EDF pusher Jet scratch build- contest 2
#26





#27









#28

How did you secure the DF to the tail? Doesn't look like there's enough surface area on that edge of Depron to hold it securely with glue. I have lots of DF parts lying around and was thinking of cobbling something together...probably won't look that nice though...I'm thinking of a kind of Rube Goldberg contraption...


Last edited by CHELLIE; 09-25-2008 at 05:44 AM.
#29

OK, what did I learn doing this build, First of all, My motor is much more powerful than i thought
I hooked up a wattmeter to it, and a powerful 3 cell lipo, and found out it is Drawing 500+ Watts at a little over 50 AMPS
WOW Thats about 3/4 HP if 746 Watts is One HP, OK, I was trying to epoxy a 35 size nitro motor to foam
thats about the same thing, It wont hold on for very long
OK, I am Learning
these Electric motors can be deceiving, in the amount of power they make
here is what i did to make it work this time, I epoxied 2 -3/8 x 3/8 basswood motor mounts to the foam, and will attach the EDF to that, they look like 40 size motor mounts
anyway, and i will screw the EDF to the wood mounts, I am making the Fuselage longer and a little wider below the wing, so a larger lipo can be used, Take care, Chellie









#30

That should hold up much better.
Hi Steve
I was surprised at the amount of power this EDF makes, the lipo I had is not very strong, and was only putting out about 30 amps and 300watts of power, I ordered a 2350mah 25C Rhino lipo from hobby city, so that should be about 58.75 amps and give about 500watts
BTW Steve, The Rhino lipo has a 37C lipo rating for 15 Seconds
86.95 AMPS, 800Watts Maybe
can we say SMOKING FOAMY
The EDF did not get hurt, Take care, Chellie
http://www.hobbycity.com/hobbycity/s...5C_Lipoly_Pack
I have a suggestion for a little better fan performance.
Take that section of the fuse just in front of the fan and cut it back a little further way from the blades and spinner - more towards the front of the plane. Also - taper down the square edge that faces the fan gradually down to a sharper point. That will help make the air entering the fan smoother and should increase efficiency.
Might give you and extra mph or two
Hi Steve





http://www.hobbycity.com/hobbycity/s...5C_Lipoly_Pack
I have a suggestion for a little better fan performance.
Take that section of the fuse just in front of the fan and cut it back a little further way from the blades and spinner - more towards the front of the plane. Also - taper down the square edge that faces the fan gradually down to a sharper point. That will help make the air entering the fan smoother and should increase efficiency.
Might give you and extra mph or two



#31

Well its all better now, I glued 2- 3/8x3/8 basswood motor mounts to the fuselage, and used 2 bands of plastic, that are glued on with sumo glue and epoxy, that EDF wont come off now, I Hope
I made the fuselage a little longer and wider at the bottom to fit a bigger lipo, and to regain my CG, from the weight of the motor mounts, I tried a 4 cell lipo in it, but it does not like a 4 cell
so I will stay with the 3 cell lipo, more test to come on it, Take care, Chellie




#32

Thank You Larry
The lipo I was using in the beginning, is weak, I found out, its new, but does not give the power that it should, its a 2250mah 3 cell 20C, with the watts up meter, it was only giving like 32 amps and about 300 Watts @ 9volts, and then dropped from there, its getting a Rhino lipo, Our club has been testing these Rhino lipos, and they are great, very very powerful lipos, and inexpensive too, I am going to use a 2350mah 3 cell 25C Rhino lipo with a 37C Burst so that should be 58.78 amps at 25C and 86.95 amps at 37C for 15 seconds
I think I should replace that 40Amp ESC in it
it should be a rocket with the new lipo
Take care, Chellie




#33

Chellie,
I am new to this forum. Just found it this week and set up to post.
I have the same ducted fan/motor combo that you are using on this jet. I also created a jet similar to yours and installed this EDF. Here is what I found:
1. On a 3S 1800 Polyquest battery I was pulling about 43 Amps. I quickly cut and then shaved off three blades from the fan. This reduced the amps by about 6. It then drew about 37 amps. The thrust did not significantly go down, but the rpm did go up. The end result was more speed and less amps. Since you already have more than a 1.3 to 1 power to weight ratio, you probably won't miss the thrust. It was very easy to shave the three blades off and still have a balanced rotor.
2. Even 37 amps used intermittently is still too much for a 30 amp esc. I cooked it in the middle of my third flight. I was just having too much fun doing large loops. Loosing motor power on a jet that is still tail heavy is not a good thing.
Try shaving off three blades if you like. Then you might feel more comfortable using your 40 amp esc.
Michael
I am new to this forum. Just found it this week and set up to post.
I have the same ducted fan/motor combo that you are using on this jet. I also created a jet similar to yours and installed this EDF. Here is what I found:
1. On a 3S 1800 Polyquest battery I was pulling about 43 Amps. I quickly cut and then shaved off three blades from the fan. This reduced the amps by about 6. It then drew about 37 amps. The thrust did not significantly go down, but the rpm did go up. The end result was more speed and less amps. Since you already have more than a 1.3 to 1 power to weight ratio, you probably won't miss the thrust. It was very easy to shave the three blades off and still have a balanced rotor.
2. Even 37 amps used intermittently is still too much for a 30 amp esc. I cooked it in the middle of my third flight. I was just having too much fun doing large loops. Loosing motor power on a jet that is still tail heavy is not a good thing.
Try shaving off three blades if you like. Then you might feel more comfortable using your 40 amp esc.
Michael




#34

Thank you for the complements
The Jet Flies good, but it would be better if the EDF was moved forward more, or maybe even a Mid wing EDF, reson being, to move the weight a little forwards more, its a little neutral Balanced, and will stall, if your not careful, so having more weight forwards, it will recover from a stall better, All in all, its fun to fly, just dont stall it
Take Care, Chellie


#35

Hi Chellie, I always enjoy your creativity and your forum.
I wanted to know if the EDF unit outfitted with a 5.3KV outrunner brushless motor is the same unit as the one I have.
I wanted to attach a pic but have forgotten how to in this forum. Long time since i join the forum.
The current drawn is very high I think over 40 amps on 3s 4200maH lipo.(I use bigger
capacity to test so that high current would not load the lower capacity lipo cell voltage down and give a false sense of reading.)
After a minute of test, the motor was very hot and smells too, so I stop the test.
If it is the same motor & EDF, think go easy on the throttle.
Best wishes
B5
I wanted to know if the EDF unit outfitted with a 5.3KV outrunner brushless motor is the same unit as the one I have.
I wanted to attach a pic but have forgotten how to in this forum. Long time since i join the forum.
The current drawn is very high I think over 40 amps on 3s 4200maH lipo.(I use bigger
capacity to test so that high current would not load the lower capacity lipo cell voltage down and give a false sense of reading.)
After a minute of test, the motor was very hot and smells too, so I stop the test.
If it is the same motor & EDF, think go easy on the throttle.
Best wishes
B5




#36

cool build.
I hadn't seen this thread before
Chellie.. if you are watching?
Are you still flying this little charm?
Do you have actual dimensions ?
Kinda like you had pictures of dimensions for the delta wing build.
I'd be interested?
Thanks
Dave in Naples,Florida
I hadn't seen this thread before

Chellie.. if you are watching?
Are you still flying this little charm?
Do you have actual dimensions ?
Kinda like you had pictures of dimensions for the delta wing build.
I'd be interested?

Thanks
Dave in Naples,Florida
#37

Hi Dave
i used the wing from my twin boom pusher jet, and made a 9mm fuselage for it, the EDF flies well, but it will fly better if the edf was mid mounted, reason being, it wont recover from a stall, to much weight at the rear, but a mid edf will not be a problem, here is the dimentions to the wing, and the fuse you can make to fit your edf, just use the TLAR method
That Looks About Right TLAR
Take care, Chellie
http://www.wattflyer.com/forums/show...124#post265124
Chellies Pusher Jet Plans
Hi Everyone
Well I Promised some Plans, Soooooo here they are,
These plans are the Limit of my High School Mechanical Drafting , Lets see, I graduated from High School about 3 years ago, so that makes me about 21 now, yes thats right ??
Well It Sure Sounded Good to Me
Here you Go, Have Fun, Chellie
Ps If using Foam Board, cut the slots in the booms and skid 3/16" rather than 1/4" for the 6mm depron
Attached Thumbnails



http://www.wattflyer.com/forums/show...124#post265124

Hi Everyone





Ps If using Foam Board, cut the slots in the booms and skid 3/16" rather than 1/4" for the 6mm depron
Attached Thumbnails
#39
Member
Join Date: Apr 2006
Posts: 550

Here are some motor specs,
great for all jet type foamies warbirds!!
BUY MORE TO ENJOY OUR 50% OFF DISCOUNT ON SHIPPING!!!
Ducted Fan Specification
<TABLE borderColor=#000000 cellSpacing=0 cellPadding=1 width=657 border=1><COLGROUP><COL width=133><COL width=517><TBODY><TR vAlign=top><TD width=133 bgColor=#00ff00 height=10>Dimensions
</TD><TD width=517 bgColor=#00ff00>62mm outer dia. x 71mm length (w/ motor)
</TD></TR><TR vAlign=top><TD width=133 bgColor=#00ff00 height=7>Shaft size
</TD><TD width=517 bgColor=#00ff00>3.175mm ( spinner adaptor type shaft)
</TD></TR><TR vAlign=top><TD width=133 bgColor=#00ff00 height=6>Weight
</TD><TD width=517 bgColor=#00ff00>71g ( with motor)
</TD></TR><TR vAlign=top><TD width=133 bgColor=#00ff00 height=5>Thrust
</TD><TD width=517 bgColor=#00ff00>680g / 1.5lbs ( flying weight)
</TD></TR></TBODY></TABLE>
Motor Specification
<TABLE borderColor=#000000 cellSpacing=0 cellPadding=1 width=545 border=1><COLGROUP><COL width=212><COL width=326><TBODY><TR vAlign=top><TD width=212 bgColor=#00ff00 height=10>Type
</TD><TD width=326 bgColor=#00ff00>2409H/7T
</TD></TR><TR vAlign=top><TD width=212 bgColor=#00ff00 height=7>Shaft size
</TD><TD width=326 bgColor=#00ff00>3.175mm
</TD></TR><TR vAlign=top><TD width=212 bgColor=#00ff00 height=6>KV
</TD><TD width=326 bgColor=#00ff00>5300kv
</TD></TR><TR vAlign=top><TD width=212 bgColor=#00ff00 height=6>Max drain current
</TD><TD width=326 bgColor=#00ff00>57A
</TD></TR><TR vAlign=top><TD width=212 bgColor=#00ff00 height=5>voltage
</TD><TD width=326 bgColor=#00ff00>11.1v ~ 14.8v(3s ~ 4s lipo
</TD></TR></TBODY></TABLE>
RC ducted fan combo unit
54mm 6-blades w/ 2409-7T brushless motor
RC ducted fan unit, 6 blades rotor with a high power brushless motor54mm 6-blades w/ 2409-7T brushless motor
great for all jet type foamies warbirds!!
BUY MORE TO ENJOY OUR 50% OFF DISCOUNT ON SHIPPING!!!
Ducted Fan Specification
<TABLE borderColor=#000000 cellSpacing=0 cellPadding=1 width=657 border=1><COLGROUP><COL width=133><COL width=517><TBODY><TR vAlign=top><TD width=133 bgColor=#00ff00 height=10>Dimensions
</TD><TD width=517 bgColor=#00ff00>62mm outer dia. x 71mm length (w/ motor)
</TD></TR><TR vAlign=top><TD width=133 bgColor=#00ff00 height=7>Shaft size
</TD><TD width=517 bgColor=#00ff00>3.175mm ( spinner adaptor type shaft)
</TD></TR><TR vAlign=top><TD width=133 bgColor=#00ff00 height=6>Weight
</TD><TD width=517 bgColor=#00ff00>71g ( with motor)
</TD></TR><TR vAlign=top><TD width=133 bgColor=#00ff00 height=5>Thrust
</TD><TD width=517 bgColor=#00ff00>680g / 1.5lbs ( flying weight)
</TD></TR></TBODY></TABLE>
Motor Specification
<TABLE borderColor=#000000 cellSpacing=0 cellPadding=1 width=545 border=1><COLGROUP><COL width=212><COL width=326><TBODY><TR vAlign=top><TD width=212 bgColor=#00ff00 height=10>Type
</TD><TD width=326 bgColor=#00ff00>2409H/7T
</TD></TR><TR vAlign=top><TD width=212 bgColor=#00ff00 height=7>Shaft size
</TD><TD width=326 bgColor=#00ff00>3.175mm
</TD></TR><TR vAlign=top><TD width=212 bgColor=#00ff00 height=6>KV
</TD><TD width=326 bgColor=#00ff00>5300kv
</TD></TR><TR vAlign=top><TD width=212 bgColor=#00ff00 height=6>Max drain current
</TD><TD width=326 bgColor=#00ff00>57A
</TD></TR><TR vAlign=top><TD width=212 bgColor=#00ff00 height=5>voltage
</TD><TD width=326 bgColor=#00ff00>11.1v ~ 14.8v(3s ~ 4s lipo
</TD></TR></TBODY></TABLE>
You probably could use in on a smaller ducted fan like the 70mmEDF but you will need 4S lipo for performance.
I have modified the motor so that it can fit into hoa ye 89mm EDF.
Runs around 36amps on 3S lipo. It spins the 89mm EDF at around 24,000 to 28000rpm.

Cheers
#40
Member
Join Date: Apr 2006
Posts: 550

Hi Chellie, here is a couple of picture of what I did with the mentioned motor.
The entire EDF +motor + bullet weighs a mere 154grams.
For a time being, this motor setup will run on 3S lipo.
More next time.

Cheers
The entire EDF +motor + bullet weighs a mere 154grams.
For a time being, this motor setup will run on 3S lipo.
More next time.

Cheers
#41


#42
Member
Join Date: Apr 2006
Posts: 550

Hi Chellie, test flight successfully, the 89-90mm EDF on a converted twin micro-jet .
Thrust is just 1:1 . The plane weights just over 1kg.
Runs on 4500mAH 3S packs peaks at 36amps at around 25000-29000rpm
This motor is 9pole and around 2.5Kv/V .
Plane is not very fast but quite fast.
Plan to upgrade the fan with a more powerful motor on 4S 400mah lipo.
More next time.
The blue colored plane in the back ground is the smallest version of micro-jet....all from multiplex.
Cheers
Thrust is just 1:1 . The plane weights just over 1kg.
Runs on 4500mAH 3S packs peaks at 36amps at around 25000-29000rpm
This motor is 9pole and around 2.5Kv/V .
Plane is not very fast but quite fast.
Plan to upgrade the fan with a more powerful motor on 4S 400mah lipo.
More next time.
The blue colored plane in the back ground is the smallest version of micro-jet....all from multiplex.
Cheers
#44
Member
Join Date: Apr 2006
Posts: 550

sorry, my previous post correct the statement...plan to run the edf on 4s on 4000maH ....400mah won't make it LOL


hi Alphea, the blue colored micro-jet are capable of over 100MPH with the correct pusher or EDF setup. Agree, the c.g is located at the bump but it is quite tricky to hand launch the plane with a pusher prop and mind those fingers during the launch.

Cheers



hi Alphea, the blue colored micro-jet are capable of over 100MPH with the correct pusher or EDF setup. Agree, the c.g is located at the bump but it is quite tricky to hand launch the plane with a pusher prop and mind those fingers during the launch.

Cheers
#45

Hi Chellie, test flight successfully, the 89-90mm EDF on a converted twin micro-jet .
Thrust is just 1:1 . The plane weights just over 1kg.
Runs on 4500mAH 3S packs peaks at 36amps at around 25000-29000rpm
This motor is 9pole and around 2.5Kv/V .
Plane is not very fast but quite fast.
Plan to upgrade the fan with a more powerful motor on 4S 400mah lipo.
More next time.
The blue colored plane in the back ground is the smallest version of micro-jet....all from multiplex.
Cheers
Thrust is just 1:1 . The plane weights just over 1kg.
Runs on 4500mAH 3S packs peaks at 36amps at around 25000-29000rpm
This motor is 9pole and around 2.5Kv/V .
Plane is not very fast but quite fast.
Plan to upgrade the fan with a more powerful motor on 4S 400mah lipo.
More next time.
The blue colored plane in the back ground is the smallest version of micro-jet....all from multiplex.
Cheers


#46

sorry, my previous post correct the statement...plan to run the edf on 4s on 4000maH ....400mah won't make it LOL


hi Alphea, the blue colored micro-jet are capable of over 100MPH with the correct pusher or EDF setup. Agree, the c.g is located at the bump but it is quite tricky to hand launch the plane with a pusher prop and mind those fingers during the launch.

Cheers



hi Alphea, the blue colored micro-jet are capable of over 100MPH with the correct pusher or EDF setup. Agree, the c.g is located at the bump but it is quite tricky to hand launch the plane with a pusher prop and mind those fingers during the launch.

Cheers

[media]http://www.youtube.com/watch?v=46nxgGaGj94[/media]
#47
Member
Join Date: Apr 2006
Posts: 550

Yes this particular micro-jet setup is just one crazy kilowatt hungry babe.
I think they juice the M-J to over a Kilowatt of power.
Next I am thinking of using your plane original plan for my next project but I will use corrugated plastic instead of depron foam with some modification to the wing to give it a suitable airfoil.
Corrugated plastic are more durable and take take in more abuse than depron foam.
Cheers
#48

Hi Cheelie
Yes this particular micro-jet setup is just one crazy kilowatt hungry babe.
I think they juice the M-J to over a Kilowatt of power.
Next I am thinking of using your plane original plan for my next project but I will use corrugated plastic instead of depron foam with some modification to the wing to give it a suitable airfoil.
Corrugated plastic are more durable and take take in more abuse than depron foam.
Cheers
Yes this particular micro-jet setup is just one crazy kilowatt hungry babe.
I think they juice the M-J to over a Kilowatt of power.
Next I am thinking of using your plane original plan for my next project but I will use corrugated plastic instead of depron foam with some modification to the wing to give it a suitable airfoil.
Corrugated plastic are more durable and take take in more abuse than depron foam.
Cheers


#49
Member
Join Date: Apr 2006
Posts: 550

Hi Chellie, long time no hear. I took some of your idea for the EDF tailess plane but use C.P. instead of Depron .
I built a proto-type with a flat wing shape and test glide and it seemed to glide pretty good.The glide test will approximate the c.g. position as well.
Next, I proceed cut out the actual CP material (2mm thick) and then bend and curve the CP material so as to give it a proper airfoil.
Attached are the various stages of the tailess EDF jet .
Many stiffener CP and ply added to the fuselage to yield reasonable rigidity.
The wing is 24 in span with the broadest width at 7in(without the aileron strip) and tapered 3inches width at the wing tip. This will give a pretty good aspect ratio.
The EDF will be a 55mm 6blade and will run between 16-18amps on 3 cells.

Cheers
I built a proto-type with a flat wing shape and test glide and it seemed to glide pretty good.The glide test will approximate the c.g. position as well.
Next, I proceed cut out the actual CP material (2mm thick) and then bend and curve the CP material so as to give it a proper airfoil.
Attached are the various stages of the tailess EDF jet .
Many stiffener CP and ply added to the fuselage to yield reasonable rigidity.
The wing is 24 in span with the broadest width at 7in(without the aileron strip) and tapered 3inches width at the wing tip. This will give a pretty good aspect ratio.
The EDF will be a 55mm 6blade and will run between 16-18amps on 3 cells.

Cheers
#50

Hi Chellie, long time no hear. I took some of your idea for the EDF tailess plane but use C.P. instead of Depron .
I built a proto-type with a flat wing shape and test glide and it seemed to glide pretty good.The glide test will approximate the c.g. position as well.
Next, I proceed cut out the actual CP material (2mm thick) and then bend and curve the CP material so as to give it a proper airfoil.
Attached are the various stages of the tailess EDF jet .
Many stiffener CP and ply added to the fuselage to yield reasonable rigidity.
The wing is 24 in span with the broadest width at 7in(without the aileron strip) and tapered 3inches width at the wing tip. This will give a pretty good aspect ratio.
The EDF will be a 55mm 6blade and will run between 16-18amps on 3 cells.

Cheers
I built a proto-type with a flat wing shape and test glide and it seemed to glide pretty good.The glide test will approximate the c.g. position as well.
Next, I proceed cut out the actual CP material (2mm thick) and then bend and curve the CP material so as to give it a proper airfoil.
Attached are the various stages of the tailess EDF jet .
Many stiffener CP and ply added to the fuselage to yield reasonable rigidity.
The wing is 24 in span with the broadest width at 7in(without the aileron strip) and tapered 3inches width at the wing tip. This will give a pretty good aspect ratio.
The EDF will be a 55mm 6blade and will run between 16-18amps on 3 cells.

Cheers

