Speedracer2112

I saw the photos. Looks good for vertical shock. Most of the damage is from either a nose wheel landing or landing too fast. Mine usually bends if I run off the end of the runway. I replace the pin after I have to straighten it a couple of times. It depends on how bad a ding it takes. It will break if you bend it back too many times.

[link=http://www.youtube.com/watch?v=A31lDAB3qfs]Nose gear failure[/link]

SR

djstar39

My Feedback: (4)

Yep! That video is a carbon copy of my last flight except I was on grass.

My axle pin has never bent... just snapped clean off. I'll get several from Robarts.

djstar

krproton

Haven't visited this thread in a while - been messin' with other planes. But here's my latest B-25. Did a re cover in a different version of 'Executive Sweet.' Model not finished in pics, but have more done since. Need to finish decal on nose. All MonoKote. Paint is PPG. What is anybody using for wheels these days? Prototypes and my first personal B-25 were flown with Robart's and no problems. But this one, the tires keep coming off the rims. Looked at inserts, but I don't think those will work. It's like the rims are too small for the tires and don't capture the lip around the inside of the rubber. Switched to Sullivan for now.

Tim

Speedracer2112

I use the Robarts. Third set is about worn out on the mains and about six wheels on the front. The only problem I have seen was when my plane ran over a storm drain at the airshow. The wheels dropped into the holes in the grate at high speed and it made them lopsided. I took them apart, cleaned them and reassembled. No problems. I do use the inserts. They help alot to hold the tire together and for shock absorption. You can buy the same stuff at the hardware store for 50 cents.

There is a tire glue that car/truck/buggy bangers use to hold on their wheels. Its a rubberized CA glue. They will never come off again. EVER!!

[link=http://www.bsi-inc.com/Pages/hobby/ca.html]IC-2000[/link]

Tower has several brands also but IC-2000 is rubberized.


I saw you used the stock exhaust!! I LIKE IT! I actually went out and bought the old exaust pipes. Yours looks much nicer. How about a closer look? Any special hardware? OS81A's? If they are 81's, throw on a set of APC 13x7 props just once. It is such a big difference in speed, performance and glide.

Cheers!

SR

Speedracer2112

I land a little different. Full throttle across the back side of the field with flaps down and gear down. Keep in mind my plane is going very fast and is several mistakes high. As she passes me I go to idle. I fly about 100 yards out and start my turn. I keep my nose down at all times! (This prevents stalls. My first bird met this fate.) I use the rudders to keep the nose down in the turn if needed. If you fail to keep the nose down you will spiral in. Comming out of the turn I develope a 35 degree down slope and glide in. I add power if needed. The nose gear video above shows this. If you listen you will hear me add power as she was sinking too fast. Since then I have polished my landings quite a bit by doing touch and gos with my TF Cessna 182. Believe it or not, they land alot alike, just the Cessna lands much slower.

Main thing to pick up here is each plane and pilot are different. "Mustang Fever" helped me set up my second plane BTW.

He is running OS55AX motors, MAS 12x8 props, fixed gear, 18 pounds, a nose heavy CG of 4 1/2" and is a scale pilot.

I am running OS81a motors, 13X7 APC props, Robart retracts, 20 pounds, a nose heavy CG of 4 1/2" and am a "Kamikaze" Pilot.

I do loops, rolls, hammerheads and fly inverted with my B-25. The guys at the field positively hate this. Thus my nickname, "Kamikaze."

Learning to land at idle has a major advantage. Dead stick landings. Loose an engine, no problem. Go dead stick. Go to idle with the other motor and land. Total control with no gyros or fighting a dead engine. If you look at almost every twin crash on YouTube you will see someone fighting a dead engine ending in disaster. Loose an engine go into a death spiral take the other engine to idle, DIVE to pick up speed, land at idle on or off the field and take minor losses vs a total loss.

This is a Left Engine failure with a dead stick landing.[link=http://www.youtube.com/watch?v=8Qu7W-nHMvc]Left Engine Out[/link] Sorry, My kids were chatty!


SR

Mustang Fever

My Feedback: (2)

Speed Racer:

It's all about having fun, aint it? I fully intend to do some mild aerobatics with mine once I get used to it, at least enough so I can fly the fun scale pattern. (Maybe inside loops and wingovers) Currently, I'm still working out the bugs. Ran afoul of the servo mount problem Saturday, and had to fly on one aileron. It was kind of instinctive to just ride the rudders a little harder, so no problem. I did run off the end of the runway - it was too gusty to slow down much and the field was short. No sweat.

I've switched to 12x6 MAS 3 bladers, the engines seem to really like them and run a long time on an 11 oz tank.

After I epoxied the servo mounts for the left aileron, I experimentally "tapped" on one of the flap servo arms, and its mounts let go. Then I went around and tapped on the remaining 4, and they all broke loose. I thought the mounts were a good setup, what with the square hole cut in the plates for the hard wood and the triangle stock reinforcement. Problem is Wong Hung Low don't know how to glue very good. They need to retrain that cat.

krproton

Hi SR.

I'm using the O.S. .72S-a engine. The only special hardware was a carb arm extension for the right engine that one of my buddies turned for me at work. Here's some pics...

Speedracer2112

It is a very common problem unfortunately. I glued mine in real good but I still check them pre and post flight along with my retracts.

It was on about my 150th flight I started to get crazy with loops and rolls. My nose gear had stuck and I was trying to use G forces to get it free. I thought "What the heck", she will be in a million pieces in a few minutes when I belly land, so why not? I did loops, rolls and hammerheads trying to get the gear down. It never worked. I landed on the mains in the grass. Not a scratch on her! Go figure. There is a photo of it around here somewhere.

Loops are easy. I cut the power at the top to keep from tearing the wings off when I pull up. Rolls need to be started at a 30-45 degree incline as you will be at a 30-45 degree dive at the end. Hammer heads, I pull straight up and drive straight into the sky, pull off of the power and tail slide. I dive straight down with the power off until I have control speed and level flight again. Ive only flown inverted once. I got griped out by several club members so I won't be doing that again. The flight characteristics arent that far off from "Real Flight" if you ask me.

SR

Mustang Fever

My Feedback: (2)

After having to straighten the factory nose gear about six times, I ordered a Fults to replace it, the one for 20 pound models that has a 1/4" pivot shaft. The big question is will the plastic nose gear block hold up after I open the hole up to 1/4". We'll see. The current setup is just not working.

norm

Bob, Good luck with the noze gear mount, PM me if you need will send you my fix fear kit as I did not use it.

Servo blocks in the hatch!!!

For the servo mount, I recall in the early postings signaling this problem as the block "dislocate" under vibration and it happened to me in flight (2nd or 3rd) the aircraft was turning on one aileron only, I know the plane is heavy but not that heavy!

I used thin CA to soak all blocks on all hatch; 6 on the main wing and the 2 rudder. I also used 2 sided foam tape (the regular 3/4 inch white 2sided foam tape) to ""stick" the servo to the hatch. What you need to do is paint some epoxy on the hatch where the servo go and place a tape on the servo so it is glued there in place. You then reinstall the screws.

This will be a good back up to the failing blocks if ever it happens again. I always use this safety procedure on all servo hatch since those blocks break under and form whatever reason, they will not take my model down.

This is a cheap, no weight and effective solution.

Hope this help.

Normand

Mustang Fever

My Feedback: (2)

Thanks, Normand. Yeah, turning on one aileron is a little strange, eh?

I just went ahead and epoxied all my servo blocks as I had knocked them all loose already. Did you have any trouble with the rudder servo mounts? I haven't pulled mine out to look, yet, but since I've bumped the rudders into things while carrying it around I'm guessing they'll be OK as they haven't busted yet.

If that plastic nose gear block doesn't hold up to the 1/4" hole and the Fults gear, I'm going to try and make an aluminum block to replace it. I just know I can't deal with the factory nose gear anymore. Another new one would probably just start bending as well, and then it's only a matter of cycles until it fatigues and breaks.

norm

Bob,

I did not have any trouible but as paranoia set in I just went ahead ans glued the rear ones as well. Epoxy is a good glue but has its own propertys and may crack loose again... it is a safe bet to place thge 2 sided tape in there, as it also improves cutting the vibration.

For the rest I hope your plan goes well. I also have a 92" A-26 fix noze gear with a stronger wire gauge fit with an aluminium seat I still have in a the garbage can!, will pull it out tonight

good luck,

Normand

Speedracer2112

I have two sets of the factory fixed gear and you are welcome to them if you so choose.

LMK

SR

djstar39

My Feedback: (4)

Folks,

Replacing the nose gear shear pin that broke on my last landing. Question... should the nose gear scissors face toward the front or back? I've seen pictures on this thread both ways. With the scissors facing toward the rear, it tends to hit the air line attached to the front of the cylinder.

I had it facing forward so I'll probably go that way.

dave

krproton

The oleo scissors on the nose gear is supposed to face the rear of the plane. On the mains, they face forward. The scissors on the nose should not interfere with the air line on the back of the air cylinder, unless your nose gear is bent backward. But if you prefer the nose scissors to face forward, who will notice anyway?

djstar39

My Feedback: (4)

Thanks Tim! Glad to see you still follow this thread from way long ago! Yeah I'm not sure why mine do but when I retract the nose gear the scissors hits the air line. Probably not a problem since the wheel tends to turn one way or the other. Just don't like anything hitting the air line. It's not bent back so go figure.

I never noticed I had it the wrong way before... We'll see what I do this time. When the shear pin gave way, it took the gear door with it and the spring hinges. SR offered to send me a set that he had. I checked Tower and it looked like you would have to order the assembly to just get those hinges. Some others on this thread used regular pinned hinges and rigged up a rubber band on the wood lever. I'm always amazed how folks can find several solutions to any given problem.

Thanks!

dave

Wyoming Cowboy

My Feedback: (13)

My B-25 is still in the box.  I will prob'ly wait to start on it til Fall/Winter as I'd never have it ready in time to get some good flights out of her this season yet.  I want to take my time building this bird.  Anyone think a pair of .90 4-strokes is too much?  Thinking about using "twinsync" with whichever engines I go with.  I'm excited to see this thing sitting on the flightline.

Mustang Fever

My Feedback: (2)

Nah, I think 90 4 strokes would be perfect. After all, they have about the same power as a 60 2 stroke, and I find that with 55 2 strokes in mine, it has just enough punch.

I had no trouble synching my engines by just tweaking the linkage.

Weeso

Wyoming Cowboy

I am building my bird and I installed 2 magnum 90s 4sroke and it is almost ready needs the final settings to do the maiden flight

Speedracer2112

I was flying last weekend and we saw a large dark cloud comming up from the south. Wind was low and it looked like there was plenty of time for a few more flights. Well, we were wrong. Out of nowhere a huge down pour with 40 mph winds with driving rain enveloped the field. I glanced back at the pits and saw my TF Cessna 182 cart wheeling across the field. Four planes were up and all comming down at the same time. What a mess. I landed hard and bounced three times back into the air. It took out my nose wheel and both props. I had to run and grab the plane and run for shelter. I needed to grab my Cessna too so I ran back out. The wind was so hard the planes wouldnt stay down. I lost control of the Cessna again and it went flipping across the field. The storm lasted about an hour. Lightning and all. Overall I made out "OK". Cessna was water logged but in one piece. The B-25 was dinged from the landing and a little wet.

SR

Mustang Fever

My Feedback: (2)

Ouch. Dark clouds come, I run. Thunderstorm 10 miles away, same thing.

Starting doing retract mount reinforcements. Mix of epoxy and milled fiberglass, allowed to settle and form a fillet on each side of the landing gear "box". Only problem is it takes about 2 hours per wing half, as it's necessary to prop the panel up so that the mix will run down into the area where it's needed.

Sorry no pic. Next post. Camera battery is flat.

Ozmodeller

Anyone had trouble with the nose gear doors not closing properly, tried adjusting the rod but when adjusted so that the door closes it has a tendency to break the horn free from the door.

Peter

norm

Reply to all

Guys please insert pictures, it makes subjects interesting and hey, a picture is worth a thousand words!

Normand

Speedracer2112

Here is my "guess." You dont have a air restrictor on your retracts and the pressure is slamming the door into the stops while closing, ripping off the horn. Place a restrictor and it will stop.

If you do not have the restrictor, the door adjustment is easy. You have to take off the nose glass and the plastic bulkhead to do it. Set the retracts into the closed position and make sure it is completely retracted, close the door and screw in the set screw from the front of the plane.

Hope this helps.

SR

Mustang Fever

My Feedback: (2)

Now, here's a nose gear. And no pesky "Doors", either. Weren't they a rock group or something?

I'm now really happy with this bird. When I got done with the nose gear mod, I checked the CG, and man was she nose heavy. Originally, I had put about 15 45 caliber 230 grain bullets up under the chin to get the CG at about 4-3/4". I ended up taking out all but 3 of them, and the CG is now just aft of the recommended 5" point. She flies really, really nice.