RunRyder RC
 3  Topic Subscribe
WATCH
 1 page 1083 views
HelicopterBergen R/C Helicopters › Making the EB lighter?
11-28-2005 07:12 PM  12 years agoPost 1
iflybyu77

rrKey Veteran

Fort Wayne, IN

My Posts: All  Forum  Topic

I have sat around here looking at the EB lately and am kind of annoyed by having to add nearly a pound of ballast to the nose. Not only is it wasted weight and space, but it also stresses the radio tray. So how do I fix this problem?

I know that the EB's boom and tail rotor gearbox is "well built" but does it need to be this heavy? Anyone who owns an EB knows that if you pull the boom off the heli and hold just that at the end of the boom knows that this thing is heavy.

Is there a way to fit a carbon boom on this thing? Anyone make something in the size that the EB would need? Or maybe there is a lighter aluminum boom? For my applications, I don't need to worry about the rigors of 3d, so I can sacrifice some ridgity. Also, is there a better way to lighten the gearbox up? I would think with just these two items, and even making the fins "3d" style (which I already did myself) would possibly eliminate the need for the ballast. And for a user such as myself who needs the ship to be light because of the loads that it must carry, it would be a great help.

Ya ya, I know, it's a gasser. It can pick up an extra pound or two, but I'm pushing the limits already, so anything I can do to reduce the weight is fine with me.

Other ideas?

PM  EMAIL  HOMEPAGE  GALLERY  Attn:RR  Quote
11-28-2005 07:51 PM  12 years agoPost 2
Crazy Horse

rrApprentice

Orlando FL

My Posts: All  Forum  Topic

it would suck giving up that nice beefy tail gear box but I have seen where a chap fitted a MA extreme tail gear box to his bergy....not sure who it was.

sponsored by generous people that give tips to thier limo driver

PM  EMAIL  HOMEPAGE  GALLERY  Attn:RR  Quote
11-28-2005 08:55 PM  12 years agoPost 3
Chris Bergen

rrElite Veteran

cassopolis, MI USA

My Posts: All  Forum  Topic

I would be afraid that "lightening" things would sacrifice reliabilty and strength. A carbon boom WILL flex compared to the Aluminum one, and you will notice it in the holding power of the tail at these reduced RPM's.

You can swap to the "standard" gearbox, which may save an ounce or 2, but you lose the reliability of the 1" gears in the HD box.

If you need more payload, try the Twin. If you're going beyond the capability of the helicopter, you're stressing the drivetrain, framework, and engine.

You wouldn't pull a fifth wheel with a Honda Accord, would you?

Chris D. Bergen

PM  EMAIL  GALLERY  Attn:RR  Quote
11-28-2005 09:09 PM  12 years agoPost 4
iflybyu77

rrKey Veteran

Fort Wayne, IN

My Posts: All  Forum  Topic

Fifth wheel? Sure! Ever seen that picture of the car with 30 sheets of plywood on the roof? That was me!

Seriously though, for my application Chris, do I really need that much holding power? I'm not doing inverted backwards circuits here! And what about the tail box? For doing what I'm doing, do I need the HD box? And maybe I'm exagerating on loads here - I'm really only picking up >10lbs. And when I say it's on the ragged edge of performance, I'm thinking more like the emergency situations when autorotations are critical or being slightly more maneuverable.

PM  EMAIL  HOMEPAGE  GALLERY  Attn:RR  Quote
11-28-2005 09:14 PM  12 years agoPost 5
Chris Bergen

rrElite Veteran

cassopolis, MI USA

My Posts: All  Forum  Topic

Exactly, Thanks!!

Have you tried an auto with the weight on board? You might be surprised, especially if using V-Blades!!

Maybe you don't need all that power, until you NEED that power!!

Chris D. Bergen

PM  EMAIL  GALLERY  Attn:RR  Quote
11-28-2005 09:20 PM  12 years agoPost 6
iflybyu77

rrKey Veteran

Fort Wayne, IN

My Posts: All  Forum  Topic

Awesome Greg! You read my mind!

I didn't really get an answer on what you think about my application Chris. Do you think I really need that strength in the boom itself? I see a lot of "other" heli's running the 800's and running what at least APPEARS to be a carbon boom and a less rugged looking box. I don't hear any issues with them either. I'm not complaining really, in fact this could be more parts that you could sell as "downgrades" to those looking for lighter heli's. It's definintely a beast as is, just would love to fix the ballast issue.

Oh and for reference, I have a 4 cell sub c pack and a 1800 mah secondary pack up front, and still I have to add more weight..

PM  EMAIL  HOMEPAGE  GALLERY  Attn:RR  Quote
11-28-2005 10:14 PM  12 years agoPost 7
Chris Bergen

rrElite Veteran

cassopolis, MI USA

My Posts: All  Forum  Topic

Barring doing a complete stress analysis like what is done to full size aircraft, we tend to make things stronger than is necessary to keep from getting into that ragged edge of reliability.

We may not always succeed, but we can make changes as needed very quickly. Keep in mind, my father didn't start doing this yesterday. He has a few years of knowledge of what works and what doesn't.


You are more than welcome to change whatever you feel necessary on YOU'RE helicopter. Let us know how it goes.

Chris D. Bergen

PM  EMAIL  GALLERY  Attn:RR  Quote
11-28-2005 10:22 PM  12 years agoPost 8
iflybyu77

rrKey Veteran

Fort Wayne, IN

My Posts: All  Forum  Topic

Aww man!

Anyways, do you know if there is a carbon boom that someone sells that would fit the EB? I have no idea what the boom length is now either. I need to replace mine anyways, so it's just easier if I could do it now...

PM  EMAIL  HOMEPAGE  GALLERY  Attn:RR  Quote
11-28-2005 10:36 PM  12 years agoPost 9
Chris Bergen

rrElite Veteran

cassopolis, MI USA

My Posts: All  Forum  Topic

Oh now you want me to make it easy for you!!

The EB boom is 37" long.

Try Mcmaster Carr, although I doubt you'll find the strength you need. And could be expensiiiiive.

I believe MA has theirs special made with the continuous weave or whatever it's called to get the strength necessary. I could be wrong though.

Chris D. Bergen

PM  EMAIL  GALLERY  Attn:RR  Quote
11-29-2005 07:22 PM  12 years agoPost 10
Tristan Buhler

rrApprentice

SLC, Utah

My Posts: All  Forum  Topic

it would suck giving up that nice beefy tail gear box but I have seen where a chap fitted a MA extreme tail gear box to his bergy....not sure who it was.
I found out Rob Cosby did this to his gasser. Check out his gallery:

http://runryder.com/helicopter/gallery/1240/

If you are worried about that much weight, would it be possible to move you payload forward to balance it out w/o that added weight? I see in your gallery you have a underslung mount. Could you move the gimbal forward for better balance?

Tristan Buhler.

PM  EMAIL  HOMEPAGE  GALLERY  Attn:RR  Quote
11-29-2005 07:36 PM  12 years agoPost 11
iflybyu77

rrKey Veteran

Fort Wayne, IN

My Posts: All  Forum  Topic

The only problem with doing that Tristan is that I use different cameras, and the primary camera mount I use now is still an underslung, but the camera is directly below the main mast. I also need to have the mount slightly hanging to get best results, so it's not really effective to shift it around because then the mount would hang funny, either more towards the front or back. I've thought of putting more of the gear that is on the mount itself onto the heli too, and have it connect to the mount via some sort of umbilical cord, but I have limited space left now up on the radio tray. I'll have to take a look at what you linked to...

PM  EMAIL  HOMEPAGE  GALLERY  Attn:RR  Quote
WATCH
 1 page 1083 views
HelicopterBergen R/C Helicopters › Making the EB lighter?
 Print TOPIC  Make Suggestion 

 3  Topic Subscribe

Monday, December 11 - 12:19 am - Copyright © 2000-2017 RunRyder   EMAILEnable Cookies

Login Here
 New Subscriptions 
 Buddies Online