Ian, since you are getting the disc CNC milled, you should be able to machine slots in the disc for the teeth to slide into. If the disc and teeth are appropriately keyed, the bolts should not take any significant load from an impact.
Sorry that should be I= Polar moment of inertia of masses. For a rectangular plate
I=M(a^2+b^2)/12
M=mass
a=width
b=length.
To increase the I value you want to make the propeller broder at the tips.
Also you want to make it of pretty thick material to stop it bending. Mines 12mm thick steel and Matilda still cut through it and bent it slightly up where she hit it.
Richard Wenman
Team Mayhem
richard, what grade of steel do you use for your disk?
I just used standard mild steel since I figured that this would be strong enough in 12mm thick.
Oh boy was I wrong.
What sort of speed are you looking at for this propellor Daniel?
Richard Wenman
Team Mayhem
We use Mild steel aswell. Matilda managed to bend our disc slightly aswell, its 33mm thick at the rim!
Not to mention the contact with Mechaniac that had some effect on the teeth.
Gary
Consider an IC motor like ours for Executioner.
The advantage of our IC is that it weighs 3kg and yet still spins the disk to over 8000 in 2 seconds from dead stop. Another advantage is we dont have to carry any extra weight for batterys to power an electirc spun disk! This leaves us more weight for ARMOUR.. A good quality chainsaw motor will never cut out and will start everytime first time. It will also quite happily run in any orientation even upside down too.
The downside is price :sad: I paid 300 I think for the Stihl! So not cheap I know.
We have learnt our lessons from series 7 and now sport a new very tuff scoop at the front and also an aluminum hub for the disk itself with bolt on blades. This has enabled us to increase the reach slightly of the disk and also lessen the weight overall. Along with the new speed controler from here (Anyone want a secondhand vantec?)
http://www.roboteq.com/index.shtmlhttp://www.roboteq.com/index.shtml
We HOPE to at least once manage to get past the first bloody round :sad:
If you know what youre doing, you can get some chainsaws to peak at over 20 horsepower! There are already some teams who have done that with a chainsaw from the Swedish Husqvarna.
I see Whyatchi superheavy i think uses 2 15hp ic engines.
im planning on using a small chainsaw in my featherweights spinning weapon.
did you have to modify the clutch to take a pulley/sprocket and if so how did you do it?
anymore info you can divulge on petrol engines?
thanks, glen
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