a carbide bit. Looked very easy to drill.
>Took half an hour under pressure to fill the cracks. He also stuck a
>pick in the hole and pried the crack apart to aid flow. Don't think I
>would have had the guts to try that. Would never have been able to do
>it with superglue...working time too short.
>
>Result looks pretty good.
>If the crack propagates within 18 months, they'll apply my $30 toward a
>new windshield. And their new prices were the best in the area.
>Sounded like a no-risk option...we'll see. Next time, I'll know what to do.
>Thanks for the inputs.
>mike

Thanks for the update. I've made a note to not hit the center
flexible laminate. Other than that, sounds like we were close. Glad
it is fixed.

Lg

>Thanks for the update. I've made a note to not hit >the center
>flexible laminate. Other than that, sounds like we >were close. Glad

>it is fixed

And if you don't drill all the way through the cracked layer,
stopdrilling fixes nothing. There is still a cracked, non-radiused
medium that will crack further. The only reason the glass tech drill it
was to aid in polymer injection.

Dan

On 8 Mar 2005 07:44:48 -0800, wrote:

>>Thanks for the update. I've made a note to not hit >the center
>>flexible laminate. Other than that, sounds like we >were close. Glad
>
>>it is fixed
>
> And if you don't drill all the way through the cracked layer,
>stopdrilling fixes nothing. There is still a cracked, non-radiused
>medium that will crack further. The only reason the glass tech drill it
>was to aid in polymer injection.
>
> Dan

As a DIY'r, I would have drilled through the entire windshield at the
very ends of the cracks, and filled the holes with something purchased
for that particular application, delamination notwithstanding.

The worst that can happen is you buy a new windshield. NOT the end of
the world as we know it.

I can't speak for the "glass tech" or why he did or didn't do what he
did or didn't do. I don't much =care=. As I said, I've drilled glass
and glazed ceramics for YEARS and never had a problem. Then again, I
have the right tools, the experience, and the time to do it.

Lg

LG,

I've watched glass repair being done a few times in our neighborhood. These
guys do a very nice job for a small amount of money. I've been told that you
shouldn't postpone the repair too long because it is best to do the repair
before dirt and such get into the hole. Also, I was told that the pro doesn't
drill all the way through both panes of glass because that would make it harder
to inject the repair material into the hole and get it to spread out throughout
the opening. They count on the epoxy hitting the laminate and having nowhere
else to go except sideways into the cavity.

Next time, I'll have to observe and quiz them about the difficulty of drill to
exactly the correct depth. So far, I haven't noticed any sort of depth control
on the drill.

I like you advice about testing Usenet advice on junk cars. Everytime I learn
that a neighbor is considering having a car towed to the junkyard, I ask
permission for my son and I to experiment on the vehicle. For example,
it is a great opportunity to teach a kid about cosmetic body work.
Letting a teenager experiment on a junk car is a lot less painful than turning
him loose on a more valuable vehicle with rubbing compound, a power buffer,
Bondo, body paint, etc.

Gideon

==================

Lawrence Glickman wrote in message ...
On 8 Mar 2005 07:44:48 -0800, wrote:

>>Thanks for the update. I've made a note to not hit >the center
>>flexible laminate. Other than that, sounds like we >were close. Glad
>
>>it is fixed
>
> And if you don't drill all the way through the cracked layer,
>stopdrilling fixes nothing. There is still a cracked, non-radiused
>medium that will crack further. The only reason the glass tech drill it
>was to aid in polymer injection.
>
> Dan

As a DIY'r, I would have drilled through the entire windshield at the
very ends of the cracks, and filled the holes with something purchased
for that particular application, delamination notwithstanding.

The worst that can happen is you buy a new windshield. NOT the end of
the world as we know it.

I can't speak for the "glass tech" or why he did or didn't do what he
did or didn't do. I don't much =care=. As I said, I've drilled glass
and glazed ceramics for YEARS and never had a problem. Then again, I
have the right tools, the experience, and the time to do it.

Lg

On Fri, 11 Mar 2005 06:53:45 GMT, "Gideon" > wrote:

>LG,
>
>I've watched glass repair being done a few times in our neighborhood. These
>guys do a very nice job for a small amount of money. I've been told that you
>shouldn't postpone the repair too long because it is best to do the repair
>before dirt and such get into the hole. Also, I was told that the pro doesn't
>drill all the way through both panes of glass because that would make it harder
>to inject the repair material into the hole and get it to spread out throughout
>the opening. They count on the epoxy hitting the laminate and having nowhere
>else to go except sideways into the cavity.

I see your point there.

>Next time, I'll have to observe and quiz them about the difficulty of drill to
>exactly the correct depth. So far, I haven't noticed any sort of depth control
>on the drill.

Probably an "art" learned best by doing

>I like you advice about testing Usenet advice on junk cars. Everytime I learn
>that a neighbor is considering having a car towed to the junkyard, I ask
>permission for my son and I to experiment on the vehicle. For example,
>it is a great opportunity to teach a kid about cosmetic body work.
>Letting a teenager experiment on a junk car is a lot less painful than turning
>him loose on a more valuable vehicle with rubbing compound, a power buffer,
>Bondo, body paint, etc.
>
>Gideon

I love to take stuff apart. Problem is, when I'm working on my car, I
have to keep in mind it has to be put together again, so I can't let
myself get carried too far away.

But if I'm tossing something that has no salvage value, say an old
lawnmower or such, I'll enjoy taking all the bits apart to see how it
went together and worked for all those years.

Just a curiosity I haven't been able to shake, and the best thing
about it, is I can just throw the stuff into the garbage bin as it
comes out of the motor 8-)

So I get a chance to do an "Alien Autopsy" every now and then on
something before it goes to the landfill. If you have the TIME like I
do, it can be quite educational.

Lg

it will crack again and more.
old john

"mike" > wrote in message
...
> Got a nasty rock chip in my windshield. Three impact divots connected
> by a crack about 1.5" long. Short star pattern at each impact.
> It's well out of the normal field of view, but I'm very concerned about
> the crack propagating.
> Googling informs me that the rock chip repair people are good at filling
> in holes, but there's a lot of hemming and hawing about whether they
> can keep a crack from propagating.
> I hate to blow $60 on a chip repair and have to replace the windshield
> next month anyway.
>
> Any chance that a vacuum pump and superglue will help? The kits you buy
> at the auto store show examples of fixes other than cracks.
> Doesn't have to be pretty, just not crack more.
>
> Direct personal experience?
> Thanks, mike
> --
> --
> Return address is VALID but some sites block emails
> with links. Delete this sig when replying.
> .
> Wanted, PCMCIA SCSI Card for HP m820 CDRW.
> FS 500MHz Tek DSOscilloscope TDS540 Make Offer
> Wanted, 12.1" LCD for Gateway Solo 5300. Samsung LT121SU-121
> Bunch of stuff For Sale and Wanted at the link below.
> MAKE THE OBVIOUS CHANGES TO THE LINK
> ht<removethis>tp://www.geocities.com/SiliconValley/Monitor/4710/
>