CG Machine
#1
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CG Machine
So I bought the Great Planes CG Machine, thinking it would work for my jet since it says up to 40 LBS.
I would not even use this machine for a foamy, what a piece of junk. The little pad slip off the rods and mess up the jet finish. Got some nice scraches on the bottom of my wings. Also the box, and the directions both show the little rulers sitting nice and parallel in the air. BULL _ CARP. They hand all caddy whompus at an angle and the rulers fall forward.
I have no one to help me except my wife and that is usually a frustrating process trying to use my fingers and hers, though that is how I've done it on 2 jets so far.
So, any tips on measuring CG?
I would not even use this machine for a foamy, what a piece of junk. The little pad slip off the rods and mess up the jet finish. Got some nice scraches on the bottom of my wings. Also the box, and the directions both show the little rulers sitting nice and parallel in the air. BULL _ CARP. They hand all caddy whompus at an angle and the rulers fall forward.
I have no one to help me except my wife and that is usually a frustrating process trying to use my fingers and hers, though that is how I've done it on 2 jets so far.
So, any tips on measuring CG?
#7
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RE: CG Machine
I've had the c.g. machine for about ten years and used it on my Reaction and a Carf Hawk. The Hawk required the assistance of my 12 year old to supprt one end while I got it in position but I would have needed help no matter what I was using. For the Hawk I had to use music wire instead of the supplied rods to have the haves go wider and clear the fuse. Take the rulers out and use painters tape to mark the CG range and protect the wing. Once you get it on where it's balanced, you can put the rulers back in and get them parallel. It is doable. I looked at the EZ balancer II but thought it was way too much money for a couple pieces of aluminum, foam and hardware.
Marty
Marty
#9
RE: CG Machine
ORIGINAL: luv2flyrc
+1
Excellent unit, allows you to move componants around while balancing as it won't let the plane fall Worth the money, makes a job that used to be a PITA, a piece of cake now!
Mike
+1
Excellent unit, allows you to move componants around while balancing as it won't let the plane fall Worth the money, makes a job that used to be a PITA, a piece of cake now!
Mike
#10
RE: CG Machine
I built one of these:
http://www.rcuniverse.com/forum/m_11...m.htm#11309392
Simple, cheap, safe, easy to use.
It may not be technical enough or expensive enough to impress the guys at the field though . - John.
http://www.rcuniverse.com/forum/m_11...m.htm#11309392
Simple, cheap, safe, easy to use.
It may not be technical enough or expensive enough to impress the guys at the field though . - John.
#12
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RE: CG Machine
Actually, the Great Plains CGMachine works well if modified with the addition of vertical dowel rods from the pivot points to the base of the machine. The mod forms a triangle which is very rigid. Ichose fibreglass driveway markers (1/4" diameter) but any stiff rod material, such as arrow shafts or metal rods, could be used. The reinforcing rods are secured to the top of the existing rods with CF or kevlar tow and thru drilled holes in the machine's plastic base. All this was described in an RCJIarticle by Oliver Nicholas (Olinco) on prepping jets for their maiden flight. Unfortunately, I don't have the RCJIissue handy or a digital photo to post here. Ollie uses this modded CGMachine to balance large jets, weighing up to 60 lbs,and it works well forme on my jets-up to 25 lbs.
Art ARRO
Art ARRO
#13
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RE: CG Machine
I've used both the EZbalancer and the one suggested by Boomerang1, the easiest to use has been Boomerangs suggestion (and the most cost effective). I have checked the balance with both units and they both give the same results. The picture shows my T-33 being balanced. Very easy to use and components can be moved around to get the proper CG location.
#17
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RE: CG Machine
ORIGINAL: [email protected]
wait till i get to the field ill show them how smart iam what a way to balance
wait till i get to the field ill show them how smart iam what a way to balance
show us some pictures how you doing came on
#20
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RE: CG Machine
ORIGINAL: essyou35
So I bought the Great Planes CG Machine, thinking it would work for my jet since it says up to 40 LBS.
I would not even use this machine for a foamy, what a piece of junk. The little pad slip off the rods and mess up the jet finish. Got some nice scraches on the bottom of my wings. Also the box, and the directions both show the little rulers sitting nice and parallel in the air. BULL _ CARP. They hand all caddy whompus at an angle and the rulers fall forward.
I have no one to help me except my wife and that is usually a frustrating process trying to use my fingers and hers, though that is how I've done it on 2 jets so far.
So, any tips on measuring CG?
So I bought the Great Planes CG Machine, thinking it would work for my jet since it says up to 40 LBS.
I would not even use this machine for a foamy, what a piece of junk. The little pad slip off the rods and mess up the jet finish. Got some nice scraches on the bottom of my wings. Also the box, and the directions both show the little rulers sitting nice and parallel in the air. BULL _ CARP. They hand all caddy whompus at an angle and the rulers fall forward.
I have no one to help me except my wife and that is usually a frustrating process trying to use my fingers and hers, though that is how I've done it on 2 jets so far.
So, any tips on measuring CG?