Air in tires adding to weight?
 

Our robot is on the edge of the weight limit [119-121lbs].
We do have pneumatic tires, 6 of them 10inches, would taking the air out of them help make a difference in weight? Also would that be legal?

Re: Air in tires adding to weight?
 

If you deflate your tires to make weight, you must compete with deflated tires.

Re: Air in tires adding to weight?
 

I doubt it will make any difference. Air is fairly light (hence the term light as air). Also if you do this and then re-inflate your wheels and that gets you over weight you are illegal, you may have passed inspection with your under inflated wheels but its still breaking the rules even if you don't get caught. You are better off speed holing your bot in many places

Re: Air in tires adding to weight?
 

Air is a low density form of matter. Unless you compressed the air to an extreme level I would find a solid piece of matter a lot better to take off for weight reduction.

Re: Air in tires adding to weight?
 

Thanks of the replies, I guess I will get that hole drill warmed up...

Re: Air in tires adding to weight?
 

1 word . . . helium. :D

Re: Air in tires adding to weight?
 

Why would you say this? Teams are encouraged to let all the air out of their pneumatic tanks when weighing, but can compete with them fully charged.

Is there a rule you can reference that verifies this claim?

Re: Air in tires adding to weight?
 

FYI, at 35psi and room temperature, air weighs about 1/4 lbs per cubic foot (source).

So... ...yeah you better plan to save weight someplace else.

Joe J.

Re: Air in tires adding to weight?
 

This is why I think letting the air out of the tires is legal.
1/4 LBS for 1 sq foot.
6 Tires that are 10x3inches
Hm that might help.

Re: Air in tires adding to weight?
 

Pneumatic tires are not pneumatics. (Blue box, [R71]).

The reason pneumatics are supposed to be empty when weighing (and all through inspection other than the power-on check) is for safety, so that something doesn't go totally haywire. Pneumatic tires don't have that problem.

Therefore, I can conclude that pneumatic tires, if deflated for inspection, must compete as inspected; i.e., deflated.

Oh, and Dr. Joe is right about air's lack of weight savings. Just trust me on this (other than: I was dealing with about 3 IWC air last summer).

Re: Air in tires adding to weight?
 

Is helium a legal robot building substance?

Re: Air in tires adding to weight?
 

I didn't see it as being illegal. However, keeping it from escaping is not easy. And to get much lift... well, let's just say that you'd probably either have a structural failure or negate all of the lifting capability by adding strength to have any chance.

Re: Air in tires adding to weight?
 

There are plently of ways to lose weight.
I whould try cutting holes or trinagles in your bot if possibale.
If we can see a pic of if we might be able to give some ideas.

Re: Air in tires adding to weight?
 

I figured this thread had to be trolling...but then it was serious???

Re: Air in tires adding to weight?
 

So ~0.13 lb total*, or about half the weight of the digital sidecar, [EDIT] or about the same weight as all of the data in the internet in 2007 [/EDIT].

*Assuming the wheel's inner tube is a torus of R=3.5, r=1.5 in. Volume is V=2(pi^2)(R)(r^2).