SDX Setup help please

rrTV-PHOTO GALLERIES MY GALLERY HELP-FAQ

myHOME PM pmRR MEMBERS 275 ONLINE 1 EVENTS SEARCH REGISTER START HERE

WATCH

4 pages [ << < ( 1 ) 2 3 NEXT >> ] 7180 views

Post Reply

RunRyder	RunRyder

Home › ✈️Aircraft › 🚁Helicopter › HIROBO › Hirobo SDX › SDX Setup help please

09-18-2009 09:16 PM 11 years ago

Topic Vote

0Post 1

Andy from Sandy

rrElite Veteran

MyPosts All Forum Topic

SDX Setup help please

I have just completed the build of my SDX. It has gone together really quickly and easily. I have used the 135 degree settings

I am using BLS451 servos.

I have set the lengths of the rods from the levers up to the swash as per the manual and have adjusted the lengths of the rods from the levers to the servo horns whilst I had the pins inserted and the servos at 50%. The swash looks spot on. I first off set the swash afr all to 50%. The radius block hits the bottom of the head block so I reduced the pitch afr until it didn't. I put the blades on for a quick check of pitch range and I got something over -15 and not 0 at midstick. I adjusted the pitch rod lengths until I have 0 at mid stick. I am now getting about -13 to +12. The aileron and elevator seems to be way to much so I reduced the afrs until I think it is all okay but I have had to reduce them to 36%. Now I only have about 5 or 6 degrees of cyclic pitch. I have not made any adjustments to any of the other rods.

Not that I want it but I read that I should have more pitch and certainly more cyclic pitch than I have at present.

What is going to be the easiest way to set the model up to centralise the pitch range and get the cyclic pitch ranges please?

Should the washout arms be parallel at mid stick and perpendicular to the mast at midstick?

EDIT: The pitch AFR is at 43% and the cyclic AFRs are 36%. The gap in the pitch rod is now nearer 5mm and not the 2.5 called for in the manual.

SHARE PM EMAIL GALLERY Attn:RR Quote

09-18-2009 10:16 PM 11 years ago

0Post 2

S76 Mech

rrElite Veteran

Hatboro, Pa.

MyPosts All Forum Topic

I adjusted the pitch rod lengths until I have 0 at mid stick. I am now getting about -13 to +12.

It sounds like your very close. Adjust your mixing rod (long one) until you have 12/12 or even pitch both sides.

Should the washout arms be parallel at mid stick and perpendicular to the mast at midstick?

yes

Not that I want it but I read that I should have more pitch and certainly more cyclic pitch than I have at present.

The SDX is capable of 30deg total pitch. I can say that you probably won't need more than 12-13deg. Adjust your swash AFRs for Elev/Aile until your cyclic pitch is around 8 degrees, that should do fine for 3D.

The gap in the pitch rod is now nearer 5mm and not the 2.5 called for in the manual.

I just measured mine and they are both at 3.5mm

Hope this helps!Gaui Greatness X7, X5, NX4, X3

SHARE PM EMAIL HOMEPAGE GALLERY Attn:RR Quote

09-18-2009 10:21 PM 11 years ago

0Post 3

S76 Mech

rrElite Veteran

Hatboro, Pa.

MyPosts All Forum Topic

PS: I forgot to mention. I am running 13/13 9 cyclic for Hard 3D. If you plan on an aggressive setup, make sure you do not have any binding in the head. Spin the head while applying pitch and cyclic and see if she binds(the head will slowdown or stop).

Oh yeah, are your balls 15mm from the center screw on the servo horns?Gaui Greatness X7, X5, NX4, X3

SHARE PM EMAIL HOMEPAGE GALLERY Attn:RR Quote

09-18-2009 10:34 PM 11 years ago

0Post 4

Andy from Sandy

rrElite Veteran

MyPosts All Forum Topic

Thanks for the help.

If I increase the elevator afr when at full positive pitch I give full back elevator the radius block moves down the mast. I am only able to set the afr at 36% to stop this. It would appear with the setup as it is I am unable to get any more cyclic pitch.

I have not really started setting yet. This just ten minutes or so of playing after getting all the wiring in tidy.

SHARE PM EMAIL GALLERY Attn:RR Quote

09-18-2009 10:38 PM 11 years ago

0Post 5

doorman

rrProfessor

Sherwood, Arkansas

MyPosts All Forum Topic

💎Sustaining Member

Adjustments!!

Sounds like a lot of adjustments and low values!!!!
Are you sure you are in the proper hole in the ms??? You should be in the higher hole from the bottom... Just a thought!!!!
Stan

AMA 2918-Team Spin Blades,,Castle Creations, Unique Aircraft

SHARE PM EMAIL GALLERY Attn:RR Quote

09-18-2009 10:45 PM 11 years ago

0Post 6

Andy from Sandy

rrElite Veteran

MyPosts All Forum Topic

I have followed the manual for holes and rod lengths. The big bolts in the head block are at 90 degrees to the ones holding the drive gears on.

Rick you have the short pitch rods at 3.5 mm and mine are at 5mm which suggest I have got to adjust something else to increase the positive pitch on the blades.

Also at present it is a suprise to have the radius block hit the head block and not get the 15 degrees as advertised.

SHARE PM EMAIL GALLERY Attn:RR Quote

09-18-2009 11:03 PM 11 years ago

0Post 7

S76 Mech

rrElite Veteran

Hatboro, Pa.

MyPosts All Forum Topic

If I increase the elevator afr when at full positive pitch I give full back elevator the radius block moves down the mast.

I am not sure about the Futaba your using, does it support 140deg CCPM? I do know that my DX7 does not and therefore I have to use a P-Mix to cancel out the unwanted interaction on the elevator (washout moving up/down on the MS)

Rick you have the short pitch rods at 3.5 mm and mine are at 5mm which suggest I have got to adjust something else to increase the positive pitch on the blades.

Try the long mixing rods (out) this should move your pitch range in the positive direction.

And like Stan suggested, double check which hole you are 'in' on the MS. If your in the lower hole, your pitch range will be off about 5 degrees. This might explain why your rod lengths are off from what the manual states.Gaui Greatness X7, X5, NX4, X3

SHARE PM EMAIL HOMEPAGE GALLERY Attn:RR Quote

09-18-2009 11:09 PM 11 years ago

0Post 8

Andy from Sandy

rrElite Veteran

MyPosts All Forum Topic

I am using a 10CG so it has the programming for 135 degree swash.

One thing I am not sure of is step 16 on page 24.

See fig. 1. I did not do this I confess. Does this have any bearing on what might be off? It talks about shortening the stabilizer rod lengths.

I will double check the mast holes.

SHARE PM EMAIL GALLERY Attn:RR Quote

09-19-2009 12:41 AM 11 years ago

0Post 9

doorman

rrProfessor

Sherwood, Arkansas

MyPosts All Forum Topic

💎Sustaining Member

Just Pulled My Manual....

The step that you are talking about on page 24, could be helping to make things difficult.... but it is more of a check for binding....
I just checked my travels and I am at 60 Ail, 60 Ele, 65 Pit
Also all of my rods are within about 1mm of the drawings in the manual...
The 4mm bolts in the head are 90 degrees from the bolts in the main gear... and when I look under the main gear between the bottom of the gear and the top of the lower bearing, I can see the other hole in the ms as I rotate it...My settings are very close to Ricks....
Let us know how it is coming, but I went from the swash up when I did my build... starting with that level at 1/2 stick and then made everything 90 degrees from there on the way up...

Good Luck, Stan

AMA 2918-Team Spin Blades,,Castle Creations, Unique Aircraft

SHARE PM EMAIL GALLERY Attn:RR Quote

09-19-2009 09:33 AM 11 years ago

0Post 10

Andy from Sandy

rrElite Veteran

MyPosts All Forum Topic

Thanks Stan.

SHARE PM EMAIL GALLERY Attn:RR Quote

09-19-2009 11:07 PM 11 years ago

0Post 11

rexxigpilot

rrProfessor

rexxig2@comcast.net

MyPosts All Forum Topic

Also at present it is a suprise to have the radius block hit the head block and not get the 15 degrees as advertised.

Andy,
You won't get ±15° using the B/H mixing arm positions shown in the manual. It even says that on page 21, bottom right corner. The manual positions also cause binding with very little cyclic and approx. ±12° pitch. If you move the ball positions to the middle on each side of the mixing arms you will get all the collective and cyclic throw you need including ±15° collective if you want. I don't since it too easily bogs the head.

Using the middle holes I set my SDX to get ±12° collective and ±9° cyclic (both elevator and aileron) without any binding. With this setup and no weight in the paddles, my SDX is as quick as any heli out there including the Velocity 50.

My 135° swash is set to 43 A, 43 E, 50 P. I backed off on the pitch curves to 75% to get the pitch down to 12°.

As for the centering, I use 3.7mm on the pitch rod (short link) to the flybar seesaw instead of the manual stated length of 2.5mm. I really could make it longer since I have a slight offset of -5% in my pitch curves.

Hope this helps.

SHARE PM EMAIL GALLERY Attn:RR Quote

09-20-2009 12:37 AM 11 years ago

0Post 12

Andy from Sandy

rrElite Veteran

MyPosts All Forum Topic

rexxigpilot, that does help, thank you. At present I cannot get anywhere near 50% on pitch without binding and can only use 36% for A and E. With full negative and full back elevator the anti-rotation pin is at the bottom and cannot go any further. When you say middle holes is this for the long links coming from the swash or for the pitch rod link?

I didn't get much flying done with it today as once up into a hover I could see it had a vibration. I have just had the head to bits and checked the shafts and they are okay so I will take the engine and clutch stack from my Sceadu and put that in.

Have you used red loctite on the feathering shaft? I had to use quite alot of heat to get them undone.

SHARE PM EMAIL GALLERY Attn:RR Quote

09-20-2009 03:24 AM 11 years ago

0Post 13

rexxigpilot

rrProfessor

rexxig2@comcast.net

MyPosts All Forum Topic

When you say middle holes is this for the long links coming from the swash or for the pitch rod link?

Both. See pictures below. The anti-rotation pin goes all the way down but doesn't hit on mine.

Have you used red loctite on the feathering shaft? I had to use quite alot of heat to get them undone.

Used red loctite on the feathering spindle once, never again!

SHARE PM EMAIL GALLERY Attn:RR Quote

09-21-2009 06:22 PM 11 years ago

0Post 14

Andy from Sandy

rrElite Veteran

MyPosts All Forum Topic

rexxigpilot, Thanks for the pictures.

If I move either ball to the middle hole I can get more than enough collective pitch and I think about 7 degrees of cyclic.

With the book settings I get +/-12 collective with 38% pitch AFR and 6 cyclic with 36% AFR. Also the pin is at the bottom of the guide when I have full negative and full back elevator.

I can only have the pitch AFR at 46% max else the radius block hits the head block.

Reading Dr. Bens post however I am losing resolution as the AFR values are quite low.

SHARE PM EMAIL GALLERY Attn:RR Quote

09-26-2009 08:57 PM 11 years ago

0Post 15

Andy from Sandy

rrElite Veteran

MyPosts All Forum Topic

I took the SDX for its maiden flight last weekend and the model had a vibration that was at head speed. Increasing the head speed increased the vibration.

Today after rebuilding the head the model was better but it is still not running right. I swapped engines from my Sceadu. The Sceadu still flys nice so it was not and is not an engine problem.

After a few seconds in the hover a resonance builds up and the skids start to shake. The blades have been checked and flown on the Sceadu and are fine as are the paddles.

I am going to put the Sceadu head on it for a test.

Has anyone got any suggestions as to what might be causing the vibration please?

SHARE PM EMAIL GALLERY Attn:RR Quote

09-26-2009 09:00 PM 11 years ago

0Post 16

TMoore

rrMaster

Cookeville, TN

MyPosts All Forum Topic

Change out the plastic head block.

TMPart 107.
The only ZERO flight hour certificate in the world.
It's like getting a driver's license without the driver's test.

SHARE PM EMAIL HOMEPAGE GALLERY Attn:RR Quote

09-26-2009 09:05 PM 11 years ago

0Post 17

payne1967

rrElite Veteran

MyPosts All Forum Topic

if its the evo head that you'll be putting onto the sdx watch out for the head binding
i ended up shortening the rods to stop it
afer i got the sdx spares the sdx head went back on

SHARE PM EMAIL HOMEPAGE GALLERY Attn:RR Quote

09-26-2009 09:09 PM 11 years ago

0Post 18

Andy from Sandy

rrElite Veteran

MyPosts All Forum Topic

Change out the plastic head block

Would that be for another plastic one or is there a metal part I should consider?

if its the evo head that you'll be putting onto the sdx watch out for the head binding

I have put the evo head on complete with the control rods. It has gone okay and there is no binding with the settings I have. Thanks for the tip.

SHARE PM EMAIL GALLERY Attn:RR Quote

09-26-2009 09:42 PM 11 years ago

0Post 19

payne1967

rrElite Veteran

MyPosts All Forum Topic

if you want metal head parts
sit down
take a sharp breath
and then look at the turbulence parts
if you need part numbers for the turbulence head bit just ask and i'll look in my manual

its good to know the evo head fitted ok
the one i used was second hand main gear upwards and wasn't built by myself
i just stripped it and made sure it was ok to use

SHARE PM EMAIL HOMEPAGE GALLERY Attn:RR Quote

09-26-2009 09:53 PM 11 years ago

0Post 20

Andy from Sandy

rrElite Veteran

MyPosts All Forum Topic

All I did was unclip the rods from the swash and pull the lot off the mast and transplant it onto the mast of the SDX. Reconnected the links, set the radius block and hey presto!!

if you want metal head parts
sit down
take a sharp breath
and then look at the turbulence parts
if you need part numbers for the turbulence head bit just ask and i'll look in my manual

I had a look on rc power supply but could not find the head block, so I would be grateful if you could let me know the part numbers please?

What TM is suggesting is that somehow the plastic head block I have is a bit off causing the problem. I did a test on the balance of the mast without the main blades and it is pretty close. It must be fairly close with the mains on else the model would probably really shake.

SHARE PM EMAIL GALLERY Attn:RR Quote

WATCH

4 pages [ << < ( 1 ) 2 3 NEXT >> ] 7180 views

Post Reply

RunRyder	RunRyder

Home › ✈️Aircraft › 🚁Helicopter › HIROBO › Hirobo SDX › SDX Setup help please

Print TOPIC

10 Topic Subscribe

New Subscriptions

Buddies Online