RE: Nitro models pusher Bobcat?

RE: Nitro models pusher Bobcat? Gallery slideshow

slideshow

View related threads: (in this forum | in all forums)

Logged in as Guest

Users viewing this topic: none

Search This Thread

Printable Version

All Forums >> RC Airplanes >> RC Jets >> RE: Nitro models pusher Bobcat?

Page: << < prev 63 64 [65] 66 67 68 69 70 71 72 next > >>

Login

Message

<< Older Topic Newer Topic >>

RE: Nitro models pusher Bobcat? - 5/3/2007 7:45 PM

Timbba

Posts: 122
Score: 100
Joined: 1/31/2003
Last Login: 2/6/2013
From: Raahe, FINLAND
Status: offline

Check what I received today from Weston-UK for my OS 55AX...

Attachments

Click to see fullsize image.

Click for fullsize

Click to see fullsize image.

Click for fullsize

_____________________________

-FIN 4853-
-Timo Huhtamäki-

Hide Signatures

(in reply to MMallory)

Post #: 1601

RE: Nitro models pusher Bobcat? - 5/4/2007 3:46 AM

AGR413

Posts: 442
Score: 100
Joined: 3/31/2005
Last Login: 1/25/2013
From: Mesa, AZ, USA
Status: offline

quote:

ORIGINAL: Heli-NuBee

I appreciate everyone's input. The tank is installed as shown on this thread with the outlets facing the front of the airplane, the clunk towards the rear and the fuel lines run around the tank back to the engine. I believe the engine went rich, not lean. When I was doing my break-in runs using a tractor prop to keep it cool, the engine had a tendancy to be quite rich in the mid range while set properly at both low and high range. It would quite often load up and quit at about 1/2 throttle. I had adjusted the low range to a point that I thought I had that situation cured but I guess not. We ran the engine for a short time at low rpm before take-off because we were doing a range check before the first flight. I think the engine crankcase loaded up and simply went way to rich at 1/2 throttle resulting in a flame out shortly after take-off. The fibreglass fuselage is severely broken but probably repairable. However, it probably will never be very attractive again. I wish I could just get a new fuselage from Nitro Planes.

Best wishes and good safe flying.

Heli-NuBee (Roger)

Roger,

What prop were you running?

and..you might want to check your low end settings, I have noticed that as far as Idle this engine will accept a wide range of low end needle settings and idle just fine however, you really need to fine tune the low end setting for the transition.

Best of luck, sorry to hear about the crash.

Leighton

_____________________________

If you are flying, life is good.

Hide Signatures

(in reply to Heli-NuBee)

Post #: 1602

RE: Nitro models pusher Bobcat? - 5/4/2007 4:49 AM

Stick Jammer

Posts: 2251
Score: 100
Joined: 11/21/2002
Last Login: 7/19/2008
From: Crete, IL, USA
Status: offline

I do not own any Tower engines but I have to agree with AGR413. The low speed needle setting will affect the mixture all the way up to wide open. They really should give this needle a new name because it controls much more of the throttle curve than just the idle. If your engine was loading up at half throttle, the low speed needle was most likely way too rich. Kinda curious though why you were only at half throttle for takeoff and climb out.

_____________________________

The more you fly, the more you buy.

Hide Signatures

(in reply to AGR413)

Post #: 1603

RE: Nitro models pusher Bobcat? - 5/4/2007 11:56 AM

dragonpilot

Posts: 315
Score: 100
Joined: 2/4/2005
Last Login: 4/20/2010
From: Austin, TX, USA
Status: offline

quote:

ORIGINAL: Stick Jammer

. Kinda curious though why you were only at half throttle for takeoff and climb out.

I was thinking the same thing, maybe next time line it up and go to full and keep her on the ground for another 1-200 feet. Then you'll know whether if she's too rich to take off. Or have someone hold the nose and give a few throttle up and downs to check responses before launch. Don't be too anxious to fly if you're engine isn't functioning properly. Another 5 minutes on the ground can save dozens of repair hours. We've all been there at one point or another...

_____________________________

RCMACHINERY.COM

Hide Signatures

(in reply to Stick Jammer)

Post #: 1604

RE: Nitro models pusher Bobcat? - 5/4/2007 7:33 PM

PointMagu

Posts: 626
Score: 100
Joined: 1/29/2005
Last Login: 5/2/2013
From: Cumberland, MD, USA
Status: offline

Received my replacement canopy in today's mail.

Believe it or not, I got exactly what I ordered...White.

Sorry, P-51MAN

PM

_____________________________

Ah yes, snakes in the cockpit....

Hide Signatures

(in reply to P 51 MAN)

Post #: 1605

RE: Nitro models pusher Bobcat? - 5/4/2007 10:12 PM

GSK

Posts: 291
Score: 105
Joined: 4/4/2007
Last Login: 5/3/2013
From: Hamilton, NEW ZEALAND
Status: offline

Quote

There are no issues with the gear in the stock position. After flying about hundred flights in the stock gear, I installed retracts in the same positions. issues flying with the stock locations you probably have other issues going on.???????

Guess after reading another post of yours re holding the model on the runway for another 1-200 feet I guess the Issues with myself and most flyer's is that they do not have the luxury of having more than a 200 feet of runway to begin with so that Is why I recommend to reverse the gear location. Then you will be able to rotate after 100 feet or less on a grass strip.

Cheers

Hide Signatures

(in reply to dragonpilot)

Post #: 1606

RE: Nitro models pusher Bobcat? - 5/4/2007 10:16 PM

P 51 MAN

Posts: 32
Score: 100
Joined: 10/17/2005
Last Login: 1/12/2009
From: TUSCALOOSA, AL, USA
Status: offline

quote:

ORIGINAL: PointMagu

Received my replacement canopy in today's mail.

Believe it or not, I got exactly what I ordered...White.

Sorry, P-51MAN

PM

Thanks anyway !!!
I e-mailed Nitro about them sending me the wrong color, They gave me a RMA number and said to send them back but they didn't say what they would do about it. So I am going to send them back and hope for the best. I don't know if they will refund the shipping cost to send them back even though they made the mistake but we will see.

Thanks again.

Hide Signatures

(in reply to PointMagu)

Post #: 1607

RE: Nitro models pusher Bobcat? - 5/4/2007 10:57 PM

dragonpilot

Posts: 315
Score: 100
Joined: 2/4/2005
Last Login: 4/20/2010
From: Austin, TX, USA
Status: offline

quote:

ORIGINAL: GSK

Quote

There are no issues with the gear in the stock position. After flying about hundred flights in the stock gear, I installed retracts in the same positions. issues flying with the stock locations you probably have other issues going on.???????

Guess after reading another post of yours re holding the model on the runway for another 1-200 feet I guess the Issues with myself and most flyer's is that they do not have the luxury of having more than a 200 feet of runway to begin with so that Is why I recommend to reverse the gear location. Then you will be able to rotate after 100 feet or less on a grass strip.

Cheers

Cheers,
I was merely suggesting letting a new or troubled engine wind up (and down the runway or strip) for a stretch before taking off that way you may be able to spot trouble before gaining any crash altitude. I didn't think having a 150' runway (1-200 feet) was too much of a luxury anyway but I guess I'm lucky. Model at 0, run down strip to min. 100', rotate...or... 50' runoff room
Don't read too much into that. If you have the stock setup correctly and you're engine is running smooth, there is no reason you can't rotate in 100 feet or less. On the other hand, flying from grass, sounds like your suggestion of reversing the gear may help out with rotation off the weeds.

Beers

_____________________________

RCMACHINERY.COM

Hide Signatures

(in reply to GSK)

Post #: 1608

RE: Nitro models pusher Bobcat? - 5/5/2007 2:06 AM

Stick Jammer

Posts: 2251
Score: 100
Joined: 11/21/2002
Last Login: 7/19/2008
From: Crete, IL, USA
Status: offline

Original: GSK

quote:

Guess after reading another post of yours re holding the model on the runway for another 1-200 feet I guess the Issues with myself and most flyer's is that they do not have the luxury of having more than a 200 feet of runway to begin with so that Is why I recommend to reverse the gear location. Then you will be able to rotate after 100 feet or less on a grass strip.

I have no doubt that with a good power plant this plane could get off the ground in 100 feet or less but landing it on a 200' strip is tricky to say the least. We have 600' of grass at our field and some people can't set down a trainer. At any rate, 200' is awful short to land most planes.

_____________________________

The more you fly, the more you buy.

Hide Signatures

(in reply to GSK)

Post #: 1609

RE: Nitro models pusher Bobcat? - 5/5/2007 2:19 AM

GSK

Posts: 291
Score: 105
Joined: 4/4/2007
Last Login: 5/3/2013
From: Hamilton, NEW ZEALAND
Status: offline

quote:

ORIGINAL: Stick Jammer

Original: GSK

quote:

Guess after reading another post of yours re holding the model on the runway for another 1-200 feet I guess the Issues with myself and most flyer's is that they do not have the luxury of having more than a 200 feet of runway to begin with so that Is why I recommend to reverse the gear location. Then you will be able to rotate after 100 feet or less on a grass strip.

I have no doubt that with a good power plant this plane could get off the ground in 100 feet or less but landing it on a 200' strip is tricky to say the least. We have 600' of grass at our field and some people can't set down a trainer. At any rate, 200' is awful short to land most planes.

HaHaaHa Yep I guess there are a few around, Our grass strip is 160 feet long and It is Ok for the Bobcat the way I have set it up , comes In slow nose high stops in 50 feet or less from touchdown ,
We are having a working Bee today to lengthen it out another 40 metres,,, mainly because th pattern ships and the large scale ships cannot stop In time

Attachments

Click to see fullsize image.

Click for fullsize

Hide Signatures

(in reply to Stick Jammer)

Post #: 1610

RE: Nitro models pusher Bobcat? - 5/6/2007 4:32 AM

robert92679

Posts: 96
Score: 100
Joined: 4/3/2004
Last Login: 7/27/2011
From: Trabuco Canyon, CA, USA
Status: offline

So has anyone seen the Bobcat with the 'retract ready' option? It costs $10 more, but there isn't much other information on the Nitro Models website. For example, anyone know which retracts it's ready for?

Hide Signatures

(in reply to GSK)

Post #: 1611

RE: Nitro models pusher Bobcat? - 5/6/2007 4:40 AM

Wayne22

Posts: 5383
Score: 105
Joined: 4/10/2002
Last Login: 5/23/2013
From: Strathcona county, AB, CANADA
Status: offline

Anyone know what size bolts attach the booms to the wings..I want to switch the plastic bolts for metal. I know it is between 4 and 6 mm....

Thanks

_____________________________

All I ask is for a chance to prove that money can't make me happy......

Hide Signatures

(in reply to robert92679)

Post #: 1612

RE: Nitro models pusher Bobcat? - 5/6/2007 5:14 AM

Stick Jammer

Posts: 2251
Score: 100
Joined: 11/21/2002
Last Login: 7/19/2008
From: Crete, IL, USA
Status: offline

They're 4mm. I found some with a phillips head at my local hardware store. Smart move changing to steel.

_____________________________

The more you fly, the more you buy.

Hide Signatures

(in reply to Wayne22)

Post #: 1613

RE: Nitro models pusher Bobcat? - 5/6/2007 5:30 AM

Stick Jammer

Posts: 2251
Score: 100
Joined: 11/21/2002
Last Login: 7/19/2008
From: Crete, IL, USA
Status: offline

quote:

ORIGINAL: robert92679

So has anyone seen the Bobcat with the 'retract ready' option? It costs $10 more, but there isn't much other information on the Nitro Models website. For example, anyone know which retracts it's ready for?

I'd say send 'em an e-mail or call for more info. If the "Retract Ready" version is as poorly built as the fixed gear blocks, it probably ain't worth it.

_____________________________

The more you fly, the more you buy.

Hide Signatures

(in reply to robert92679)

Post #: 1614

RE: Nitro models pusher Bobcat? - 5/6/2007 9:12 AM

Wayne22

Posts: 5383
Score: 105
Joined: 4/10/2002
Last Login: 5/23/2013
From: Strathcona county, AB, CANADA
Status: offline

quote:

They're 4mm. I found some with a phillips head at my local hardware store. Smart move changing to steel.

thanks SJ, I figured it out, and just finished swapping them out....just waiting for the battery to finish cycling, and a final balance check, and hopefully it will fly tomorrow......

_____________________________

All I ask is for a chance to prove that money can't make me happy......

Hide Signatures

(in reply to Stick Jammer)

Post #: 1615

RE: Nitro models pusher Bobcat? - 5/7/2007 1:45 AM

Wayne22

Posts: 5383
Score: 105
Joined: 4/10/2002
Last Login: 5/23/2013
From: Strathcona county, AB, CANADA
Status: offline

It Flies !!

Windy as heck today, but it was more or less down the runway. It did the leap-into-the-air thing, so I need to lengthen the nose strut. Got it trimmed out and it flies pretty decently (considering the conditions) Rolls are unbelieveable...!!!! The glow plug let go (we found out later) part way into the flight...resulting in a dead stick landing on rough ground three feet short of the runway.... Guess what?? The stock landing gear blocks held.....the only damage was a slightly bent main gear leg.... Easily bent back at the field (too easily, perhaps....) Noticed a heck of a nose down pitch when the engine quit, though....

Second flight went much better, but still getting a nose down pitch when coming off the power...and running out of up elevator.

Running a 46 FX with an APC 10-8 pusher....did not try any full throttle speed runs due to the wind an turbulence, althoug my son did a horrific dive from about 800' but he had the engine at idle...it was smoking when it came low across the field!!

Got a few things to do before the next flight......

< Message edited by Wayne22 -- 5/7/2007 6:21 AM >

_____________________________

All I ask is for a chance to prove that money can't make me happy......

Hide Signatures

(in reply to Wayne22)

Post #: 1616

RE: Nitro models pusher Bobcat? - 5/7/2007 2:55 AM

GSK

Posts: 291
Score: 105
Joined: 4/4/2007
Last Login: 5/3/2013
From: Hamilton, NEW ZEALAND
Status: offline

quote:

ORIGINAL: Wayne22

The only damage was a slightly bent main gear leg.... Easily bent back at the field (too easily, perhaps....) Noticed a heck of a nose down pitch when the engine quit, though....

Second flight went much better, but still getting a nose down pitch when coming off the power...and running out of up elevator.

..................................................................................................................................................................................

Hi Wayne!
So Now you know what I have been going on about and It like all aircraft need a few changes to get It the way you want it to fly
I replaced the Nose and main U/C legs before I even test flew mine as I have had experience with another of that manufactures models. Yes I still have the standard landing gear blocks on mine also after a heap of flights

What I do to get rid of the nose down thing is to have a flight condition set up for landing , As I slow it down and turn onto base leg I bring the ailerons UP about 3/16 -- 1/4 of an inch.. This has the effect of giving it Up elevator trim as It acts like a delta, and you can slow It down for the final approach with a nose High rear wheels first landing . Try It you will be pleased .

Noise has been a problem but after trying a few muffler set ups I ended up with the set up that you can see in the Pic of a previous post of mine . Prop noise Is now the main Issue but I do not think that there Is much I can do about that .

G .

Hide Signatures

(in reply to Wayne22)

Post #: 1617

RE: Nitro models pusher Bobcat? - 5/7/2007 3:10 AM

Wayne22

Posts: 5383
Score: 105
Joined: 4/10/2002
Last Login: 5/23/2013
From: Strathcona county, AB, CANADA
Status: offline

quote:

What I do to get rid of the nose down thing is to have a flight condition set up for landing , As I slow it down and turn onto base leg I bring the ailerons UP about 3/16 -- 1/4 of an inch.. This has the effect of giving it Up elevator trim as It acts like a delta, and you can slow It down for the final approach with a nose High rear wheels first landing . Try It you will be pleased .

What an excellent idea!!!!! Other than mounting the elevator servo in the stab, I didn't make any structural changes, so it is pretty much stock.... I didn't want too much time and effort invested in it, til I got a feel for how it flies........ Now, on to chapter two!!!!

_____________________________

All I ask is for a chance to prove that money can't make me happy......

Hide Signatures

(in reply to GSK)

Post #: 1618

RE: Nitro models pusher Bobcat? - 5/7/2007 4:29 AM

countryshooter

Posts: 50
Score: 100
Joined: 10/20/2005
Last Login: 3/11/2013
From: Clarksburg, NJ, USA
Status: offline

well I think I'm done adjusting my bobcat. In the first photo you can see I added a 1/8" shim on the tail boom and wing and the second photo you can see the elevator is straight with the stab after a flight. my cg is at 9 7/8" and now this planes glides down real smooth and will fly inverted real nice. will have a vid when I can get someone to take it for me. I'm not saying this settup will work for all but it works for me and I'm a happy camper now

Attachments

Click to see fullsize image.

Click for fullsize

Click to see fullsize image.

Click for fullsize

Hide Signatures

(in reply to Wayne22)

Post #: 1619

RE: Nitro models pusher Bobcat? - 5/7/2007 7:35 AM

Pubhi

Posts: 141
Score: 100
Joined: 11/10/2002
Last Login: 8/20/2012
From: yuma, AZ, USA
Status: offline

quote:

ORIGINAL: Stick Jammer

I do not own any Tower engines but I have to agree with AGR413. The low speed needle setting will affect the mixture all the way up to wide open. They really should give this needle a new name because it controls much more of the throttle curve than just the idle. If your engine was loading up at half throttle, the low speed needle was most likely way too rich. Kinda curious though why you were only at half throttle for takeoff and climb out.

I own a tower 75 and use it on my Keecat 65. When I was breaking the engine in, it just did not want to run properly and no one could tune it. So, one day, I just decided to take a couple of turns out of the low speed needle and sure enough, that fixed the problem immediately. It runs absolutely perfectly now and I think its a great engine for the little money you have to dish out.

Hide Signatures

(in reply to Stick Jammer)

Post #: 1620

RE: Nitro models pusher Bobcat? - 5/8/2007 4:25 AM

Stick Jammer

Posts: 2251
Score: 100
Joined: 11/21/2002
Last Login: 7/19/2008
From: Crete, IL, USA
Status: offline

Wayne,
Congrats on the maiden. Where is your CG set at? AGR413 mentioned something earlier about the nose diving problem when power was cut with his CG more than 10.5" but went away when the CG was moved forward to around 10.25".

_____________________________

The more you fly, the more you buy.

Hide Signatures

(in reply to Wayne22)

Post #: 1621

RE: Nitro models pusher Bobcat? - 5/8/2007 6:00 AM

Wayne22

Posts: 5383
Score: 105
Joined: 4/10/2002
Last Login: 5/23/2013
From: Strathcona county, AB, CANADA
Status: offline

Thanks, it is right on 10.5 inches... one of the theories my son and I were bouncing around was to move it back even more because the elevator is not very responsive. I think it is that flat bottom stab causing the inconsistencies, but it seems to be doing the opposite of what aerodynamic theory tells us........

I have to move the engine back a bit...I never accounted for the swept back trailing edge, and the first prop (a bit flexible) smacked the trailing edge. I put the apc on which is a lot stiffer, and it cleared the trailing edge, but not by much.....

_____________________________

All I ask is for a chance to prove that money can't make me happy......

Hide Signatures

(in reply to Stick Jammer)

Post #: 1622

RE: Nitro models pusher Bobcat? - 5/8/2007 10:37 AM

ldzielak

Posts: 1
Score: 100
Joined: 1/2/2005
Last Login: 12/11/2008
From: Campbell River, BC, CANADA
Status: offline

Quick question, if I use the stock servo locations, what length servo extentions does this kit need. I'm thinking like 18" or 24" maybe for Elevator, Rudder and maybe Aileron too. I'm traveling this week and would like to purchase what I need this week, so I can build this weekend.

Thanks,

Lee

Hide Signatures

(in reply to Wayne22)

Post #: 1623

RE: Nitro models pusher Bobcat? - 5/8/2007 10:56 AM

gofastz

Posts: 87
Score: 100
Joined: 12/1/2006
Last Login: 9/24/2009
From: Callahan, FL, USA
Status: offline

Lee,

Don't cut yourself short...Extentions can't be lengthened if you know what I mean....get the 36'' for the tail section...I used 18'' in the wings and it worked out....good luck and don't forget to strengthen the the landing mains blocks.......Mark

Hide Signatures

(in reply to ldzielak)

Post #: 1624

RE: Nitro models pusher Bobcat? - 5/8/2007 11:58 AM

XJet

Posts: 3849
Score: 100
Joined: 3/31/2003
Last Login: 3/24/2009
From: Tokoroa, , NEW ZEALAND
Status: offline

I flew mine on the weekend (ASP (Magnum) 52 with 10x7 prop) and it flew about how I figured it would except...

On takeoff (after lifting off) it wants to climb very steeply, needing about 1/3 down elevator to stop it going vertical. This isn't the "leap off the deck syndrome).

The faster it flies (at full throttle) the more it wants to tuck it's nose down though. If I do a high-speed run I have to use increasing back-pressure on the stick to keep it level -- but once it slows down it starts to climb agressively again.

I'm wondering if it's that lifting tail section providing an increasing amount of lift (thus pitching the nose down) as the airspeed goes up.

Right now it's quite manageable but not a characteristic I enjoy. My CG is about 10.25 inches and it needs a good dose of down elevator to stay straight and level when inverted (indicating to me that the CG could/should go back further).

Did anyone else use the straight piece of wire when fitting the wing? The instructions on mine made no mention of this wire and although the position of the holes for it were marked on the fuselage they were not drilled. I drilled them and fitted the wire because I wanted to have the option of removing the wings rather than gluing them on -- although I'm reconsidering that.

I switched to a 10x8 prop today and noticed absolutely no difference in performance. The RPMs dropped slightly but the speed was identical.

The ASP is pulling (by ear) about 14,000-14,500RPMs with the 10x7 and I'm going to fit an OPS pipe. That ought to liven it up a bit :-)

What I am impressed with is the weight -- it's really light and you can slow it *right* up on the approach for very nose-high touchdowns. However, I've noticed that the elevator isn't too powerful in the turns -- another indicator that perhaps the CG is a little too far forward for my liking.

Just a few more data points.

Hide Signatures

(in reply to gofastz)

Post #: 1625

Page: << < prev 63 64 [65] 66 67 68 69 70 71 72 next > >>

All Forums >> RC Airplanes >> RC Jets >> RE: Nitro models pusher Bobcat?
Page: << < prev 63 64 [65] 66 67 68 69 70 71 72 next > >>

Jump to:

Google

Search | Marketplace | Event Calendar | Local Clubs | Magazine | Product Ratings | New Products | Discussion Forums

Photo Gallery | Instructor Search | Field|Track|Marina Search

Advertisers | Hobby Vendor Resources | Rate Manufacturers | Sign In/Sign Up

SITE MAP! : : FORUM RULES

RC Universe is a service of Internet Brands, Inc. Copyright © 2001-2013.

Charities we support that also need your help
Yorkie Rescue | Humane Society | ASPCA | Crohn's-Colitis America

1.406RCU1