the steel-tape requirement

[gh]

split off from the wHT thread

[Peter Michaelson]

OK, one of the livestream commentators just said that metal measuring tapes don't change dimension in the heat. Is that true? Also, how come no lasers for measuring hammer distance?

[gm]

OK, one of the livestream commentators just said that metal measuring tapes don't change dimension in the heat. Is that true? Also, how come no lasers for measuring hammer distance?

Steel tape is only for record measurements. The competition itself is measured by EDM equipment.

[gh]

Steel tape is only for record measurements. The competition itself is measured by EDM equipment.

and the steel tape requirement is one of the most ridiculous rules in the sport. What happens if a tape (of any kind) stretches? It gives SHORTER distances, not longer!

[gm]

and the steel tape requirement is one of the most ridiculous rules in the sport. What happens if a tape (of any kind) stretches? It gives SHORTER distances, not longer!

Which is why you use the steel for records, unless I am completely missing something.

[gh]

Which is why you use the steel for records, unless I am completely missing something.

steel expands in heat, no?

[gm]

steel expands in heat, no?

Fiberglass stretches.

[Powell]

steel expands in heat, no?

It does, but the effect is pretty insignificant within normal temperature range. For a throw of 76 meters, the difference between the temperatures of 0 and 40 degrees C is less than 9 cm.

[Alan Sigmon]

But that small expansion could make a difference. From the World Athletics World Record Progression book (100 yards):

9 3/5 Daniel Kelly (USA) Spokane 23.06.1906 Pacific Northwest AAU: 2. Robert Cary, 3. Rex Smith, 4. Forrest Smithson. In L.H. Gregory’s column in the Portland ‘Oregonian’ an account of Kelly’s performance appeared - “The afternoon was warm and during the meet the steel tape, which had been used to measure the course lay unrolled in the sun. After Kelly had won in that course, it was found to be 5 inches short of the required 100 yards... Then it was realized that the unrolled steel tape expanded under the heat of the sun and after it had cooled off another measurement showed the course to be slightly over the 100 yards. Proper affidavits were..forwarded to the AAU and the performance eventually became the world’s and American record”.

[Tuariki]

It does, but the effect is pretty insignificant within normal temperature range. For a throw of 76 meters, the difference between the temperatures of 0 and 40 degrees C is less than 9 cm.

9cm is a wole lot, especially if a record is broken by 8cm

[Powell]

9cm is a wole lot, especially if a record is broken by 8cm

But I'm talking 0 to 40 C, which is a pretty extreme range.

[Conor Dary]

and the steel tape requirement is one of the most ridiculous rules in the sport. What happens if a tape (of any kind) stretches? It gives SHORTER distances, not longer!

I presume they use some sort of scale that measures the pull on the tape....

[Conor Dary]

But I'm talking 0 to 40 C, which is a pretty extreme range.

Like 32 to 122....

Still 9cm is quite a bit that is almost 4 inches...Hayward has had meets in the 30s and over 110...

[lonewolf]

Measuring 200-300 throws to a centimeter by either steel or fiberglass tape is laughable. Orientation of the tape and irregularity of the ground is more crucial than heat expansion of the tape.
Even with EDM, you are measuring an approximate distance with great precision due to inconsistent marking.

[gh]

But the bottom line is that WA rules are saying it's not a legal WR measure unless it's steel, and a non-steel tape, if anything, is going to stretch, not contract, yielding a shorter measure. It's akin to not ratifying a throws mark because the implement came in too heavy!