Ok here is quick build log on the Jpower 50mm T45 mini EDF. I had a Wicked 4800 wemo combo sitting on my bench from my F86 upgrade so decided to try a 4800 4S combo instead of the regular 3S Wicked 6000 combo.

Motor: Wicked 4800
Fan: Wemotec Microfan 50mm
ESC: Pentium 40
Lipo: 4S1800 20C

Alternate setup:
Motor: Wicked 6000
Fan: Wemotec Microfan 50mm
Lipo: 3S1300mah 40C or 3S1800 25C
ESC: Pentium 40

Don

page 1

page 2

Don,

Nice build as always...


Your not nervous about those ESC wires passing right over your elevator servo though? It looks like the servo arm may catch on those shrink wrapped sections right above.

Actually the battery wires on plugged in can be pushed to the side quite easily. I will post a photo.

I did maiden the model today and it flew very well. Speeds doppler right at 90 mph on a fresh lipo but all I had was an older 4S 1500 25C lipo. I am guessing with a better 30C lipo it will be closer to 95 mph.

This model does suffer from excessive tail incidence as the case in the F86. My CG was forward of the recommended position and it was tail heavy on the maiden. I moved the lipo forward and it was perfect. I am also certain the excess drag of the incidence is also robbing me of some mph as it is eating power.

I will post my throws and some additional photos shortly.

Don

OK here is how the lipo wire is routed when I fly. The other photo shows my CG position. It is 1 3/16 (30mm) from the wing line as seen in the photo. The plane flies great that way and does not act nose heavy at all. The stabilizers really need about 2 degrees removed and the CG moved back. Not sure why some of these they have a lot on tail incidence built in as the others are essentially zero.

I flew a 3 minute flight today and put back in 1300 mah so that come out to an average of 26 amps or about 375 watts on the 4S. That is close to what the Wicked 6000 on 3S gets and I expect the 6000 combo on this jet to be about 80-85 mph so I think that is a better setup if you as me.

Don

My T-45 is still bone stock (except for the steerable landing gear I improvised), but I'm reading this thread closely, because the stock fan on my T-45 is very noisy, so sooner or later I expect to drop in the Wemo combo cannibalized from my F/A-18. (I am retiring the F/A-18 because the thing went into an out-of-control, locked-in spiraling dive on me after losing steam from a vertical climb...damage was fixable -- but I figure why bother, if the plane has a nasty habit like that.)

On my stock T-45, I am using the recommended 50mm CG, and it feels right for me. The tailplane incidence seems right too -- the elevators are perfectly faired to the stabs at neutral trim. Quite different from my upgraded F/A-18, which needed a ton of uptrim, until the elevators were angled substantially 'up' relative to the stabs. Don, I wonder if your different experience has something to do with the increased power/weight/speed of the upgrade? Or just personal preferences and different flying style?

In fact, my T-45 maiden was the most uneventful, perfect maiden I've ever had. Right away it felt like flying a plane that I had already wrung out and needed no adjustments whatsoever. Throws -- perfect...CG --perfect...trim -- I think I put in ONE click.

The CGs ranges they give work fine for stock power as that is how they were designed. CG and incidence are related to each other. The more incidence, the more forward the CG will have to be if the speed is greater than the designed trim speed. Why the F-86, Mig 15 and T-45 had so much tail incidence makes no sense to me. The L39, F35, F16 and F18 have little incidence and fly fine with higher power at the stock CG locations. My T45 has down trim and a CG way ahead of the stock location and does not act nose heavy at all. A setup like this is draggy because basically you are flying around with up elevator and adding nose weight to hold the nose down.

Yes what you say makes sense. As to the planes you mention with incidence -- the F-86, Mig 15 and T-45 -- I see a pattern there. Those are the planes with the fattest fuselages, and so they are draggier, and consequently slower-flying planes. I'm not an aircraft designer, but wouldn't a slower-flying plane need more tailplane incidence, to hold that wing up in a higher-angle-of-attack position, for slower flight? Just a thought.

Do you have a template for the thrusttube you made? I just retired my f-16 and I want to put it's guts into my t-45 airframe. I will only be running my 5400 combo in it so I would figure the thrust tube may help a bit.

This should be it.

Don

Hey Don! I have a few more questions about this build. First would I want to change my cg to your recomended 30 mm (1 3/16") from wing line if I am using a 5400kv wemo combo and a 1300 3s lipo. Second when ballancing your t-45 did you hold the model upside down or rightside up? Thanks again for all your help So sad that the wemo fans are no more. I hope you find a wemo replacement in the near future.

I would go forward with any setup with more than stock power. It is safer with a forward CG, you can always move it back if you need too much up trim to fly. I balance right side up. On models like this I hold a 12" ruler on edge in my hand then sit the model on it with the other hand.

In regards to the Wemotec issue, I already have a different 50mm fan on the way and some new motors for it. I had once researched an alternative fan unit before as I had delivery issue once in the past and thought that was a one time thing but it seems not to be the case. The new fan is basically like the stock fan, 6 blade but made by a different company and the motors I am going to test for it are actually inrunners made by the same company who made the BI3600 motors I was selling for 70mm fans. Since these models need about 350 watts to make them fly well an inrunner will work OK. I will post more when I get all the items in sometime in the next week or so.

Don

Thanks again for all of your help Don. My T-45 flew great this weekend. I am very pleased with this little jet and your combo I have in it. I can't wait to get one of your new combos. I would like to try one in my F-35. I know you have not tested them yet but do you think these hold up to or be better than the wicked wemo combos??

The wicked wemo to me is the best combo especially at higher watts. This new fan is one I have no experience with but it is a very stiff plastic which is a good thing. The motors are from the same company I used for my BI-3600 inrunners for 70mm and they have a nice cooling hole through the motor. The outrunners are good for higher watts but these 50mm jets really only need about 300-350 watts to fly well and an inrunner should be OK, but that is what testing is for! If the inrunners are no good then I will work on a special adapter for the Wicked motor to hook up to this new fan unit. The inrunner solution will be the lowest cost, I was trying to avoid a special standoff adapter and rotor adapter which raises the cost of an outrunner solution.