Hot PIC: Kenton shoots ice ball with slingshot at roofing material for hail course.

[Nick Gromicko]

http://www.nachi.org/roofdamageassessmentcourse.htm

[Carl A. Brown]

Why

1. Does the step flashing not go up the wall high enough?
2. Is there no kickout diverter.
3. Why is he on the pick with no saftey equipment on?

[Larry D. Kage]

Originally Posted by cbrown1

Why

1. Does the step flashing not go up the wall high enough?
2. Is there no kickout diverter.
3. Why is he on the pick with no saftey equipment on?

And why don't every other shingle gusset line up on the left of the sky light?


It'll be fun to see what's put together.

[Carl A. Brown]

Picky picky picky.

The safety is a big issue even if I spelled it wrong the first time.

[Ed Fako]

Although a sling shot can provide the damage to the shingles, I believe a more reliable method of firing the projectile should be used.

The sling shot force is too objective. You would need an apparatus that can fire at recordable and expected velocity and force, with recorded masses of the spheres.

Would a Paint Gun launcher achieve this more accurately?

Haag Engineering has a projectile launcher shown in their documents.

Another "Fact" is that many/most insurance companies allow a hail damage claim to only be filed from One Year after the Reported Hail incident, unless the area is declared a Catastrophic Damage Event.

Spot Shingle Granule Loss does not necessarily become visually evident immediately after impact. Just a slight loosening of the granule adhesion has occurred, but due to that loosening, the subsequent wind, rain and snow scouring and will reveal more significant granule loss and exposure of the asphaltic sub-surface materials, creating a condition set for premature degradation from the UV rays of the sun.

Haag is in the pocket of the insurance industry and their conclusions are suspect. They proclaim that granule loss is Not Shingle Damage, whereas the shingle manufacturers insist that it is.

I have written in great depth on this topic and have substantial experience with the forensic matters, from a non-laboratory in field perspective.

Ed

[William J. Decker]

Originally Posted by Ed Fako

Although a sling shot can provide the damage to the shingles, I believe a more reliable method of firing the projectile should be used.

The sling shot force is too objective. You would need an apparatus that can fire at recordable and expected velocity and force, with recorded masses of the spheres.Ed

I believe that you meant to say "subjective", as in non-reproducable.

In any case, I don't think that actual hail velocity and mass is static. It would vary according to many factors (size of hail stones, falling height, wind direction and velocity, etc).

I would posit that this example is good enough for government work.

In any case, this was fun!

Hope this helps;

[Kenton H. Shepard, CMI]

Will Wins! It was for fun.

This was for the opening shot of the Hail Damage Recognition course video, taken with a high-speed camera so that we can show the ice ball exploding on the roof in super slow motion.

In 30 years of work in the building trades, If I had to rank this stunt from 1 to 10 as far as danger goes, this would be a 2, if that. I've spent a lot of time working up high.

If you don't know how to drive a car, it's dangerous to get behind the wheel of a powerful car. If you're a good driver, it's not very dangerous to get behind the wheel of a regular car on a safe road.

[Nick Gromicko]

Kenton.

Go outside and pull back the slingshot a certain distance and launch an ice ball up into the air. Count the number of seconds it takes to land. Vertical motion is independent of horizontal motion so you don't have to launch straight up and run (you can launch at an angle).

Now, if you give me the flight time, I'll tell you the speed at which your slingshot launches ice balls!

At its highest point the ice ball won't will be at zero vertical speed (not going up or down) so it will be equivalent of dropping the ice ball from that height. The speed at which it hits the ground will be equal to the speed at which it launched from your slingshot.

For fun, let's say it remained in flight for 8 seconds. Your ice ball took 4 second to go up and 4 seconds to return, so I don't need to know how high it went up. 4 seconds after you launched, the ice ball was not moving vertically. Now ice balls (and cannon balls for that matter) fall at 9.8 meters/second. The rate at which anything falls is independent of it's mass, so I don't need to know the weight of the ice ball.

So...

-- 1 second later it was falling at 9.8 meters/second.
-- 2 seconds later it was falling at 19.6 meters per second (speeding up!)
-- 3 seconds later it was falling at 29.4 meters per second (going even faster!)
-- 4 seconds later (when it hit the ground) it was falling 39.2 meters per second.

This means that it launched out of your slingshot at 39.2 meters per second.

There are about 1600 meters in a mile and 3600 seconds in an hour...so...

1 meter = 1/1600 miles.
1 second = 1/3600 hours.

so dividing we find that...

1 meter per second = 2.25 miles per hour.

so...

39.2 meters per second = 39.2 times 2.25 = 88 miles per hour.

I have to make a slight correction for wind resistance but in this example, your slingshot would launch similarly sized ice balls at 88 mile per hour (in any direction).

[Darren Spencer]

Nick, That's exactly what I came up with !

[Kenton H. Shepard, CMI]

Latht time I twy catching that itheball in my teeth. Thoh much for my video inthpecthion hothting caweew!

[John McKenna]

Originally Posted by kshepard

Latht time I twy catching that itheball in my teeth. Thoh much for my video inthpecthion hothting caweew!

Funny...

[Brian E. Kelly]

Originally Posted by kshepard

Latht time I twy catching that itheball in my teeth. Thoh much for my video inthpecthion hothting caweew!

OMG that is funny Kenton.