Brushless Losi 8ight 1/8th Buggy Conversion (Videos)
 

Hey, guys. So I've recently started an 8ight conversion project.

Chassis: Losi 8ight
Motor: Feigao 540C 8XL
ESC: Mamba Max
ESC Mods: 1x 25mm Novak Fan & 1x 2700Uf 25V Capacitor
Battery: 5000MAh 4S Zippy-H
UBEC: CCBEC
Gearing: 18/46, 18/48, 16/46, 16/48

http://rc.jeffjassky.com/galleries/b..._6991 copy.jpg

More photos to come.

-Jeff

http://rc.jeffjassky.com/galleries/b...t/IMG_7020.jpg

http://rc.jeffjassky.com/galleries/b...t/IMG_7021.jpg

http://rc.jeffjassky.com/galleries/b...t/IMG_7022.jpg

http://rc.jeffjassky.com/galleries/b...t/IMG_7027.jpg

http://rc.jeffjassky.com/galleries/b...t/IMG_7029.jpg

http://rc.jeffjassky.com/galleries/b...t/IMG_7030.jpg

http://rc.jeffjassky.com/galleries/b...t/IMG_7033.jpg

http://rc.jeffjassky.com/galleries/b...t/IMG_7035.jpg

The battery tray itself was made from white-finished aluminum. I then covered it with black adhesive vinyl. the white didn't look good :) The vinyl was scrap from a sign-making shop. I was charged only $3 for about 4 square feet worth which is plenty to easily cover 5-6 boxes... The padding inside is "Darice" brand "Foamies Sheets" sold at walmart for $0.47 per 9x12" sheet. It does not have an adhesive back but when matched with 3M Carpet Tape (very thin) it adheres quite well! The lower layer of foam is running lengthwise with holes cut for the button heads to sit in (as pictured above) while the top layer runs width wise and up the side walls to better cover the heads of the screws and protect the battery which is also pictured.

Here are the mounts we made for the box. Pretty simple. They raise the box just enough to clear the radius of the chassis edge and the side guard dirt deflector thing.

http://rc.jeffjassky.com/galleries/b...t/IMG_7037.jpg

I ran it for a few minutes outside.. and decided to take some more shots. I kept my street-basher tires on. You can tell about half of the lugs are missing. Pretty crappy tires.. but I guess you can't complain for $20/set of 4 shipped premounted.

Tons of power! I can't imagine wanting more for any reason. Way more than you'd need for any normal track (unless you're doing a speed run or something). I hope to test runtimes tomorrow.

Low CG
http://rc.jeffjassky.com/galleries/b...t/IMG_7039.jpg

Countersunk heads for rear battery box mount
http://rc.jeffjassky.com/galleries/b...t/IMG_7040.jpg

Towerpro MG996R servo. Amazing bang for the buck. Behaves like an $80 servo. Actual cost: under $12 at Hobby City
http://rc.jeffjassky.com/galleries/b...t/IMG_7042.jpg

Mamba Max & CCBEC tray. Suspended from Motor Mount in front and supported by a standoff from the chassis in the rear. Note the purple standoff in photos above. Made from a baking pan. Holes drilled to secure capacitor, CCBEC & wires with cable ties.
http://rc.jeffjassky.com/galleries/b...t/IMG_7043.jpg

General shot of gearing and motor mount.
http://rc.jeffjassky.com/galleries/b...t/IMG_7045.jpg

From the front
http://rc.jeffjassky.com/galleries/b...t/IMG_7053.jpg

Some body shots. All I have right now is the RTR body. Good enough, I suppose. Plenty of cooling, obvioulsy.
http://rc.jeffjassky.com/galleries/b...t/IMG_7054.jpg

http://rc.jeffjassky.com/galleries/b...t/IMG_7055.jpg

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Lots of air flow to the heat sink here...
http://rc.jeffjassky.com/galleries/b...t/IMG_7062.jpg

Air flow from here as well.
http://rc.jeffjassky.com/galleries/b...t/IMG_7064.jpg

From the top
http://rc.jeffjassky.com/galleries/b...t/IMG_7069.jpg

Silly dramatic wide shot. I thought I should have one of those.
http://rc.jeffjassky.com/galleries/b...t/IMG_7070.jpg

Some clips of last saturdays races..

A fellow racer running a Neu 1515/1/Y/F on 4s (The blue bodied 8ight with the white wing).

Video 1
High quality: http://rc.jeffjassky.com/videos/feb-2-08/
Low quality: http://www.youtube.com/watch?v=DcZ62zMMwlw

Video 2: (My buggy)
High quality: http://rc.jeffjassky.com/videos/brus...ht_feb_2nd_08/
Low quality: http://www.youtube.com/watch?v=v_NGdjwChYM

The high quality video will require quicktime. If you don't have quicktime you can download it here http://www.apple.com/quicktime/download/

-Jeff

Great looking work! Jeff
How did you "size" (choose) the 2700Uf 25V Capacitor?
Is it spiced into the pos. and neg. with the ccbec and fan?

I would keep an eye on the bottom of the battery for marks from the holder mounting screws and maybe cover them with plastic or something if they are marking or touching the battery as the foam gives.

Enjoy your work and thanks for sharing

Well I'm not exactly sure how people decided to use the 2700Uf capacitor.. but I was advised by the electronic-techies on the rc-monster forums suggested that capacity. You want to over rate the capacitors voltage by at least 20% to increase life of the capacitor. I am using a 14.8v system so I decided on a 25v capacitor. The capacitor only puts out the voltage that's actually put in to it so even though it's rated as 25v it only puts out 14.8v.

It's connected directlty to the + and - battery terminals along with the CCBEC as you said, though the fan is running off of the output of the CCBEC. The fan is a 5v fan so running it directly off of the 14.8v battery would fry it. I have the CCBEC set to output 6.4v rather than 6v which speeds up the fan and also increases performance of the steering servo... though not too high to fry the servo or the fan.

Here's a photo from last saturdays races.. I had a few minutes to shoot between races so it's a little dirty :)

http://rc.jeffjassky.com/galleries/b...aper_thumb.jpg

very nice. what runtimes are you seeing?