zeroing in on a star leg in the middle of W/S

[scratchy]

These rock chips have a way of hitting dead center on big pickups and SUVs. Leaning over to drill the end of a crack or star leg gives a false view of where to drill because of viewing at an angle. Sometimes I get it just a little off to one side after drilling. This has been a big pain sometimes. How are you guys centering in, using a ink marker or something????

[cure4glass]

Are you attaching a mirror to the inside of the W/S?
When I'm in doubt I will mark the suspected end with a fine tipped marker , then get inside the vehicle and inspect it closer to make sure I'm about to drill the right spot.I always pop a mini bullseye when I drill and this adds a little more forgiveness if I do happen to get a smidge to one side or the other.I usually leave a 1/16" or so gap between the end of the crack(or leg) and the drill spot to allow the crack or leg to run into the bullseye, otherwise there's a chance of running past the drillhole.

[Steve]

I sometimes get a little nervous about popping that bullseye at the end of a crack because sometimes the crack will run past the bullseye. I drill about half way down or more and pop it gently, sometimes it works fine sometimes not. Anybody have any good advice or is that just the way it goes.

[cure4glass]

Steve,
Try backing off from the end a little, about a 1/8" or so before popping the bullseye. I use a sewing needle.The best advice is probably to practice on a scrap wondshield until you get comfortable.

[jonnyques]

I had this happen today. I drilled to stop a leg that was growing. I drilled 1/4" away from the end of the leg. I must have taped to hard to make the bullseye as the crack shot through the bullseye and out the other side. It just seemed the flex created from the strike flexed the glass before the bullseye was formed.

[screenman]

All the replies so far have been very good. The only thing I would like to add though if you mark then screen inside the vehicle and then look at it from outside at any angle the mark will seem to have moved this is due to the thickness of the glass. Try this to see how this works, get inside the car looking directly at the break not from one side or the other place your probe on one of the legs and keep it there, then move your head and you will see that it appears the probe has moved. Keep practising you will get there.