Earthwormjim's Stuff

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PJ-27
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Re: Earthwormjim's Stuff

Post by PJ-27 » Thu Dec 06, 2012 5:44 pm

That's brilliant!

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earthwormjim
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Re: Earthwormjim's Stuff

Post by earthwormjim » Thu Dec 06, 2012 5:45 pm

PJ-27 wrote:That's brilliant!
LOL,thanks,I think it is going to shoot itself straight off the edge of the arena,9 times out of ten though!! :roll:
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Andrew_Hibberd
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Re: Earthwormjim's Stuff

Post by Andrew_Hibberd » Fri Dec 07, 2012 12:05 am

It needs a hovercraft style fin to direct the flow in one direction when upside down :D Looks like a lot of fun
TEAM GEEK!

PJ-27
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Re: Earthwormjim's Stuff

Post by PJ-27 » Sat Dec 08, 2012 4:37 pm

Where did you / what is the, Fan / Ducting you're using?

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earthwormjim
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Re: Earthwormjim's Stuff

Post by earthwormjim » Sat Dec 08, 2012 11:58 pm

I am using an 8 bladed 40mm edf unit.
Here is the Hobbyking EDF units with motors page...
http://www.hobbyking.com/hobbyking/stor ... Motor.html
Here is the Robot birds page...
http://robotbirds.com/catalog/index.php ... 6f013254d8
I am using this one... ADF40 -200 PLUS 2S 8600Kv
which is here...
http://robotbirds.com/catalog/product_i ... ts_id=6798

Hope that helps. :)
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peterwaller
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Re: Earthwormjim's Stuff

Post by peterwaller » Sun Dec 09, 2012 9:00 am

I have gone for a less powerful 6 blade 40mm unit with a brushed motor.
http://www.ebay.co.uk/itm/GWS-Electric- ... 53f124bafa
At 50 gms thrust it will need to make use of the suction effect if I can make it work but at least it is less power hungry at 1.5A.
It is on the back burner at the moment because of the semi automated work I am doing but will try and get back to it soon.

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earthwormjim
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Re: Earthwormjim's Stuff

Post by earthwormjim » Sun Dec 09, 2012 11:13 am

There are some interesting you tube videos,where someone has taken an eight blade fan,and removed 4 of the blades,re-balanced it,and come up with a much more efficient system,that doesnt eat batteries. Could be quite an interesting little project. :)

http://www.youtube.com/watch?v=8XYx1pcO4Mk

Cheers Jim

EDIT: I still reckon that a small efficient EDF coupled to a horizontal spinner,could result in a much more stable robot.That is where I see these units making the most difference.
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earthwormjim
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Re: Earthwormjim's Stuff

Post by earthwormjim » Sat Dec 22, 2012 11:51 am

I have recieved my micro Tachometer this morning. :D
It is a neat little bit of kit.
I fully charged The Barbarian!(Grrrr!) and measured the battery at 12.1V.
The Tacho shows the bar spinning at a maximum of 10230rpm,which is very good I reckon.
The motor is rated to 1000KV so should spin at 12100rpm,with no load.
I was expecting more of a performance drop!
It means that the tip of the bar is going at 120MPH,which is nice.
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PJ-27
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Re: Earthwormjim's Stuff

Post by PJ-27 » Sat Dec 22, 2012 5:40 pm

Awesome! I was very tempted by one of those but figured it would likely only render disappointing results...

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BeligerAnt
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Re: Earthwormjim's Stuff

Post by BeligerAnt » Sat Dec 22, 2012 6:23 pm

Thanks for posting the results Jim.
If you're getting 84% of the datasheet Kv value, then it seems your disc/blade is not providing too much load/wind resistance.
120mph should be "adequate"! ;)
Gary, Team BeligerAnt

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