- #1
PJ Adams
- 1
- 0
Hi all,
Firstly - I'm not a collage student but this seemed a good place to ask the question! Any help welcome
As a fun home project, I've been building a motorcycle dyno, connected to a PC via a custom made PIC based device. Have most of it worked out with regards to data collection, ignition reading from the bike, etc.
Was planning to make a dyno drum from one solid piece of steel, thus making the physics easy with regards to moment of Intertia (simple solid cylinder) - but steel is (now) very expensive, so I wanted to make a steel hollow drum, but filled with 'something' to give it weight for the motorcycle to work against. I was thinking possibly concrete because it's cheap & heavy - with the drum sealed as a solid unit once the concrete was solid.
I would know the exact dimensions & weight of the steel used to create this hollow drum - but how would I use the dimensions of the concrete in the physics?
Would I have to weigh the drum before filling? Then fill it & allow the concrete to set & weigh again? Then seal the end of the drum and weld it shut & wiegh again for a final total?
That would give me weights before and after - but what does concrete weigh per cm3? Arggh! (they told me I would actually use physics once I left school & I didn't believe them! )
Umm...advice welcome!
Paul
Firstly - I'm not a collage student but this seemed a good place to ask the question! Any help welcome
As a fun home project, I've been building a motorcycle dyno, connected to a PC via a custom made PIC based device. Have most of it worked out with regards to data collection, ignition reading from the bike, etc.
Was planning to make a dyno drum from one solid piece of steel, thus making the physics easy with regards to moment of Intertia (simple solid cylinder) - but steel is (now) very expensive, so I wanted to make a steel hollow drum, but filled with 'something' to give it weight for the motorcycle to work against. I was thinking possibly concrete because it's cheap & heavy - with the drum sealed as a solid unit once the concrete was solid.
I would know the exact dimensions & weight of the steel used to create this hollow drum - but how would I use the dimensions of the concrete in the physics?
Would I have to weigh the drum before filling? Then fill it & allow the concrete to set & weigh again? Then seal the end of the drum and weld it shut & wiegh again for a final total?
That would give me weights before and after - but what does concrete weigh per cm3? Arggh! (they told me I would actually use physics once I left school & I didn't believe them! )
Umm...advice welcome!
Paul