View Full Version : Fan / Clutch Runout
asong26
09-30-2006, 01:41 AM
Lately I've been reading up a lot about the importance of proper runout. My question is this: Is this runout issues isolated to Predator Gassers only? I know many of you on this particular forum / thread runs the Spectra-G.
I've also heard from the grapvines that on non-Predators, the runout is not an issue, since they are self-aligning... Is this correct?
Thanks.
BTW: My TRM modded engine is on it's way! Let's the build begin!!!
PaulH
09-30-2006, 06:08 AM
You need to dial indicate the fan/hub on all engines, including nitro engines. A lot of people don't bother doing it and then wonder why they have vibration issues.
cbergen
09-30-2006, 10:35 AM
The clutch system on the Bergen Intrepids is called a self aligning system. This means it is not required to dial indicate the CLUTCH onto the fan hub. Basically, you visually align the bottom of the clutch and clutch bell to the top of the fan hub.
It is still necessary to dial indicate the fan hub onto the engine.
asong26
09-30-2006, 02:12 PM
The clutch system on the Bergen Intrepids is called a self aligning system. This means it is not required to dial indicate the CLUTCH onto the fan hub. Basically, you visually align the bottom of the clutch and clutch bell to the top of the fan hub.
It is still necessary to dial indicate the fan hub onto the engine.
Chris,
Thank you for that clarification. You've confirmed what I've heard from the others.
Your helis are awesome! I am so impressed with your turbines!
Rodney
09-30-2006, 08:51 PM
Takes some time but you will need to make sure you get that fan on that P Gasser straight and very little run out.
asong26
09-30-2006, 08:58 PM
Takes some time but you will need to make sure you get that fan on that P Gasser straight and very little run out.
Thanks as always Rodney! I will. I've just received a digital Mitutoyo DTI w/ magnetic base + a pretty descent sized vice to hold the engine snug during the runout measurements and modifications.
One thing that I haven't figured out yet is on how to balance the fan itself? What are you guys using to mount this thing to allow it to spin freely? I saw a video on this forum of some guy using 2 blocks of ice... There's gotta be a better way?
PaulH
09-30-2006, 09:11 PM
Just use a Dubro high-point balancer. If the cones fit, you're in business.
asong26
09-30-2006, 10:44 PM
Just use a Dubro high-point balancer. If the cones fit, you're in business.
Did you use this on your bergen?
PaulH
10-01-2006, 07:28 AM
No, I never bothered. I probably should even though I have a Canfield (harmonic) balancer mounted to my fan.
cbergen
10-02-2006, 12:19 AM
asong,
My apologies for answering a question from the "other" forum here,
The model set up in the G3 Expansion Pak 1 is what we call an EB.
If you look into the editing portion of the model you will find 810mm blades at 250 grams.
It is geared 7.5:1 and the governor is set at 1450, 1550, and 1650.
Pitch is set at +-8 degrees, and cyclic is set at 6 degrees.
So in effect, your hypothesis of it being good for AP is 100% correct because it is setup exactly in that way.
Who is to blame for this? That would be me! I did the final changes before sending them to KE for production. I beleive the simulator to be a training tool, mostly for beginners, but also as a tool to work on orientations, new manuevres, and the like. Therefore, I set it up with stability in mind, knowing that most buy these machines as a lifting tool, and with quite a few going to new people in the hobby, I wanted them to have an accurate representation of what they are buying.
I suppose I could have programmed a 3D monster, adjusting for an outrageous power to weight ratio, but that would be somewhat dishonest now wouldn't it?
If you like, I can send you some editing details to set it up more along the lines of a 3D bird.
asong26
10-02-2006, 02:29 AM
asong,
My apologies for answering a question from the "other" forum here,
The model set up in the G3 Expansion Pak 1 is what we call an EB.
If you look into the editing portion of the model you will find 810mm blades at 250 grams.
It is geared 7.5:1 and the governor is set at 1450, 1550, and 1650.
Pitch is set at +-8 degrees, and cyclic is set at 6 degrees.
So in effect, your hypothesis of it being good for AP is 100% correct because it is setup exactly in that way.
Who is to blame for this? That would be me! I did the final changes before sending them to KE for production. I beleive the simulator to be a training tool, mostly for beginners, but also as a tool to work on orientations, new manuevres, and the like. Therefore, I set it up with stability in mind, knowing that most buy these machines as a lifting tool, and with quite a few going to new people in the hobby, I wanted them to have an accurate representation of what they are buying.
I suppose I could have programmed a 3D monster, adjusting for an outrageous power to weight ratio, but that would be somewhat dishonest now wouldn't it?
If you like, I can send you some editing details to set it up more along the lines of a 3D bird.
Chris,
That would be great! You should've seen the look on my face when I first fired up your heli on G3. I didn't tinker the settings at all, but knew something had to be wrong based on my false expectations. Better yet, you should save a 3D version of your heli's settings and post them on KnifeEdge, here or even RR for everyone to see! I am willing to bet that many not following the forums would get the wrong ideas about your product.
You're a great guy, and I am sure your products are just as great. I wish you much success!
Rodney
10-02-2006, 08:45 AM
The balancer, make sure you dont get the one with magnets ans it wont hold your fan assy.