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Bvm Bob Cat Build thread!

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Old 04-21-2009, 02:15 PM
  #151
Lasse Palm
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Default RE: Bvm Bob Cat Build thread!


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ORIGINAL: JustABigKid

Lasse, did you weigh your finished Bobcat?
Yes!
But I do not remember, I will be back with the weight tomorrow.
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Old 04-21-2009, 02:53 PM
  #152
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Default RE: Bvm Bob Cat Build thread!

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ORIGINAL: JetCatJimmy

Excellent maiden!! And great work on the knife edge. I'm still trying to dial mine in. Did you program that in a mix, or is it all thumb work?
Knife edge mix whats that?
I train my thumbs on Shulman knife edges[8D]

Regards
Lasse Palm
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Old 04-21-2009, 03:03 PM
  #153
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Default RE: Bvm Bob Cat Build thread!

HA HA~! Yes, I need to just figure it out. I currently have no mixes loaded anyway and would love to keep it that way.
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Old 04-22-2009, 03:08 PM
  #154
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Default RE: Bvm Bob Cat Build thread!

Quote:
ORIGINAL: JustABigKid

Lasse, did you weigh your finished Bobcat?
Ken,the weight came out at 9833g with fuel in the Bvm UAT.

Lasse P
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Old 04-22-2009, 10:34 PM
  #155
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Default RE: Bvm Bob Cat Build thread!


Thanks! [8D]

Quote:
ORIGINAL: Lasse Palm

Quote:
ORIGINAL: JustABigKid

Lasse, did you weigh your finished Bobcat?
Ken,the weight came out at 9833g with fuel in the Bvm UAT.

Lasse P
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Old 04-23-2009, 01:49 PM
  #156
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Default RE: Bvm Bob Cat Build thread!

Grattis Lasse! till en i mitt tycke en lite tuff men bra premiärflygning

Christer Pekkala
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Old 04-24-2009, 02:16 AM
  #157
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ORIGINAL: Pekkala

Grattis Lasse! till en i mitt tycke en lite tuff men bra premiärflygning

Christer Pekkala
Tack Christer,
modellen flyger som en dröm så jag kunde inte låta bli att känna lite på den he,he

Hälsningar
Lasse P
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Old 04-24-2009, 05:29 AM
  #158
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Default RE: Bvm Bob Cat Build thread!

Hi,

I am nearly finished with mine. Hopefully the maiden flight tomorrow.
My BC has the new JetCAT P-80 SE kerostart installed. (with 97N - a bit over 22lbs of thrust)

I am struggling with the flap throw and flap mixer settings, though.
I do not understand the recommendations of the BVM website on this.
Can one of you experts tell me how much flaps you use and how much elevator downtrim you mix in ?
Do you also mix in the aileron trim (crow braking ?) ?
Do you use the flaps on take-off ?

Best Regards,
Nicolas.
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Old 04-25-2009, 12:08 AM
  #159
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Default RE: Bvm Bob Cat Build thread!

Quote:
ORIGINAL: SpiderJets

Hi,

I am nearly finished with mine. Hopefully the maiden flight tomorrow.
My BC has the new JetCAT P-80 SE kerostart installed. (with 97N - a bit over 22lbs of thrust)

I am struggling with the flap throw and flap mixer settings, though.
I do not understand the recommendations of the BVM website on this.
Can one of you experts tell me how much flaps you use and how much elevator downtrim you mix in ?
Do you also mix in the aileron trim (crow braking ?) ?
Do you use the flaps on take-off ?

Best Regards,
Nicolas.
Hi Nicolas!
I am not a BC expert yet!
But I reply anyway!!
I don`t use flaps on my first maiden take-off.
But If I will fly on grass fields, I will possibly use take-off flaps.
I used Bvms Recommended full flaps for landing but without mixed elevator,I think i will try some different flaps/elevator mixes, because I have move the recommended center of gravity (20 mm behind the drilled holes)
Good luck with the maiden.[sm=thumbup.gif]

Regards
Lasse P
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Old 04-27-2009, 04:38 PM
  #160
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Default RE: Bvm Bob Cat Build thread!

Lasse, can you comment on how visible the Blue/Yellow color scheme is on your Bobcat? Any problems seeing it against the sky?
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Old 04-27-2009, 04:58 PM
  #161
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Default RE: Bvm Bob Cat Build thread!

Lasse,
I test flew my Bobcat last last week with a P70, i was cautious with my CG setting. Where is yours set and how do you did you find it to fly? and where did you put you ECU and receiver battery(s)?
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Old 05-18-2009, 06:54 PM
  #162
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Default RE: Bvm Bob Cat Build thread!

I'm am just a few days from my maiden flight and wanted to know if you would comment on the control throws of aileron, elevator, rudder? My setup is as follows:

elevator: 2" up / 1.5" down

aileron: 1" up / 3/4" down

rudder: 1" in - 1.5" outboard

I don't have the original manual since I purchased mycomposite BCused, but found the above numbers on the BVM website.

I have added about 15-20% expo to each of the above just because that is how I set upmost of my aircraft.

My first flights will be from a grass runway. How do you feel about using 1/2 flaps for takeoff? I have found on this forum that some required up trim when using flaps, while others have required down trim. I find that odd. Any comments?

Did you use full flaps on your first landing?

What about flight times? Iran my RAM 500equipped BC with full tanks and got about 6 1/2 minutes (at full throttle) before pulling from the UAT. I thought about setting my maiden flight at 5 minutes to be on the safe side.

Center of gravity: is that measured with landing gear up or down?

John
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Old 05-18-2009, 06:57 PM
  #163
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Default RE: Bvm Bob Cat Build thread!



Edited - Sorry, I was being repetitive. 1/2 flaps for takeoff are fine for me, but a little up elevator was required for 1/2 flaps slightly more with full flaps and gear down.

On my P-80, it uses 8oz/minute and I have a UAT, center hopper tank, and 2 saddle tanks. This gives me between 6-8 minutes depending on how I use the throttle. This also allows for a few fly-by's incase I don't like the approach.

Hope this helps!

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Old 05-18-2009, 07:03 PM
  #164
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Default RE: Bvm Bob Cat Build thread!


Quote:
ORIGINAL: JetCatJimmy



Edited - Sorry, I was being repetitive. 1/2 flaps for takeoff are fine for me, but a little up elevator was required for 1/2 flaps slightly more with full flaps and gear down.

On my P-80, it uses 8oz/minute and I have a UAT, center hopper tank, and 2 saddle tanks. This gives me between 6-8 minutes depending on how I use the throttle. This also allows for a few fly-by's incase I don't like the approach.

Hope this helps!

That's where I went to get the info for my original setup. Just wanted to hear from others in the field that it worked well or not.
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Old 05-18-2009, 07:07 PM
  #165
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Default RE: Bvm Bob Cat Build thread!

1" of aileron throw is a lot for my taste, I run less and more expo. BVMs aileron rates have always seemed high to me but the elevators are always spot on.
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Old 05-18-2009, 07:08 PM
  #166
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Default RE: Bvm Bob Cat Build thread!



I was very pleased with the setup initially.  I added a little more down elevator throw in order to improve inverted flying, and have increased the rudder throws so I can practice my knifeedge.  But it still balances on the holes in the booms and everything else is stock.

By the way, I edited my previous post as I re-read yours.

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Old 05-18-2009, 08:20 PM
  #167
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Default RE: Bvm Bob Cat Build thread!


Quote:
ORIGINAL: JetCatJimmy



I was very pleased with the setup initially. I added a little more down elevator throw in order to improve inverted flying, and have increased the rudder throws so I can practice my knifeedge. But it still balances on the holes in the booms and everything else is stock.

By the way, I edited my previous post as I re-read yours.


Jimmy,

Are you checking balance with gear up or down?
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Old 05-18-2009, 08:32 PM
  #168
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Default RE: Bvm Bob Cat Build thread!

I check the CG with gear down and the UAT full of kero, but all other tanks EMPTY.  I'm using A123's all through the plane.  3-cell ECU in the nose and 2 2-cell Rx packs velcroed to the side of the fuse in the rear of the plane.  Much room for adjustments of CG when I have more time to mess around with it.

I'm going to be painting soon and want to compensate for the tailweight the new colors will end up adding.
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Old 06-02-2009, 09:59 PM
  #169
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Default RE: Bvm Bob Cat Build thread!

Jimmy,

Thanks for the tips. I did my maiden last weekend without incident. Used the recommended throws issued by BVM but found the elevator a bit touchy at high speed. Switched to low rate (about 20% less throw) and have left it there for all flight modes.

I used 1/2 flaps on takeoff and full for landing. About 3/8" uptrimprogrammed for half flapsand1/2" forfull flaps. My CG is per the instructions (on the fuselage holes) but plan to move it back soon.

My field is grass and a bit rough in spots. Made 5 successful flights on Saturday but broke two flex plates the following day. Need to work on my landings! I'm using the stock BVM retracts and Duro struts. Have a set of Pro Links on order to replace the mains and hope that will help.

I'm considering a engine upgrade since the RAM 500 takes longer to get to altitude (at take off) than I like. I'm considering the P70 or 80, but a bit confused at the $300 price difference in the two and would expect the larger turbine to cost more. Any comments?

John

Quote:
ORIGINAL: JetCatJimmy

I check the CG with gear down and the UAT full of kero, but all other tanks EMPTY. I'm using A123's all through the plane. 3-cell ECU in the nose and 2 2-cell Rx packs velcroed to the side of the fuse in the rear of the plane. Much room for adjustments of CG when I have more time to mess around with it.

I'm going to be painting soon and want to compensate for the tailweight the new colors will end up adding.
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Old 06-03-2009, 09:26 AM
  #170
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Default RE: Bvm Bob Cat Build thread!

Congratulations!!! Yes, I also broke a couple flex plates on the first couple flights. I really needed to learn to let the plane settle onto the mains. I had a tendency to fly it onto the nose wheel. Now, I just let her glide in at pretty much idle once I'm about 30 feet from the end of the runway. She settles beautifully.

I ended up adding a lot of expo to the surfaces, but kept the elevator throws so that I could do some more aerobatics, but I know what you mean about the touchiness. In the beginning, someone asked if my aileron servos were twitchy because the plane was rocking back and forth at speed. I kinda laughed and told him, no - my hands had been shaking the whole time!!

I don't know the reason for the cheaper price on the P80-SE, but I have my older P80 dialed up to the max which is about 21 pounds of thrust. The new SE seems to have that and a machined compressor wheel for faster response. I would definitely get the most engine for your dollar there! I'm almost at a 1:1 thrust with my jet and I really enjoy its performance!

Once again, great job on the maiden, and your color scheme is awesome. Very bright! Mine gets its paint this week. Wish me luck!

Quote:
ORIGINAL: jthomas235

Jimmy,

Thanks for the tips. I did my maiden last weekend without incident. Used the recommended throws issued by BVM but found the elevator a bit touchy at high speed. Switched to low rate (about 20% less throw) and have left it there for all flight modes.

I used 1/2 flaps on takeoff and full for landing. About 1/8" down trim added for half and a little more for full flaps. My CG is per the instructions (on the fuselage holes) but plan to move it back soon.

My field is grass and a bit rough in spots. Made 5 successful flights on Saturday but broke two flex plates the following day. Need to work on my landings! I'm using the stock BVM retracts and Duro struts. Have a set of Pro Links on order to replace the mains and hope that will help.

I'm considering a engine upgrade since the RAM 500 takes longer to get to altitude (at take off) than I care for. I'm considering the P70 or 80, but a bit confused at the $300 price difference in the two and would expect the larger turbine to cost more. Any comments?

John

Quote:
ORIGINAL: JetCatJimmy

I check the CG with gear down and the UAT full of kero, but all other tanks EMPTY. I'm using A123's all through the plane. 3-cell ECU in the nose and 2 2-cell Rx packs velcroed to the side of the fuse in the rear of the plane. Much room for adjustments of CG when I have more time to mess around with it.

I'm going to be painting soon and want to compensate for the tailweight the new colors will end up adding.
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Old 08-05-2009, 01:05 AM
  #171
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Default RE: Bvm Bob Cat Build thread!

HI TO ALL ,
I JUST FINISHED UP READING THIS ALL THRED REGARDING THE BOB CAT , INCLUDING WATCHING THE VIDIO , GREAT MAIDEN, MUSIC AND PRESANTATION.MY BOBCAT IS MY FIRST JET TRAINER . I HAVE ABOUT 100 FLIGHT , WITH A P-80.
TOP SPEED +- 115 MPH .FLY OF PAVED RUNWAY , BROKE 3 TIMES NOSE FLEX PLATE , AND 5 TIMES ALTERNATE MAIN FLEX PLATS. 2 - FLAME OUT , 1 ECU BATT. FAILER , 1 TURBINE FLAME OUT. AFTER SENT FOR SERVICE - FLOWLESS .
JR 10X SPECTRUM CONVERTION , SPECTRUM 9100 RX 4 SATELIGHT RX . BULLET PROOF . TO THE NEW COMERES EACH LANDING IS DIFFERENT. IT IS ALL PRACTICE , PRACTICE AND MORE PRC.......
THE FLEX PLAT WITH THE TRAILING LINKS ARE GREAT , AND REALY SAVE THE PLANE FROM BRAKAGE . AND TRAST ME I HAD SOME ROUGH LANDING , BUNNY HUMPING , JUMPING AND EVEN LANDING UP SIDE DOWN .THE BOB CAT IS SOLID LIKE A ROCK . MY FLIGHT DURATION IS 7 MIN . SET UP FOR LANDING AFTER 5 MIN . THE OLD P - 80 ARE GAS HUNGRY . I WILL RECOMEND THE NEW P - 80 SE , SLIGHTLY MORE TRUST AND FAST RESPOND .
I LAND WITH FULL FLAPS , UP TRIM ON ELEV , UP AIL ( CROW ) .
IF YOU NEED MORE INFO ( I AM NOT EXPERT , JUST MY EXPIRIENCE WITH MY BOBCAT ) DROP ME A LINE. HAVE FUN WITH YOUR NEW BOBCAT ONE OF THE BEST SPORT JET THAT CAN TAKE P -70 TO P -160 !!! NOT KIDDING.
ISAAC
BTW WHERE IS THE SPELL CK IN THIS FORM ?
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Old 03-26-2012, 11:30 AM
  #172
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Default RE: Bvm Bob Cat Build thread!

Quote:
ORIGINAL: Lasse Palm

Cockpit and Canopy
I make my own Cockpit/Clear canopy!!

Lasse
I really like the detailed Cockpit on your Bobcat. Can you tell me where I can get the plastic instrument panels from ???

Thanks
Paul
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Old 03-28-2012, 01:44 PM
  #173
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Default RE: Bvm Bob Cat Build thread!

Hello Paul!
I used the cockpit interior from Nauwa models in Sweden, they made ​​these cockpit accessories!
But!!
The company does not exist anymore..Sorry![&o]

Regards
Lasse Palm

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Old 03-28-2012, 02:47 PM
  #174
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Default RE: Bvm Bob Cat Build thread!

Why did I just now see this? I even searched a while back. Mine is about halfway done, looking forward to reading this thread.

Mine will be all Futaba Sbus with a P100, should be pretty minimal wiring
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Old 02-13-2014, 08:23 AM
  #175
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Default

What servos are you guys using for the rudders, JR3301 not that common here
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