ok, here we go. this thread will document my attempt at converting a century predator max to electric power. the predator max is a 90 class 3D helicopter that spins 720mm blades.

http://www.centuryheli.com/products/.../index1301.htm

my plan at the moment is to use a 12 cell lithium polymer battery pack to power this beast. i have not settled on a motor or speed control yet, but i am leaning toward an actro 32-4 with either an actronic 70A ESC, or the schulze 40.70.

here's a photo of some of the parts:

here's where i'm at in the process. it weighs about 3lb, 11oz right now (not including the battery pack).

Sweet, looks like lots of shinny alum parts!

But what about the big hole between the gear and that tray out front? (I have looked at the heli on the site yet)

Do they have CF frames for it yet?

Hello

I have been waiting for someone to do this conversioin since the Pred came out. Its such a sweet looking ship at a very good price, and it has inexpensive replacements.

Cant wait to see the finished product.

Carlo

century says they'll be releasing carbon frames soon, for a wide range of their helis. i plan to make new lower frames that will replace the two lower frame panels with a one piece panel made of G10 or carbon fiber. anyone know where to get a good price on carbon fiber plates? i need a 12" by 12" piece that's 1/16" thick (0.063"). mcmaster has them for about $54, and CST has them for about $52.

Hey Ben,
MJP Carbon has 12x21 "scraps" of 2mm carbon for $46. That sounds like a pretty good price.

Niiiice

So what do you think of the kit so far?


--jim

thanks, scot. that's a pretty good price. i think i'm going to do my first set in G10, just in case i screw it up or something. then when i know i have a good design, i'll make some carbon ones.

jim, i'm pretty impressed with the kit. everything seems very high quality. the swashplate is beautiful. the frames are not as heavy as they look. i was a little skeptical of the TR gearbox from the photos, but when i put it together, i realized how solid it is. the only major bummer so far is the canopy, which is very heavy. i'll worry about that later.

Ben74,
I think you'll find that the CF reinforced canopy on the Predator is lighter than ANY of the other 90 size heli's canopies out there. And, for that matter it's ALOT lighter than a plastic equivalent sized unit.

As for the CF upgrades those are being worked on currently. They will come with some nice features on them. Although, it is Century position that the CF frames are a DOWNGRADE in comparison to the benefits of the CNC metal frames.

If you are looking to save weight I believe a hollow mainshaft would be a good direction to go. Also, you might want to look into the "tuff strut" style landing gear that comes on the SE. You could shorten the skids by about 4" and save some weight there too.

Also, consider the CF upgrade "3D" fins as they are lighter than the stock solid CF fins.

Good luck and keep us posted. Century is watching your progress.

Payton Indermuehle
Century Helicopter Products - Field Rep

Oh yeah....

Just for the record my Predator Max weights 10lbs 7ozs with a heavily painted canopy and fins.

It started out at 10lbs 2ozs. That's pretty much the lightest glow 90 heli on the market

Originally posted by Lift


If you are looking to save weight I believe a hollow mainshaft would be a good direction to go.


Payton Indermuehle
Century Helicopter Products - Field Rep

Where would you find one?

hi payton. i'm not saying the predator is heavy, compared to other 90s. it's the lightest, which is one of the reasons i chose it. i'm just saying the canopy is heavy compared to what us electric guys are used to. my logo 20 canopy is made out of thin lexan, which is much lighter than the polypropelyene (milkjug plastic) that many nitro helis use.

my reason for making a one piece lower frame is so that i can install a motor mount for the actro motor. the actro needs to be supported from the bottom, unlike most electric motors. i doubt the new frames will save me any weight. coincidentally, it looks like the tip of the actro's shaft will fit right into the 5mm bearing that normally supports the starter shaft (i think?), so the motor will be supported at both ends. this should be a pretty easy conversion.

Ben,
Ok, just was confused on what exactly you meant by the canopy being heavy. I was sitting here thinking "man, they don't get any lighter than this". That is from a glow fuel dude's mindset......

Sounds like your going to have some fun! I can't wait to see the photos. Keep the updates coming....

Wow Ben, you're quick. If it was me, the Predator would still be sitting in the box. Looks like with words of encouragement we might see that EPred soon. Go Ben! Go!

Regards - Steve

Hey Ben,
While I made a new bearing block, I am still using the Raptor's original starter shaft bearing block area to support the top of the motor shaft. I had to change one bearing but that was it.

I got this idea from ChrisS...you can support the bottom of the motor with 3 standoffs that I mounted to the bottom carbon frame stiffener. Doesn't look like your Predator has one but you could probably make one or adapt one from another helicopter. Would be much easier than cutting new frames, at least in the beginning. Hope that makes sense?