horsefeetky

dave what size battery packs did you fit into the nose so well.

also what about using the simple dubro disc brake on a nose wheel to meet the usa standards many have done this with small jets and it does fine.

Dave Wilshere

The Rx is a 2s 1600 li-Po and ECU 2s 2200 Li-Po. I Dremel the front fuselage former lip down flush with the battery bed, then the 1600 sits vertically and the 2200 is angled against it.

I guess you could use one, there is not a whole lot of space around the nose wheel though in the pocket we formed to keep out muck

horsefeetky

dave
any suggestions for brake or brakes on this little bird to make it conform to the usa rules. maybe the old dubro 157 friction nose wheel brake or maybe some of these modern electric brakes for small jets.

also the new builds are not using the uat tanks.. only a felt clunk in the main tank correct..........

do you use differential on the aileron or not needed. i see they need separate channels for the crow to work on landings. i think i will put the flap to elevator mix on a curve mix and use my slider for function to control the amount of flaps i get.

i like your nose cone attachemnt using bullet connector.. copy that for sure.

Dave Wilshere

I'm sure that Ripmax have a set coming.

These two don't it's not critical on this tank shape and small turbine.

No differential on mine. I do have 2mm crow on full flap

Dave

horsefeetky

thinking of using
kst ds215mg in wing and rudders
kst ds225mg on elevator. this is 10mm thick servo it is overkill at 7kg but i want the hv versions of kst throughout.

did you use wing servos in the wings or std type mini's

Dave Wilshere

I use KST 115 and 315 in wing and 145 in tailplane. Rudder is 113

Dave

horsefeetky

do you run a bec on the lipo 2s pack for the servos......

also the ripmax site mentions using a separate battery for the retracts do you power them from rx or use the turbine pack. either way ripmax shows a 6v pack in the picture for the retracts. will they be ok using 2s lipo. 7.4 plus is a bit high for those electric retracts. most dont like over 6-6.6v

i will follow your 112 flight proven design on my build without further question as if it works dont worry...........

Dave Wilshere

I have a Powerbox Digi Switch. This takes the 2s Li-Po down to 5.9v. The retracts are run straight off the gear Channel at the same 5.9v the servos receive.
The Powerbox switch is a latched, fail to on, switch regulator, each flight on the Mini even with an iGyro 3e working uses less than 80mA

Dave Wilshere

Plenty of flights on my Mini this weekend at our JMA Bruntingthorpe event, Steve Roberts stole a couple or three flights over the weekend.

horsefeetky

dave sent you pm with a few questions on the igyro 3e any help welcome
joe

Dave Wilshere

Sorry been in Germany for a few days. Will answer now

Dave

horsefeetky

took only one week to get here to ky in the usa from ripmax... pretty fast service via dhl

dave my p20 has the external pump and valve where did you place them in the fuse for proper balance. i have two 2s 2200ma lipos in the nose cone side by side also using a igyro 3e i will place on one of the removable shelves in front of the fuel tank the rx on the opposite side.

thinking of using a magnet in the inside of the nose cone for easy removal and clean look outside. i saw you bullet connector trick for there also good idea.

Dave Wilshere

All P-20's are external, way too small for anything else!
The pump and valve block go under the right hand plate next to the nose wheel cover, I wrap the pump with a Velcro strap and the put the opposite Velcro on the fuse inner surface. I put a notch in the plate for the pump cable to come through and the ECU sits on the plate.
The left plate has the gyro and Rx on it, underneath is all the wires tucked away.

Magnet will work just fine on the nose cone.

horsefeetky

i am ready to fly but the balance in the instructions mention 115mm mine is a tad nose hvy at that mark it is perfect right at the front of the gear mounts.. what do you think of this.
i got it all in the fuse. spektrum telemetry 8ch rx, gps,jetcat telemetry module,brake servo,igyro 3e, no uat just felt clunk in tank.

Dave Wilshere

If that is with no fuel in the tank, it's going to be quite nose heavy in flight. How much does it weigh with all that extra stuff in there? Little models don't deal well with higher wing loading, light is everything.

Dave

Bob_B

My Feedback: (11)

Horsefeetky are you in the Lexington area? I would like to see your model fly sometime.

horsefeetky

yes im behind woodford reserve in versailles

dave
it weighs in at just under 8 pounds and instructions mention 7.5 as the target weight

here are the two battery packs i have in the nose lipo for turbine and life for servos. i attached a pic of the tiny servos i used they are kst 315mg in rud,ail,flap,steering, then kst 225mg in elev and a micro on the brake wire. i can remove gps and telemetry for jetcat but it would yeild only an ouce of savings.. i find no extra weight other than battery pack size i can change to make any difference. also i can relocate one battery pack into the canopy area to change balance but im just a tad nose hvy at the stock 115mm now and comfortable at 120mm where the front of the retract mount pocket is.

please advise if my balance point is right from your findings from flights

thanks a bunch for your help

horsefeetky

here are the packs im using as of now

horsefeetky

the packs weigh in at 4.75 ounces each in the nose do you think with 8 servos in use i can go to a smaller rx pack it could be a lipo to up the current and lower the amp draw as they are all hv servos in use.

Bob_B

My Feedback: (11)

Do you fly at the Lexington model airplane club

Dave Wilshere

My packs weight 4oz and 3oz. The 1600 2s Li-Po Rx pack drives a PB Digi switch to give everything 5.9v. I get a weekends flying from one charge.
I use KST 315's too in one of mine. I keep cables and tube as short as possible, you would be surprised how much tygon and HD JR extension leads add to a model, I speak with modellers who say 'ah that weights nothing' meaning not a lot, but all those nothings add up to something!
I have fuel in mine now, but remember is was around 7.6lb dry new.
I have flown one with airspeed sensors and 'gizmos' and it was over 8lb, it still flew OK if you kept things smooth till it burnt a little fuel.

Dave

authomassen

Hi Joe,

When I had that exact motor in my mini avanti, I used a Gens Ace 2s 1000mAh lipo for the turbine, and a Turnigy 2s 950mAh lipo straight into the receiver. RX power with two male servo wires soldered into a EC2 plug, no switches to fail. Two flights used about 200mAh out of the turbine battery, and considerably less out of the RX battery. That way, as long as the turbine would start, I would also have power for the radio.

Total weight for the two batteries were 114g/4oz.

horsefeetky

i may go with smaller battery packs to get the weight down and help on the balance a bit. i can juggle them with the ones i have to achieve the proper perfect cg as well as get the weight down to 7.6 pounds as dave thinks his was at.

dave
is the stock cg 115mm a good flying point for the plane over all.

horsefeetky

dave i went smaller on the battery packs so the weight is now under 8 pounds and i can set cg where you tell me is best..please advise as maiden is due anytime now after i hear back from you on cg spot.

Dave Wilshere

Mini Xcalibur additional notes



Congratulations on buying your Mini Xcalibur, the third member of the Xcalibur and definitely the cutest!

Before starting the small amount of construction required, it is good practice to assemble the airframe to check everything fits as expected. Work the tailplane screws into the fin top to check they are clear of glue.

The Carbon wing spar is much easier to insert if you chamfer the ends with a 2mm lead in. A smaller chamfer on the anti rotation pegs will also aid assembly. With the aileron servo covers removed, insert the wing spar and ensure the spar goes fully into the wing clamp. Add the screw to the clamp and check it tightens fully. The wing fixing screws provided are a little over length, we supply 4 thick washers to stop the top skin being marked.

Before gluing any of the hinges in position it is good practice to check the film covering with a medium heat covering iron. Pay particular attention to the edges and faces that form the hinge gap.

Use a sharp scalpel to clean the hinge openings before proceeding to glue the hinge points. We recommend using Hysol 9462 to fix the hinges, applying the adhesive with a glue gun and nozzle will also guarantee less mess! Laying the control surfaces on top of the flying surface with hinge holes in line will allow you to check the holes are central in both surfaces. If any have crept off centre use a small coarse round file or Dremel to adjust.

Before gluing any of the servo mounting blocks in position rough/score the wood to raise the grain, the heavy resin plywood needs keying for a good bond. We provide two 4mm plywood inserts to fit in the rudder servo openings to suit our supplied servos. These will need some sanding for a perfect fit.

We mount the flap servo mount to the lower flat area channel with the servo arm at the front. The mount is already trimmed for the KST 115 servo *. Use the single long arm provided with the servo.

The control rods threaded at each end should be used on the main controls, a single rod with Z bend on the flap. We include 6 x MPX M2 clevis for Ail and Elev controls as the supplied units are not the highest quality, but we are using successfully on the rudders.

The KST 125 elevator servo requires a small square trimming for the third mounting lug. KST 145 fits straight in.

Before assembling the fuel tank, look through the fitting hole and ensure it is clean and clear. Flush the tank with methylated spirit. Don’t use water is takes days to dry out! Once complete pressurise the tank a few times to ‘exercise’ the joints, and then submerge in water to check for leaks. We provide a felt clunk and suitable overflow fitting for the P-20.

When you install the retract set, it’s very important the legs and wheels do not foul the fuselage, electric retracts have an over current protection that will stop the units operating. If flying from grass, we recommend fitting 3mm packers under the nose retract unit.

The slots in the fuselage for the closed loop wire need to be large enough to allow the crimp ferrules to pass through easily.

It’s possible to fly the Mini Xcalibur with a 7 channel Rx, with two Y leads for rudders and nose steering. Using a Y lead on the opposed rudder automatically make them work in the correct sense. A nose wheel steering servo will be required with the correct direction to match the rudders-if you have bought our set this is the case.

9 channels are required if you want individual channels for each function.

The nose cone is designed to be retained by a single screw in the nose, but a 4mm gold connector works as a quick connect attachment. Drill the + for the 4mm socket and epoxy the male to a small ply block and the nose cone.

The balance is achieved with a 1600mAh 2s Rx pack and a 2200 2s Li-po ECU pack. We use a PB Digi switch for the radio.
Balance the model with 1" (25mm) fuel in the main tank, hopper full if fitted at 115mm back

If you fit a 2oz MAP Hopper this goes on top of the nose pocket facing rearwards.

The manual control movements are good for initial flights, but note the 7mm Aileron movement is at the tip and a low setting. We use 3mm of CROW at full flap.

If you fit an iGyro 3e we started at 25% gyro gain and adjust to your total control movements.

As with all small jets sharp changes of direction and very slow flight should be avoided until at least half the 1 3/4lb of fuel is burnt! Fly smooth and the Mini Xcalibur is very groovy.

Sorry was at Weston Park and only just back

Dave