VansAirForceForums  
Home > VansAirForceForums

- POSTING RULES
- Donate yearly (please).
- Advertise in here!

- Today's Posts | Insert Pics


Go Back   VAF Forums > RV Firewall Forward Section > Propellers
Register FAQ Members List Calendar Today's Posts

Reply
 
Thread Tools Search this Thread Display Modes
  #21  
Old 11-03-2018, 07:22 PM
bret's Avatar
bret bret is offline
 
Join Date: Feb 2010
Location: Gardnerville Nv.
Posts: 2,828
Default

What a great offer, I lived in Ramona 20 years ago, if I ever get down that way I'll come call on you. Thanks for your service.
__________________
7A Slider, EFII Angle 360, CS, SJ.
Reply With Quote
  #22  
Old 11-03-2018, 09:12 PM
scsmith scsmith is offline
 
Join Date: Jan 2008
Location: Ashland, OR
Posts: 2,574
Default no one should say 'no' to a prop balance

My Whirl Wind 200RV prop was initially about 0.35 ips....much better than average for a C/S prop. When Kregg Victory was done ( I think he used Dynavibe, but I forget) it was less then 0.015 ips.

I could convince myself that if I put my hand on the canopy rail, I could feel the difference. I don't really know for sure if I could feel it.

But why on earth would you ever say 'no'?

So you have a plenum. I think we can find an alternative mount point for the accelerometer, but might not need to. Your plenum must attach firmly at the front of the engine somewhere to the case. Where ever that attachment is, put the accelerometer there.

I would say anyone within an hour's flight of Ramona that has not had a dynamic prop balance should call 'jask' and make an appointment.
__________________
Steve Smith
Aeronautical Engineer
RV-8 N825RV
IO-360 A1A
WW 200RV
"The Magic Carpet"
Hobbs 625
LS6-15/18W sailplane SOLD
bought my old LS6-A back!!
VAF donation Jan 2020
Reply With Quote
  #23  
Old 11-04-2018, 06:26 AM
BillL BillL is offline
 
Join Date: Sep 2007
Location: Central IL
Posts: 5,516
Default How much is prop and how much is spinner?

The whole thread calls this prop balance, but during a Hartzell factor tour I watched them balance check each prop at the end of the line. Many needed nothing some, only needed a #10 washer or half washer.

But - the back plate using a fiberglass nose cone seems like it could generate quite the opportunity for imbalance, not to mention uneven painting.

What is your experience with metal spinners vs glass ones for initial imbalance?
__________________
Bill

RV-7
Lord Kelvin:
“I often say that when you can measure what you are speaking about,
and express it in numbers, you know something about it; but when you
cannot measure it, when you cannot express it in numbers, your knowledge
is of a meager and unsatisfactory kind.”
Reply With Quote
  #24  
Old 11-04-2018, 08:17 AM
David Paule David Paule is offline
 
Join Date: Dec 2009
Location: Boulder, CO
Posts: 4,435
Default

Quote:
Originally Posted by jask View Post
One of the publications on prop balancing describes how to measure propeller track and the limitations. The spark plugs are removed, engine rotated and blade track is noted. I'm sure you could do the same for blade pitch. That is corrected by work on the propeller or prop mounting, not balancing.
At least on helicopters, the track was tested dynamically. I wouldn't expect a static prop track to do more than verify the prop mounting.

Dave
Reply With Quote
  #25  
Old 11-04-2018, 09:14 AM
Walt's Avatar
Walt Walt is offline
 
Join Date: Aug 2005
Location: Dallas/Ft Worth, TX
Posts: 5,686
Default

My DSS balancer is certainly capable of Dynamic blade tracking (normal stuff on Helos) , but because tracking is not generally performed on aircraft I didn't purchase this option.

__________________
Walt Aronow, DFW, TX (52F)

EXP Aircraft Services LLC
Specializing in RV Condition Inspections, Maintenance, Avionics Upgrades
Dynamic Prop Balancing, Pitot-Static Altmeter/Transponder Certification
FAA Certified Repair Station, AP/IA/FCC GROL, EAA Technical Counselor
Authorized Garmin G3X Dealer/Installer
RV7A built 2004, 1700+ hrs, New Titan IO-370, Bendix Mags
Website: ExpAircraft.com, Email: walt@expaircraft.com, Cell: 972-746-5154
Reply With Quote
  #26  
Old 11-04-2018, 09:21 AM
Walt's Avatar
Walt Walt is offline
 
Join Date: Aug 2005
Location: Dallas/Ft Worth, TX
Posts: 5,686
Default

Quote:
Originally Posted by BillL View Post
The whole thread calls this prop balance, but during a Hartzell factor tour I watched them balance check each prop at the end of the line. Many needed nothing some, only needed a #10 washer or half washer.

But - the back plate using a fiberglass nose cone seems like it could generate quite the opportunity for imbalance, not to mention uneven painting.

What is your experience with metal spinners vs glass ones for initial imbalance?
Hartzell static balances their props, not at all the same thing as dynamic balance after you add all the other stuff like flywheel, spinner bulkhead, spinner etc..
(Hartzell recommends dynamic balancing in their owners manual)
I've seen quite a few cracked metal spinners but never a cracked fiberglass one.
For initial "imbalance" not much different between metal and glass, seen quite a few bad ones in both camps.
__________________
Walt Aronow, DFW, TX (52F)

EXP Aircraft Services LLC
Specializing in RV Condition Inspections, Maintenance, Avionics Upgrades
Dynamic Prop Balancing, Pitot-Static Altmeter/Transponder Certification
FAA Certified Repair Station, AP/IA/FCC GROL, EAA Technical Counselor
Authorized Garmin G3X Dealer/Installer
RV7A built 2004, 1700+ hrs, New Titan IO-370, Bendix Mags
Website: ExpAircraft.com, Email: walt@expaircraft.com, Cell: 972-746-5154

Last edited by Walt : 11-04-2018 at 09:23 AM.
Reply With Quote
  #27  
Old 11-04-2018, 01:05 PM
scsmith scsmith is offline
 
Join Date: Jan 2008
Location: Ashland, OR
Posts: 2,574
Default

Quote:
Originally Posted by BillL View Post
The whole thread calls this prop balance, but during a Hartzell factor tour I watched them balance check each prop at the end of the line. Many needed nothing some, only needed a #10 washer or half washer.

But - the back plate using a fiberglass nose cone seems like it could generate quite the opportunity for imbalance, not to mention uneven painting.

What is your experience with metal spinners vs glass ones for initial imbalance?
You are really balancing the engine/prop system, with all its attachments. At least in my case, the balance weights (bolt and washers) were attached to the ring gear.

I did have a friend with a poorly fitting spinner -- the attach screws were continually working loose and the spinner screw holes were wearing oval. He could not get a good dynamic balance until that was fixed. So it does show that there is some participation in the balance from the spinner, even though it is pretty light, and not very far from the rotation axis.
__________________
Steve Smith
Aeronautical Engineer
RV-8 N825RV
IO-360 A1A
WW 200RV
"The Magic Carpet"
Hobbs 625
LS6-15/18W sailplane SOLD
bought my old LS6-A back!!
VAF donation Jan 2020
Reply With Quote
  #28  
Old 11-04-2018, 01:12 PM
vic syracuse vic syracuse is offline
Super Moderator
 
Join Date: May 2005
Location: Locust Grove, GA
Posts: 2,626
Default

I've been balancing props for a few years now. One difference I notice is that there seems to be a lot less cracking of baffling and other metal parts on the airplanes that have their props balanced.

Vic
__________________
Vic Syracuse

Built RV-4, RV-6, 2-RV-10's, RV-7A, RV-8, Prescott Pusher, Kitfox Model II, Kitfox Speedster, Kitfox 7 Super Sport, Just Superstol, DAR, A&P/IA, EAA Tech Counselor/Flight Advisor, CFII-ASMEL/ASES
Kitplanes "Unairworthy" monthly feature
EAA Sport Aviation "Checkpoints" column
EAA Homebuilt Council Chair/member EAA BOD
Author "Pre-Buy Guide for Amateur-Built Aircraft"
www.Baselegaviation.com
Reply With Quote
Reply



Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump


All times are GMT -6. The time now is 03:43 AM.


The VAFForums come to you courtesy Delta Romeo, LLC. By viewing and participating in them you agree to build your plane using standardized methods and practices and to fly it safely and in accordance with the laws governing the country you are located in.