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Nov 11, 2016, 05:41 PM
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Small changes to V977 & k110 (+ a few K 120 ideas) for better results

List of improvements to v977 and xk k 110 . All comments and suggestions welcome . fotos in comments section
1. oil and grease bearings including motor and joints , such as singer oil and white grease. I use a 5mm syringe with long needle tip to administer .
2. better battery original 450ma 25c to GOO 520ma 30c or Nano tech 600ma 35-70C or Graphene 600ma 65C
3. reinforce canopy weak points with glass fibre strapping tape ,splits at bottom upon impact.
4. reroute servo and tail motor wires to starboard side of frame away from motor and moving parts. no rubbing.
5. use thread or fine fishing line to secure wires, cables ties cut the delicate covering on the servo wires.
6. add extra heat shrink cover to tail motor to protect wires
7. tail boom reinforce by wrapping 3.3kg (7 pound) fishing line at 3 or 4 points and fixing with CA glue. Boom is made of two parts and when split flexes (bad)
8. reinforce main mast with 6 ,1mm rods of carbon fibre CF / CA to prevent the weak center part of mast cracking upon impact.
9. anchor servos with tooth pick at underside of frame , prevents servo moving up out of fix point.
10. mount more powerful tail motor from 7x 15mm to 7x 20mm ( SUT works well) and larger rotor from 37 original to 43 mm. k120 or 48 mm. Mcpx 48mm black rotor is nearly unbreakable.
11. reduce weight improve cooling air flow and make canopy more flexible by cutting "Eyes" or windows into sides and trimming upper parts away.
12. tether landing gear legs with fish line 3.3kg to create a "shock absorb" effect and prevent lg breaking on hard landing , the line will snap instead. Soften plastic legs to prevent breaks by boiling in water for a few minutes (see direction in comments)
13. Increase luck by obtaining an Italian "horn" red color preferred or gold. This is believed to work. We take our luck seriously .
14. add a bit of heat shrink as a strain relief to the battery power plug if you have big fingers , it helps to prevent the wires from pulling out
15. move buckle links from short balls on swash to long ball if a little more movement is desired
16. mount metal tail holder, swash, head and grips, note all the extra weight , then remove and restore the plastic and save the metal junk for the shelf queen
17. try other blades such as v931 , note changes to power and flight
18. find throttle calibration instructions for esc ( this is not reset, or stick Cal,it is throttle cal ) and follow if v977 does not start until late such as 20% on lcd readout. this cal works too ! See pictures #18 for instructions and jumper cable.
19. Stick Cal for x6
XK Innovations X6 Stick Calibration (0 min 36 sec)

20. "Servo saver" cut servo horn to allow slippage during impact which saves gears from stripping.
21. add navigation lights to aid in low light flight. this is easy , needed are 1 or more leds, 3mm 2 volt. resistor ,22ohm, wire and plug from spare tail motor assembly tomplug into to "extra" motor jack on fc board next to the tail motor jack.. see picture #21 for detail instructions . I did this to help in low light and distance and it works.
Last edited by mikroll; Jan 28, 2019 at 08:24 AM.
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Dec 21, 2016, 03:53 PM
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Pictured changes

# 8. Main shaft reinforced with carbon fibre rods to prevent cracks upon impact
#4. Wires rerouted to starboard side away from motor and moving servos arms
# 7. Hollow tail boom reinforced with fishing line and CA glue at four points ( white ).
Last edited by mikroll; Mar 21, 2017 at 10:56 AM.
Dec 21, 2016, 05:02 PM
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Pictured changes 11&12

11. reduce weight and make canopy more flexible by cutting "Eyes" or windows into sides and trimming upper parts
This may also provide more cooling to the esc too. And prevents motor rubbing canopy.
12. Tether landing gear with fish line to absorb impact , line breaks instead of the lg legs.
Last edited by mikroll; Jan 13, 2017 at 12:04 PM.
Jan 11, 2017, 06:29 PM
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battery cage modification for fat battery

Helicopter has described how to modify battery cage to accept the larger nano tech and graphite battery sizes. Pictured is the cage after being boiled In water. He also says that this works well to reshape bent landing gear legs.
Ibeen messing with the old boiling water thing with plastics and as a side discovery found a nice easy way to mod the cage for the graphene and nano techs ,after taking the 2 dots off the first bar push a cylindrical shape through the cage (I used a brush) so it bends out the back ones a bit then dip in boiling water for 30 seconds or so remove brush ,keeps the shape fits lovely and no weakening of cage (possibility strengthening ) to be honest you probably get away with not taking off the dots at the front .

ps also handy to straighten flat landing gear
Jan 11, 2017, 06:40 PM
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well done on such a list
I used to hot glue the rear tail motor holder to strengthen possibly also upgrade to jst connections ,personally I use 20AWG cable and prefer the silicone as bends a bit easier ,also slightly easier to detect breaks in the cable

solid boom is a good way to go though moves the breaks to frame and tail motor housing

oh and don't forget canopy cracks in the middle at the top a lot of the time .

and last thing is a crazy thing ..that sevo plate cover at the back .if that rear screw hole ( the one between the servos) splits you loose loads of strength to box section where the boom goes in as you rely on just that bar between the two screw holes on the frame (2 frames to discover that )

bear in mind in some crashes when you reinforce any part of this heli you just move the break point somewhere else ...but still believe a lot of them slow down the orders for parts lol

ps going to try no 13

well done again dude
Last edited by halicopter; Jan 11, 2017 at 07:46 PM.
Mar 03, 2017, 05:25 PM
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Lights , easy way

Both k110 and v977 have led lights on rx board . So if the canopy can be made transparent then the light will shine through. 1. Remove the white , blue and black paint from inside of canopy with fine sandpaper. 2. Spray paint glow paint to inside of canopy or leave clear. 3. If more light is needed cut out eyes or windows in canopy ( and also prevents motor rub).
I found that the glow paint works well as can be seen in the attached pictures. the entire canopy "glows" like a light bulb!
Last edited by mikroll; Mar 04, 2017 at 09:42 AM.
May 06, 2017, 08:32 AM
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couple of upgrades I swear by

pictured below is my landing gear up grade using every day dental floss ,I only do the front to keep the overall give and totally works .. just make sure to leave some slack

the other is the tailholder up grade without it my holders only last a few crashes or motor ejected ,also can help wag , just some hot glue round box section to motor ...ive found anything harder than hot glue will hold too well and break boom or frame (if solid boom fitted )

recommended with solid boom

as a suggestion for other to try is reinforcing frame with uv hardening glue
May 06, 2017, 05:08 PM
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20. Servo saver. Plastic horn cuts with sharp blade . No need for the screw . Update that since loosing several horns and links have now put back the screw!
Last edited by mikroll; Aug 01, 2017 at 04:53 PM. Reason: Update
Aug 26, 2017, 07:09 AM
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#18. Throttle cal directions with jump cable

Throttle cal is easy to do. Pictured is the jumper cable made from spare servo cable extender and Losi plugs.
this set of instructions were provided by birdbarber . thanks.
Note same jumper cable setup is used for esc cal
Last edited by mikroll; Dec 01, 2017 at 10:29 AM.
Oct 17, 2017, 04:01 AM
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Other locations for good tips
Jan 18, 2018, 02:41 PM
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#2 led lights

# 21, pictured are the led lights attached to the heli , the set up for 3 lights , white at back, red on left (port) side and amber on right. tried a green on right but it was not bright enough. the white is super and the low light and a dark background against the trees worked very well. I first tried a single whit tail but found that the three work very well ( just like in real life for boats and aircraft) pictured are 3 leds with 3 22ohm resistors, but also works to set up, 3 leds connected in parallel to a single 47 ohm resistor. I am sure that there are other ways to connect with less weight and parts.
Note. If using an tail motor plug and wire assembly that the black wire is the positive dc volts , at least on my plug it check it.
Last edited by mikroll; Jan 20, 2018 at 06:01 AM.
Jun 02, 2018, 06:26 AM
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XK K120 extra bits keep it flying (I hope)

+XK K120 tail fin is weak , add enforcing rod to leading edge or replace with cable wrap when it breaks. see picture
+tail rotor works well but is easy to crack at hub and base of blade, replace with strong nanomcpx black 48 mm rotor which never breaks!
++servos will for sure last longer if servo saver mod to horns is done. and anchor base to frame with toothpick in tab hole.
+go to k120 page and watch closely what others have done to save board from crash damage.
+bundle board in fine bubble wrap foam to help in crash as forward part is exposed
++add fibre thread tape to top sides and bottom of canopy and add fine bubble wrap foam to inside of canopy ( see picture) to protect board in crash
+tether forward landing gear legs to prevent spreading during hard landings and tether lg to frame front and back to prevent fly off from crash
+add JST red plug to back of battery plug for use of batteries with jst 2 pin plugs or just remove the original plug and go with the jst. which is then cable wrap +attached to the landing gear
+oil and grease all moving and sliding parts.
Jul 13, 2018, 01:10 AM
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K120 tail motor mount

1. Tail motor mount was not secure allowing it to move and turn . Secured by drilling a small hole for a screw to hold it . Pictured

2. Tail was “moving” and off centre, this was caused by a crack , pictured, in the tail pipe mount on frame. Created erratic flight and crash as tail was not secured.
Last edited by mikroll; Jul 23, 2018 at 01:16 AM.
Jul 22, 2018, 05:18 PM
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k120 servo failure , why

k 120 number 3 arrived with a servo not working. servo would not move and became very hot. a hot servo is classic when feedback loop is not working properly such as a jammed pot in this case. the servo arm axle which drives the pot which sends the signal of the arm location so that the motor can drive gears was jammed. this ( pictured) was due to the pot axle being pushed ( mounted) off center . this jam causes the motor to heat to melting as it can not move the gears to the proper spot . can be seen in pictures how the gear ( with the screw) and axle a offset and not straight . this creates the bind.
Nov 25, 2018, 08:30 AM
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XK K120 wire route & battery

Pictured: JST battery plug direct to board, teather landing gear, tie wrap tail fin, .

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