Prodigy evolution

[ady]

Work has already started on an additional fw, just wondered if 4mm ali grade NS4 5251, is ok for a chassis.

It seems like quite a soft grade (60 on brinell hardness) and the tensile strength (200ish) isnt great. Most peopel tend to use HE30 (6082T6) which is better than 5251. We are currently using Alumec 89 which has a tensile strength of 575 N/mm sq and a hardness of 168. But you cant weld Alumec 89, which is a down side, really depends on what you have planned.

[ady]

cheers ed, its only to build something basic for my daughter for whiteboards, we are moving more into feathers, and concentrating on these for a while,we have also started on a fw spinner, 3kg spinning disc, with huge teeth which are interchangable, will be completed by december. prodigy is also having completly new drive, so got a very busy few months ahead.

Dont forget that KE=mv2 so increasing the speed of the disk has much more effect on the energy than by increasing the mass. And the heavier the disk the longer it will take to reach top speed.

But 3Kg will be the heaviest disk about, fun.

[RogueTwoRobots]

I reckon my drum will be about 3kg too once its built, and itll hopefully be done by December also, so we may well come disc to drum Adrian, could very well be fun

[typhoon_driver]

Ed thats only true of an object in a straight line.

When you start rotating things get a bit trickier. The equation is basically the same but your kinetic energy is dependant on how the mass is distributed. To cut a long story short put as much weight to the outside as possible.

A useful little tool for getting a rough figure on the KE of a disc can be found here,

http://www.teamcosmos.com/ke/ke.shtmlhttp://www.teamcosmos.com/ke/ke.shtml

Its all in those silly imperial measurements that the Americans seem ever so fond of but with a small conversion program its easy enough to use.

[grant_ploughbot]

And dont forget, its better to get more energy in your disc at around 2000rpm that at 8000rpm. Too fast and you wont get good enough engagement on your opponent.