Goblin - Project details and Build issues

[windwizard]

UPDATED: PROJECT & BUILD "ISSUES" DATA BASE

SETUP DETAILS

Flight Style: Sport, Big Air n/a
Headspeed: 2094 power / 2178 general /2241cruising
Motor: Scorpion 4525-520 (92.8 % eff.) .......................................... $349.99
Motor lube Scorpion Motor Bearing Lubrication Kit..................... $5.00
Pulley: 21 Tooth (optional Pulley = 9.71:1).................................... $16.00
FBL System: V-BAR Full size (blue) ver. - 5.2................................ $319.99
Hyperion phase sensor............................................ ...................... $9.00
Governor: v-bar

BEC: Western Robotics Hercules Super BEC................................. $100.00
Bec Adaptor (WR) Used for back-up battery pack.......................... $12.00
RX: (2 remotes) Spektrum DSMX Remote Receivers...................... $70.00
BEC Backup Pack: 800 mAh NiMH buffer pack & charger.............. $30.00
ESC: KONTRONICS Heli Jive 120+ HV(v11)..................................... $539.99
Kontronik Pro-disk Programming Card.......................................... $128.00
Cyclic Servos: Outrage BL9180 (8.4v)............................................ .. $380.00
Tail Servo: Outrage BL9188 (8.4v)............................................ ...... $138.00
Futaba replacement arms for Outrage servos # 04021..................... $17.00
(arms replaced due to tight fit next to servo support frame)

Servo Extension Tail servo............................................. ................. $2.00
Main Blades: 690mm Stock SAB n/a
Tail Blades: 115mm Stock SAB n/a
Lipos: 2nd choice Turnigy 35C 6S 5000mah(x2)................................ $120.00
Wire red 10 guage .................................................. ......................... $4.00
Wire black 10 guage............................................. ............................ $4.00
EC5 connectors For Battery Harness (4 set)....................................... $6.00
EC3 connectorsFor BEC (2set)............................................ ............... $2.50
M2.5x10 Screws (1bag)............................................ ......................... $4.00
(longer screws needed for mounting Torq servos)

Shrink tube (green)........................................... ............................... $15.00
Tri Flow synthetic grease with teflon............................................ ... $10.00
Glue gun............................................... ........................................... $9.00
Shoo Goo............................................... .......................................... $6.00
Swashplate leveler (true-blood for trex 700 nitro)............................ $25.00
SAB GOBLIN 700 Flybarless Electric Helicopter Kit.......................... $1000.00
MISC. COST FOR EXTRAS AND SHIPPING TAX................................ $75.00
___________
TOTAL $3422.00

__________________________________________________ _____________________________


Goblin "build issues" data-base.

HEADSPEED CALCULATIONS: (Calculator at readyheli.com)

http://www.readyheli.com/headspeed-calculator.html

Includes the update/repair for the wrong gear ratios (listed in the 1.3V manual) showing the pinion drive gear having 19 teeth not the actual 20.

Example for a Scorpion 4525-520 motor

Result for calculation using 21 tooth (OPTIONAL) motor pulley

• (will keep rpm above head wobble zone)
• Estimated lowest voltage during flight: 42.00
• Lowest RPM (due to voltage and efficiency) : 2023
• For + performance, keep req. RPM below: 2094
• For target performance, keep req. RPM below: 2178
• For - performance, keep req. RPM below: 2241
• 21t = 9.71:1 gear ratio for headspeed calc.

Tech notes:


"Tips and tricks" video threads in SAB Forum cover...

• belt tensioning
• blade grip arm assembly
• gluing bolt to main gear for easy assembly

ALSO - See Mr Mels vbar video series in Mikado support area of Tech Forum

• Longer metal bolts needed for Outrage Torq servo mounting Replacing the M2.5x8 screws with M2.5x10 screws
• Servo extension needed for tail servo safety break away
• Glue gun needed to glue servo cable to inner boom and elec. componant connectors to be secured to Vbar recepticles

Frame issues

Manual 1.3 - page 26 recommends de-burring the edges of the carbon frame but this should be done as the "first order of business" not after the heli is almost fully assembled. All the CF frame pieces are extemely sharp and should be dulled - it is an easy job if completed prior to assembly.


Motor issues

The motor shaft should be cut - required length is 28.5mm

If not cut, the maximum height of the battery is 50 mm

If you cut, then maximum Battery height is 60mm

Maximum motor height is 68mm.

For greater motor height it's necessary to modify the opening in the canopy.

SAB GOBLIN USA - Says..."Quantum 4530 is delta wound and there is no issue using Kontronik Jive ESC with it."

Align MX 700 is perfectly compatible

Scoprion 4035-560 is listed as a motor suitable for general flight in the Goblin
manual p28. but the mounting holes dont line up for all four screws and you will have to mount motor with only two screws! (patern is 30mm spacing)

Scorpion 4525-520 Ultimate - mounting pattern matches the 4 bolt motor plate

Warning! check resistance from shaft to motor leads - should be infinite ohms. If not, the mounting screws could be to long touching motor windings, this could cause ESC FIRE and failure in flight (This issue is a general warning not specific to the Goblin)


Rotor-Head Assembly

Tech note from SAB - "Use the special washer(s), page 23, if you planning to run over 2000 HS (washer is circled on page 15 of manual 1.3)

The head is already assembled without the H232 part. (only for early kits)
If the headspeed is > 2000 rpm then the H232 part has to be added (pag 33).

In any case the blades have to be really tight (pag 33) and a small quantity of gear lube has to be added to the main gear.

These shims increase the damper preload therefore increasing head rigidity. Please make sure your main blades are tight on the grips, you should be able to violently jerk the head in both directions and the blades should not fold.

Failure to tighten the blades properly and/or run incorrect dampening preload can result in a boom strike.

If you remove the shims on the head you won't have any wobble issues at low headspeeds. Wobble present at 1900 rpm."

All later shipments of Goblins (after 1st batch) already have shims installed!


Thrust bearings

Some are reporting that the Thrust bearing is bone dry, others reported bearing installed backwards.

Note: You must disassemble factory head to make sure everything is greased and loctite is applied properly.

SAB is recommending Tri-Flow clear synthetic (PTFE, Teflon) grease for thrust bearing/bearings . You should be able to get this at any bicycle shop.


Mainshaft

Vertical play in the mainshaft occuring due to factory hole being larger than retaining bolt that attaches collet to shaft.

This was by design to allow collet to be position to "take up" any axial/vertical slack in mainshaft but the problem is that it also allows the collet to work its way down the shaft over time.

One solution mentioned...
Use align .5mm trex 700 main shaft washer in between collet and bearing, this will permanently fix it so that you need not relying on a friction fit of collet to hold the assembly in place.

http://www.helipross.com/align-t-rex...er-hn7075.html


Drive Pulley WARNING (ALL 3 pulleys possibly)

SAB Goblin 700 Service Advisory #2 (20th March 2012)
Despite extensive testing, it has come to our attention that one or two main drive pulleys (H0016) have had the pulley flange loosen from the pulley during flight.

We are working to rectify this problem, and have designed a new system to secure the flange to this pulley. Replacement pulleys will be shipping soon – if you have purchased a Goblin, please contact your dealer to arrange a replacement.

Others are now reporting crashes due to this problem and the same problem being found on the motor pulley and tail pully.

DEFECTIVE DRIVE PULLEY REPLACEMENT FROM S.A.B.


NOTE: Replacement tail drive pulley has an extra tooth from origional.
Was 36, now 37, for added tail authority.


PULLEY SHAFT (Z60)

Z60 pulley shaft must have a little up & down play in the range of 0.2-0.8 mm , confirmed by SAB Tech Dept


Jesus Bolt failure

"Advisory notice to all, the "Jesus" bolt on the secondary shaft. (The upper one above the slanted pinion Z20) failed in flight on my Goblin.

...I have replaced all these with Align 500 head bolts . The bolt that holds the 500 head to the main shaft. It's a perfect fit and has shoulder the whole way through the pinion gear, it works perfect - will not break."


Drive Shaft Bolts - WARNING

There have been reports of bolt failures of those being used to secure
the pinion and pulleys.

SAB has announced on their website (4-10-12)..." We will replace all the bolts
and send to distributors in about a week. New kits will have new
shouldered bolts. All of our bolts are DIN 12.9, highest quality bolts and screws.

Alternative resource for shouldered bolts if your cannot wait for SAB

http://www.alignrcusa.com/index.php?...oducts_id=2385


One Way bearing

"...Brass surrounding one way seized on intermediate shaft.
Took it apart and sanded/cleaned and oiled, all good now.
Another post - "one way" was dry as a sun baked bone, needed grease."

The One Way Bearing should be greased during build!



Tensioning Spring - (tail drive and main drive)

Tail belt tensioning spring was not symmetrical, the length of the bends on the end were different. The short end goes up and the other end goes down, (the shorter side on the support, the longer on the arm.) Sab will update the manual as soon as possible.

Spring issue is related to its orientation - needs to be clarified in the instructions manual. Also, spring may need a dab of epoxy to stay put in mounting hole.

Drive Belt Tensioning Spring - Also could use a tiny dab of epoxy to glue the Drive Belt tensioning springs into the motor mount, - it just makes mounting the motor unit that much easier.


Drive Belt Life?

Depends on the type of flight ...average is over 100 flights
Belt care - (main and tail)... food grade silicon spray to lubricate belts.


Batteries

Use Velcro to help hold batteries in tray – (back of tray is open)

Battery Tray can be installed in one of two positions to allow for slightly
larger batteries if necessary.


Canopy tips

May have to ream out mounting holes to make them line up correctly

Use the foam pieces pushed out from the blade holder to make the canopy fit without sliding to one side. Measure and cut two pieces off with the rounded sides glued to the canopy.

Duct tape inside of canopy over mounting holes to strengthen
canopy from cracking when flexing during removal and mounting

Canopy modification to minimize stress damage: (install 5/16 gromets)

Had to ream out the canopie holes just a bit. With the new gromets mounted on the canopy they slipped over the face of the mounting studs and push into position with a little finger pressure. You still get 2 3/4 turns on the threaded fasteners as they thread tight against the gromets.

One detail - you need to ream the holes in the canopy large enough to allow the gromets to expand just a little bit for when you push them into position over the top portion of the mounting studs.

..





Canopy placement and removal tip

Always put the swash all the way down. Grip links facing front and back. Very easy to slide on the canopy that way - otherwise it can be a real fight!


Boom paint

Some booms needed to be sprayed by local body shop with
a 2 pass clear coat.

I buffed with a polymer treatment product to make the matt finish
shine like it was clear coated


Flybar sensor position

A FBL sensor does not need to be centred on the heli, it just needs to be square to the mainshaft and centerline of the heli. it is important that leads has some flex in it so as to not transfer any vibrations into the sensor.


Swashplate quality

Swash has a little vertical float to the centern ball. Turns out that
“I2 Swashes” are built with the same loose ball and are very good
swashes - should not be an issue.


Main-gear fit and finish

File the plastic away that overlaps the hole in the main gear, makes for a perfect fit on the main shaft.


Tailboom Warning

Check clearance between the blade at "0 pitch" and top of boom.
Min. distance is 145 cm, if less, - add tape under nylon bolts.

FAILURE to rectify this issue may allow for a boom strike!!

https://www.helifreak.com/showthread.php?t=395680

Shoo goo the servo lead (servo inside the boom) down and tape lead to servo, (glue gun application are already being reported to not stick long term to the
inside of the boom)

Chamber the edges of the aluminum block with a small flat file,
so that the plastic bolt heads can easily line up and slide in.

WARNING! Don't over tighten your nylon tail mounting bolts or they will snap!

Quote ..."I snapped one off with the supplied wrench! Just get it snug,
the carbon plate on top will hold it in place,"

Home Depot sells nylon bolts that fit perfectly in case SAB nylon bolts snap.


Boom spacer - Failure

Don't overtighten, and may want to consider not using CA but rather use epoxy
..."I expoxied that sucker to the side of the boom. CA is worthless on metal"


Ball link issues

Blank side of the ball link is pressed onto the ball- SAB stamp faces out.
Ball links are tight, will have to wear in- if too tight then ream them out


Servo installation and related issues

Servos for swash must be installed using spacers provided (For Mikado and
Outrage servos (rubber and carbon fiber) this will require 2.5mmx10mm screws

Servo arms with Torqs servos need to be replaced with mikado or Futabas - both work perfectly on my Torque 9180s.

..."I got the proper resolution from my Vbar and also the arm spacing put the links as vertical as I could measure them. The red also matched the servo color (futaba arms). part numbers liste on first post."


Tail set up issues

Tail rotor stalling due to over inducing pitch -…We reduced the travel to 20 deg Left and 30 deg right, which resulted in a more even VBar setting of 76 and 74.

Please note that the tail servo endpoints are at 76 and 74 and as this is below what Mikado recommends, it still works perfectly. One cannot get the servo arm shorter due to the fixed position of the push rod guide and any shorter on the servo arm results in a push rod that binds in the guide.

General consensus is to add pitch mechanically 3 or 4 deg. (for hover) and set servos centered and pitch arms at 90 for the rest of v-bar setup.

There is a slight amount of radial play in the tail grips because of the thrust bearings

Tail thrust bearing (factory assembled) -dry as a bone without grease - must disassemble factory tail to make sure all is greased and that loctite is applied properly.

...Logo 600 CF tail control rod is longer than stock goblin rod and can be used to make a precision cut and fitted rod, (should be long enough to allow the servo to be turned 180 to allow servo cable to be positioned more accurately away from the tail belt as well)

Flanged bearings - Check the flanged bearings (HC414-S) in your tail side plate / fin! They came loose in some machines and made a strange noise. A little bit of CA and everything was ok,


Main Gear Break-in (forum opinions)

Manual specs...
"A lite lubricant such as WD-40 is recommended for break-in to allow gears to seat properly since there is no lash spacing on the goblin."

A more effective lubricant will only prolong the break-in period. (Normally 5- 10 flights)

WARNING: concerningn main-gear break-in.
From experience: (as stated on the forum)

"I did not use WD-40 as recommended by SAB. Instead I used triflow synthetic grease --> big mistake. The grease + black gear powder (from initial wearing) + dirt gummed up and together this combination somehow has worn the gear so quickly that after 10 flights, I already have tons of backlash which is definitely NOT good.

Replaced the maingear with a new one and used WD-40 for BREAK-IN --> great success. After a few flights, WD-40 flew away and the gear backlash has been perfect!"



GEAR RATIO ERROR IN MANUAL 1.3 – REVISION BELOW

In the manual, the helical pinion (up top) is a 19 tooth gear, but in reality it is 20 tooth

Corrected ratios for calculating head speed

16 TOOTH PINION = 12.75
18 TOOTH PINION = 11.33
19 TOOTH PINION = 10.74
20 TOOTH PINION = 10.20
21 TOOTH PINION = 9.71
22 TOOTH PINION = 9.27
23 TOOTH PINION = 8.87
24 TOOTH PINION = 8.50
26 TOOTH PINION = 7.85


ESC installation (heli jive 120)

NOTE: Sideplate on heli must come off - or stall build untill ESC is mounted if mounting Heli Jive with pre-installed heatsink.

Best practice for ESC mounting: use heat-sink compound or heat-sink tape
and heat rated tie-wraps and don't use Jive with pre-installed heat sink,
Clean and simple.

thermal tape resource:

http://www.frozencpu.com/products/37..._148_0012.html


Kontronics Esc…

· Heli jive 120 + (+ means more output with cooling)

· Latest version is 11.0

· KSA mode not used with scorpion motor

· Mode 8 updated to work with V-bar external governor

Disconnet red power lead (patch cable between esc and v-bar) if using a separate external BEC Approved to work with V-bar

· Home page has a support and news tab – both are useful

· Newer programming disk – available if needed

· Bail out funct. used with throttle hold set at 40% with full resume for 15 sec.

Heli Jive notes regarding Scorp. 4525-520 ultimate
stick to mode 4 or 5
21 tooth pulley if you want headspeeds of 2200+
20 tooth pulley if you want headspeeds 2000-2200.
The H-jive works best with throttle between 65 and 70,
The H-Jive sweetspot is 65-70 it says so clearly in the manual
Decrease pulley to 20 tooth will bring your throttle up to around 58-72. Much less work for all the electronics and better results

Goblin say to run first flights at 1700-1800 for breaking in gears.

Sidenote: If you are flying at low rpm (less than about 2000/2100 rpm) it is always recommended to use the tail pulley with 26 teeth.


Mikado V-Bar

· full size 5.2– (blue) – more resistant to vibration than the black one

· Requires 2 spectrum satellite receivers

· Small emergency battery suggested (5 cell NiCd/NiHM 8v) charges off BEC

· Pro software upgrade (after purchase – later on)

· Western Robotics is about to release an adapter that will allow their super bec to work with emergency battery pack to power Vbar and servos.

Mikado and Kontronics have partnered togather to allow programing
VBAR v5.2 and heli jive v11.0 setup to be very straight forward - yea!


Wiring diagram (my general scheme)




Landing Skids Modifications:

Rubber trim application:

Skid project details at the the following thread.

https://www.helifreak.com/showthread.php?t=400609

Build thread short-cut

Thunder fighter did such a great job, I didn't want all his valuable work to get lost in the archives of post dated threads. - Check out his build procedure below...

https://www.helifreak.com/showthread.php?t=391487

[amitt]

Originally Posted by windwizard

Thanks for the input - and correction ( 4525 -520 is correct)

(SEE BELOW) can no longer edit above post - must repost.

Wiz

thats great, cause i thought the ultimate wouldnt fit. its on its way from HK, just placed ordered.

[JTAnimal]

Where did you get the trim for the landing gear?

[windwizard]

Originally Posted by JTAnimal

Where did you get the trim for the landing gear?

https://www.helifreak.com/showthread.php?t=400609

WIZ

[OICU812]

When you mention tr limits in vbar you do not mention tr ball distance and tr servo used so that info should be inserted as a suggestion.

Also for those that can't measure angle, state what distance from edge of slider brass bushing to outer bearing edge "boom side", as well from slide tube bushing to tail rotor hub "tr hub side"

[Patrick Senjay]

Where can i get the 5/16 grommets for the canopy?

[fstclyz]

Originally Posted by Patrick Senjay

Where can i get the 5/16 grommets for the canopy?

Got mine at a local hardware store. I bet Ace has them. Great mod.

[SKYQUEST]

Hey Wiz!

What happened to the suggested waxy stuff to break in the maingear? wd-40 is gona be a mess.

This stuff:
http://www3.towerhobbies.com/cgi-bin...?&I=LXATCH&P=7

Still ok to use, or have you found an issue where-as it isnt such a good idea.
(Sux that you cant just keep editing the 1st thread, huh?...dont get HF sometimes...)

[gww528]

Put some WD-40 on a Q-tip and wipe it on the Pinion. Run a couple of flights and wipe it on again a second time... and that should do it. Not messy at all.

[desertstalker]

Originally Posted by SKYQUEST

Hey Wiz!

What happened to the suggested waxy stuff to break in the maingear? wd-40 is gona be a mess.

Follow the manufacturer instructions, some people used other lubricant and it mixed with the powder from the gear and ground their pinion down. Just clean the black powder off every few flights until it beds in.

[windwizard]

Originally Posted by Patrick Senjay

Where can i get the 5/16 grommets for the canopy?

Hi there


I found the ones that I used at Oriely's auto parts store. Had to buy an assorted pack.


Wiz

[windwizard]

Originally Posted by SKYQUEST

Hey Wiz!

What happened to the suggested waxy stuff to break in the maingear? wd-40 is gona be a mess.

This stuff:
http://www3.towerhobbies.com/cgi-bin...?&I=LXATCH&P=7

Still ok to use, or have you found an issue where-as it isnt such a good idea.
(Sux that you cant just keep editing the 1st thread, huh?...dont get HF sometimes...)

+1 on the editing issue - Im goning to repost simpley for that very purpose, to make ongoing updates and edits.


Here is a link to the latest discussion on mainbear breakin issues, I got spooked about suggesting anything diffrent than the recommended WD40 after reading the
report of someone wearing their gear down to the point of replacement in only a few flights due to not using WD40.

I like what you show in your link for other applications, especially on the gears on my smaller 450's.

https://www.helifreak.com/showthread.php?t=402019


thanks for the feedback


Wiz

[windwizard]

UPDATED: PROJECT & BUILD "ISSUES" DATA BASE

SETUP DETAILS

Flight Style: Sport, Big Air n/a
Headspeed: 2094 power / 2178 general /2241cruising
Motor: Scorpion 4525-520 (92.8 % eff.) .......................................... $349.99
Motor lube Scorpion Motor Bearing Lubrication Kit..................... $5.00
Pulley: 21 Tooth (optional Pulley = 9.71:1).................................... $16.00
FBL System: V-BAR Full size (blue) ver. - 5.2................................ $319.99
Hyperion phase sensor............................................ ...................... $9.00
Governor: v-bar

BEC: Western Robotics Hercules Super BEC................................. $100.00
Bec Adaptor (WR) Used for back-up battery pack.......................... $12.00
RX: (2 remotes) Spektrum DSMX Remote Receivers...................... $70.00
BEC Backup Pack: 800 mAh NiMH buffer pack & charger.............. $30.00
ESC: KONTRONICS Heli Jive 120+ HV(v11)..................................... $539.99
Kontronik Pro-disk Programming Card.......................................... $128.00
Cyclic Servos: Outrage BL9180 (8.4v)............................................ .. $380.00
Tail Servo: Outrage BL9188 (8.4v)............................................ ...... $138.00
Futaba replacement arms for Outrage servos # 04021..................... $17.00
(arms replaced due to tight fit next to servo support frame)

Servo Extension Tail servo............................................. ................. $2.00
Main Blades: 690mm Stock SAB n/a
Tail Blades: 115mm Stock SAB n/a
Lipos: 2nd choice Turnigy 35C 6S 5000mah(x2)................................ $120.00
Wire red 10 guage .................................................. ......................... $4.00
Wire black 10 guage............................................. ............................ $4.00
EC5 connectors For Battery Harness (4 set)....................................... $6.00
EC3 connectorsFor BEC (2set)............................................ ............... $2.50
M2.5x10 Screws (1bag)............................................ ......................... $4.00
(longer screws needed for mounting Torq servos)

Shrink tube (green)........................................... ............................... $15.00
Tri Flow synthetic grease with teflon............................................ ... $10.00
Glue gun............................................... ........................................... $9.00
Shoo Goo............................................... .......................................... $6.00
Swashplate leveler (true-blood for trex 700 nitro)............................ $25.00
SAB GOBLIN 700 Flybarless Electric Helicopter Kit.......................... $1000.00
MISC. COST FOR EXTRAS AND SHIPPING TAX................................ $75.00
___________
TOTAL $3422.00

__________________________________________________ _____________________________


Goblin "build issues" data-base.

HEADSPEED CALCULATIONS: (Calculator at readyheli.com)

http://www.readyheli.com/headspeed-calculator.html

Includes the update/repair for the wrong gear ratios (listed in the 1.3V manual) showing the pinion drive gear having 19 teeth not the actual 20.

Example for a Scorpion 4525-520 motor



Result for calculation using 21 tooth (OPTIONAL) motor pulley

• (will keep rpm above head wobble zone)
• Estimated lowest voltage during flight: 42.00
• Lowest RPM (due to voltage and efficiency) : 2023
• For + performance, keep req. RPM below: 2094
• For target performance, keep req. RPM below: 2178
• For - performance, keep req. RPM below: 2241
• 21t = 9.71:1 gear ratio for headspeed calc.

Tech notes:



"Tips and tricks" video threads in SAB Forum cover...

• belt tensioning
• blade grip arm assembly
• gluing bolt to main gear for easy assembly

ALSO - See Mr Mels vbar video series in Mikado support area of Tech Forum

• Longer metal bolts needed for Outrage Torq servo mounting Replacing the M2.5x8 screws with M2.5x10 screws
• Servo extension needed for tail servo safety break away
• Glue gun needed to glue servo cable to inner boom and elec. componant connectors to be secured to Vbar recepticles

Frame issues

Manual 1.3 - page 26 recommends de-burring the edges of the carbon frame but this should be done as the "first order of business" not after the heli is almost fully assembled. All the CF frame pieces are extemely sharp and should be dulled - it is an easy job if completed prior to assembly.


Motor issues

The motor shaft should be cut - required length is 28.5mm

If not cut, the maximum height of the battery is 50 mm

If you cut, then maximum Battery height is 60mm

Maximum motor height is 68mm.

For greater motor height it's necessary to modify the opening in the canopy.

SAB GOBLIN USA - Says..."Quantum 4530 is delta wound and there is no issue using Kontronik Jive ESC with it."

Align MX 700 is perfectly compatible

Scoprion 4035-560 is listed as a motor suitable for general flight in the Goblin
manual p28. but the mounting holes dont line up for all four screws and you will have to mount motor with only two screws! (patern is 30mm spacing)

Scorpion 4525-520 Ultimate - mounting pattern matches the 4 bolt motor plate

Warning! check resistance from shaft to motor leads - should be infinite ohms. If not, the mounting screws could be to long touching motor windings, this could cause ESC FIRE and failure in flight (This issue is a general warning not specific to the Goblin)


Rotor-Head Assembly

Tech note from SAB - "Use the special washer(s), page 23, if you planning to run over 2000 HS (washer is circled on page 15 of manual 1.3)

The head is already assembled without the H232 part. (only for early kits)
If the headspeed is > 2000 rpm then the H232 part has to be added (pag 33).

In any case the blades have to be really tight (pag 33) and a small quantity of gear lube has to be added to the main gear.

These shims increase the damper preload therefore increasing head rigidity. Please make sure your main blades are tight on the grips, you should be able to violently jerk the head in both directions and the blades should not fold.

Failure to tighten the blades properly and/or run incorrect dampening preload can result in a boom strike.

If you remove the shims on the head you won't have any wobble issues at low headspeeds. Wobble present at 1900 rpm."

All later shipments of Goblins (after 1st batch) already have shims installed!


Thrust bearings

Some are reporting that the Thrust bearing is bone dry, others reported bearing installed backwards.

Note: You must disassemble factory head to make sure everything is greased and loctite is applied properly.

SAB is recommending Tri-Flow clear synthetic (PTFE, Teflon) grease for thrust bearing/bearings . You should be able to get this at any bicycle shop.


Mainshaft

Vertical play in the mainshaft occuring due to factory hole being larger than retaining bolt that attaches collet to shaft.

This was by design to allow collet to be position to "take up" any axial/vertical slack in mainshaft but the problem is that it also allows the collet to work its way down the shaft over time.

One solution mentioned...
Use align .5mm trex 700 main shaft washer in between collet and bearing, this will permanently fix it so that you need not relying on a friction fit of collet to hold the assembly in place.

http://www.helipross.com/align-t-rex...er-hn7075.html


Drive Pulley WARNING (ALL 3 pulleys possibly)

SAB Goblin 700 Service Advisory #2 (20th March 2012)
Despite extensive testing, it has come to our attention that one or two main drive pulleys (H0016) have had the pulley flange loosen from the pulley during flight.

We are working to rectify this problem, and have designed a new system to secure the flange to this pulley. Replacement pulleys will be shipping soon – if you have purchased a Goblin, please contact your dealer to arrange a replacement.

Others are now reporting crashes due to this problem and the same problem being found on the motor pulley and tail pully.

DEFECTIVE DRIVE PULLEY REPLACEMENT FROM S.A.B.


37 Tooth [H0101-S]


36T (light weight version with larger inside flange)





NOTE: Replacement tail drive pulleys H0101-S has an extra tooth from origional. Was 36, now 37, for added tail authority.

But replacement tail drive pulley H0016 retains the origional 36 tooth count.


PULLEY SHAFT (Z60)

Z60 pulley shaft must have a little up & down play in the range of 0.2-0.8 mm , confirmed by SAB Tech Dept


Jesus Bolt failure

"Advisory notice to all, the "Jesus" bolt on the secondary shaft. (The upper one above the slanted pinion Z20) failed in flight on my Goblin.

...I have replaced all these with Align 500 head bolts . The bolt that holds the 500 head to the main shaft. It's a perfect fit and has shoulder the whole way through the pinion gear, it works perfect - will not break."


Drive Shaft Bolts - WARNING

There have been reports of bolt failures of those being used to secure
the pinion and pulleys.

SAB has announced on their website (4-10-12)..." We will replace all the bolts
and send to distributors in about a week. New kits will have new
shouldered bolts. All of our bolts are DIN 12.9, highest quality bolts and screws.

Alternative resource for shouldered bolts if your cannot wait for SAB

http://www.alignrcusa.com/index.php?...oducts_id=2385


One Way bearing

"...Brass surrounding one way seized on intermediate shaft.
Took it apart and sanded/cleaned and oiled, all good now.
Another post - "one way" was dry as a sun baked bone, needed grease."

The One Way Bearing should be greased during build!



Tensioning Spring - (tail drive and main drive)

Tail belt tensioning spring was not symmetrical, the length of the bends on the end were different. The short end goes up and the other end goes down, (the shorter side on the support, the longer on the arm.) Sab will update the manual as soon as possible.

Spring issue is related to its orientation - needs to be clarified in the instructions manual. Also, spring may need a dab of epoxy to stay put in mounting hole.

Drive Belt Tensioning Spring - Also could use a tiny dab of epoxy to glue the Drive Belt tensioning springs into the motor mount, - it just makes mounting the motor unit that much easier.


Drive Belt Life?

Depends on the type of flight ...average is over 100 flights
Belt care - (main and tail)... food grade silicon spray to lubricate belts.


Batteries

Use Velcro to help hold batteries in tray – (back of tray is open)

Battery Tray can be installed in one of two positions to allow for slightly
larger batteries if necessary.


Canopy tips

May have to ream out mounting holes to make them line up correctly

Use the foam pieces pushed out from the blade holder to make the canopy fit without sliding to one side. Measure and cut two pieces off with the rounded sides glued to the canopy.

Duct tape inside of canopy over mounting holes to strengthen
canopy from cracking when flexing during removal and mounting

Canopy modification to minimize stress damage: (install 5/16 gromets)

Had to ream out the canopie holes just a bit. With the new gromets mounted on the canopy they slipped over the face of the mounting studs and push into position with a little finger pressure. You still get 2 3/4 turns on the threaded fasteners as they thread tight against the gromets.

One detail - you need to ream the holes in the canopy large enough to allow the gromets to expand just a little bit for when you push them into position over the top portion of the mounting studs.

..





Canopy placement and removal tip

Always put the swash all the way down. Grip links facing front and back. Very easy to slide on the canopy that way - otherwise it can be a real fight!


Boom paint

Some booms needed to be sprayed by local body shop with
a 2 pass clear coat.

I buffed with a polymer treatment product to make the matt finish
shine like it was clear coated


Flybar sensor position

A FBL sensor does not need to be centred on the heli, it just needs to be square to the mainshaft and centerline of the heli. it is important that leads has some flex in it so as to not transfer any vibrations into the sensor.


Swashplate quality

Swash has a little vertical float to the centern ball. Turns out that
“I2 Swashes” are built with the same loose ball and are very good
swashes - should not be an issue.


Main-gear fit and finish

File the plastic away that overlaps the hole in the main gear, makes for a perfect fit on the main shaft.


Tailboom Warning

Check clearance between the blade at "0 pitch" and top of boom.
Min. distance is 145 cm, if less, - add tape under nylon bolts.

FAILURE to rectify this issue may allow for a boom strike!!

https://www.helifreak.com/showthread.php?t=395680

Shoo goo the servo lead (servo inside the boom) down and tape lead to servo, (glue gun application are already being reported to not stick long term to the
inside of the boom)

Chamber the edges of the aluminum block with a small flat file,
so that the plastic bolt heads can easily line up and slide in.

WARNING! Don't over tighten your nylon tail mounting bolts or they will snap!

Quote ..."I snapped one off with the supplied wrench! Just get it snug,
the carbon plate on top will hold it in place,"

Home Depot sells nylon bolts that fit perfectly in case SAB nylon bolts snap.


Boom spacer - Failure

Don't overtighten, and may want to consider not using CA but rather use epoxy
..."I expoxied that sucker to the side of the boom. CA is worthless on metal"


Ball link issues

Blank side of the ball link is pressed onto the ball- SAB stamp faces out.
Ball links are tight, will have to wear in- if too tight then ream them out


Servo installation and related issues

Servos for swash must be installed using spacers provided (For Mikado and
Outrage servos (rubber and carbon fiber) this will require 2.5mmx10mm screws

Servo arms with Torqs servos need to be replaced with mikado or Futabas - both work perfectly on my Torque 9180s.

..."I got the proper resolution from my Vbar and also the arm spacing put the links as vertical as I could measure them. The red also matched the servo color (futaba arms). part numbers liste on first post."


Tail set up issues

Tail rotor stalling due to over inducing pitch -…We reduced the travel to 20 deg Left and 30 deg right, which resulted in a more even VBar setting of 76 and 74.

Please note that the tail servo endpoints are at 76 and 74 and as this is below what Mikado recommends, it still works perfectly. One cannot get the servo arm shorter due to the fixed position of the push rod guide and any shorter on the servo arm results in a push rod that binds in the guide.

General consensus is to add pitch mechanically 3 or 4 deg. (for hover) and set servos centered and pitch arms at 90 for the rest of v-bar setup.

There is a slight amount of radial play in the tail grips because of the thrust bearings

Tail thrust bearing (factory assembled) -dry as a bone without grease - must disassemble factory tail to make sure all is greased and that loctite is applied properly.

...Logo 600 CF tail control rod is longer than stock goblin rod and can be used to make a precision cut and fitted rod, (should be long enough to allow the servo to be turned 180 to allow servo cable to be positioned more accurately away from the tail belt as well)

Flanged bearings - Check the flanged bearings (HC414-S) in your tail side plate / fin! They came loose in some machines and made a strange noise. A little bit of CA and everything was ok,


Main Gear Break-in (forum opinions)

Manual specs...
"A lite lubricant such as WD-40 is recommended for break-in to allow gears to seat properly since there is no lash spacing on the goblin."

A more effective lubricant will only prolong the break-in period. (Normally 5- 10 flights)

WARNING: concerningn main-gear break-in.
From experience: (as stated on the forum)

"I did not use WD-40 as recommended by SAB. Instead I used triflow synthetic grease --> big mistake. The grease + black gear powder (from initial wearing) + dirt gummed up and together this combination somehow has worn the gear so quickly that after 10 flights, I already have tons of backlash which is definitely NOT good.

Replaced the maingear with a new one and used WD-40 for BREAK-IN --> great success. After a few flights, WD-40 flew away and the gear backlash has been perfect!"



GEAR RATIO ERROR IN MANUAL 1.3 – REVISION BELOW

In the manual, the helical pinion (up top) is a 19 tooth gear, but in reality it is 20 tooth

Corrected ratios for calculating head speed

16 TOOTH PINION = 12.75
18 TOOTH PINION = 11.33
19 TOOTH PINION = 10.74
20 TOOTH PINION = 10.20
21 TOOTH PINION = 9.71
22 TOOTH PINION = 9.27
23 TOOTH PINION = 8.87
24 TOOTH PINION = 8.50
26 TOOTH PINION = 7.85


ESC installation (heli jive 120)

NOTE: Sideplate on heli must come off - or stall build untill ESC is mounted if mounting Heli Jive with pre-installed heatsink.

Best practice for ESC mounting: use heat-sink compound or heat-sink tape
and heat rated tie-wraps and don't use Jive with pre-installed heat sink,
Clean and simple.

thermal tape resource:

http://www.frozencpu.com/products/37..._148_0012.html


Kontronics Esc…

· Heli jive 120 + (+ means more output with cooling)

· Latest version is 11.0

· KSA mode not used with scorpion motor

· Mode 8 updated to work with V-bar external governor

Disconnet red power lead (patch cable between esc and v-bar) if using a separate external BEC Approved to work with V-bar

· Home page has a support and news tab – both are useful

· Newer programming disk – available if needed

· Bail out funct. used with throttle hold set at 40% with full resume for 15 sec.

Heli Jive notes regarding Scorp. 4525-520 ultimate
stick to mode 4 or 5
21 tooth pulley if you want headspeeds of 2200+
20 tooth pulley if you want headspeeds 2000-2200.
The H-jive works best with throttle between 65 and 70,
The H-Jive sweetspot is 65-70 it says so clearly in the manual
Decrease pulley to 20 tooth will bring your throttle up to around 58-72. Much less work for all the electronics and better results

Goblin say to run first flights at 1700-1800 for breaking in gears.

Sidenote: If you are flying at low rpm (less than about 2000/2100 rpm) it is always recommended to use the tail pulley with 26 teeth.


Mikado V-Bar

· full size 5.2– (blue) – more resistant to vibration than the black one

· Requires 2 spectrum satellite receivers

· Small emergency battery suggested (5 cell NiCd/NiHM 8v) charges off BEC

· Pro software upgrade (after purchase – later on)

· Western Robotics is about to release an adapter that will allow their super bec to work with emergency battery pack to power Vbar and servos.

Mikado and Kontronics have partnered togather to allow programing
VBAR v5.2 and heli jive v11.0 setup to be very straight forward - yea!


Wiring diagram (my general scheme)




Landing Skids Modifications:

Rubber trim application:

Skid project details at the the following thread.

https://www.helifreak.com/showthread.php?t=400609

Build thread short-cut

Thunder fighter did such a great job, I didn't want all his valuable work to get lost in the archives of post dated threads. - Check out his build procedure below...

https://www.helifreak.com/showthread.php?t=391487

[Patrick Senjay]

Originally Posted by windwizard

Hi there


I found the ones that I used at Oriely's auto parts store. Had to buy an assorted pack.


Wiz

Is 5mm by 16mm size? I`m a bit blond. LOL

[Luisito]

I believe there's a typo on the tail drive pulley tooth count. Shouldn't it be 26 and 27, not 36 and 37?

"NOTE: Some replacement tail drive pulleys have an extra tooth from origional. Was 36, now 37, for added tail authority. But not the one pictured on the left - for sure."

Luis

[gww528]

Originally Posted by windwizard

Canopy tips

May have to ream out mounting holes to make them line up correctly

Use the foam pieces pushed out from the blade holder to make the canopy fit without sliding to one side. Measure and cut two pieces off with the rounded sides glued to the canopy.

Duct tape inside of canopy over mounting holes to strengthen
canopy from cracking when flexing during removal and mounting

Did the the Canopy Tip... removed the "o-ring" on the canopy nut, it seats better with the grommet. It also screws on a little better. Thx

[gww528]

Originally Posted by Luisito

I believe there's a typo on the tail drive pulley tooth count. Shouldn't it be 26 and 27, not 36 and 37?

"NOTE: Some replacement tail drive pulleys have an extra tooth from origional. Was 36, now 37, for added tail authority. But not the one pictured on the left - for sure."

Luis

The wording is confusing.

The tail DRIVE pulley was 36 and now the new ones are 37T (with screws) & 36T (light weight version with larger inside flange)


37 Tooth [H0101-S]


36T (light weight version with larger inside flange)


-------------------------------------------------------

The Tail Pulleys are 26T [H0103-S] & 27T [H0102-S]. (not the DRIVE tail pulleys)

[windwizard]

The wording is confusing... Your right, I'll fix that.


And the way you explained it is correct.


Wiz

[windwizard]

Is 5mm by 16mm size? I`m a bit blond. LOL

5/16 is a measurement in inches,

That is to say, it is specifying that the diameter of the inner hole is 5/16 of one inch.


Wiz

[windwizard]

Thank you for the feedback guys - I'll make corrections as needed.


Wiz