RE: wild hare, LR-1 pylon racer

RE: wild hare, LR-1 pylon racer
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RE: wild hare, LR-1 pylon racer - 12/27/2005 12:29:38 AM

65010

Posts: 50
Joined: 12/26/2005
From: MelbourneVIC, AUSTRALIA
Status: offline

Thanks for that.

I contacted the manufacturer (where I brought) mine - Xtreme Composites in Bangkok, Thailand. They sent me a diagram that showed the CG to be in the range from 7.5 to 8.0 cm (3 to ~ 3 3/16 inches) behind the front of the wing. I set it up at 7.5 cm and it snapped inverted on take off on its first flight when it was about 3 metres in the air....

I subsequently calculated the aerodynamic centre of the wing to be about 6.3 cm behind the front of the wing. Seems the CG would be better around there.

The manufacturer insists that they fly fine in the 7.0 to 8.0 cm range. Was interested in what others experienced...

(in reply to freakingfast)

Post #: 76

RE: wild hare, LR-1 pylon racer - 12/27/2005 2:13:41 AM

smokingwreckage

Posts: 242
Joined: 7/7/2005
From: , TX, USA
Status: offline

6.5 cm from the leading edge.

(in reply to 65010)

Post #: 77

RE: wild hare, LR-1 pylon racer - 12/27/2005 3:47:10 AM

Airbike

Posts: 600
Joined: 3/18/2003
From: Walnut, CA, USA
Status: offline

I second the CG from smokingwreckage,

I fly my LR-1's (Jett 50 & Brushless w/Lipo's) at 2 1/2" to 2 5/8" (6.35 cm to 6.66 cm). Am able to slow down quite well (at least the gas one) for landings with no signs of snapping/tip stalls. The electric version is much cleaner and is harder for me to slow it down.

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Post #: 78

RE: wild hare, LR-1 pylon racer - 12/27/2005 4:41:33 AM

Rebellion

Posts: 982
Joined: 2/22/2004
From: Central, GA, USA
Status: offline

Airbike, what setup are you using in the electric version?

(in reply to Airbike)

Post #: 79

RE: wild hare, LR-1 pylon racer - 12/27/2005 5:09:05 AM

Crazy4Flight

Posts: 2241
Joined: 9/15/2002
From: Milford, MI, USA
Status: offline

quote:

ORIGINAL: Airbike-RCU

OK, Got it all stuffed in.

LR-1 with Jett 50 and 8 oz BubbleJett tank.

AUW empty is 3 lb- 10 oz., That should be manageable (I flew my electric version at over 4 lbs) and get this, I didn't have to add any lead to balance. I just used a heavier 5 cell Rx batt in the tail and it balances the same as the OS .37 SZH & Macs muffler.

Now I need to test fly this little monster and play with props. I've ran the engine about 7 tanks on a test bench so far and I'll fly it first with a APC 7.2 x 8.0 pylon prop, turns about 21000 static, so I'll set it about 20400 or so and let her go!

New firewall is 1/4 ply set about 5/8" back from original location.

DID you make a template of that firewall????? can you send me a copy????
I have a LR-1 bought it last Apiril, at Toledo ...
And have JETT 50 side exaust with headder and tuned pipe looking for a home.

it would save me the cost of a new Jett .35BSE

Bob

(in reply to Airbike)

Post #: 80

RE: wild hare, LR-1 pylon racer - 12/27/2005 6:43:04 AM

freakingfast

Posts: 800
Joined: 1/3/2005
From: mather, CA, USA
Status: offline

Wow, that's some extreme range we have for CG. from a short of 2'' to a long of 3 3/16. Just imagine how forgiving a plane this is if it actually could fly throughout this range. I didn't like the numbers I was given, it just didn't look right even by eye ball.
Glad that 65010 brought the topic up. I'm going to use 6.5cm as the mark based on the experience of the guys here so far.
Thanks guys!

< Message edited by freakingfast -- 12/27/2005 6:44:29 AM >

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(in reply to Crazy4Flight)

Post #: 81

RE: wild hare, LR-1 pylon racer - 12/27/2005 8:49:59 AM

Airbike

Posts: 600
Joined: 3/18/2003
From: Walnut, CA, USA
Status: offline

e-dave, my experiment with electric power for the LR-1 kinda went like this:

Aveox 36/24/1.5 spinning apc 7x7 to 7x9 props.

1st, I burned up a Phoenix 80 because it was pulling around 100 amps at 3S lipo voltage (3S3P using TP 2100 cells)

Bought Phoenix-125 and got around 10 flights or so, motor stopped in the air and was literally smoking when I landed. I suppose the Aveox was only rated for 50 - 60 amps continuous. Sent it to Aveox and got it repaired.

If you want the LR-1 to fly fast, you'll need about 1500 watts, the 1000 watts I was using was not too bad, around 110-120 mph level (radared).

Now I tried to fly it with the replacement Phoenix-80 and smaller prop 6.5x6.5, and it barely stays in the air. Now its just hanging around the house.

The Phoenix 125 went into a hotliner with a Neu 1506/1D motor (Kv=9800

)and 6.7:1 gear box and pulling about 160Amps.

I would recommend going with a high voltage setup, at least 6S and keep the amps lower. I believe Joe Ford from Castle Creations was setting up one of these with something like a 10S and custom wound motor.

Crazy4flight: email your address to me at airbike711@aol.com The template that I used is pretty rough, I filled any gaps to the fuse with fiberglass and epoxy

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Post #: 82

RE: wild hare, LR-1 pylon racer - 12/27/2005 9:36:30 AM

65010

Posts: 50
Joined: 12/26/2005
From: MelbourneVIC, AUSTRALIA
Status: offline

Thanks for the feedback.

(in reply to Airbike)

Post #: 83

RE: wild hare, LR-1 pylon racer - 12/28/2005 5:59:22 AM

Crazy4Flight

Posts: 2241
Joined: 9/15/2002
From: Milford, MI, USA
Status: offline

quote:

ORIGINAL: Airbike-RCU

OK, Got it all stuffed in.

LR-1 with Jett 50 and 8 oz BubbleJett tank.

AUW empty is 3 lb- 10 oz., That should be manageable (I flew my electric version at over 4 lbs) and get this, I didn't have to add any lead to balance. I just used a heavier 5 cell Rx batt in the tail and it balances the same as the OS .37 SZH & Macs muffler.

Now I need to test fly this little monster and play with props. I've ran the engine about 7 tanks on a test bench so far and I'll fly it first with a APC 7.2 x 8.0 pylon prop, turns about 21000 static, so I'll set it about 20400 or so and let her go!

New firewall is 1/4 ply set about 5/8" back from original location.

Airbike,

Why did you move the fire wall back? I just finish carving the engine bay for my Jett .50 and it should fit. I am going to make an aluminum mount for it like I did for my F-4 Jett 1.20. Looks like the headder and pipe will have a bit of - ground clearance tho.

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(in reply to Airbike)

Post #: 84

RE: wild hare, LR-1 pylon racer - 12/28/2005 7:06:46 AM

Airbike

Posts: 600
Joined: 3/18/2003
From: Walnut, CA, USA
Status: offline

The opportunity to install a new firewall came because the original firewall, which is only 3 mm thick (.118"

shook loose when the OS .37 SZH threw a prop blade at full throttle.

I had a Great Planes .40 size FRP engine mount so I moved the new firewall to fit. If you're using an alum mount, it might be thin enough where you don't have to move the firewall back. I would still recommend adding a doubler to the original firewall, it's only 3 ply lite ply. Or fiberglass the firewall to the fuse.

I found what I used for my template; the original firewall!

If you want, I can just make a photocopy of it and fax it to you if you'd like.

edit: I see you're using the wheels that came with the plane, they don't hold up so I used a couple of Williams Bros 1.5" tailwheels instead.

< Message edited by Airbike-RCU -- 12/28/2005 7:09:36 AM >

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Post #: 85

RE: wild hare, LR-1 pylon racer - 12/29/2005 1:29:31 AM

Rebellion

Posts: 982
Joined: 2/22/2004
From: Central, GA, USA
Status: offline

quote:

ORIGINAL: Airbike-RCU

e-dave, my experiment with electric power for the LR-1 kinda went like this:

Aveox 36/24/1.5 spinning apc 7x7 to 7x9 props.

1st, I burned up a Phoenix 80 because it was pulling around 100 amps at 3S lipo voltage (3S3P using TP 2100 cells)

Bought Phoenix-125 and got around 10 flights or so, motor stopped in the air and was literally smoking when I landed. I suppose the Aveox was only rated for 50 - 60 amps continuous. Sent it to Aveox and got it repaired.

If you want the LR-1 to fly fast, you'll need about 1500 watts, the 1000 watts I was using was not too bad, around 110-120 mph level (radared).

Now I tried to fly it with the replacement Phoenix-80 and smaller prop 6.5x6.5, and it barely stays in the air. Now its just hanging around the house.

The Phoenix 125 went into a hotliner with a Neu 1506/1D motor (Kv=9800 )and 6.7:1 gear box and pulling about 160Amps.

I would recommend going with a high voltage setup, at least 6S and keep the amps lower. I believe Joe Ford from Castle Creations was setting up one of these with something like a 10S and custom wound motor.

Crazy4flight: email your address to me at airbike711@aol.com The template that I used is pretty rough, I filled any gaps to the fuse with fiberglass and epoxy

Sounds like you had a pretty hot setup.

I was curious about your results since going with an e-setup would avoid cutting the opening in the cowl for the engine ( obviously ) and preserve the clean lines on the front end.

One more question, do you think a F.I.R.E engine could be mounted inverted with a full length pipe ?

Thanks,

Dave

(in reply to Airbike)

Post #: 86

RE: wild hare, LR-1 pylon racer - 12/29/2005 8:10:00 AM

Airbike

Posts: 600
Joined: 3/18/2003
From: Walnut, CA, USA
Status: offline

Yeah, the electric version is definitely cleaner. Takes much longer to slow it down for landing. Its just that trying to get 1000 watts into it was killing the Lipos too quickly ($$$$$

)

Someone gave me a pair of Supertiger X40 engines (R.I.R.E.) and I tried to make it fit, but would've had to cut too much of the firewall and cheek cowl away to clear the angled exhaust pipe. I never thought about mounting it inverted. The nose section slopes downward from the spinner to the wing LE so I don't think an angled exhaust pipe would fit. Perhaps a shallow "S" shaped header might work but it would be a lot of firewall cutting. Then there would also be no clearance for the pipe unless you used some aftermarket landing gear that was taller.

It would be easier to mount a F.I.R.E. engine upright with the header and pipe on top, although it would be quite ugly.

_____________________________

The more you put into living, the more you get out of life.
Revver #150

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Post #: 87

RE: wild hare, LR-1 pylon racer - 12/31/2005 5:09:07 AM

Crazy4Flight

Posts: 2241
Joined: 9/15/2002
From: Milford, MI, USA
Status: offline

Airbike,

I made a paper template from existing firewall. made firewall doubler from 3/16 ply cut it in half to fit it behind the existing firewall. Glued it in place with loctite Hysol 4692. Intalled my mount and dremelled the fuse away to fitt the JETT .50. Made the mount at my toolshop from a solid piece of 6061-T6.

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< Message edited by Crazy4Flight -- 12/31/2005 5:19:37 AM >

(in reply to Airbike)

Post #: 88

RE: wild hare, LR-1 pylon racer - 1/7/2006 4:31:55 AM

Crazy4Flight

Posts: 2241
Joined: 9/15/2002
From: Milford, MI, USA
Status: offline

I had to make a muffler extention. It is .50 long with 2 degree angle to tip the back end away from the fuse. Also the landing gear was shifter to the right 1/16" by elongating the screw hole.

Bob27 does Dub offera nitrous kit for the .50?

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(in reply to Crazy4Flight)

Post #: 89