is it just me or would a goblin make a great base for a scale bird?

[stevec]

Hi Chaps,

Like everyone else in the world with an internet connection I have been looking at the SAB Goblin, but I was thinking the compact drivetrain and servo layout would make it ideal for a scale bird.

something like a jetranger or a Huey would be great as the mechanics would fit where they go in a real heli leaving the cabin area free for you to go to town...

what do you think?



Cheers
Steve

[CeeveeSiN]

Originally Posted by stevec

Hi Chaps,

Like everyone else in the world with an internet connection I have been looking at the SAB Goblin, but I was thinking the compact drivetrain and servo layout would make it ideal for a scale bird.

something like a jetranger or a Huey would be great as the mechanics would fit where they go in a real heli leaving the cabin area free for you to go to town...

what do you think?



Cheers
Steve

You may be on to something there.. yeh the mechanics are very small an compact and self contained.. that would give you a neat platform.. the tail might be a challenge though..

[stevec]

I am sure a belt could be made that would fit, or do a converter to torque tube then you can make it whatever length you like... I don't do big electrics but I'd definitely consider using these mechanics if I was in the market for a big electric scale bird. you could get away with a much smaller motor or swing much bigger blades as you wouldn't need the aggressive head speed that it gives you.

I'm just looking on the fast lad website for the price of spares it would be expensive but a nice neat way to do it... maybe when the small one comes out. I wonder if they are going to do a 500 size one eventually.. that would be cool.

[CeeveeSiN]

Originally Posted by stevec

I am sure a belt could be made that would fit, or do a converter to torque tube then you can make it whatever length you like... I don't do big electrics but I'd definitely consider using these mechanics if I was in the market for a big electric scale bird. you could get away with a much smaller motor or swing much bigger blades as you wouldn't need the aggressive head speed that it gives you.

I'm just looking on the fast lad website for the price of spares it would be expensive but a nice neat way to do it... maybe when the small one comes out. I wonder if they are going to do a 500 size one eventually.. that would be cool.

yes a 500 size is already on the confirmed list

[Cap231ex]

Yes it would and with its so many different tail ratios available you could slow your headspeed down to a crawl.

I've been waiting to see someone try it , I just don't know how one would work out the tailboom mounting as it really doesn't use a tailboom tube.

[CDRKrotchetyUSN]

I've been looking at my 700 with sinister thoughts...
The power train and mechanics would lend themselves very nicely to a HH60-H (Navy Strikehawk).

[MD500]

Make it happen brother! Gives us other excuse to buy another heli hell yes......

[Keyrigger]

It is already being done with the 700 and is offered by East Coast Vario. It is a custom set of mechanics using parts from SAB and the 500 is the next one on the block. Don't expect bargains with this system but expect the best quality you can find, period. The results are already in the air with a few models and more will come out as time goes on. The idea was to get the mechanics up in the doghouse of the larger machines out there so the 700 size will be doing duty in 1//6th scale and larger models. I would think that a 500 size set of mechanics for the doghouse could work in something along the lines of the 600/700 size models that are smaller than 1/6th scale. They look like a well made watch. Take care.

Don

[Arcturus97]

HeliDirect posted this on their Facebook page a few days ago: a video with a Goblin 700 based EC-145 from SEFF

https://www.facebook.com/photo.php?v...type=2&theater

[Cap231ex]

Yeah it has been available for some time now from http://www.eastcoastvario.com/

[dragonflyhkg]

Hmmm; well, now I'm confused.

I sent an email message to East Coast Scale Helicopters enquiring about the Goblin based mechanics. My project is to be a 600 or 700-size scale bird.

I received a reply from JH;
"The Goblin based mechanics we have are intended for larger models. They will not work on 600-700 size."

The reply I received from JH seems to indicate that I'll be going it alone with stock Goblin mechanics and my own solution.

Is anyone using this Goblin based mechanics set, and if so, what's the issue with size here?

M

[treotraveler]

Originally Posted by dragonflyhkg

Hmmm; well, now I'm confused.

I sent an email message to East Coast Scale Helicopters enquiring about the Goblin based mechanics. My project is to be a 600 or 700-size scale bird.

I received a reply from JH;
"The Goblin based mechanics we have are intended for larger models. They will not work on 600-700 size."

The reply I received from JH seems to indicate that I'll be going it alone with stock Goblin mechanics and my own solution.

Is anyone using this Goblin based mechanics set, and if so, what's the issue with size here?

M

The problem with size is, the 600 size fuselage is too small to fit that goblin style mechanics up in the dog house. The 700 size fuselage is a little bigger in the dog house, but not much bigger.

You should consider 800 size or larger fuselage to fit that goblin style mechanics in the dog house. Then most of it will be custom work to mount the mechanics in the upper area of the fuselage, and modding or building the tail drive to the tail rotor...

[Andy01]

It depends on the model. If it is a model with a "large" doghouse like EC-145 I have seen Goblin mechanics fitted into a RCA EC-145 600 size. In fact, I think (from memory) it was Joe's partner (Peter) in the venture who did it.

The Goblin mechanics are quite wide at the servo level, and so models with narrower doghouses like Jet Ranger, Long Ranger etc are probably too tight. I know Joe advised a guy at our club that they would not fit into a Vario Jet Ranger.

I have made a set for my Baumann EC-145 and they just "disappear" into the fuselage, but it is a BIG fuselage - 1750mm long, 800-850mm blades, and the doghouse is very spacious.

I think Joe's website gave full dimensions for the mechanics with servos fitted, so you could probably research the width of the doghouse on your chosen model.

Be paitent though - I bought my own Goblin parts, and I have been waiting for a couple of months for Joe to ship the tail drive adapter, which he did yesterday. He offers a step down for "low" tail models (eg Blackhawk) and a step-up tail for EC-145, EC135 etc. From what Joe and Peter told me the adapters have not been selling well at all, so I don't think he stocks them, and mine was made to order.

Colin

[dragonflyhkg]

Gents,

Thanks for the replies.

In my case, the subject model is the A/MH-6M (MD500). Looking at the images of the mechanics set and referring to the aircraft itself, the intended installation is really at the top of the cabin and not projected into the doghouse. Such an installation would leave the cockpit forward of the front bulkhead clear. Between the forward cabin bulkhead and the aft cabin bulkhead, the mechanics would project downward through the upper third of the cabin. That would be entirely acceptable, still allowing enough scale detail to effectively obscure the mechanics.

I have not found any dimensional information on the website for the Goblin based mechanics set. With some dimensions, I could at least "scale" the images and derive the required information.

Any clues?

I'll contact JH again.

M

[dragonflyhkg]

Gents,

Found it; the "Goblin Information" page has the dimensioned photographs!

For information I've just discovered an issue with IE11, not showing images embedded in web pages until I reset some privacy settings!

Anyway, there's enough there to get going on this.

M

[Andy01]

I may be proven wrong, but I suspect that the only way you would get Goblin mechanics into a 600 sized 500 is by mounting the mechanics much lower and using a longer shaft with long links from servos to swash.

Looking at the pics I would be fairly certain that the doghouse would not be wide enough, but it may take the swashplate. This might defeat the purpose a bit though as the mechanics would probably sit about 100mm down into the cabin.

Colin

[dragonflyhkg]

Colin, Gents,

I agree with your assessment Colin.

The limiting factor for a mounting against the cabin roof is the curvature of the roof itself. I'd have to lower the mounting to get the servos to just clear the roof at the widest point from the centreline of the mechanics.

It's a question of how far below the cabin roof the mechanics set is mounted and thus a longer main shaft and swash-plate linkages.

The Roban Compactor drives would require the same approach to task. I note that on the Roban 700-size MD500E, the website photographs show the motor protruding above the cabin into the front of the doghouse, at the location where the main shaft should be for a scale solution.

Despite the obvious CofG issue, a compact mechanics set with the motor aft of the main shaft would be good use of the doghouse and a fine scale solution.

Food for thought.

M

[mrultralite]

What about the new "mostro"?

[dragonflyhkg]

Yes, the Mostro by Avant is a possibility, however, like the SAB Goblin, the motor is in front of the rotor mast and the range of motors that suit the mechanics are often at the same level as the swash plate. This means that for many scale subjects the motor must protrude above the fuselage in front of the dog house.

One real possibility are the E550 and E620 series from Thunder Tiger. The motor is mounted behind the rotor mast, and may protrude above the cabin roof into the dog house at that location. It becomes a question of relocating the tail rotor servo to a rear location and ensuring that the basic three swash plate servos remain below the cabin roof and not project into the forward cockpit area.

M