The scratch-built twin-EDF CH-F14
- Thread starter Chuppster
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- 64mm edf edf f-14 scratch build
Chuppster
Well-known member
I have a knob on my transmitter, but for now I plan to use the 3-position switch, so they will jolt.
Yeah, this piece is the "spar." I hope they servo will hold up. If not I may have to get really creative and do a DIY linear actuator. I'm trying to shy away from this so that other can repeat my design more easily.
Thanks for following along!
Looking good!!
For a reliable, low cost high torque servo, I HIGHLY recommend these:
https://alofthobbies.com/power-hd-1501mg-metal-gear-servo-15-5-kg-215-oz-in-16-sec.html
For a reliable, low cost high torque servo, I HIGHLY recommend these:
https://alofthobbies.com/power-hd-1501mg-metal-gear-servo-15-5-kg-215-oz-in-16-sec.html
Chuppster
Well-known member
Thanks!
Right now the control horn flexes, so right now I think the limitation is the plastic control horn.
Look at what @Mid7night did with the F4 for the canopy - this should get you to where you want to go.
DamoRC
DamoRC
kilroy07
Legendary member
So, just saw this thread, I'm really impressed with your work so far!
Going back to your request for equipment suggestions, I have my own twin EDF build I am planning on starting soon... You know as soon as I get a "free" weekend or three! (Shush, don't tell my better half.) Anyway enough of that nonsense;
Here's what I found over at Grayson Hobbies;
http://graysonhobby.com/detrum-factory-assembled-64mm-edf-motor-fan-unit-w-blades.html
I bought two and they seem to be high quality (and are on sale right now for $19 each!)
Only 6 blade, so sound might not be as cool as a 12, but (as I understand it) 6 blades are usually more efficient?
(This is my first foray into EDFs so if I'm way off here, someone please correct me.)
Going back to your request for equipment suggestions, I have my own twin EDF build I am planning on starting soon... You know as soon as I get a "free" weekend or three! (Shush, don't tell my better half.) Anyway enough of that nonsense;
Here's what I found over at Grayson Hobbies;
http://graysonhobby.com/detrum-factory-assembled-64mm-edf-motor-fan-unit-w-blades.html
I bought two and they seem to be high quality (and are on sale right now for $19 each!)
Only 6 blade, so sound might not be as cool as a 12, but (as I understand it) 6 blades are usually more efficient?
(This is my first foray into EDFs so if I'm way off here, someone please correct me.)
Namactual
Elite member
@kilroy07
I ordered two of those exact fans from Grayson about 2-3 years ago. Both of mine came with a 4100kv motor rather than the 4400kv stated. Static thrust was 560grams @ 32amps on 3s. I did not do a 4s test as a 4s battery would not fit my airframe at the time. Sadly, I paid A LOT more for mine back then.
@Chuppster
You really do not need to do curves. Once in the air all you are going to see is the outline or profile. A simple extruded profile canopy would work. What I like to do is start with a simple extruded profile, then slim the extrusion faces on the top, front and back while leaving the bottom middle area full width. This way a few number of flat faces gives the profile needed from most angles. I can draw up some quick examples if you are interested.
I ordered two of those exact fans from Grayson about 2-3 years ago. Both of mine came with a 4100kv motor rather than the 4400kv stated. Static thrust was 560grams @ 32amps on 3s. I did not do a 4s test as a 4s battery would not fit my airframe at the time. Sadly, I paid A LOT more for mine back then.
@Chuppster
You really do not need to do curves. Once in the air all you are going to see is the outline or profile. A simple extruded profile canopy would work. What I like to do is start with a simple extruded profile, then slim the extrusion faces on the top, front and back while leaving the bottom middle area full width. This way a few number of flat faces gives the profile needed from most angles. I can draw up some quick examples if you are interested.
kilroy07
Legendary member
Huh, I had to go check but mine TOO! (4100s) In their video review I think they said 3S was the max you should run anyway.
I haven't got around to spinning mine up yet ('cause you know... Projects...) How did they work out for you?
1120g huh... I am wondering now if that will be enough for my project...
Chuppster
Well-known member
I might just have to steal from Mr. Ben.
I was hoping to get something 4s. @Namactual is making it sound like they don't have a ton of pull, what do you think?
I appreciate the offer! I think I'll try scaling @Mid7night's design and see if that work. Otherwise I may take you up on that! However, I do want a bird that looks good in the sky and on the ground.
Thank you for the pointers on the EDF's!
Namactual
Elite member
@kilroy07
Aye, they recommend 3s. They did work for my particular application, but they were only a 60gram increase in thrust over the factory unit I had installed before. It did help with hand launches, but not worth what I paid for them. Not even close.
@Chuppster
The fan you linked in your OP looks like a monster. 60-70 amps according to the reviews. Thats a lot of watts. Make sure your battery is rated for that kind of amperage. With a 3000mAh battery, make sure it is rated for 50c at the very least to push two of those fans.
Aye, they recommend 3s. They did work for my particular application, but they were only a 60gram increase in thrust over the factory unit I had installed before. It did help with hand launches, but not worth what I paid for them. Not even close.
@Chuppster
The fan you linked in your OP looks like a monster. 60-70 amps according to the reviews. Thats a lot of watts. Make sure your battery is rated for that kind of amperage. With a 3000mAh battery, make sure it is rated for 50c at the very least to push two of those fans.
Chuppster
Well-known member
Namactual
Elite member
You could always do two smaller quad batteries if you have any just to get it trimmed out and air worthy. That is easier to do with a lighter weight. 2 x 1550 @75c would give you a minute or so and might be lighter than the 6000mAh.
With the numbers those fans are pushing though, I am not sure you will need to bother.
With the numbers those fans are pushing though, I am not sure you will need to bother.
Chuppster
Well-known member
With the numbers those fans are pushing though, I am not sure you will need to bother.
That's my hope. Also, flight time over a minute would be good!
I may just get two of the cheaper, 30 amp fans. They claim 750g a piece. Or I could get one of each...
Chuppster
Well-known member
Update:
I glued the wings on and added fins. I think we are about ready for a glide test! Just need to get linkage installed for the control surfaces.
Rudders will be an option (with only one servo!), but I don't think I'll use them for the alpha build.
I think it looks really good so far! I am concerned that I'm going to have to switch to two servos for the wings. This single servo can't move the wings very well.
I glued the wings on and added fins. I think we are about ready for a glide test! Just need to get linkage installed for the control surfaces.
Rudders will be an option (with only one servo!), but I don't think I'll use them for the alpha build.
I think it looks really good so far! I am concerned that I'm going to have to switch to two servos for the wings. This single servo can't move the wings very well.
