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MY 1/2a+ PBF - 7/9/2003 8:32:33 PM   
ZB50



Posts: 469
Joined: 12/10/2001
From: Montgomery, AL, USA
Status: offline 		Hi all,

I just finished and test flew my 18x18 PBF. (it took appx. 6 hours for me to build). This includes "hunting and finding all the tools, parts",, everything. "What a handfull at first". I dorked it on the first hand launch due to my or (lack of) heave or technique. The second launch was just great. It is quite nimble and quick. I had just ran a few tanks of sig 25% the Norvel .074 on a test stand. (New cyl and piston due to broken con rod because I hit it with my sullivan starter and it was flooded) ((Beware of this)) I'm happy to say it idles great, transition is good and top end is very nice. I still have to find the right click for it tho. I think I had it a little lean as it stalled once with me and when I went into a hover with it, it would sag.... That says lean I think. Any way. I use a HiTec Flash 5sx and have a Hitec 555 rx. 2 GWS mini BB servos, 1 HS 81 (rudder), and a cirrus cs-20 micro for the throttle. The power for the flite system is a homemade 270ma NiMh pack strapped under the belley. First flight was with a MAS 6-3 prop.
I balanced it at 4 and 1/4 inches.
Best I can tell it weighs about 18 oz.
This is fun. I did not time my flights but the 2 oz tank provides pleanty of flight time.

ZB

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Photos - 7/9/2003 8:35:53 PM   
ZB50



Posts: 469
Joined: 12/10/2001
From: Montgomery, AL, USA
Status: offline 		Can someone please tell me how to make the photos larger in the attachments?

Thanks,

ZB

(in reply to ZB50)
       Post #: 2

MY 1/2a+ PBF - 7/9/2003 8:39:51 PM   
Crash90



Posts: 2315
Joined: 10/5/2002
From: Cressona, PA, USA
Status: offline 		I use a program called vueprint_pro which can be found at [url]www.hamrick.com[/url]

It is basically a picture viewer however it does allow me to resize images rather easily. I can enlarge or shrink any photo as needed.

(in reply to ZB50)
       Post #: 3

MY 1/2a+ PBF - 7/9/2003 10:17:44 PM   
goldguy


 

Posts: 339
Joined: 11/7/2002
From: Nanaimo, BC, CANADA
Status: offline 		Jimmy:

To launch my PBF, I hold it out at arm's length, using the serovs as a grip, at about a 45 degree angle. Up the throttle to high idle, let go and walk back. I will slowly climp away and away you go.

I now have wheels and a skid and taxi it out like those "real planes" and don't break any more props tp boot.

_____________________________

Frank Weaver

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       Post #: 4

Re: MY 1/2a+ PBF - 7/11/2003 8:40:37 AM   
putt_13



Posts: 347
Joined: 9/16/2002
From: Chilton, WI, USA
Status: offline 		[QUOTE]Originally posted by ZB50
(New cyl and piston due to broken con rod because I hit it with my sullivan starter and it was flooded) ((Beware of this))[/QUOTE]

Whats this all about. I am new to the glow world, and wouldnt want to break my engine by doing what you did. What exactly happened. The motor was flooded, and you tried to start it. Why did the "con rod" break. Thanx -Patrick

(in reply to ZB50)
       Post #: 5

MY 1/2a+ PBF - 7/11/2003 9:16:24 AM   
Lynn S



Posts: 1503
Joined: 1/31/2003
From: Bolivar, TN, USA
Status: offline 		Flooded means there is way too much fuel in the engine cylinder. A flooded engine will not run or is very hard to start. If there is enough fuel in the cylinder the piston can not make the full stroke to the top of the cylinder. (liquids do not compress like air does)
something has to give when the crankshaft trys to force the piston to the top, then the rod can break.

(in reply to ZB50)
       Post #: 6

MY 1/2a+ PBF - 7/11/2003 9:25:27 AM   
putt_13



Posts: 347
Joined: 9/16/2002
From: Chilton, WI, USA
Status: offline 		Is the rod the piece of metal that makes up the piston?? Also, how can you unflood and engine, and how do you know if it is flooded?? -patrick

(in reply to ZB50)
       Post #: 7

MY 1/2a+ PBF - 7/11/2003 9:36:01 AM   
Lynn S



Posts: 1503
Joined: 1/31/2003
From: Bolivar, TN, USA
Status: offline 		Just look at any drawing of an engine with a piston (lawnmower, car, ect) the piston is like a little can that moves up and down inside the cylinder. It is connected to the crankshaft (the part that turns the prop) by a connecting rod. The rod connects the piston to the cranshaft. It is made like a straight bar with holes in the ends to connect to the wrist pin in the piston and a round throw on the crankshaft.
Just go to a lawnmower shop and look at some junk 2 stroke engines. You will see the basic parts. You can also find cut away drawings on the internet.

You will know it is flooded when it spits fuel back out the carb. You can take the plug out and pour the excess fuel out or just disconnect the fuel line and flip it over by hand , anything to get it out.

(in reply to ZB50)
       Post #: 8

MY 1/2a+ PBF - 7/11/2003 9:42:50 AM   
putt_13



Posts: 347
Joined: 9/16/2002
From: Chilton, WI, USA
Status: offline 		Thanx Lynn...your a real help for use newbie glow pilots. -Patrick

(in reply to ZB50)
       Post #: 9

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