3D-Foamy F18 EDF Mini Fan 480 Project
 

My quest for an inexpensive EDF plane has begun. I wanted something that looked cool, yet would not cost much. I also wanted something light that could be easily hand launched. I finished what I think are the hardest parts so the rest should go pretty quick now (at least that is what I keep telling myself). Just need to attach the wing, aeileron servos, rudder, elevator, finish canopy, sand and paint. Ok, maybe it won't be as quick as I'm hoping for... This is my first foam kit and first attempt at an EDF. I spent some time making a dual exhaust that is the correct size for the MF 480. I was going to make ducts for the intake but I'm getting impatient and may just leave it as is with the intake ring inside the semi-ducted stock layout. Original plan was not to use the intake ring and fully duct the intake up to the MF unit. The 3 turn Typhoon motor is putting out about 25 ounces of thrust with the existing setup when I cover the top so that it is only sucking in air from the intakes. Per MotoCalc I should get about 28oz. I question if fully ducting the intake will make enough of a difference on this plane to be worth spending the extra time on it? I am using a 4 cell LiPo pack. Let me know what you guys think. A lot of this is new to me so I hope I am on the right track.

RE: 3D-Foamy F18 EDF Mini Fan 480 Project
 

I think youre on to something there but I have a quick question regarding your stabilator pivot tube location. I looks a little aft to me[sm=confused.gif]. I have built 4 of the pusher versions is why I ask. Otherwise I think the tailcones look awsome!I am curious to see how it comes out. If you are at all concerned about wt. I suggest to forego the rudder. You will not need it if you fly it like a jet, Bank and Yank.[sm=bananahead.gif]

RE: 3D-Foamy F18 EDF Mini Fan 480 Project
 

Hi Vicman,

I am not putting in rudder control. I meant to say I had to install the vertical stabilizers. The pivot tubes are located in about the same location as called for in the plans. (It was a tighter squeeze than I anticipated to fit the servos between the exhaust.) However, she has a little bit of a fat rear end (in height) to accomodate the MF480. (Don't tell her I said that about her butt [X(] )About 18mm fatter than stock (added 3 sheets of 6mm Depon to the floor of the fuse for the extra room.) The tip of the exhaust tubes is about 3/4" longer than the standard fuse. Other than that the rest of the plane is made with the pre-cut parts. One of the sheets I extended all the way to the nose cone for extra strength and to give me more area to round out the fuse a little more when I sand it. Oh, I also cut off about an inch inside the fuse so that it would not be too close to the fan to create poor air flow. That does not change the overall length of the plane. Maybe optical illusion from photo on the pivot point?

Ignore the freeway photo, clicked on wrong one uploading.

RE: 3D-Foamy F18 EDF Mini Fan 480 Project
 

I placed the remaining loose pieces on the fuse with a little tape to hold em in place to get an idea what the finished thing will look like. Dang, work is a real pain. It gets in the way of my hobby. Time to go earn some money now...

Vicman, why 4? I hope 3 did not crash?!?

RE: 3D-Foamy F18 EDF Mini Fan 480 Project
 

Do you have a clear picture of the whole inlet system. This seems to the where most of the conversions fall short, the bit you have shown is better than the ones I have seen in the past. Good luck.

Eric B.

RE: 3D-Foamy F18 EDF Mini Fan 480 Project
 

No crashes. They were gifts:)I have worn the bottom out of mine and had to replace it from landing so many times. I plan on building another one for me in a few weeks. Too many other planes in the way and that work thing too:D I like what you have done and am anxious to hear how it does. I just got a Kamdax Mig yesterday, this will be my first suara' into the DF world.

RE: 3D-Foamy F18 EDF Mini Fan 480 Project
 

Hi Eric,

I can see that being the case. I thought I would just use the intake as is with the minor modifications I made to give a bit more clearance for the fan intake. With the top of the fuse off where it can suck in all the air it wants I recently measured 26.5 ounces (measured by exhaust blowing against a digital scale so maybe actually a little more?) Then I put the fuse and wing on and it dropped to 25 oz which I thought was an acceptable loss. Then I ran the wires from the two elevator servos and the brushless motor through the inlets into the center of the fuse. I also installed the two aileron servos that also protrude into the intake area. I tested it again after doing that and thrust fell to 19 oz! [X(][X(][X(]
So it looks like I will need to properly make some ducts for the intake that fully encompass the fan unit to avoid the turbulence the wires and servos apparently are now causing. Arggg! [sm=disappointed.gif] I thought I was just a short way from finishing this thing but that no longer appears to be the case.

Vicman, glad to hear you have not crashed them! I was getting worried for a moment. [sm=drowning.gif]

RE: 3D-Foamy F18 EDF Mini Fan 480 Project
 

Two elevator servos? I used only one attached to a CF rod connecting the two sides togeather.

RE: 3D-Foamy F18 EDF Mini Fan 480 Project
 

Exhaust tube is in the way to use the solid rod. I had to put a servo on each side or have a rod going through the exhaust which I thought would be bad for the air flow.

When will you have your Mig flying? I was thinking about that one or their Mirage kit a while ago but expensive.

I'm getting too impatient to build these things. At this point I'm thinking maybe I should have just gone with the HET F18. The HET seemed heavy so I was hoping to get something close to it in size and appearance but lighter (and less expensive) with the foamy kit. But the final weight of the foamy is going to be about 30-31 oz ready to fly including the 4 cell pack so I'm not sure how much weight I am saving. I wonder if the 30.5-37oz weight for the HET is the total fly weight with battery?

RE: 3D-Foamy F18 EDF Mini Fan 480 Project
 

PM;)

RE: 3D-Foamy F18 EDF Mini Fan 480 Project
 

Eric,
Here are the photos of intake, version b... Almost finished with the intakes now. Removed intake ring and made ducts. This should provide for clean air to the fan as air is no longer going around servos and wires.

RE: 3D-Foamy F18 EDF Mini Fan 480 Project
 

Hi Pilotsmith,

I think leaving the split clear plastic out would let you have better intake airlow to the fan because the thin edges will exclude a lot of airflow from the ducting. If you leave it in make sure to fair in the area arround the interface of plastic to the foam that will give you the best that you can do in this application.

Think about the outlet and how the thrust is reacting to the open area behind the aircraft, the air flow leaving the outlet react with only open air so the force the plane will see is only that reaction. Taking a thrust reading by focussing against a scale face is just changing the physics that are in force with real life applications, try pointing the nose down on the scale and letting the force of the airflow reacting to open air give you a correct reading because pointing the airflow to the scale face changes with the distance to the scale face which is a pressure change which is not present in real physical application.

I want to see you be succesful. Good luck.

Eric B.

RE: 3D-Foamy F18 EDF Mini Fan 480 Project
 

Hi Eric,

Thanks for info. The photos were not the finished product yet. I have shaped some glass cloth so that the clear intake tube blends into the foam further up just as you suggested. By what I have read, one should keep the volume of the intake ducts constant from start to fan and equal to the fan swept area. Without the plastic ducts the area is too large as you get closer to the fan which results in higher static thrust but not good dynamic thrust. (At least that is what the experts have told me.) I'll upload some photos tomorrow. Good point on the scale to point the nose at the scale. I have been told not to be concerned about static thrust as long as good ducts are installed. But I still like to measure what is happening just to see if something really seems off.

RE: 3D-Foamy F18 EDF Mini Fan 480 Project
 

It's almost ready to fly but I think I'm going to run out of time before having to leave on vacation. [:o] So here it is so far. To fly I only need to glue the elevators to the tubes and connect the aileron linkage. So less than 1 hour. Still need to do final sanding, filling, and paint. Ducts are ducted all the way through for smooth air flow. Hoping it will fly ok with the 3 turn brushless as most people go with 2 turn motors that suck up twice the amps. Will find out when I get back from vacation! :D The weight now is 21.5oz w/out battery. Now I have to decide if I go with Blue Angels color scheme or standard war colors...

RE: 3D-Foamy F18 EDF Mini Fan 480 Project
 

Had a setback as the paint I used ate up some of the sanded areas. Ready now for 2nd try at paint after replacing ailerons and filling in eaten up areas. Used Krylon Fusion paint for plastic and it eats foam unless put on real thin, specially on sanded parts.

RE: 3D-Foamy F18 EDF Mini Fan 480 Project
 

Finally finished! :D Ended up 23oz total weight without battery. Think it is about 1oz heavier than would have been had I not messed up the first paint job and had to use filler to repair damaged foam and repaint. Not sure if I will get a chance to fly before vacation. I'll let you all know how she does in the air.

RE: 3D-Foamy F18 EDF Mini Fan 480 Project
 

Looks Great!
Tinted canopy is a nice touch.

RE: 3D-Foamy F18 EDF Mini Fan 480 Project
 

Sorry about the time span between check ins just dont have time to check all the forums available.
You did a good job. Do you have a nose on the scale thrust measurement yet? I will check back this weekend to see if you responded.

Eric B.

RE: 3D-Foamy F18 EDF Mini Fan 480 Project
 

He is on vaca this week:D.

RE: 3D-Foamy F18 EDF Mini Fan 480 Project
 

I'd like to get started... quick question (never tried to assemble tiled plans off the home printer before) How do you line everything up?
I would like to gather the required equipment but the LHS seems to only stock and cater to the car and train people... :-(
HS-55 servos (out of stock)
CF spars (out of stock)
GWS fan units (out of stock)

Now I have to wait until that non-existent R/C budget replenishes because I couldn't pass up a 2500mah extended duration 8-cell NiMH pack for my 9caps and a charger for it. (should get 8+ hours out of it... beats the heck out of the 700mah unit it came with and only $5 more than buying an exact replacement...) And I finally picked up a real dremel variable speed tool (no-name knock-off burned up last year).

by the time I am finally ready there should be a few flyers with well-documented EDF conversions... I still haven't picked up the bundle of BlueCor from Lowes yet... I am seriously considering just ordering the pre-cut kit and going with the pusher setup... but I'd rather get fluent in the readily-available BlueCor and maybe that pink owens-corning stuff you can separate into thinner sheets...

RE: 3D-Foamy F18 EDF Mini Fan 480 Project
 

Go FFF with a eflite 370 and GWS C gear with GWS Naro servos and eflite 20A speed controller driven by a 11.1v 1500 mah Lipo. Regarding the tiled plans, make sure your printer is set to 100% for the size and simply print them out on 8.5X11 paper. Carefully cut the pages at the end of the lines and scotch tape them togeather. I used spray 77 and glued them to poster board and now have a sturdy set of templates to use for replacements, (on #5 currently).

Quit thinking and get building and flying!:)

RE: 3D-Foamy F18 EDF Mini Fan 480 Project
 

I'm back from vacation and torn between 2 weeks of work on my desk and a beautiful sunny day to maiden my 3D-Foamy F18 EDF conversion. [sm=sunsmiley.gif] A couple people have asked/emailed for more construction specifics, etc. Since I have no idea how this will fly, I'll wait until the maiden to post more details. If it turns out to be a dog there would be no point to post more details I would think. Hope to post some good news this week!

RE: 3D-Foamy F18 EDF Mini Fan 480 Project
 

I am going to be in San Jose on Sunday. How far apart is that? If your close enough I would like to buy you a drink and maybe watch the little hoover do its thing.:)

RE: 3D-Foamy F18 EDF Mini Fan 480 Project
 

Heck, that is just under 800 miles round trip from here. Now if I had the real thing I could fly it to San Jose for that drink in about half an hour!
:D

RE: 3D-Foamy F18 EDF Mini Fan 480 Project
 

looking forward to the flight report :-)