Windshield Repair Forum

We all know that popping a mini-bull at the end of a long crack relieves the stress on the crack.

For the purpose of this discussion, lets assume that we are only stopping a crack (not filling it).

Has anyone ever tested or experimented to see just how strong a mini-bull is? Not with a specific measurement of course, but have you ever wondered just how strong it really is?

I was curious if anyone has ever compared a standard long crack (no mini-bull) and a standard long crack (with a mini-bull)?

How much more stress (or pressure) can a relieved crack take before it cracks out beyond the mini-bull?

There is probably not an easy way to actually measure it, but what would you agree with...

A long crack relieved by a mini-bull is...

1. A little stronger
2. Somewhat stronger
3. A lot stronger
4. Extremely stronger.

I pop mini-bulls all the time, but I have never actually tried to get a crack to run through and beyond a mini-bull in practice.

Any thoughts on the strength of a mini-bull by itself?

I would say that its : No.3 a lot stronger, compared to a crack without a mini bullseye.

I would say that if the mini bullseye is done right, it would be a lot stronger. But it is still broken glass.

Are there any wsr techs out there who do not pop a bullseye at the end of a crack?
If so ; what kind of results do you get?

A filled minibull's eye significantly reduces the risk of a run. A crack will either go around the minibull's eye or go right through it, if it is a stress crack where the glass is spreading on the laminate.
Some repair guys drill a decent sized hole at the end of the crack instead of popping a minibull's eye. I stick with the mini bull's eye as it looks better and has earned my trust as an effective stop.
NOT putting a stop to a crack is very risky.

Does the size of the bullseye matter?