FSAE rules 2011: Material requirements error?

[Ricki]

In the new FSAE 2011 ruleset (http://students.sae.org/competitions/formulaseries/rules/2011fsaerules.pdf) point B3.3.1 states that the following tubing dimensions are allowed:

Side impact structure,......: Round 1.0 inch (25.4mm) x 0.065 inch (1.65mm)
Round 25.0mm x 1.75mm metric
Round 25.4mm x 1.60mm metric
Square..........

This made me wonder why the 1 inch tubing is mentioned twice, with different wall thickness. To me this looks more like a typo and the third tubing options should instead have been: 26.0mm x 1.60mm, which would have been more in line with the tubes specified under "Front bulkhead...".

I was woondering if this was a known error, and if anyone know about a potentiel correction, or one should just take it as a small(Very small) bonus for people using the metric system?

[Kirby]

Originally posted by Ricki:
In the new FSAE 2011 ruleset (http://students.sae.org/competitions/formulaseries/rules/2011fsaerules.pdf) point B3.3.1 states that the following tubing dimensions are allowed:

Side impact structure,......: Round 1.0 inch (25.4mm) x 0.065 inch (1.65mm)
Round 25.0mm x 1.75mm metric
Round 25.4mm x 1.60mm metric
Square..........

This made me wonder why the 1 inch tubing is mentioned twice, with different wall thickness. To me this looks more like a typo and the third tubing options should instead have been: 26.0mm x 1.60mm, which would have been more in line with the tubes specified under "Front bulkhead...".

I was woondering if this was a known error, and if anyone know about a potentiel correction, or one should just take it as a small(Very small) bonus for people using the metric system?

Has been and always been this way.

I think it is designed to remove any obfuscation from people that get stuck (like Australia or Canada) that get weird tube sizes. For example, our tube was sold as metric, but is 25.4mm x 1.60mm due to some company, somewhere, using strange dies.

I just wish they would allow 25.4" x 1.2mm Metric for front support structure, which is the most common CDS we can get. They allow 1" x 0.0049" (1.24mm) or 1" x 1.25mm Metric.

[BeunMan]

Don't know a lot about this, but looks like an imperial to metric conversion with multiple options. Probably just standard tubing sizes.

[Sormaz]

Hah, since when do you get to choose?

Do they do the same thing with currency exchange? I think I just figured out how I'm going to make it.

[Michael Royce]

Ricki,
ElectroMan is correct. It is basically "inch" or "imperial" tubing versus "metric" tubing. The SAE has this convention of dual dimensioning things that are not metric! So if you are in the USA and buy "inch tubing" you get buy the 1.00 inch x 0.065inch wall tube. If you are in Europe and other places where things are metric you get the 25.0 mm x 1.75mm tube. However, apparently, there are some "metric" countries where you can buy 25.4 mm x 1.60 mm tubing. Therefore, the Rules Committee listed it as an option and hence the confusion.

[PeterK]

I blame Jimmy Carter.