Recent Attachments for Hepdog
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Nut and AS putting on a fine formation show. Come to think of it, Nut put on a mini-airshow by himself - the man is a flying machine! Thanks buddy.
Nut needs to relax a little more...;)
Post maiden congrats.
Short final to a greaser.
Sorry, can't recall who's plane but the detailing and sound system!!! VERY nice - Definite AITH top dog type stuff. Glad to get to see and hear it fly.
Check out how the rudder splits on the elevator
Against a Lancaster
Motor tilt mechanism. Nothing fancy. On elevator channel. Neutral is about 10 degrees forward. Full back (up) on stick give a slight rearward movement. Full forward is full forward!
Standard S76 servo on tail using stock hardware. One ply adapter and longer arm is all that is required
Quick and dirty belly gear. Will purty it up a bit later.
RCified shark! Need a bigger room to fly in - golf dome this Friday should do!
Ugly but will it fly?
Belly is fairly clean. Motor housings are still too big for this scale - might have to build V3 a little bigger - foam weighs next to nothing anyway...
Open cell foam can only be made so smooth without a substantial weight penalty - good enough!
Ready to fly. Hatch on top is for battery and electronic access. I wanted it on the belly but this thing is soo small
Obligatory test fitting - not long now....
Some spackling to make it all smooth - using "wonderfill" and it sands well, doesn't shrink and weighs nothing!
Little peice of lite ply should make for a secure motor mount.
Those rings are the template for the pods. Slit in top allows cutting both ID and OD shapes.
Still have to sand in the curve shape and do a bit of filling - but this seems doable.
Voila! Hollow foam tube that the itty bitty EDF's just slid right into.
Tack the templates to a square block of foam
2 wood rings are my hot-wire templates - I will be cutting out the inside as well.
work so far - now to strip the gear off the chucky and start putting in the new one. No more test flights once that is started.....
Weighing parts is always important - 49 grams is actually 10 grams lighter than the chucky!!!! I never paint anything until I know it flys but mini-airliner tails are so fragile best to paint before assembly.
Each wing just plugs into the fuse. This also allows me to bend the AL tubes to get some dihedral - want this to be a stable lazy flyer - just like an airliner.
One the curve is set I added the KF bottom part (also curved). Then I added some Aluminum tube to make the wings removable/replaceable. Where I fly we tend to shred wings off - there are 2 wires hanging down in the middle of our indoor space that eat wi
Undercamber should help this model fly slower - which is what I want. SLOWLY and carefully add your curve by rolling on a soft edge. Make sure each wing is the same.
I always cut out the important bits before getting too far along. If you do this right the left cut can be used on the right wing.
Fuse blocks sanded to about the right shape - will fine tune as the build progresses. Wings are cut from "Cellfoam" but could also be Depron or even blue-core - whatever works and is handy. You see 2 wings - I like to use KF wings
A little sanding cleanup and the open cell foam starts to look about right. Rough sand the tail and nose shape and I then take a Dremel (and a vacuum) and hog out the inside a bit. Saved an ounce of foam doing this.....every little bit matters on micros
Didn't think to take pics of the rough cut foam but here are the templates. Drawn on paper first, then transfered to wood and that is spot hot glued to the foam blocks on each end. Run that through the hot wire and we get rough cut round foam plugs
Test flying time - up here in the frozen North an indoor hockey arena is mighty nice - even at -5C. Didn't fly well first try - CofG was too far aft, trim was all wrong, throws were way too much - BUT the size was perfect for those EDF's!
This is my hot wire set up. To make a full fuse I could have used rolled depron but I like to use solid foam blocks and sand to shape. I save the foam packaging blocks from all our purchases - TV's, furniture etc - comes in handy for smaller builds
Decided to add gear to the chucky - why not?!?! I don't waste time making things purty till I know the idea might actually work - at this point I had no idea if those little EDF's would power such a large model or be too much etc etc etc.
My plans! See the "X5" top right? I take measurements off the 3-view and multipy by 5 and draw that on the foam etc. X5 just happens to be the size I want this plane - could be X25!
Once it's gliding right balance it and mark that spot! That should be the CofG for the flying powered model - note key word is should - bit of tweaking might be required.
Step 1 in a scratchbuild should always be a simple "chucky". Ugly but effective. See the weight taped on the nose - that was added and moved around to get the CofG right by throwing it - chucking it - until if flys right....ish.
V2 underway. Fuse is hot-wired from blocks of foam saved from packaging and wings are Cell-foam. Airframe weight should be around 50 grams.
Fan-fold, protection board, blu-cor - this is it! Bought this block about 4 years ago for $30 and still have lots left - great stuff.
See the velcro behind the batts - that is where I started out and it didn't fly. Move the batts up 1" and its flyable but still needs a little more nose weight.
CofG of the unladen chucky was the blue lines - way to far back to fly under power. Black lines are pretty good - flys alright but a touch sensitive. Will move it forward another 1/8" and try again (charging batts)
When its -24C outside the relative warmth of a -5C hockey rink makes test flights much more civil.
Underside. Note how all the gear is pretty much in the middle of the fuse. Just worked out that way to keep the CofG where it needed to be. Threw this in the shop once and it still glides nice and flat - just faster.
Ugly but should fly. Its just a test plane to see if the size is right for the power set up.
Here is my CofG finder - two skewers to balance the plane on upside down. Wherever it balances level - THAT is the CofG! Mark it with a marker! As I go on and add gear I check to make sure I'm still balancing on that CofG.
My simple chucky 737. Notice the weight taped on the side - this resulted in a perfect flat glide tossing it in the shop. That means I have found the CofG for this setup.
Avro Arrow built from F86 guts
This was the hard part - doing some aerodynamic research on the wind velocity of a feather vs. MAC. I wouldn't want you guys to think I was slacking off at night! Got some good numbers (it was a holiday - don't judge me! LOL)
Prizes! And a certain sticker better be there when I come back.
2 T-Birds in loose formation!
Gettin down low!
Only thing missing is the black exhaust.
Tell me that doesn't look real and I'll buy the next beer.....
Amazing work with flite metal
Humbled to be here.
Calm day lets little guys fly - maybe need to work on landings
Blue on blue
2 Wildcats in formation - the Nevada sky is SO blue!
THANKS Justwingit - broken wing and all - dang good group - just like home!
Racer over the mountains.
Big n small.... or FOD potential!
Glamour shot! We loved the A4!
Warm and happy!
Love the flight line
RCGroups lets us all follow along during a build's trials and tribulations. My Daughter (who is also a budding RC pilot) followed this one many a cold night in the shop.
The devil is always in the details - beautiful details..
Meeting the RCGroups gang for the first time in person....so confusing real names vs. handles LOL...J is easy to remember LOL
There was grass for belly landings.....
2 BIG Buffs - beautiful.
Nut and J post flight
Greased it on
Sweet low downwind pass
That would be a real thermo-nuclear bomb she could carry - De-activated of course
She is in rough shape right now but they are planning a full restoration.
Where is everyone?
a solid 4" of stroke gives more options to move the battery tray.
If you look close you can see the barn door sized rudder. It proved very effective and required on the test bed.
ET is 5' long - SRB's will extend past that to equal 6' in total.
Front view - bottom is like a V-hull on a boat - top will be a full dome structure to replicate the ET
On her own legs for the first time
Front framework starting to come together. Hard to visualize but this is like a boat - upside down.......it will make sense later......maybe!
Two tubes (one cut in half) go over those holes and vent the ejection charge rearward. It all gets a layer of FG to either make it strong or turn it into a pipe type bomb - I will test beforehand - with video of course!
Rocket motor pod. Holes in the top are to vent the ejection charge...hopefully. Been a while since I played with rocket motors....
Bottom view. The CF rod connects the ET to the SRB's and allows them to be removed for service etc.
This is the lower front section (upside down of course). I like the look of a balsa skeleton but its soo much slower than building with foam. Gear mounts are top rear.
How to bend balsa - soak it in water or ammonia water mix. Gently bend around a metal drum of the appropriate radius. Clamp in place and...
Put a heater on it. When dry it holds the curve perfectly. Only takes about 2 hours start to finish and exact parts are repeatable.
A battery box is attached to the sliding rail and has to pass through all the framework. This probably makes no sense right now - but will once I frame it up some more.
Retracted everything is nice and tight - easy to hide or fair in the lower tank structure. All wood you see is only a mock-up.
The final solution was a drag link and the shock towers mounted way out on the edges of the tank. This puts all landing loads on the strongest part of the structure and no loads on the tiny retracts at all.
Next was figuring out the third link and how everything tied together. Originally I was going to use a trailing link but it proved too onerous and flexible.
The cam at the top was needed to keep the wheel geometry in a straight line when retracting. This took a while to figure out - no CAD in my shop!
I used super small E-flite air retracts cause they weigh in at under 2 oz total and they were pretty powerful.
Retracted side view. There will be a servo actuated lock mechanism to hold it in place as vertical acceleration might be too much for the servo alone to fight - even with a slight over center actuation.
Extended top view
Scissors in the retracted position will move the pack all the way up front.
Scissors in the extended position gives alot of movement possibilities.
Total length of ET is 5.5'. There is another 6" of SRB tailend behind the Shuttle yet to be built.
....a few sets of "broken" electric retract guts got me thinking how to use the parts - stay tuned for if this works????
This contraption is my first thoughts on moving the batt box the required 12-16" needed. 3 GWS gearboxes mated up to produce a LOT of torque. BUT it's finicky and I think I have a better idea....
A gyro! It also works with elevons - critical to this application! It goes in a trusty 3D foamy first to see how it works.
3 hours later a 6oz rocket?
Contents of the bag
15 bucks worth of EPP
Post flight - still in one piece. Picnic table is 6' long.
Beyond that fence is a test flight - gulp!
Image stolen from the foamies thread...
Yes it's dark and yes that's ice and snow. It was also sorta windy and snowing a little...just wanted to do some taxi tests but ended up doing test hops
Outside and ready to fly.
2 balsa bits glued together - one with a hole - make for a strong mount.
The CF rod from each motor pod needs to tie into the top wing
The heat shrink is looped around a CF rod glued to the wing - again plenty strong.
The 2 main cabane struts tie deep inside the fuse to the wing saddle and balsa. Proved very strong.
Just waiting for paint - which is waiting for the motor pods to be finished.
Final gear set up. Might buy one sized bigger wheels but overall happy with the size.
Fuse looks not bad. Gonna half to make those motor pods look much better.
Just tacked together so I could make airplane noises.
New bottom wing. Cleaner and much much stronger. No ugly wires either. Sure hope I hooked them all up right.....
Solution was to add another CF spar and balsa doubler to add a bottom skin. Not much weight gain but definitely required.
Perched on her new legs for the first time - just a test fit. Result - that bottom wing is WAY to floppy!!!
Some minor length differences to trim up a bit
assembled on wax paper over a drawn template ensures they are almost identical
4 layers of 1/32 ply clamped together to make the gear assemblies. This is an easy way to make all cuts the same.
The servo arms sorta look like the real control wire arms....sorta.
These are the CF control rod stiffeners - 2 on each rod. Used hollow plastic tube glued to CF struts - some string and CA to make it strong.
Added the side markings - kinda neat.
Ready to rock and roll
I'll probably cover this with a sheet of thin depron just to make it look cleaner
Starting all the motor wiring etc
Both pods glued on.
I leave the top of the pods open until I'm done fitting all the bits - just in case. I'll make it look like something later.
Lots of test fitting to get it all square and getting the wing saddle curve right - it's mostly a glue joint that holds is on.
Hole in the center to keep the back bearing from binding
Test fit and center the motor and mark the screw holes
Lines on the ply motor mount to keep things squared up.
Motor pod parts. 3" tall by 1.2" wide and about 1/2" longer than the wing chord. Same basic build technique as the fuse.
Cut the first motor pod down and am satisfied it looks about right...
Simple way to make angled struts - heat shrink tubing! Glue it on with regular CA and then shrink it - very strong. This is the cabane strut and the bottom gets glued deep into the fuse. The top loops around a CF rod in the wing.
Found time to spray the fuse - no markings yet - not until it flys will I put that much time in.
Test assembly. Not bad I guess. Still not sure about those motor pylons...have to sleep on it.
Circles and lines
...for the crew member openings. I haven't decided which ones will be open or just painted - for sure the front gunner will be open - that's where the batt goes in!
I'm using Electrifly 5 gr servos - work pretty good. The white screwdriver is making center hole markers on each compartment...
This thing looks naturally tail heavy so the servo's are going as far forward as possible. I will also run the control rods on the outside - sort of a scale look...
Nose is bent down to look right. Cut off the excess and sand smooth. No particular measurement here - whatever LAR!
Trim out the excess balsa to match the wing saddle.
Balsa glued in. Note the 3/13" square sticks added in front of the formers - should keep it from cracking so easily.
Adding some balsa reinforcement inside the fuse. This is a common breakage area - I build to fly but also for the occasional rough landing. I may add some lite ply here later...
Note the added fuse "panel lines" - add those before cutting out the fuse! Anyway this is test fitting the lower wing to the fuse - align both the saddle and ensure its square.
CF strip ties into the rear fuse - should take a few bumps without breaking off.
Elevator glued in. Adding a CF vertical to the vertical fin - they tend to break off if just foam.
Test fit - see the slot for the elevator half.
This is the gap in the fuse sides the vertical fits into - you need to decide on this width when cutting the fuse - in my case 6mm (hence 3 - 2mm parts on the vertical)
Tail feathers all ready to assemble
Same idea for the rudder (which might be a tough small??) The vertical fin is 4" tall - should be 5" (half elevator span) but again LAR...
Lay it flat and press down the tape. Done.
Lift the elevator into the tape at your max deflection angle. This ensures the right gap for control movement.
Strip of hinge tape laid all the way across. I keep it on the edge of the table so it doesn't stick to the table or pick up dirt etc
Test fit - next is hinging
Ever have the elevator halves break? I use a 2mm CF rod to help avoid that. Use wax paper so you don't glue it to the workbench! Simple glue job and it's lined up everytime.
Forgot to add rib lines so back in the cut out to keep them square.
Test fit. The horizontal and vertical have half-notches for alignment. All 2mm depron
Horizontal is 10" wide by 5" deep. LAR...
beginning the tail feathers. This is the vertical. 2 laminations of 2mm on each side to fit in the fuse
Formers glued to the top first - nice and square. Then each side is drawn in and glued up.
Inside formers out of 3mm depron - actually needed 4 which you'll see later. Measurements are whatever your fuse makes - rolled fuses change a bit depending on technique
Carefully fold until it almost holds shape.
Use an strong straight edge to make a crease on the fold line - I use a steel ruler
Tape on the good side to keep the foam from cracking
Cut out and ready to fold and assemble
I just guessed on the fuse taper - LAR? I kept the top flat so the tail is easier to get 0-0 with the wing
Same 2mm sheets aligned for natural bending. Simply draw the fuse right on the foam (inside of the fuse). It's 24" long, 2.5" tall and wide. Include the wing cutouts starting at 14" from the tail
maybe too tall and too wide...have to sleep on it
Square - sitting on it's own!
Looks about right
doublers ready to accept struts
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