XF VIPER - Foamboard F-16 EDF
- Thread starter Mid7night
- Start date
That's a neat idea CJ ... but you may find that popsicle stick keeper could interfere with the battery placement. I was thinking of doing something similar, but putting the latch almost flush at the back of the canopy,
I'm also not convinced I like the way I have the canopy-plate (hatch) separate from that part of the forward/upper fuselage. It makes forming that part of the body a bit more difficult, and cutting the hatch out afterwards makes for SUCH a better closer and fit. Gonna have to think on that one some more.
Meanwhile, I didn't get to posting pics last night; sorry. I'll do my best to get those up today for you all.
P.S. @cjspecial: It's looking awesome!!
I'm also not convinced I like the way I have the canopy-plate (hatch) separate from that part of the forward/upper fuselage. It makes forming that part of the body a bit more difficult, and cutting the hatch out afterwards makes for SUCH a better closer and fit. Gonna have to think on that one some more.
Meanwhile, I didn't get to posting pics last night; sorry. I'll do my best to get those up today for you all.
P.S. @cjspecial: It's looking awesome!!
cjspecial
Member
@Mid7night No worries on posting the pics, life happens and this is a hobby, not a job, LOL. I agree on the popsicle stick possibly causing battery placement issues too, but I figured I would experiment anyway. I ended up cutting out a larger opening for the canopy access because I have big hands and I hope it makes accessing the components a bit easier without sacrificing strength. I'm planning on building a second or possibly a third one once I dial in the build process and component layout etc. I don't mind building multiple planes... I think I enjoy the building almost more than the flying! And thank you for the compliment! It's definitely been the most challenging build with DTFB yet for me and I'm enjoying the new skills that it's teaching, and it's my first EDF.
kilroy07
Legendary member
Here are my build pics in progress so far. I'll add build comments as I can go back and edit, but for now you at least get the pictures for reference.
One improvement I want to add are better fuselage-alignment features for the body pieces. It's difficult to keep everything straight with just your eye to go on.
Horizontal tail, elevator and rear strakes:
Double-bevel the leading edge of the horizontal, fold over flat. Single bevel the elevator hinge.
Glue strake-doubler on the bottom (not pictured yet). Crease/bend horizontal tail down relative to strake (not yet pictured)
Nose:
Center/Lower fuselage and intake:
Upper/Aft fuselage and EDF mount:
Lower/Aft fuselage and tail cones:
Wing:
The bamboo skewers are optional - I added them simply because it's a rather thin wing, and I tend to pull hard on the airplane.
ALSO: I show the wings folding over separately, then joining. It is better (if you have the space) to join the wing halves at the lower surface first, gluing down any spars and stiffeners, THEN fold them over.
ALSO NOTE: In the wing-folding pictures, you will see that I removed some paper, this is NOT NECESSARY. Your wing will be stronger (and not much heavier) if you LEAVE the paper and do a fold-over wing like normal. I just like the way the wing surface is a bit smoother when you remove some of the paper.
If you removed the paper as shown, DO NOT score the wing-folds in the upper surface. Still do the leading-edge double bevel, but don't do the score-cuts over the wing spars. The wing will curl over just fine.
Upper/Forward fuselage and nose assembly:
Inlet diverter and forward fuselage assembly:
Fuselage join:
ESC placement:
Upper fuselage cover:
One improvement I want to add are better fuselage-alignment features for the body pieces. It's difficult to keep everything straight with just your eye to go on.
Horizontal tail, elevator and rear strakes:
Double-bevel the leading edge of the horizontal, fold over flat. Single bevel the elevator hinge.
Glue strake-doubler on the bottom (not pictured yet). Crease/bend horizontal tail down relative to strake (not yet pictured)
Nose:
Center/Lower fuselage and intake:
Upper/Aft fuselage and EDF mount:
Lower/Aft fuselage and tail cones:
Wing:
The bamboo skewers are optional - I added them simply because it's a rather thin wing, and I tend to pull hard on the airplane.
ALSO: I show the wings folding over separately, then joining. It is better (if you have the space) to join the wing halves at the lower surface first, gluing down any spars and stiffeners, THEN fold them over.
ALSO NOTE: In the wing-folding pictures, you will see that I removed some paper, this is NOT NECESSARY. Your wing will be stronger (and not much heavier) if you LEAVE the paper and do a fold-over wing like normal. I just like the way the wing surface is a bit smoother when you remove some of the paper.
If you removed the paper as shown, DO NOT score the wing-folds in the upper surface. Still do the leading-edge double bevel, but don't do the score-cuts over the wing spars. The wing will curl over just fine.
Upper/Forward fuselage and nose assembly:
Inlet diverter and forward fuselage assembly:
Fuselage join:
ESC placement:
Upper fuselage cover:
Attachments
Last edited:
cjspecial
Member
@Mid7night Thank you for posting the pics! Those pics make all the difference and everyone should be able to have a successful build following them. I now see quite a few areas that I made mistakes on and will definitely be building a second one!
LOL .... NOPE! In fact, I'm quite embarrassed to admit that I didn't think of it myself. AND it would be easier to put in a spar member that spans the wing centerline by joining the wing halves BEFORE folding them over.
Truthfully, I think I've gotten into the habit of folding over the wings separately, THEN joining, simply because my build space is so limited. It's easier to manage half a wing and fold it over, than the whole wing.
You're welcome, and thank you for the compliment! Please take note of MY OWN mistake on the wing-build-process: Join the wing halves BEFORE folding them over!
cjspecial
Member
@Mid7night LOL, I did the exact same thing and I have a large work space! So I'm in the same boat...[/QUOTE]
cjspecial
Member
I must have been really tired when I was building last night. I completely missed the fact that I installed the rear section of the fuselage upside down! LOL Being that I made a few mistakes, with my new found knowledge I'm going to build another one 😁.
Attachments
Viper complete! Here are the rest of my build pics.
Horizontal tails and elevator (elevons).
The tails should have 10-15° of ANHEDRAL (angled down) relative to the side strakes and wing. Currently there isn't an angle-gauge, sorry, still need to add some little things.
Servos are glued on under the side strakes with short pushrods straight to the elevon surfaces.
The control surfaces are meant to be programmed as elevons, since there are no separate ailerons.
Control surface throws should be +/-20° to start, and I like at least 40% expo. You can push the throws up to as high as 30° or even 40° depending on how responsive you want the bird to be, and how confident you are on the sticks.
When balanced near the aft-CG mark, and flown with more aggressive throws, it will happily pull full-throttle Cobra maneuvers without breaking a sweat (or a wing).
Sorry, I forgot to take pics of the vertical tail and tail-base going together. The tail base glues on and wraps around the vertical tail, with a double-bevel in its leading edge.
Pics of the servo wires coming over the wing to the nose, the upper fuselage cover, vertical tail and ventral fins:
You'll want to feed the servo extension wires through the forward horizontal mount hole, connect the servo, and mount the horizontal tails making sure the side strakes are level and parallel to the ground.
After mounting the horizontals you can glue down the wing. It should slide all the way forward in the saddle, and the trailing edge should sit down flush with the bottom of the side strake.
Lastly glue on the ventral fins, and the vertical.
Done!
Horizontal tails and elevator (elevons).
The tails should have 10-15° of ANHEDRAL (angled down) relative to the side strakes and wing. Currently there isn't an angle-gauge, sorry, still need to add some little things.
Servos are glued on under the side strakes with short pushrods straight to the elevon surfaces.
The control surfaces are meant to be programmed as elevons, since there are no separate ailerons.
Control surface throws should be +/-20° to start, and I like at least 40% expo. You can push the throws up to as high as 30° or even 40° depending on how responsive you want the bird to be, and how confident you are on the sticks.
When balanced near the aft-CG mark, and flown with more aggressive throws, it will happily pull full-throttle Cobra maneuvers without breaking a sweat (or a wing).
Sorry, I forgot to take pics of the vertical tail and tail-base going together. The tail base glues on and wraps around the vertical tail, with a double-bevel in its leading edge.
Pics of the servo wires coming over the wing to the nose, the upper fuselage cover, vertical tail and ventral fins:
You'll want to feed the servo extension wires through the forward horizontal mount hole, connect the servo, and mount the horizontal tails making sure the side strakes are level and parallel to the ground.
After mounting the horizontals you can glue down the wing. It should slide all the way forward in the saddle, and the trailing edge should sit down flush with the bottom of the side strake.
Lastly glue on the ventral fins, and the vertical.
Done!
nevenelestate
No Agenda FPV
Mid7night, good looking build, now you need wing tip pylons, they aren't an option on the real plane
Chuppster
Well-known member
On the photo with the two wing halves and triangle, is the triangle part of the wings? Or are they just like your A-4?
The triangle piece, while not part of the plans, IS a piece I inserted as a joiner-helper, mostly to keep the skin between the spars from sagging when pressed on.
ALSO NOTE: In the wing-folding pictures, you will see that I removed some paper, this is NOT NECESSARY. Your wing will be stronger (and not much heavier) if you LEAVE the paper and do a fold-over wing like normal. I just like the way the wing surface is a bit smoother when you remove some of the paper.
If you removed the paper as shown, DO NOT score the wing-folds in the upper surface. Still do the leading-edge double bevel, but don't do the score-cuts over the wing spars. The wing will curl over just fine.
cjspecial
Member
I was thinking about designing some and 3D printing them along with some of the missiles and fuel tanks. When I get them finished I'll post up the STL files.Mid7night, good looking build, now you need wing tip pylons, they aren't an option on the real plane
cjspecial
Member
@Mid7night I'm having a bit of a challenge on the placement of the forms. Specifically the under canopy form. Should I make two forms and place one towards the nose and the other towards the rear portion?
mrjdstewart
Legendary member
thanks for posting the pics of the build. with all i have had going on, it's hard to remember all details. this is still on the short list but the Red Bull Challenge has been killin' me. a whole new respect for you guys and the effort and time it take to produce a model. the amount of info i have learned over the last 2 months has been unspeakable.
laters,
me
laters,
me
william steendam
New member
any idea how well this would fly if I reduced the plans to % 71 and put a 50 mm 12 blade edf on her ? its what I have lying round at the moment, also would this affect cg ? cheers
kilroy07
Legendary member
@Namactual posted some awesome rails for his Dat Rhino Not sure about scale as yet as I have JUST cut parts for my copy but they look great printed!
https://forum.flitetest.com/index.php?threads/dat-rhino.36276/page-10
![IMG_7284[1].JPG](https://ftforumx2.s3.amazonaws.com/2018/08/190134_f691bb9d35f97d9e8e2d7ae131348728.jpg "IMG_7284[1].JPG")
