Weight of Tracy Obrien Gear Legs

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Weight of Tracy Obrien Gear Legs

Postby ededoad » Sun Jun 28, 2015 5:06 pm

I used Tracy Obrien gear legs and got a little surprise today. I new my Sonex was going to be a little bit heavy but after weighing today I found it to be 20 lbs or so heavier than I expected. Any one else experienced this? I can only think that this is the gear legs.
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Re: Weight of Tracy Obrien Gear Legs

Postby rizzz » Sun Jun 28, 2015 8:26 pm

What does it weigh?
Is it polished or painted? What engine? Tail dragger? Instruments? ...

You say heavier than expected, what did you expect and why?
Michael
Sonex #145 from scratch (mostly)
Taildragger, 2.4L VW engine, AeroInjector, Prince 54x48 P-Tip
VH-MND, CofA issued 2nd of November 2015
First flight 7th of November 2015
Phase I Completed, 11th of February 2016
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Re: Weight of Tracy Obrien Gear Legs

Postby ededoad » Sun Jun 28, 2015 10:17 pm

I am using a O-200 with light weight starter mag and alternator. about 210 lbs. All painted because of the gulf coast. Expected about 710 -720 lbs ended up at 764. Engine monitor, airspeed, 10000 foot altimeter and skid ball.
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Re: Weight of Tracy Obrien Gear Legs

Postby fastj22 » Mon Jun 29, 2015 10:14 am

When I converted from tri gear to conventional, I also went from the stock titanium to TOB legs. My weight didn't change significantly. I doubt your weight is due to the TOB legs.

John Gillis
SEL Private, Comm Glider, Tow pilot (Pawnee Driver)
Waiex N116YX, Jabiru 3300, Tail dragger,
First flight, 3/16/2013. 403 hours and climbing.
Home: CO15. KOSH x 5
Flying a B-Model Conversion (Super Bee Baby!)
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Re: Weight of Tracy Obrien Gear Legs

Postby kmacht » Mon Jun 29, 2015 12:28 pm

How did you weight the plane and what did you use for scales? The titanium legs aren't very light and I suspect that the TOB legs may be a pound or two heavier but no way is it 20lbs.

Keith
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Re: Weight of Tracy Obrien Gear Legs

Postby ededoad » Tue Jun 30, 2015 4:39 pm

I used electronic shipping scales and spirit levels. Used tire pressure to set center bubble. Don't think its the gear anymore. Just don't know where it is. Got emails from builders using similar alternate engines and I am still 20 lbs heavy. I am going to start weighing separate parts.
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Re: Weight of Tracy Obrien Gear Legs

Postby fastj22 » Tue Jun 30, 2015 8:19 pm

ededoad wrote:I used electronic shipping scales and spirit levels. Used tire pressure to set center bubble. Don't think its the gear anymore. Just don't know where it is. Got emails from builders using similar alternate engines and I am still 20 lbs heavy. I am going to start weighing separate parts.

The O200 is at LEAST 20 lbs more than the Jab 3300 or the Aerovee turbo. Probably more like 40 to 50 lbs. I think you will find your weight gain there. How is your CG? Is it really forward?
There's a reason the O200 is not a recommended power plant for the Sonex. And its not reliability or serviceability.

John Gillis
SEL Private, Comm Glider, Tow pilot (Pawnee Driver)
Waiex N116YX, Jabiru 3300, Tail dragger,
First flight, 3/16/2013. 403 hours and climbing.
Home: CO15. KOSH x 5
Flying a B-Model Conversion (Super Bee Baby!)
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Re: Weight of Tracy Obrien Gear Legs

Postby sonex892 » Wed Jul 01, 2015 5:56 am

Do you have bigger tires and hydraulic brakes? They will add quite a bit of weight.

Mine originally weighed 655lbs, but after a few minor mods. Big tires (McCreary Airhawks 5:00x 5)/ hydraulic brakes (Great plains) / new vents / dial a rudder trim, I re-weighed. It had fattened up 20 lbs to 675lbs. The big tires were the biggest contributors probably followed by the brakes.

Steve
Sonex 892
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Re: Weight of Tracy Obrien Gear Legs

Postby kmacht » Wed Jul 01, 2015 7:38 am

Not just the motor but what about the motor mount? The aerovee mount is pretty simple and light. Not sure what you have to mout the O-200 on.

It also might be worth trying a different set of scales just to confirm you really have a weight issue and it isn't a measuring problem. You said that you used electronic shipping scales. What is their weight range? Most scales don't measure accuratly in the first third of their load range.

Keith
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Re: Weight of Tracy Obrien Gear Legs

Postby ededoad » Wed Jul 01, 2015 12:05 pm

I understand that paint will add up to 20 lbs so there it is. This is primed in and out and painted. Also larger tires and a couple of lbs for the gear. It all adds up.

I guess I have to live with it now.

Thanks for all the input.
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