spinner bar ratio

[Danjr1]

what ratio/rpm at the weapon tip would i need if i ran a right-angled X-bar, about 40cm across, from a car fan motor? would (in theory) be running at 24v?

thanks, dan

update: using that team cosmos calculator, I've worked out roughly that id need the cross-bar to spin @ around 2500rpm to make 7.6K joules. that a decent number? and possible on a car fan motor? if not, i guess ill be going for a speed 900

[typhoon_driver]

Re: spinner bar ratio

not sure what you mean by a right angled x bar but a car fan motor you can pretty much go for a 1:1 ratio although running it at 24v might be a little much. 12v will provide more than enough power.

[Danjr1]

Re: spinner bar ratio

like this +. that shape, 40cm tip to tip. 1.5cm thick. should be around 5kg (I've taken the hardox density of around 7.86g per cu. cm).

hmmmm, may have to be a speed 900 then. the motors would be 24v and id only want to use one battery. on that motor, ratio around 2.5:1?

[typhoon_driver]

Re: spinner bar ratio

what motors are 24v? Your drive? What battery are you talking about?

[Danjr1]

Re: spinner bar ratio

the drive motors would be 24v so id be running one 24v battery

[typhoon_driver]

Re: spinner bar ratio

what motors are they?

[Danjr1]

Re: spinner bar ratio

drive motors are 18v drill motors being run at 24v, weapon motor would be a speed 900. this is all theoretical at the moment! I'm sketching up the weapon and pulleys for kenny. plan would be to have v belts running on the pulleys.

[typhoon_driver]

Re: spinner bar ratio

then buy some replacement 12v drive motors or run the 18v ones on 12v and use a car fan motor. You will need two speed 900s to run a weapon that big without burning out the motor. You would probably be better running it off a car fan motor for sheer oomph out of the blocks.

cheap replacement motors,

http://www.ebay.co.uk/itm/Johnson-600-s ... 3f0bb5b5f4

[Danjr1]

Re: spinner bar ratio

still got the old argos motors! could run at 16.8v on two electronizes and run the car fan motor on that? and on a 1:1 ratio, it would roughly get up to 2500rpm?

thanks again for the help!

[dragonmaster_1]

Re: spinner bar ratio

Dragonstrike uses a car fan motor of a Mondeo at 1 to1 ratio on 24v
http://www.youtube.com/watch?v=lV9oBPDI1so

[typhoon_driver]

Re: spinner bar ratio

should be fine at that

[Danjr1]

Re: spinner bar ratio

nice, and I'm guessing the car fan works fine at 24v? is 7.4K joules a nice value for a spinner? am i right in thinking hypnodisc was around 4K joules?

issue I'm working at now is how to join a pulley to the bar in a way that it won't snap!

[dragonmaster_1]

Re: spinner bar ratio

Yes they work fine on 24v not burnt one out yet

[dragonmaster_1]

Re: spinner bar ratio

The Mondeo fan motors are made by Bosch. At 12v Nominal speed is 3450rpm no load.
Got mine from the local breakers yard £5 each.

[Danjr1]

Re: spinner bar ratio

sweet. i pass a car dump on the way to work everyday so sourcing won't be a problem.

looking at these types of pulleys, http://www.technobotsonline.com/pulleys ... x16mm.html

how would you join one of these to a spinner?