here we have a crack coming down from
the top of the windshield with the
impact about two inches from the molding
it comes down and curves goes over by
the rearview mirror this crack is about
17 inches long it's definitely a job for
the multi head injector the first step
is to put a stop drill at the end of the
crack the goal is to drill about halfway
down to the plastic what you do is you
drill a little bit and you make a light
tap if you drill too deep you're not
going to get the correct bullseye
if you drill too shallow and you tap too
hard you can cause the crack to go past
your drill hole so with practice you'll
get good at this but I'm going to drill
partway down and I'm going to give it a
little tap you can drill on low or you
can drill on high if you have a new bit
the bit drills faster but with a little
practice you'll get a good feel for this
drilling and tapping and stop at the end
of the crack once you've drilled and you
think you got the proper depth we're
going to give a little tap with your
bullseye tapper and see we didn't get a
bull's-eye which means we're too shallow
so we're going to drill just a little
bit more it doesn't take much just a
little bit more and sometimes you'll get
the bullseye you wanted now we're going
to give another light little tap and we
still didn't get the bullseye we wanted
so we're going to drill a little bit
more the goal is to drill a little bit
at a time and not get too deep because
then you won't get the bullseye
there we go we got our bull's eye that's
exactly what we're looking for now we're
going to load the Malta head injector
the Malta head injector needs to be
loaded from the bottom remove the o-ring
and then we're going to add six to eight
drops of resin depending on how long a
crack you're going to repair but usually
six or eight drops is adequate for most
cracks up to about 24 inches then you
want to back the piston off if you need
to add a little more I put about four
drops in the first time realize I didn't
have the piston backed off far enough
okay now we've got our eight drops
approximately now we'll reinsert the
o-ring there isn't a right or wrong way
to put the o-ring in they'll go in
either way you kind of put it at an
angle and then pop it in you'll get good
at this with practice easy there's the
concern now we're going to load the
second barrel on the Malta head injector
the same way as we loaded the first
barrel back your piston off Oh though
you were messing with learning at about
eight drops of resin Q instead of
cutting in the film with an insert at
reinstall your o-ring again insert it
and cut cut the rest of it
that's it okay and then we'll do this
shot of me now we're going to add the
suction cup lubricant you need to have a
good amount of lubricant when you're
doing these long cracks because you
don't want your tool to stick partway
down the crack if the tool sticks it
will cause you to air up the crack that
you've already injected yeah so we're
going to mount the tool you want to have
the injector and adjusting bolt backed
off you slide up the crack keeping your
injector right over the crack put it on
about a half-inch past your bull's eye
stop turn both the injector and the
adjusting bolt down until it touches the
glass and then go about another turn
Claire and everything we're going to put
our extension arm on because we're
having a little hard time reaching this
crack since it's clear up in the middle
this is a patented extension arm that
we've added to this tool
now you turn up the pressure on your
first barrel
Oh lifting pressure on the resume
then we're tend to pressure up on the
second barrel now the crack is tight on
the tip so we're going to have to flex
the crack a little bit to open it up you
can either use a crack expander I use my
son thumb sometimes I use just like a
little wooden dowel just something to
get it flexed open just enough that the
resin will start dinner and we see the
resin starting to go in you can see I go
down to the crack not back up a little
bit so I can see the resin going in it's
just the first two or three inches that
are going to be tight if that depends a
lot on the crack the trick is to be able
to flex the crack open just enough that
the resin goes in but not flex it too
hard and cause the crack to spread past
her stop point if this does happen you
push too hard to spread you just have to
go out and put another stop on the crack
you will want to keep the crack out of
the Sun until you get good at it now a
lot of times I'll repair right out in
the Sun because I'm pretty confident and
what I'm doing and I wanted you to be
able to see on the video if I started to
shade this repair you wouldn't be able
to tell what's going on but but if
you're good enough yeah you can repair
right off the Sun we're just going to
finish following the crack right up to
the edge make sure you're getting all
the resin and both barrels going in
there it's going to start leaking out
because the crack is gapi at the edge we
run all the way up to the edge and then
I'm coming back to the impact point to
leave the resin under pressure on it a
little bit to make sure it feels good
then you want to cure this crack in
about ten or fifteen minutes in the Sun
you want to make sure the crack is good
and cured before you pull your tool off
because you might flex crack shutting
doors can flex the crack people didn't
out of the vehicle or moving around the
vehicle can also flex the crack so you
want to make sure that the crack is not
disturbed while you're injecting it and
while you're waiting for it to cure
under pressure if you want to you can
use cure tabs and pin filler and that
will help air getting in the crack if it
does get flexed you just lay down the
pit filler and lay down tap next to tab
next to tab and that's a good precaution
when you're new
then we're going to clean up the extra
grease along the crack I use a razor
blade just to make it easier then pull
the tabs off now this is after we've let
it cure for 15 minutes room
and then just scrape straight down the
crack with your razor blade
just keep working your way down the
crack all the way to the edge
if you don't have sunlight you can use a
cure lamp to cure and in the evening on
cloudy days that's a really good idea
when it comes to cracks you want to make
sure they're good and cure before you
let the vehicle drive away
now we'll take some glass cleaner we're
going to fill the pit first
sometimes the impact is fairly large
where the rock started to crack so we're
just going to fill that in with bit
filler and a tab and let that cure
now pit filler were cure in about 15
seconds to 30 seconds it doesn't take
long
then you can pull the tab then you want
to scrape straight on if you scrape at
an angle then you'll gouge out what you
already did clean it up with some glass
cleaner inside and out
we have less than a quarter of one
percent failure rate on these cracks now
I'm going to trace with our scribe down
the crack so you can see where it was
now this crack was about six months old
so it has a little dirt in it once I get
to this part you'll see the dirt that
lasts six inches has some dirt so it
shows up a little couldn't really see
most of it I can't
you