SMALL - espritmodel.com SMALL - Telemetry SMALL - Radio
Reply
Thread Tools
Old Aug 30, 2005, 01:19 PM
Registered User
Monmouth UK
Joined Oct 2004
1,043 Posts
DIY Blade balancer

Cost 50p
hb888 is offline Find More Posts by hb888
Reply With Quote
Sign up now
to remove ads between posts
Old Aug 30, 2005, 08:35 PM
Suspended Account
Eeeeky's Avatar
Roosevelt UT
Joined Oct 2004
1,982 Posts
good idea dude!!!!!!thank you now i can balance the little !@#$%
Eeeeky is offline Find More Posts by Eeeeky
Reply With Quote
Old Aug 31, 2005, 03:39 AM
Heli Newbie!
singapore
Joined Jun 2005
58 Posts
do u have to put both blades wif the leading edge facing up
OR
one facing up and the other's leading edge facing down?
ChRiS OnG is offline Find More Posts by ChRiS OnG
Reply With Quote
Old Aug 31, 2005, 03:50 AM
Registered User
Monmouth UK
Joined Oct 2004
1,043 Posts
Hi Chris,

I placed the leading edge of both blades facing down as this was the wider than the trailing edge and so I could line it up on the table surface to ensure both blades were horizontal before tightening up the nut and bolt in the middle.
hb888 is offline Find More Posts by hb888
Reply With Quote
Old Aug 31, 2005, 08:29 AM
Heli Newbie!
singapore
Joined Jun 2005
58 Posts
ok thnkx!
ChRiS OnG is offline Find More Posts by ChRiS OnG
Reply With Quote
Old Aug 31, 2005, 08:39 AM
Vampyre Inc
HoverDown3K's Avatar
Rochester, New York
Joined Nov 2004
2,562 Posts
Great Idea!!! I am making one!

You can paint or use marker to color the credit cards, it will give it a more finished
look.

Well Done!
HoverDown3K is offline Find More Posts by HoverDown3K
Reply With Quote
Old Aug 31, 2005, 08:58 AM
Heli-addicted
Melbourne, Australia
Joined May 2005
203 Posts
This is only half of the balancing equation, though. Both blades need to have the same Centre of Gravity, or it doesn't work. To c of g the blades, hold a blade of some sort (ie knife) on edge and lay the blade across it, moving it along until it balances. Mark this point on the blade. Do the same to the other one. Compare the marks. If they are not equal, add weight (tape of some sort) to the tip of a blade to move the c of g out, or near the root to move it in. When they are equal, balance as per the pics, and add weight to the lighter blade at its c of g. They are now static balanced. Bear in mind that static and dynamic balance are not always the same, but are usually near enough for us!

Cheers

James
kwikee is offline Find More Posts by kwikee
Reply With Quote
Old Aug 31, 2005, 09:02 AM
Vampyre Inc
HoverDown3K's Avatar
Rochester, New York
Joined Nov 2004
2,562 Posts
Quote:
Originally Posted by kwikee
This is only half of the balancing equation.....
Cheers
James
Yes 100% agree that is only 1/2 the balacing act!, for more info or a picture of what Kwikee is talking about check out this link.

http://www.helihobby.com/html/balancing_blades.html
HoverDown3K is offline Find More Posts by HoverDown3K
Reply With Quote
Old Aug 31, 2005, 09:32 AM
Registered User
Monmouth UK
Joined Oct 2004
1,043 Posts
Yes correct about the process. I'm following the guide on www.trextuning.com.

The other modification I made to the process was to bluetac the kitchen knife to the table with the handle hanging off the table in order to get the knife blade truly vertical. The yellow plastic rotor blades tended to slip off the knife edge very easily if it was not 100% vertical.
hb888 is offline Find More Posts by hb888
Reply With Quote
Old Aug 31, 2005, 10:41 AM
Got my ears on
Beige's Avatar
England (oxfordshire)
Joined Sep 2001
303 Posts
My hi-tech approach...

2 cans of custard, on a nice level surface (checked with a level) bit of piano wire and a couple of collets





And i stick a bit of thin alu in a vice to get the CoG
Beige is offline Find More Posts by Beige
Reply With Quote
Old Aug 31, 2005, 12:55 PM
That tree again!!!!
thanhTran's Avatar
Germantown, MD, US
Joined Sep 2004
6,642 Posts
Quote:
Originally Posted by kwikee
...To c of g the blades, hold a blade of some sort (ie knife) on edge and lay the blade across it, moving it along until it balances. Mark this point on the blade. Do the same to the other one. Compare the marks. ...
I followed this method from advices from one of the fellow members here. I found it's hard to find a perfect CG for the blade. When doing it on the knife (hold by a vice), I found that if I move the blade just a little, the blade tilt to one side. Move back just a little, the blade tilted the other side. I can't never find a position that the blade can balance by itself on the knife. I could only find a position that the blade seems to balance because it changes its level slower than other position. How do you work around this? I.e Are you able to set the blade level on the knife by itself? Without a perfect CG, I found most of the blades coming out from manufacture have identical cg, but they are not really smooth.

Thanks

thanh
thanhTran is offline Find More Posts by thanhTran
Reply With Quote
Old Aug 31, 2005, 08:39 PM
The Great Santini
Santini's Avatar
Madison, NJ 07940
Joined Dec 2004
1,922 Posts
I find the cog using a razor blade taped to the corner of a tape measure placed on its side. The edge of the which gives a good guide to make sure the blade is perpendicular to the blade. It is very low to the table, so my hands are steadied on the table and I use my index fingers to move the blade around.

Sure, it takes some trial and error, but a razor is a bit "grippy", so I am able to lift and move the blade a smidge at a time until it hangs there for a few seconds or more and does not appear to a have bias to teeter either way. That is where I mark the blade. I get really good results every time and after a little practice it only takes a few minutes to mark the blades and complete this part of the balancing.
Santini is offline Find More Posts by Santini
Reply With Quote
Old Aug 31, 2005, 09:09 PM
Its all fun
Tonystott's Avatar
Australia, NSW, Forster
Joined Oct 2004
7,210 Posts
Can someone please send me a couple of their credit cars so I can do this too?
Tonystott is offline Find More Posts by Tonystott
Reply With Quote
Old Oct 01, 2005, 05:03 PM
Registered User
Kentucky
Joined Dec 2003
1,744 Posts
Good to know.
Johnny B is offline Find More Posts by Johnny B
Reply With Quote
Old Oct 01, 2005, 11:29 PM
That tree again!!!!
thanhTran's Avatar
Germantown, MD, US
Joined Sep 2004
6,642 Posts
Quote:
Originally Posted by Santini
...
Sure, it takes some trial and error, but a razor is a bit "grippy", so I am able to lift and move the blade a smidge at a time until it hangs there for a few seconds or more and does not appear to a have bias to teeter either way. That is where I mark the blade. I get really good results every time and after a little practice it only takes a few minutes to mark the blades and complete this part of the balancing.
It takes me about 3 - 4 mins each blade to decide which point is better for the CG to mark the line. I wonder if the professionally made balancer would allow us to balance the blade faster? Anyone has any experience?

thanh
thanhTran is offline Find More Posts by thanhTran
Reply With Quote
Reply


Thread Tools

Similar Threads
Category Thread Thread Starter Forum Replies Last Post
helicopter blade balancer xxcysxx Electric Heli Talk 19 Mar 08, 2007 07:01 PM
KSJ Blade Balancer Question Orion_V Electric Heli Talk 19 May 08, 2005 10:39 PM
K&S Blade Balancer w/ Corona Blades Shiba Electric Heli Talk 2 Feb 24, 2004 01:37 PM
homemade simple Corona blade balancer Tom Cardiff Electric Heli Talk 9 Nov 08, 2003 11:49 AM
KSJ-528 blade balancer mod TMorita Electric Heli Talk 1 Jan 26, 2003 06:34 AM