Featherweight Database

[anukhet]

Featherweight Database

.......and friends have to be pretty close to stop the i rolling onto the floor

....strange AND macabre :wink:

[Kenny]

Featherweight Database

quote: Alan young

but can he lift a heavyweight?

you have seen today at newcastle that it did and we just nearly flipped behomoth

[blazerbotics]

Featherweight Database

but you needed G3s help :P

[Kenny]

Featherweight Database

nah you will see if you recorded it i could lift it up

btw i had the lift it up and keep it up for g3 to get under then i let it go so g3 got squashed

thanks
kenny

[robjones]

Featherweight Database

Ive updated my profile with a completed all-new microCHIP. The blades are 1.2Kg in total but spin at 6000rpm. The v belt has still to be fitted.
Rob

[Mouldy]

Featherweight Database

Hi Rob,

How come you have a 1:1 reduction with huge belt pullys....why not make smaller ones and loose alot of weight? would be the same gear ratio just smaller and lighter.

[typhoon_driver]

Featherweight Database

but it wouldnt look as cool

[blazerbotics]

Featherweight Database

also more likely to slip if smaller.

[stu]

Featherweight Database

also more weight on the disc side means more Knetic Energy.

Mr Stu

[Mouldy]

Featherweight Database

Spose it does look better with big pullys

[fwsorg]

Featherweight Database

Big pulleys stand up to more punishment from Eds whirly bit as he put it.

[robjones]

Featherweight Database

Ive messed about with diddy pulley on feathers (eg BlacknBlue)and watched other feathers for ages and I decided to go for BIG ONES!! They only weigh 400g each and take a beefy 13mm v belt. It never comes off or slips due to the huge surface area of contact. With the blades needing to be bolted on I needed something substantial in order to take the punishment (An EV Warrior @ 36v). Its worth remembering that the pulley itself adds to the MoI (Possibly both pulleys do?)
The mounting is aluminium and the inner shaft is 20mm titanium. Sadly it all weighs 12.7 Kg so I may have to run it with just one 500g blade not two, unless I can make savings elswere.

[stu]

Featherweight Database

How about using 8v batteries.
Im sure others would agree!

Mr Stu

[geoff]

Featherweight Database

Rob, That is one nice looking bit of kit.
Having played with many types of belt / pully arangements for weapons drive, the one thing we have learned is that it is always handy to have a little slipage in your drive train. Think on this.. You manage to bring that EV to a dead stall @ 36V any idea what the stall current is? ...Trust me, its a SERIOUS number of amps!!
Its more than possable to weld relay contacts shut (with all the embarassement that causes when you discover that you cant turn your weapon off!!)
Not to mention the excess loading on your battries, increasing the very real chance of some high quality pyrotecnics!:sad:
Yes, you will gain a little MoI from the bigger pullies, but it is only a little. For what its worth I would set that up with just enough slack in the belt that if you were to lock the blades, the EV is JUST capable of slipping the belt.
A far as reducing the 0.7Kg are you using Ni-CAD or Ni-MH batts.? Remember 36V of Ni-Cad weighs around 2.8 - 3Kg but 36V of Ni-MH will come out somewhere around 2.1Kg.
Oh yes, just one other thing..Just how thick are those polycarb body panels? :wink:

Regards,
Geoff.

[stu]

Featherweight Database

Thicker than your polycarb pannels, so go back to your Astro flight!

Mr Stu