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paladin-34's blog
Posted by paladin-34 | Jun 02, 2014 @ 12:29 PM | 1,420 Views
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Posted by paladin-34 | Apr 02, 2014 @ 10:50 AM | 1,367 Views
I have conerted alot of my liquid powered planes to electric and am ask all the time what will work in my>>>>>>>?

i'm a liquid power guy! always will be! so how do i convert to electric? when i look at a model plane i figure out what liquid power plant i would use. in this case i will use two planes my Evergreen P-51B and Great Plans Ultra Sport60.

the P-51B was powered by a o.s.120 pumper four stroke turning a 15x10 for 6 years. this os was 20+ years old with no part availability and the pump on the back had stopped working so i plugged it and ran regular induction for the last few years, rpm's where 7700-7900. those who saw this engine will remember it cause it sounded like the 5 o'clock charley of M*A*S*H.

we know:

(pitch*rpm)/1056 gives prop speed
(10*7800)/1056 = 73.8mph

now i'm going to look for an electric prop., battery, and motor combo that will give me the same tip speed.

I chose a turnagy 5065-350 turning a 15x 8 prop on 8s5k25c batteries. we need to talk about batteries here, it is very importand that you understand that battery voltage drops when you apply load. so even if they check at 4.2 volts / cellon the ground the motor will never see that. further more as the batteries are drained their voltage drops. thus your rpm's drop. so to figure out tip speed i use 3.5V/cell this is actually a mid- flight voltage but it will keep you from going below the performance you want.

so:
motor RPM =KV*(cells*3.5)=350*(8*3.5)=9800rpm's

...Continue Reading
Posted by paladin-34 | Dec 13, 2013 @ 12:56 PM | 2,746 Views
my son and i dog fight regularly we used to use an evergreen P-51D converted to B(my plane) and a Marks models P-51D. with the advent of smaller cheap foamies we had gone to PZ Me109's since they came out. now those models had motors that did not last long so we replaced with Turnagy sk3548-900 turning the stock prop. with that power the plane will takeoff without a conplete turn of the mains and go vertical out of site 'just like the real one'. the only limitaion being the wing main spar ends about 8 in from the tip and if over stressed it will come off. but we never had any problem there cause when dog fighting we are manuvering so much it never break the tips off. anyway those planes are 3 years old now so we thought the FMS Me109 may be a good replacement. when banana put them onsale for 190 buck after thanksgiving we each bought.

first change was to install a 100amp Dlux speed control because we planned to use 5s if the motor could handle it.We flew off the stock speed control for some time maybe 30 flights between us and fund it was easier to handle on takeoff because of the ramp up curve was slower at the bottom end.

my fw was the first one we tryed on 5s and it did not fair that well so i added some scoops to my me109 prior to trying 5s. while i have only 4 flights on 5s that is one more than the FW got and the motor is showing no problems.

also in an attempts to tame the ground handling we installed the Orange 6channel 3-axis gyro rx. my son has his on all the...Continue Reading
Posted by paladin-34 | Dec 13, 2013 @ 10:33 AM | 1,754 Views
Maidened in nov12 on 4s5000a25c and the landing gear were not working. it was odd, they would come down and be fine on the ground could not make it fail. but on the genilest landing the left gear would pop off the cam and fold. she flew very nicely but slow. the flaps worked very well!

i had modified the flaps turning the controll horn around to give a stronger endpoint control. and they provided the amount of drag i expected with no wallowing from spft endpoint control.

the next time i could get out was march and i had added a 6v back up battery. first time i plugged it in i smoked the left retract unit. the right one still worked at the field but not soon after it seased to function but without the puff of smoke the other gave. so i bought the new est replacements that were available and installed them. i had to modify the plastic plate in the wing to accept them.

befor i had ten flights on this the tail wheel went walk about so i replaced it. so at this point i have yet to get more than one flight per trip to the field, and it always left with a mechanical failure and i was getting to the point of leaving it home. when it ran off 20 flights without a problem.

during this time i decided it was time to give a 5s battery a try. it did not take long even with me babying it at first for a tick to develope. so upon investigating the magnets had broken away fro the bell and were moving back. i pushed them back into the notches for them in the front ofthe bell and...Continue Reading
Posted by paladin-34 | Dec 13, 2013 @ 09:41 AM | 1,682 Views
well it has beeen awile.the GP Fokker DR1 flew great on the setup i installed.I actually sold it prior to testflying it but have seen it fly and it has a really good flight envelope. the extra nose wt causes alot of ground looping on landing but chriss is ok with that. the reason i slod it was i like to fly when i go to the field and the triplane has a mind of its own, specially in a crosswind. if you don't fly in crosswind you dont fly.

Last year I built a Hanger 9 Spitfire i used the recommended setup Power 60, and a 6s battery. after a number of flights i was not happy with the power system cause it just did not have the ponies i want in a fighter, the flaps did not react the way they should, and the color scheam is so dark it is silouhette regardless of available sun.

i was given the impatice to change the power system when on one of those days with large wind deltas it fell out of the ski on takeoff. i remember waiting for the pressent gust to subside prior to advancingthe throttle. it rolled a good distence then lifted off, before i go a foot off the ground it came back down on the mains hard. enough that everyone looked to see the crash. the prop had broken both blades and the LG fairings were gone for the extent of the damage, and it sat there on all the wheels. i would like to say wind shear, but having never seen one before i got to go with pilot pulled it off to soon. well i know how to solve that i went to the power system i've had a great deal of luck with. Turnagy 5065-380, 8s, 100A speed control and now we dont have any issues with wind on ROG.

the flaps come down as far as the stock setup will allow i thibk it is close to 40 degrees. but when i add flaps the plane will not come down, that means not enoughflap. i've since been looking at pic's of real spits with flaps deployed and it looks like they are using 70 degrees. that means removing the stock system for flaps and mounting the servos in the wing. which i will tackle soon.
Posted by paladin-34 | Dec 01, 2010 @ 12:08 AM | 3,002 Views
5dec10
Made a y harness, replaced the E &R servos, removed the rx batt (not sure I like that). But the removal of the rx batt removes 4oz at 4in from the nose. Changing the moment to 64 and a weight delta of 6 oz.



2dec10

Summed the moments and I'm 80 ozin heavier in the nose. That would required a little over 2 oz in the tail to bring it back to the same cg. Think I will only add 1 oz cause I hate adding wt to the tail. Need to solder up the speed control.


30nov10

I disassembled the GP (60in) Fokker Dr1 today, removed the Super Tiger G90 and fuel tank. I have installed a Turnagy SK4260-500, it looks like I will have enough room to put a flight max 4000mah 6s 20c on either side of the engine mounts for 8000mah total. The G90 swung a 14x6 prop at approx. 9000rpm thus:

(((9000x6)/12)x60) / 5280 = 51mph

The Turnagy with a 6s can turn a prop:

22.2x500 = 11100 so I think a I can get 9000 rpm’s on an electric 14x6.
My power calculator:
From the hobby king comments 13x8 prop 9566rpm on 20v draws 50a
14x6 yields 9530rpm and 55mph
14x8 yields 8650rpm and 66mph I think this will be the one I start with.

Joe
Posted by paladin-34 | Nov 02, 2010 @ 09:39 PM | 3,132 Views
2nov10

I test flew the GP combat Corsair with a Turnagy SK3548-900 turning a PZ Me109 prop., plush 60Amp speed control, and Rhino 2150 4s1p. it was cloudy, windy, and all the flying was done in silhouette so after a few loops and verifying hands off flight I landed. It had good vertical, the loops were 200-250 ft diameter and it was running out of speed at the top. Landing was uneventful, it loses altitude easily while maintaining a good flying speed.

I’ve finished installing a Turnagy C5065-350 turning a 16X10e prop. in my Kyosho Focke Wulf Tank 152 H using a castle ice 100 speed control. The batteries will be 6 Turnagy nano-tech 2200mah 4s hooked up into 8s3p 6600mah. The purpose for this is to reduce the cost, and of replacing bad cells.


3nov10

Attempted to fly the Kyosho Focke Wulf Tank but the motor would only come up to 100 RPM’s then cut out, all servos were working great. Remove the red wire from the T plug in the RX and the servos all work correctly the motor is dead. The motor was running off the rx bat so I need to go through each piece of the wiring to rule out the possibility of an open.


5nov10

Kyosho FockeWulf Tank 152 H:
Checked all harnesses, all the easy ones to ge to were good. So finally I had to remove the cowl to check the speed control, as visions of delay crossed my mind. I pulled the cowl and immediately saw the positive lead had fried from the deans connector. At first I thought I was lucky to still have the...Continue Reading