Waldo,

Did you send 191557 some of your glue?

Hey,,, I can be a nice guy, But I don't know if I could part with my glue,,[X(],He might be making his own concoctions though[sm=spinnyeyes.gif]

191557,

You know if you start talking to your Twist and referring to it as she, her, baby, sweetheart, or beautiful, then it is time to get a ventilation fan in the shop!

Adam

Adam,,, I have 9 planes, and I sweet talk them all,,,[sm=wink_smile.gif] maybe I should see someone,[:-] If I cut a ventilation hole in my ceiling,, My wife would fall through onto my planes.[sm=omg_smile.gif]

By the way,,, I did like 191's episode,,, that is one thing I love about this thread,,, you never know whats coming at you next.

[sm=lol.gif] you folks are too much

Quote:
You know if you start talking to your Twist and referring to it as she, her, baby, sweetheart, or beautiful, then it is time to get a ventilation fan in the shop!

Adam



I have six more Girls still down there with the DREADED TWIST & I am worried about my babies. I am sending in the "A" team to make a Rescue attempt. This guy works alone.

Now he looks like he is ready to jump in the ol Sopwith and get down to some business[>:]

Now's there's a handsome young man that I bet makes his daddy proud!

Thanks & yes he does.

Back to some serious business. I have been debating this for some time & decided I would ask for some Expert advise from you guys, Down can fly a tub with a 350 in it & send Waldo a bag of sawdust & some epoxy & he can build a airplane, then there's all the rest of you guys with your vast amount of knowledge . What problems would I run into if I were to try & make the T---T a Bi-Plane ? I just think that would be to cool to bash it a little & see what would happen.

Has anyone done the electrical mod for the Twist 3D yet?

I have an AXI 4120/14 and two 4S 2100 mAh packs to run in parallel for this project.

This may have been discussed earlier, before I joined the forum. If so, could you just point me to where the discussion starts?

If it hasn't been discussed, what is your opinion??

Bob

look back to page 207. you'll see posts by Adam G on his conversion of his twist to electric power.
Jeff

I believe someone mentioned doing a Bipe on the T_ _ _T earlier in the thread,, not too far back but back none the less, I don't believe anyone ever got back to us with any reports about it though.

Personally, I think it would work out just fine, I believe the top wing you would want about a degree of negative incidence, and the bottom wing at 0. Good luck,,, go for it I say.

N1EDM,

I converted a .60 size Twist to electric. I used a Hi-maxx motor that is equivelent to the AXI 4130/16, and two 3 Cell 4000mah batteries ran is series to create a 6 Cell 4000mah battery.

What I would recommend you do is get a watt meter. I have one made by eflight, but I know the Astro one is excellent as well. They both measure amps, volts, and watts when you hook them between your battery and speed control. Amps x Volts = Watts, and to be able to 3D with unlimited vertical you will need 150 watts per pound with a low pitched prop. I am getting just over 150 watts per pound with my new 18x6 prop, and I am sure it will be more than enough.

If you are using two four cell lipo's ran parallel, you will end up with a 4 cell 4200mah. 4 cells produces about 16 volts of power under load on a fresh charge. This is a complete guess, but I think your .40 Twist will wiegh in around 5lbs. If that is the case then you will want 750 watts for 3D power. So you will want 16 volts x 40 amps = 740 watts. I will check the AXI specs, but that should be within the limits of the AXI 4120/16.

Once you know you are within the motor specs, the best way to find out is to bolt the motor down, and start testing different props with your watt meter. I started out with a 13x7 prop and found that spinning the smaller prop was only pulling 30 amps, and about 730 watts. I then stepped up to a 16x6 and found that I was pulling about 41 amps, or 890 watts. This wasn't too bad, but again not like what I am used to with a .61 on a .40 sized Twist. The 18x6 is now pulling 51 amps, and about 1100watts. Now I am above the 150 watt per pound threshold, and should have awesome power. The down side is the more amps you pull, the quicker your battery wears down. I am getting a 15 minute flight with mixed flying, and it will drop to 12 minutes with the bigger prop.

All the numbers I am throwing out are at wide open throttle. The only time you will use it is for hovering, climbing up for a spin, or harriers. Most of the time half throttle or less is great. You may have to extend the landing gear. You will be using a 15 or 16 inch prop.

As you can tell, I like talking about big electrics. Please let me know iuf I can be of further assistance. I am going to run some numbers for you on motocalc, and I will post them in a bit.

Good luck with your conversion.

Adam

N1EDM,

I ran some numbers on this site:


http://brantuas.com/ezcalc/dma1.asp

Go there and plug in you batteries, motor, and prop and see what you come up with. It looks like the 4120 will handle up to a 6 cell Lipo, and 70amps. The way the numbers look, you will probably want to go to a 5 or 6 cell lipo. The load of the big motor brings the volts of you battery down to less than 14 under load. So you even with 40 amps, it says you will pull mid 400's for watts.

Here is an example:
16x6 APC prop

49 amps

584 watts

You could go this route and have a very nice sport plane, but you would be lacking power for 3D. A 5 or 6 cell would make a huge difference in power, but I don't know that you would want to buy more batteries. Maybe the plane will come out lighter than I think. It looks like your motor and batteries will wieght about 2 pounds. That leaves you 3 lbs for speed control, reciever battery, and plane. Run the numbers, and see how you do.

Adam

Thanks for the info guys.

Actually, I've already been flying this setup in a Funtana 40, but the Funtana is just a little too much airplane for the 4120. It flew OK, but more like a moderately agile sport plane. I was looking for something a little bit more lively, which is why I decided to electrify my Twist. If my numbers are correct, the Twist setup will be about one pound lighter than the Funtana 40 setup.

I already have the system I described and (obviously) flown it as a 4S2P at 4200mAh (20 Continuous, 30 burst). I really don't want to invest in another battery pack right now.

I've got the Whattmeter from Astro Flight, and you're right, it's worth its weight in gold. I found that a 13x8 worked best for my setup on the Funtana 40, but it may not necessarily work on an electrified Twist.

My main question was, what was the pilots opinion of the electric Twist 40 if he were running an equivalent system to the one that I described.

Thanks,

Bob

You might check the reviews done for RC UNIVERSE - they did a glow and electric twist in one article.

Thanks, I'll take a peek.

I found it at http://www.rcuniverse.com/magazine/a...article_id=408

Bob

N1EDM,

Didn't know you were currently flying with that set up. It should still come down to watts per pound.

I decided to get up early this morning (6am), and see if I could beat the wind. It was a beautiful morning, and it was dead calm with clear skies, and temps around 26 degrees. Being it was so early, I chose to bring 3 of my electrics so I wouldn't wake anyone. Luckily I took some pictures before I started flying, because you can see by the last picture, it may be a while before I get a picture of her in one piece.

This is what happens when your ESC cut's the power to your motor due to low voltage when you are hovering 20 feet above the ground. The new prop is awesome, but obviously flight times are a bit shorter. I will have to account for that next time.

Adam

Sorry about the loss, Adam. Like they say, put it in a corner for a week or so, then bring it out and start fixing it. It won't look so bad then. It'll be back flying as good as new.

Bob

Adam Sorry for the crash,, But in fact,,,,,,,, the T_ _ _ T was named for this particular reason now it looks T_ _ _ Ted, I'm sure you'll have her back together in no time... Good luck, and I know the feeling of losing power in a hover 20 feet or less off the deck all to well,, it never ends pretty, but I always glue her right back together and do it again.... maybe I have been smelling epoxy for too long,,, BUT I LIKE IT

Flight report 10/28/06

GROUNDED UGGGGHHHHHH [:@][:@][:@] DANG WIND AND POURING RAIN ALL WEEKEND.
I vowed I wouldn't miss anymore flight time due to weather this season,, but I have to hang my head in shame[:-] as I just couldn't do it.. winds were gusting up wards around 35 - 50 which is usually Okay, but the pouring rain wouldn't even let me out of the car,,, Now I must Jones until next Saturday[sm=cry_smile.gif][sm=cry_smile.gif][sm=crying.gif]

Sorry I can offer no advice on the Electrics as I only have 2 smaller electrics with a 3 cell pack and I'm just learning how frustrating the electric field can be in this hobby,, Like why won't my battery charge, it has about 6volts on it and it worked just fine when I took it out of my 580, so I just put it in my new foam yak. I'll figure it out,,, after all I am also a half a##ed electrician.

If you have a 3-cell Lipo pack that reads 6volts then you have a bad pack. It's ruined if it's that low. Cell voltage isn't supposed to go under 3v/cell so it should never read below 9v under a load. Smart ESCs will prevent that from happening. It won't charge because your charger has "smart" circuitry in there to prevent things that could cause explosions/fires... like charging a pack that's too low of voltage.

NAbit it all [:@] Thanks Ghee

Don't mention it! Unfortunately for my Twist, I have delved into the electric world for the last couple of years. I've learned quite a bit... some lessons were learned the hard way like you just learned.

Where's all this wind coming from? (Oh, I forgot.............it's election time!)

I Tell you the last 4 weeks have been windy as hell, I'm hoping for one more some what calmer of a day, before we get snowed out of our field, Thats all I'm asking for, I have had a couple of mornings during the first flight where there was no wind and 10 minutes later during the same flight 20 MPH gusts then right into 25 - 30 winds for the rest of the day, and last weekend was just ridiculous, but we went up anyway, then this past weekend we were completely taken out and couldn't do anything, Not That it isn't fun to fly in the wind but even Waldo likes it calm every now and again.

This is exactly how are season started out this year with 5 weekend rain outs right in the very beginning. [:@][:@][&:][:@]

Its almost flight simulator season, I'm going to have to set the winds on high and visibility to 10% if I want to feel like this years flying experience.