Welcome to my build log of the new JePe FastFoam A-10 which is an extreme makeover of the LX-A10 kit with many JePe improvements in construction / Fan units / Retracts and Aerodynamics. With all respect to the original painted RTF-version this Jets now has become a high performance JePe FastFoam Jet. When 2 companies have spend so much time in this ‘2-stage design project’ than you can expect a very special kit.
Now on stock and ready to ship!
scale detail still good visible after glassing with PU-EPS and 25 gramm glass tisseu. (Picture is of glassed wing that has even had a second coat of PU: ready for paint job!) Because this model is so complex I advise to use only PU-EPS finish(not endless Epoxy mixing all the time..). PU-EPS Finish will save you really much time and weight on all these parts.Kit with Pilot /decals/ rockets/bombs all in white EPS foam which is perfect for glassing! Modifications are already done in the JePe Atelier for you: below you see lowered angle of attack for mainwing (less drag / better inverted flight/ better speed)foam already removed by JePe so your wing will fit easy to new lifting angle
the non scale “box shape” wheel fairings will be reduced for the 4 kg landing gear version by JePe into more scale wheel fairings were half wheels stick out (just like the real one). Also larger scale size wheels of 70mm are now possible(good for improved grass runway take-off). If you order the standard plastic LX landing gear with this kit than I will leave it like it is so original landing gear will fit the wheel bays.
A-10 material List of parts needed to finish a Jet like this:
- PU-EPS glassing material with 3,3 m2 25 gr Glass
- 6x digital metalgear mini 14gr Corona DS-929MG servo
- 2x micro 6 gr servo (rudders)
- 1x analog metalgear servo 14 gr Corona 929MG analog (nosegear steering)
- 2x30cm servo extension leads for flaps
- 2x30cm servo extensions for the main retracts
- 2x45cm servo extension leads ailerons
- 2x Y-Cable 30cm for elevators and rudders
- 2x 30cm servo extension leads for elevator and rudder function
- 3x Suspension Leg ‘Off-set’ version 108mm long
- 2x 70mm and 1x60mm light Foam Wheels drilled for 4mm shaft
- 4kg version stronger retract mechanic set (best change the standard plastic LX retracts for a set of JePe cnc strong mounting plates to hold the stronger 4kg retract system)
- 1x JePe A-10 retract mounting plate set for 4 kg mechanics (you can switch these for the LX Plastic retracts)
- 2x70mm JePe Jet70-6s 7-blade (can run on just 5s pack(s)) or light outrunner Fans
- 2x80Amp cotroller (2x YEP-80 Amps 6s on my prototype)
Let’s start with building! Fuselage:
Glue all extra cnc 4mm Plywood parts into place, best with PU-Glue (use some needles and scotchtape)part most on left is thicker 5mm balsawood some parts are doubled because of hight differences in Foam
Time to Glue both rear fuselage half together with only little PU-Glue and tape it together with some Scotchtape and needles for best possible join. Do NOT glue nose section to fuselage yet!(comes later)
the wing lift angle correction made from 4 cnc balsa formers (each 5mm thick) there are 4 of these cnc corrections (2 glued next to each other)Glue this plywood front bulhead into place and than mark the holes onto your wingpanel (I used a drill to mark the positions of holes)drill 2 holes in wing and glue the 2 pins in place with some fast Epoxy , put wing in positions during hardening so the pins line-up with the holes in the plywood bulkhead (I used some PU later on to fill the holes around the pins a little but not do this as wing is still in position: the PU will expand and you can not remove your wing anymore..shit!)Next step is to bring the plywood battery extension tray into place with PU-Glue and glue also the nose onfrom below you see other end of the battery tray glued strong to the bulkhead that will hold the 2 carbon wing pins
take out the rear plastic wing bolts holdersuse your sander to shorten the topsideUse your dremel tool to fit the holes for the bigger Plywood washers and use some Epoxy to push the parts back in place. 2 longer M3x60mm Bolts are in the extra parts kit (these longer bolts make it easier to put your model together on the flying field)
building the main Wing:
first we need a cutting line to remove some foamat wingtip you must cut-off full 15mm (like the balsawood 15mm trailing edge)at middle were the 2 wingpanels meet it is only half of this 15mm (half of balsa trailing edge)use some help to make the cut under 90 degree of the centre line of wingprofile
you can see: more foam removed at wingtip than from middle of wingagain some Scotch tape and needles to keep things in place (keep nice in line with centreline of wing profile)trimming the middle panel: cut again half from the 15mm wide trailing edgeafterwards you can do sanding with a block and some 150 grain sanding paper some Easy-Foam Filler and a blade of a knife to make it perfect smoothnow we cut the wheel fairing complete off !! use a fresh blade don’t be so shocked: “its only a TOY “
Joining the wing panels:
first you do light sanding of the contact surface between the wing panels so your glue can do good bonding. Use some Scotchtape annd needles to keep the wingpanel in position. Inside is a alluminium tube connection from the standard kit: check this tube on right angle (6cm from picture further below). You can sand the tubes from the outside and glue them with some PU-Glue
than you level out the main wing panel on a table, use same hight of spacers under the wing so it is 100% level with the table.
both Wingtips must rise 6cm (scale!) no not Inches! let it rest like thisNext day you can put in the Epoxy Rudderhorns that are drilled for 1,7mm these fit perfect for Kwiklink steering (use Epoxy to glue these in place)
main Landing gear Plywood mounting for optional 4 kg retracts:
clear this pocket so the plywood part fits in nice
use Dremel to deepen the pocket. Go deeper untill you hit the aluminium tubingthan you make 2 sleeves so you can put in the 11cm long carbon strips. These 2 strips will make a strong bridge over the weaker retract openingthe strips must be just under the plywood part so it can rest and glued to themon top come the other 2 Plywood parts, use epoxy or PU-Glue to put it all together and make good contact with the foam. Also you can stick a steelwire in the holes to keep them inline(pull wire out before it starts to harden!). Also keep holes clean because I already drilled M3 thread in for you (put a little tape on the M3-nut)once epoxy has hardened you can drill 4mm holes under an angle, drill deep! into the foamfill holes with Epoxy glue and drive in the 4mm carbon pinsthe 4 pins glued under an angle will be good anchors deep into the foamuse a raw file or 80 grain sanding paper to deepen the large 70mm Wheel baynote my cutter: you need one as real FastFoamer!wheel fairing in place with some PU-Gluedifficult to find some scale pictures but the fairings look a little like this:use some 120-150 sanding paper and a block to round the wheel fairings, find pictures of full scale version to give them a nice shape
Main Gear: use 2 x 108mm suspension leg with off-set and large 70mm wheels(the strong&light Foam wheels from my shop fit and have also 4mm shaft hole). The suspension legs need to be modified a little so they move absolute free from the mechanic. Use a flat File to take some material off and check if you can see ‘light’ between the leg and the mechanic (when it is in up position)
my 4 kg mechanic versions come with 5mm hardened steel connection pin but you must cut 5mm off (sorry just a little too long..)wing of the A-10 is already heavy (many servo’s / cables / retracts..) so I changed the metal trunnion and used the much lighter Nylon version (you save 45 gram! on 3 of these) For model upto 3,2 kg these nylon version work just fine: no problem!you must see ‘the light’ between leg and mechanic (it should not block for reliable use)
Carbon Roving Spar:
deepen the servo leads canals so all the servo wires do fit in easy and tere is some room left on top of the wires. Do not forget to put an extra pair of wire for the retract mechanics!Here you see my succesfull experiment: I simply use PU-Glue to impregnate the carbon rovings (nice wet). Than I put a layer of wet EasyFoamFiller over my servo leads: just enough to cover the wire up.Put the wet Carbon Rovings over the servo leads and let it rest for 15-25 minutes I put in double rovings in the middle part of wing and 1 roving on outboard servo canalsThan when it is still very sticky you must finish it off with some more EasyFoamFiller. If you do the Foam filler on top you must watch every 10-15 minutes for Gas bubbles (the water from the EasyFoamFiller works as activator for the PU-Glue). It is very easy to push out the gas but you must check a couple of times during the first hour of hardening
Back to the Fuselage:
make the plywood sideskirts nice sharp with some sanding block.
bring the parts in position (check with wing) and glue with PU
clean up the hole (original Depron Skirts a way too big)
you have to remove some foam from the wing so it fits between the skirts
use some Scotchtape to protect the foam from sandingpaper, use some easyFoamFiller here to make surface back nice smooth
than there is an extra Cockpit lock that fits nice flush with nose radius (original has magnets but you do not want that for your FastFoam project). I am also not going to use (or is it: going to risk?) the servo canopy opening system, besides that I do not have enough chanels to use this gadget.
The nose gear:
this is optional 4kg nose gear plywood mountingset (comes together with the maingear mounting plates)
Take some foam out on the right side so you can get in the plywood parts.
the 7-layer bottom plate is not symmetrical so you must check position of Mechanic holes before you glue!
Nose Gear: use an off-set 108mm long suspension leg with large 60mm light Foam wheel for the nose gear
cut 7mm foam off from elevatorssame job as on the main wingvertical tail panels at 90 degreeuse smaller servo’s for the thin rudder panels: 6 gramms on my A-10. The steering is from innerside of the vertical fins. You can use same servo’s(servo’s run in same direction) and connect over a Y-Cable to only 1 channel of your receiverNOTE: the elevator servo’s are now heading in same direction so you can use same type servo’s and still connect with Y-cable to 1 chanal of your receiver. (original has 1 reversed servo used but I do not have these so just flip one servo over)I used 2 extension cables just to pull the Y-cables back into the tail end. Than disconnect the long extensions and plug the Y-cable to your servo’s. From receiver to the start of Y-cables you will need a 30cm extension cable (1 for rudder and 1 for elevator)
cut small sleeves forEpoxy rudderhorns with your Dremel and glue them into position with Epoxy. The Epoxy horns must be 100% same lenght (look close at the rudderhorns and you will see I made an easy shape to get them at same height). If you have 2 different lenghts in the rudder horns it could be very well possible that your model will start to roll in a looping…and you do not want that!
cover the servo leads up with EasyFoamFillerthere is often some expanded foam glue coming out on difficult locations: use dremel to cut it out and than use a fingertip with EasyFoamFiller to fill the sharp join so you have a small radius of FoamFiller (this is also good for easy glassing later)
I used 2 scratch pieces of 7-layer plywood and glued them together with the bottomside of the Jet-fairing (bottomside of the fairing is already glued to fuselage)
use the 2 plywood washers and glue them behind and 1 in front of the vetilation scoop (sink them with your Dremel).
Than drill 2-2,3mm hole and put M3 thread right through it (or use just screws..)
on outside of the Fairing I use the original connection parts (just did glue them to one side so I can not lose parts)
First and only re-shaping of this model:
the original kit fairing has sadly the shape of a biscuit Tin..but easy to give more scale look! lets start with the airscoop: this should be more narrow:
like this after cutting with sharp knife blade and some sanding
than I see here another ugly straight section that is not scale:
After some sanding it should be curved: (also It made the rear exhaust flat and will paint this flat surface black later)
here below we have the “Biscuit Tin” view. The front section of the Fan housing is to long straight and should start to curve much earlier
you must work on first 5cm around the airintake, just sand it sharper and even a big flat around the sides
same for last 7cm of the fairing: make almost it a little Flat ! all around
time for Glassing!!
first we have to prepare the model and cut all rudders off! Don’t cry: we are going to replace them later by real FastFoam Hinges!
first check with a fingertip of EasyFoamFiller for sharp corners and fill them with small radius of filler. You will find them around the vertiacal fins, stabilazer to fuselage join and whell fairings (below) cut the trailing edges most easy with a lose blade from your steelsaw
Cut all plastic hinges
pull the them all out just like your dentist would do..before you can start glassing it is needed to sand complete model with 150 or even 180 sanding paper . Fold the paper double and sand with flat hand, after that you clean the model from dust.
now you can put on a sheet of 25 gramm glass and start painting over the glass with PU-EPS Finish ( I have made a headcam movie of glassing this wing that I will put online)push the thin glass also into the rocket fairing sleeves
cut it in at corners (like you do with oracover)
take it around the corners with your brush (all go’s very easy and quick with PU-EPS Finish and 25 gr glass)
do not spend much time on problems were to much glass foldes together: it is gone with a little sanding paper before you know(but let it dry first!)
do not spend time on balsa trailing edges: just let it hang over the edge (sand it off when dry)
splitup the glassing sections when object is difficult. Because of wheel fairing I used 4 parts to cover the bottom wing sidecut it in with sharp scissorsnow I make one side of the rocket fairings wet with PU-Finish and bring them on the still wet fresh glassed wing. Push it in the pockets and use needles to keep them in position. the PU- will act like glue. Note: do this when underside of glassed wing is still wet and select all 6 fairings because they have all diffent size but also left- and rightwing angle! (best give them numbers before you start) Next day you can sand the topside so you feel no start and finish af you glassing work from evening before. Useing PU-EPS Finish makes sanding very easy (much easier than Epoxy!) . Use dust mask if you do glass sanding (with all sanding but specially with glassfibre)
below you see how easy the 25 gramm glass is pulled around sharp edges: use only 25 gramm glass for light and easy workanother example of 25 gr glass next day I put a stripe of glass on top of the rocket fairing and pulled over the sides down on the wing. you can fold it around the front and leave it drying at the sharp rear
Putting Back the Rudders and Flaps:
make cut with fresh blade
push them in and clean what is sticking out. let it harden an hour before you are mounting to the other side after an hour you put some PU on (also in the other cut of wing panel). When rudder is pushed to position it is needed to wipe the excessive glue away with a folded piece of toilet paper
By this time your model should look like this, if not you must buy some reading glasses! (like me..) this twin 70mm jet is as big(or bigger) as many 90mm JetsThe fantastic new JePe JET70-6s 7-Blade will provide super power(also on only 5s) Current on 5s is only about 55Amp (max60) so you could use one big 5s 5500-6000mAh battery or 2 smaller 3300 30c packs. I have tested these new very dynamic Fans on only 5s in my big F-18 of 3,2 kg with 2 old 4500mAh/5s packs on board: plenty! of power even for a fighterjet like the F-18 (have a look in my shop at the JePe JET70-6s 7-Blade)
Like my old fiberglass A-10 it is possible that I need a little trustline correction to balance the high positioned Fans. If I need extra parts to tune this model than these will be shipped for free (the Fans are already tested and I will testfly the A-10 also soon: its sitting here with all servo’s ready installed…a matter of days now)