norm

Fidelity,

You should clean up your shop! you'll become dizzy with all those things lying around. Do what I say dont do what I doo! It is good to see those tools and parts and boxes and wrapping piling up together around the model, I know I feel as happy as a P__ in S___ when my shop gets like that.

Normand

kochj

Hey Fidelity...

Forget the Tigercat....I see the Thunder TIGER Sea Neptune... (I think that is what is was called) That seaplane is what I flew for my trainer!....O.S. .46FX in the boom.
I learned to fly on Real Flight 2 (they didn't have any 3d in that one) and went
on my Fathers boat, and flew that plane after putting it together myself.....
1st rc plane I ever had, and it flew many flights w/o ever crashing, until I got cocky and I skipped it too hard off a large wave, and folded it's wings...
I even flew that plane in the rain!.... Float flying is a blast...

Apologize for going off topic.

KREAMKARTER

My Feedback: (4)

Hi Guy's
Never Ever tidy up the workshop(sweep the floor maybe) but never clean up! You'll never find THAT THING your looking for!!! LOL
Cheers from OZ
Ps I have the GP B-25 waiting in the wings, 3 other projects in the way first!

KREAMKARTER

My Feedback: (4)

Ooops
That was a Top Flite B-25 not GP, goe's to show what happens when ...a/old age sets in (C.R.A.F.T )Cant Remember A Flamin' Thing!!!!!)
b/ too many kits to work with

Fidelity101

My Feedback: (13)

It's actually a sea master, not a sea neptune. Following the footsteps of B-Squared, I used an OS 55 AX engine for power.

The shop is a complete mess because of the B 25 build. I am really glad I reviewed the manual before starting build and purchased all of the recommended build items. I probably went a little overboard with the items in the build. I used hitec 485hb servos on flaps, 5485hb servos on ailerons, 5625mg for elevator and 5085mg for rudder. The power expander pro board wasnt really needed, but it was a nice to have. The mcdaniels onboard glow 472te was pre configured for 42" leads which was the perfect length. I have decided against using a Gyro as I do not want to add further complexity. The OS 95v fs engines spinning 13X8X3 props should give me more than enough power. Tower hobbies had the Sullivan 14 ounce fuel tank listed as an option for this plane... it does not fit! I decided to use the included fuel tanks with a two line set up.

Does anyone know if Topflite changed the wheels used in this kit? I read some reviews saying that they were just too soft and many people replace them... but the wheels that I have seem fairly rigid. Compared to the Robart wheels I have for my Cessna 310, they are a lot more rigid.

Fidelity101

My Feedback: (13)

Anyone know if a flex pipe is available for the OS 95v engine? I really don't want to cut the cowl in order to fit the stock muffler and a flex pipe seems like the perfect option.

Mark C

My Feedback: (26)

This is for you guy's here in the midwest running OS 55AX engines, what have you found to be the best brand and size prop for the B-25?

raaf

hi fibelity101
i used robart scale wheels [plastic] with inserts into the tyre which makes them much tougher.

cheers mate raaf

kochj

According to the parts compatability: They all use the M11 Header Pipe Nut
What the O.S. 72FS-a and FS81 Alpha use, so can the 95V. Regarding thread sizes.... off the header.

http://www3.towerhobbies.com/cgi-bin...?&I=LXCB22&P=Z
This one will work- stock # OSMG2684 MFG #72108100

And this:
http://www3.towerhobbies.com/cgi-bin...?&I=LXCB15&P=Z

and this
http://www3.towerhobbies.com/cgi-bin...?&I=LXXE97&P=Z

and this
http://www3.towerhobbies.com/cgi-bin...?&I=LXXE98&P=Z

look up the .81fs-A engine and look under parts and when you see the optional parts.... That is where you will see some of the headers, pipes ect....

Hope that helps...

If you can use a header 90deg, or other, so you can KEEP the original exhuast , is a better way to go..

FLEX PIPES ROB power...and they can break if not supported properly.... and are a Real PITA to fix...even with the use of silver solder!...

This may be a option, spendy but will NOT BREAK....
http://www3.towerhobbies.com/cgi-bin...?&I=LXWZH7&P=M

Zoomer02

Is anyone using a power distribution system for your receiver? This plane has a lot of servos in it and I was wondering about dual batteries set ups and other options. Please let me know what you guys are using or does it work just fine on one battery?

Fidelity101

My Feedback: (13)

I purchased the Smart Fly Power Expander Pro for my Hitec Optima 9 receiver. It's probably not needed, but I wanted to have redundancy. If you do a search on this thread, you will see several others who have used the same Expander board with success.

I installed the Expander board next to the servos under the pilots and build a removable canopy using magnets to hold it in place. I'm using 2 2S LIFE 2100mah packs to power the Expander board.

norm

Hi Zoomer,

it all depends on the servos you are using, you must figure out the amp draw; or the milliamp "mah' draw of each servos expected to run simultaenously. If you follow the book, Top Flite suggest the type of servos to be used. Like many you will choose your own so the total "mah" of the 4 flap and 2 aileron and 1 tail servos will draw approximatly 500mah each for a total of 3500mah at peak working load. You are not going to draw that much current since the flaps once deployed will not draw current (2000mah). This is why they specify to use 4000mah to 4500mah nimh battery in this model.

There is now Hi volt servos @ 7.4 v that delivers more power and less amp that can be used with LiOn batteries same weight 5000+mah!

You should not be afraid of the capacity of the receiver to deliver the necessary power to your servos as long as you follow the amp draw rules. You must consider the amp draw to be inferior to your battery capacity by at least 30% specially if you work with 2.4ghz. the higher the amp draw will cause a volt drop critical with 2.4 since it will reset below 3.8v and all the results ....

Hope this help

Normand

Fidelity101

My Feedback: (13)

Great explanation and fairly accurate when dealing with nickel metal hydride and nickel cadmium. Unfortunately, it does not take the connectors into consideration. A typical JR connector is good for 3A constant. You can have a 5000 mAh pack And still have a brown out or battery failure if your connector cannot handle the amperage. On the flipside you can have a 800 mAh life pack and you will be fine so long as you do not exceed three amp constant on your discharge. I know this can get very confusing but the most important parts to consider is the max amperage required to power your servos and how many connectors you have sharing that load. And this is the exact reason that the power expander is used by many people with expensive airplanes.

If you want simple, get a LIFE battery pack with multiple JR connectors plugged into your receiver and you will be fine. If you want multiple redundancy, then use two battery packs of the same chemistry and plug both battery packs into your power expander. The second battery in the system will provide back up should one of the batteries fail. Also, in the event of a servo failure, the power expander will isolate that servo which will prevent the dead servo from dragging the battery voltage too low and causing a complete system failure.

Now that I have stated all of this, it is significantly more likely that you will make a mistake and crash the airplane long before a battery or a servo fails… Providing you were using quality products. I went a bit overboard and used multiple battery packs and the power expander to provide consistent power to all of my servos Because I'm an engineer and I have to over complicate things.

I now have a set of electric Robart retracts and I am looking forward to installing them and getting this plane at the field in the next month or so. I am actually more worried about the soldering job I did on the servo push rods. I got them very hot and used a good amount of solder but it is difficult to tell if the solder went all of the way through and the solder clearly shows on one side of the connector but not the other

Zoomer02

Thanks for the help. I think I found my problem. I am using a 6V - 5000 maH Battery. For the first time I moved up to 6V and was having problems getting some servos and equipment to work when using JR Heavy Duty Y harnesses with my HiTec Optima 9 receiver. I found out that JR and HiTec use different signal voltages where JR uses the full voltage HiTech uses 3 volts for the signal wire. My JR Y harness have a signal amplifier in them like all y harnesses do except it is too strong for the HiTech receiver to work correctly. I was advised to buy HiTech hfeavy duty Y harnesses and it should fix my problem. I am off to the LHS to see it this works. I was thinking it was the long sero leads and the servos not getting enough power and it was the opposite. You think all of these wires are interchangeable and it is not necessarily so in some instances.

norm

Hi Fidelity,

did you put some acid on the rod as well as in the threaded brass sleeve? if not you can clean it and add some paste and reheat this will ensure a throughly covered weld and solid.

Normand

Fidelity101

My Feedback: (13)

Norm,

I did not use soldering paste or flux which is probably my problem. The solder I used had flux built into the solder itself, but I usually prefer to use extra flux when making connectors. Now that they are made and everything is trimmed I am kicking myself for not doing it correctly the first time. I did take all of them off the airplane and twist and turned the connectors to try to break them free and there was no give or movement. I think I will just bite the bullet and go back and re-solder all of the connectors just to be sure... Using flux this time. :-)

Thanks for the tip and I will be sure to post pictures before my maiden flight. I also plan on having pacoflyer perform the maiden flight as my nerves will be shot.

Fidelity101

My Feedback: (13)

Hitech servos are pretty much the only servos I use... and I have never used an amplifier. As long as you're using quality connectors you will be fine... but avoid ever using an amplifier with those servos.

Zoomer02

The amplifier is built into every Y harness out there. The problem only occurs when the system is using 6V or greater with a HiTech receiver and non-HiTech Y harness. Evidently the HiTech Y harness has a smaller amplifier built into it.

Fidelity101

My Feedback: (13)

Where did you hear that every Y harness has a built-in amplifier? I admit that one of the few things I buy in bulk from Hobby King is servo extenders and Y harnesses. They are relatively cheap at $.50-$.75 per unit With quality wiring and quality connectors. With that being said I have dissected several of the Y harnesses as well as hitech wire harnesses and there is no electronic circuitry. At the very least, an amplifier would have some type of circuitry whether that be a printed board or actual individual components. I have some amplified y harnesses and they are clearly fat and have circuitry in the middle.

From everything I have ever read about hitec servos, they do not like amplified connectors. I am curious to see where you got this information about "every Y harness has an amplifier" as I do not believe that is correct... and I have purchased multiple y harnesses from multiple vendors over the years. A "amplified" harness is generally more expensive

Zoomer02

Ok so maybe all don't have a amplifier, buffer or booster at the $0.75 level. I stand corrected. The point of my post is that not all y-harness are the same and can be a source of problems on a model such as this. I would refer you to this link: [link]http://www.rcgroups.com/forums/showpost.php?p=9648539&postcount=4[/link] Also there is a good write up on the Aurora 9 when using a Smartfly power expander. [link]http://www.rcgroups.com/forums/showpost.php?p=15715822&postcount=8791[/link]

Speedracer2112

Hi Folks!

Small story. I took my B-25 to Joe Nall this year. I flew her about 5 or six times. On the last takeoff, I noticed an extreme left hand rotation that I corrected with right aileron and up elevator and came around to take a look. On a pass, both motors were running but I was still holding off center controls. I climbed slowly and thought about trimming out but then decided to land instead. I passed by again and dropped my gear. Still struggling in the turns and unable to go full throttle without yawing to the left I dropped into the pattern to land. After landing the left motor slowly came to a stop on taxi.

Long story short, the motor was dead the entire time and was free spinning backwards. I made three complete rotations around the field on one motor. [X(] On examination the exhaust valve spring was broken.

I never used the rudder.

Shes passing 500 flights. This plane truly loves me.

Speed

ronbell

Wow - glad you were able to bring her back in that condition.  Really builds confidence as to what a solid girl she is.

chris923

My Feedback: (53)

Speed,What kind of engines were you using? I am on my second TF B-25, the 1st one with OS 70 surpasses. The 2nd one with JBA 15 gassers.

Speedracer2112

I'm running OS81a's. Great little motors.

Speed

umitv

My Feedback: (15)

Finally I replaced os .55's with dle 20's on my b-25. It flies great. Only problem is prop clearance. 14x9 3 blade prop only 1,5 inch from ground. I'll post some pictures