My custom E-LX1

Well, here is my custom version of an electrified Ofna LX1. The path to get here was very different than most follow. Let me explain. (sorry for the long back story)

My first 1/8th scale car was the old Ofna HODR back in 1995. I ran it back then and loved it. Absolutely loved the sheer power ouput of the big cars back then. Well life intervened and I hadn't played much with my cars for a while. A couple years ago I started to get back into RC, but mainly with airplanes. Well, I eventually got out my old car stuff and have been slowly working on them. (you can check out my converted Electric Nitro Hawk posted here:
http://www.rc-monster.com/forum/showthread.php?t=21358
)

To make a long story short, I crashed the HODR pretty good, and was out looking for replacement parts. I noticed that many of the current Ultra and LX parts could be retrofit to the HODR, and so I began upgrading the HODR. I was almost to the point that I had an entire separate drivetrain. Around this time I began reading about people converting their 1/8th scale buggies to electric. Sounds fun I thought. I made the decision that I would actually create two cars with all my stuff. One would be gas with the old HODR mix drivetrain, and the other would be electric with the mostly new LX1 drivetrain.

Like the Nitro Hawk conversion, I decided to fabricate the motor mount at the machine shop at work, but it eventually turned into a much bigger project as you can see. (By the way, this project was actually started way before I started the Nitro Hawk conversion. It took a lot longer)

Now for the oligatory specs:

Motor: KB45-10L 1800Kv from Hobbycity with turned down shaft (Had to use the dremel while running it. I couldn't for the life of me get the endbell off to remove the rotor. Otherwise I would have put it in the lathe.)
ESC: Castle Mamba Monster Max v3 (Got it for a good deal. Would have gone for the Hobbywing EZ-Run 150A ESC otherwise.)
Battery: 6S1P A123 pack (taken from a Dewalt 36V pack)
Servo: HXT12k metal gear servo
Assan X8R4 2.4Ghz micro receiver
15/51 pinion/spur combo

In all I designed and machined the following parts:

4mm aluminum chassis
Motor Mount
Battery Tray
ESC platform
Top plate
Rear chassis brace
Steering servo plate
Front Top hinge pin retainer
Rear Bottom hinge pin retainer

Whew, and I'm not even done. Last thing to do is a wing mount (although I think I may just buy that - I have a lot less time to play at work now). Total weight as it is now is about 5.75lbs

One thing to keep in mind when checking this thing out is that I don't do any organized racing. It is for me to have fun with and bash (and maybe race out in a field with a friend or two) - hence the strong bracing and full length top plate. I don't want to destroy any more drive shafts or chassis. I really like the Ofna Ultra derivative models for bashing. They have been very durable for me and parts are super cheap on ebay.

On its first outing, I had a blast, but out in the street in front of my house, the buggy had too high of a CG and too much traction - it would roll over with just about any turn at higher speeds. That is why the shocks are now all scratched up - I hate that. After adjusting the set screws to lower the ride height, it does a lot better. I haven't got it out in the dirt yet, as I wanted to finish the body first to give it a little protection.

I have the MMM set with very conservative punch settings, as anything more is almost uncontrollable from a stop. I do have some room to grow on the pinion, though. After a full battery's worth of running, the motor is around 125 and the ESC and Batteries are barely warm - around 90. With my Watts Up meter hooked up, the peak amperage was at 56A.

This thing is insanely fun. Electric power ain't what it used to be, that's for sure. Without a doubt, it will beat the pants off my buddy's Hyper 7.

Hope you enjoy the writeup and the pics.

-Jeff

A couple more pics for you.

[lincpimp]

Very nice looking conversion. An ofna buggy was my first 1/8 scale vehicle and my first brushless conversion. I will always have a soft spot for ofna products, they seem to be well designed and well made, and cheap too. You di a great job making everything neat and tidy with the setup.

[snellemin]

Very nice built man. I'm diggin your battery box.

[Overdriven]

Nice job. Definitely better than the ofna LX I threw together. I always wanted to make mine nicer like yours, I'm diggin the center braces, but was having too much fun beating the hell out of it. Have fun

[zeropointbug]

Did Mike make you that battery tray?

Do you have an eagletree? You should be getting a conservative 1100watts from that battery. I am using a 7s1p pack in my Revo, and I am so surprised how much juice it can dish out, and just barely warm after a hard run.

[littlegiant]

Nice, what is the weight of the buggy?

Thanks for the compliments. This thing really did take a while doing it here and there at work.

The battery tray does look a little like the ones available here, but I designed and built it. Nearly everything was taken from scrap material laying around the shop. The battery tray was one big hunk of what I think was PVC. Not the strongest stuff out there, thats for sure - that's why the sides are pretty thick.

Total weight is around 5.75lbs. Electrical measurements were taken using the Watts Up meter ( http://www.hobbycity.com/hobbycity/s...yzer_(Watts_up) ). It will record just the max Amps and wattage, and show total mah usage. Not quite the eagletree, but it works well. It didn't look at the total Watts on the last run, but it should be right around 1kW, as the voltage sags a bit at 60A.

I personally think the ESC tray is one of the cooler things on this build. It is just a simple sheet metal design, but it was the first sheet metal part I'd made using a 90 degree punch/shear and press brake - gotta love perfect bends and crisp, straight cuts. The aluminum standoffs raise it up to get more airflow and I really dig the built-in switch mount. Sure the motor mount and chassis are more complicated, but they are just machined - I love learning to use new tools.

If anyone is interested I can post a screenshot of the Solidworks model.

-Jeff