I agree that the RCCA website has vastly more information on people trying to build a competitive SSC electric setup. It has been my experience with my efforts that the planes come in about 4oz heavier and drop about 700-800 rpm during the round, which to me is significant. Still, there are people such as Lee Liddle that have been very competitive in SSC using electrics. Good luck.
I've done a MESS of experimenting.
I did a conversion of a battle axe, then the texasflugewerks eCobra/eFalcon.
Then a Kirk Adams Rapier that he converted to electric. I then did a 2nd fuse. Kirk's design was the best so far but you gotta be on the east coast so you can get his wing. eCobra/eFalcon is the easiest to do in Electric but not the most rugged (the least rugged actually cause everything is exposed in a mid air. The eCobra wing will run into the ESC if you don't keep the wing tight.
I have been using the hobbyparts monster power 15 as well as the turnigy 1100Kv motor. Turnigy is lighter, but I had ordered the hobbyparts motors first.
I am using the hobbbyking SS 50/60A esc cause it's over rated and cheap.
I"ve done 3 contests so far. I would say that the electric loses power about 3 minutes into the flight to the point that vertical climb is a handycap. I"m reworking a new battleaxe fuse to try .15 nitro just to see how differently I do with it. But I will still fly electric I think as well. Unlike others, I NEVER have a problem getting into the air. After 2 contests I'm pretty well prepared with batteries, charging and such that I launch about 30 seconds after the "start engines" mark, climb out then throttle back till about 10 seconds before "start combat".
I"m still a newbie but I"ve placed 4th out of 13 pilots in the 2 of the 3 contests. My 2nd contest was PLAUGED with electrical/mechanical problems and I did not prepare as well. I have never missed a "start combat" yet, but don't think electric is giving me any other advantage other than consistancy.
I've been on this one for a while, and tested a few motors. There was a progression of tests moving from 36mm inrunners to Turnigy SK outrunners. It all depends on which battery you want to go with. I've test run 3, 4, and 6 cell combos.
I've run several of the Great Planes Ammo inrunners on 3 cells. They've discontinued the 2250 kv model that I use. Other manufacturers have appropriate motors. These work, but the overall power system weight is high.
The Turnigy 35-36-1400 works on 4 cells. You'll need batteies of at least 3000mah capacity to keep this in the air for the full heat.
The 1100kv Turnigy Dane mentioned is probably the most logical unless you have the proper 4s batteries laying around anyway. Everyone uses 3s 2200's for various other planes.
Your performance is going to come down to airframes once you settle on a power system. Being in the hometown of the Battle Axe you'd think I'd be using them...No slight against them, they are great, and I wouldn't hesitate to use them if I were still flying glow. However, you're going to sacrifice alot of armor to get your weight down. That's why most are going with a flying wing design. I've been working on a couple designs for a while, but my CNC machine is possessed by the Devil and refuses to operate properly, so it's been at a standstill for 2 years now.
I'm relatively new to SSC and am in the process in putting together a kit that I picked up at Perry a couple of weeks ago. I've been told it's a Lethal Weapon version. In addition to try it out with a couple of glow engines I also wanted to try an electric configuration. I have a Turnigy SK 35-30 1100 that you mentioned and a compatible ESC. I was wondering what props you are using with this configuration?
Yes, the 8x3 is the only legal prop in SSC regardless of power system. The electric system that I mentioned will swing the 8x3 at well over the 17,500 rpm limit.
I set the rpm every time I change batteries using throttle travel function in my radio......just dial down rpms to 17,500 and after 5 minutes of combat you will still be in the mid 16's.
Be sure to balance and trim the flashing off of the prop.....MA is famous for being out of whack from the factory and they all require whittling to get um up to par and to keep vibration down on the electric motor.
From you're earlier post on your E-SSC configuration I was assuming that you were running the two 3S batteries in series to get the necessary RPM. Is that correct?
As it turned out I didn't have an 8x3 prop. Since I was traveling up to Richmond this past week I stopped by K/C Hobby near High Point NC. They are great folks and have the most well stocked shop that I have found anywhere around here. They had a ton of props, but no 8x3. I picked up a couple of 8x4 and 9x4 props to experiment with in the mean time. Where to you get your 8x3 "combat" props? Straight from MA?
I'll certainly take your advise on balancing these props and will let you know how this "first try" works out.
I get 8x3 props from my local hobby store.......They are available from tower or most of the other large domestic hobby retailers or from MA.
The battery config is 3S2P
Keep in mind that the power system that I posted was assembled specifically for SSC using only an 8x3 prop. It is a reliable, proven combat package.
I have no idea what kind of performance you will get using a 8x4 or a 8x5 and you may not be pleased......just check that you are not pulling too many amps and whatnot.
I'll definitely be testing these two props first. Awhile back I built a test stand using a Medusa analyzer (bought it just before they went out of business). It's a great learning tool. I'm looking around for a 8x3 also. It looked like MA sells direct so I can probably get what I need from them if need be.
As I said, I'm still learning, so I'm really fuzzy on the math that tells me what rpm I should expect. Are you getting the 17,000 you mentioned earlier with the 3s2p? According to the specs on HK for the 35-30-1100 it has a voltage range of7.4V~11.1V (2~3S Li-po) so the 3s2p would be suitable. On the other hand I've seen several others note that they are using up to a 6s. Wouldn't that smoke the motor, or are the published specs wrong. Some of the threads on other forums have me quite confused on the max voltage issue.
It's FINALLY a decent day here in the NC mountains so it looks like I'll be able to work some of the kinks out of some of my long dormant servos today. <G>
Thanks for the update. That helps a lot. I'm now much more comfortable with giving the new 6s I just received a try. I have a feeling I'll be running around at half throttle as I get used to it. <G>
I also just recently discovered that the FMA Multi 4 charger I have won't handle the larger batteries. I wasn't thinking about that when I was mulling over the 6s versus 2x3s question. Do you have a favorite charger for these larger batteries, or for any of the LiPos for that matter?
I just tried HobbyPartz for an order and it was painless. They have the Thunder AC6 on sale for 42 bucks. I haven't seen much negative on this one on the forums. Any thoughts one way or the other on this model, or brand?
I use a icharger 3010 and parallel charging cables so I can charge up to 6 packs at a time. I charge at 2C so 6 batts at 4.4 per is 26.4 amps.....at a contest I will charge 2 packs at a time at 8.8 amps.....only takes a few minutes to top them off.
I do however carry 18 batteries with me to each contest, enough for 9 rounds without charging so I'm not under the gun to get um charged before the next heat.
I had to get a new power supply that would handle the load so I bought a server power supply off ebay that will give me 57 amps, 700Watts at 12V. I actually have 2 that I can connect in series to give me 24V if I need.
I don't know anything about the charger you mentioned, but I have ordered from hobby partz and it too was painless.
Some of the guys I fly with use turnigy chargers from Hobby King and they seem to do fine.
I was just looking at the different models of the icharger on progressiverc.com that I saw referenced on RCGroups earlier. The 3010 looks to be a pretty heavy duty charger, but then for your needs I can see why it would be useful. I was reading about the 106B and 206B which seem to do about everything I'm looking for now. I'm not likely to have to charge more than one battery at a time so they certainly ought to be adequate. I'm currently using the FMA 4s and Multi4, but they won't do more than 4s and won't discharge. I found that feature missing when I was trying to store my LiPos over the winter.
One feature I like about the FMA chargers is their monitoring software. I see that the icharger uses a program called logview. Have you used it? Is it useful?
I like the ichargers really well. The 20 amp model would be a good one too. My 3010 was a plug and play. I pulled it out of the box and immediately went to charging.
Very user friendly for me and there are a ton of features that I will never use.
With alot of the new batteries having charge rates up to 15C a powerful charger will come in handy.
The more I browse around, the more I like the looks of the icharger line, specifically the 106B and 206/8B models. Not too much more for the 20 amp version as you suggested. Junsi also seems to have a very active support presence on RCGroups which is a big plus.
EPBuddy seems to be a prominent distributor. Are you aware of any others? I couldn't find any easily. I see that HK carries the line, but I'd rather pay a little more to be able to deal directly with a distributor that provides support. I have the impression from their web site and some peripheral comments that EPBuddy will provide that. Any thoughts on them or other distributors?
I have an iCharger 106B+ as a backup but mostly use a 3016B.
I got it from epbuddy along with the 3S 6 port balance adaptor and Deans 6 port adaptor for parallel charging.
As mentioned. Fly in series but charge in parallel.
I use the Hobbypartz Gens Ace and I can parallel charge at up to 5C and get all charged up in about 8 minutes. YOu still need extra batteries "just in case".
Lots of pros/cons with electric.
I've yet to miss "start combat" with my electric though
My best fuse design has the batteries all under coroplast. My electric battle axe and eCobra both lost batteries last year from mid airs. I prefer the batteries protected.
In a lawn dart type crash, the worse I'm likely out is $16 for the motor. I just spent 1.5hrs cleaning up a muddy engine. For electric, I just swap motors and toss the motor in a bag.
EPBuddy and Progressive are the only two stateside that I'm aware of have the icharger. There may be others. There is a very active support group for the ichargers on the forums and thats one reason I bought one.
I bought mine from HK and had it shipped with some more stuff I bought at the time and was still cheaper than buying from a vendor here. If I ever have warranty problems then it may be a pain, but so far so good.