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PLANE JIM 10-27-2007 08:38 PM

RE: Top Flite B-25 ARF (Tecnical, tips, suggestions)
 
great flying day in Texas-cool @70 degrees and clear blue sky with a 12 mph wind from the north -How good does it have to get!!!!!!!!!

p39 10-27-2007 08:42 PM

RE: Top Flite B-25 ARF (Tecnical, tips, suggestions)
 
Texas.... ahh..... I'm planning on coming down for the IMAA winter ralley again this year. Well, Next Feb/March. I was down for two years in a row at Edinburg.... oh, it was about 2-3 years ago and flew for 4 days. It's worth the drive. I won't bring my '25 though- not without some flights on her. And Tim- I appreciate the hints and tips....

Iceman 29 10-27-2007 08:58 PM

RE: Top Flite B-25 ARF (Tecnical, tips, suggestions)
 
Tks Tim for the prop-hubs. May be, i can re-machining the original set, i have to compare the diameter.

Concerning the CG, have you seen any differences concerning the flying characteristics when the Landing gear is Up and Down?

javascript:void(opener.AddText('[sm\=50_50.gif]',''));self.focus();


Pascal.

A picture of my last favorite plane , a Curtiss Hawk P6E (great planes), a great flyer, very nice to fly with, is like a trainer ! 30cc Saito on board, javascript:void(opener.AddText('[sm\=thumbup.gif]',''));self.focus();

http://images2.hiboox.com/vignettes/4307/88pjfl3v.jpg

kochj 10-27-2007 10:33 PM

RE: Top Flite B-25 ARF (Tecnical, tips, suggestions)
 
1 Attachment(s)
RCV60-SP would be awsome ..
No valve covers sticking out!!!
The only concern would be that of the sound of these engines,,, They are a bit geary sounding....
Other than that though.. It would swing a large prop.... 2-blade 16x12 or a 3-blade 13x13 or even a 4-blade 14x11
Not sure what would be scale though....
Hmm more I talk about it, the better it sounds...
but again, almost 300$ for one engine and I start to back peddal
The light weight no fuss os 70's sounds like a good engine to place in it... Only issue is the abc CONSTRUTION....
This is a concern for Minnesotans, as in the winter it gets quite cold and that would ruin a non-ringed engine becaseu it would never reace optinum operation temp. and never expand the cyliner walls enough to let go of the piston,.........

Justin

KenVC 10-27-2007 11:01 PM

RE: Top Flite B-25 ARF (Tecnical, tips, suggestions)
 
Hi Tim (krproton)

I am one of those that didn't receive their plane with the first order. My LHS claims they called Top Flite and was told the order has been held up due to decals and won't be available for a few weeks, possibly Dec. Is that right? I am scheduled for major surgery just prior to Thanksgiving and was hoping to work on the B25 then but it sounds like it won't be shipped for quite some time. Can you shed any light on this?

krproton 10-27-2007 11:35 PM

RE: Top Flite B-25 ARF (Tecnical, tips, suggestions)
 


ORIGINAL: [email protected]

Tks Tim for the prop-hubs. May be, i can re-machining the original set, i have to compare the diameter.

Concerning the CG, have you seen any differences concerning the flying characteristics when the Landing gear is Up and Down?

Hi Pascal.

Don't notice much difference in this bird with the gear retracted or extended. She's got a pretty wide C.G. range. We do instruct in the manual to check/set the C.G. with the gear down as this is the way we came up with our figures and tested our model. Also, some of you may not install retracts so again, that's why we specify checking the C.G. with the gear down. [sm=49_49.gif]

timothy thompson 10-27-2007 11:39 PM

RE: Top Flite B-25 ARF (Tecnical, tips, suggestions)
 
well im cutting the bomb bay tommorow got the corsair doors done

krproton 10-27-2007 11:43 PM

RE: Top Flite B-25 ARF (Tecnical, tips, suggestions)
 
Hi KenVC.

Sorry you didn't get a B-25 from the first shipment. The deal is that right now we have the second shipment waiting in our warehouse. I believe the quantity is about the same as the first shipment, so when those kits are released that should fill any remaining back orders. The hold up, (again) is with the decals. New decals should be in this week and as soon as those arrive and get inserted (probably all within the same day!), the kits will be released. So, I think your B-25 should get to you in a week or two at most. [sm=thumbs_up.gif]

I'll try to remember to check in again and let everybody know when those are released.

Good night everybody. I'll check in again tomorrow (between flying (hopefully), mowing the lawn (maybe), football (watching on TV) and ice hockey (in my rec. league).[sm=redface.gif]

Tim

norm 10-28-2007 06:40 AM

RE: Top Flite B-25 ARF (Tecnical, tips, suggestions)
 
Hello Tim,( Krypton), I have been through most of the planning and some building but so far, all is left to do is finish...I see the end...in a few days. I followed your tips at the begining of this thread and found when working on the noze, that it is easyer to fit the bottom part permanently and make the noze gunner greenhouse canopy removable only. I do not have pictures at this point but it is a very simple process. aligning the bottom canopy and the top one with tape and securing 4 screws to the bottom part onto the fuselage. You then remove the greenhoused canopy and you test fit the noze gunner cabin details. Once you secure the details, (I used two sided tape) You notice then that there is an approx gap og 1/8 between the detail contour and the bottom (chin) part. I placed ribbon self adhesive velcro between the two parts to secure the surrounding of the bottom part. Also between the two parts it is possible to glue scrap 1/8 ply so you can screw in the top part greenhouse canopy to the front sides. Using six of the #2 3/8 buttonhead screws. i fasten the canopy , 4 screws to the fuse and two to the sides in the joint with the bottom part. This way the fitting of the noze is always "on the noze" and makes the whole assembly sturdier. I have to learn how to insert pictures and will send some this week.

Also by doing this process, it is very windy here in montreal and my 7 year old girl came running to tell me the witch hat had flew away! Running to the emergency, I dropped the greenhouse canopy and cracked the front. (still holds in one piece but for the ones who knows me, I have a professional malformation that every thing must be impeccable, mechanically and esthetically) Tim are the parts available yet? TOPA1715 ? And since you have a priviledged position (if you have the info) they say it is an assembly, what does it include?

Also "E-power Tim" if you read this, i'm very interested in making a cut out for bomb bay doors like you are doing and I'm maybe not the only one! If you can I would like to know how you proceed, if you need to cut through the formers and how you reinforce. If you can make sort of a step to follow description. I would appreciate.

Thanx guys, I'm going back to the dunjon!

BTW ths B25 from Top flite is a 5/5, nothing deceiving, really nothing deceiving!

flaviosi 10-28-2007 06:43 AM

RE: Top Flite B-25 ARF (Tecnical, tips, suggestions)
 
Bonjour, Pascal!!

Welcome to the non-Shakespeare Club! :)

Flavio

KenVC 10-28-2007 08:25 AM

RE: Top Flite B-25 ARF (Tecnical, tips, suggestions)
 
Tim,

Thanks so much for keeping us informed. Your help and updating is second to none. It would sure be great if all mfr's. of models would do as you have done on your own time!

timothy thompson 10-28-2007 08:53 AM

RE: Top Flite B-25 ARF (Tecnical, tips, suggestions)
 
1 Attachment(s)
well ill go thru a step by step cut today. first pic is the uncut fuse. NO WRINKLES AT ALL UNBELIEVABLE

krproton 10-28-2007 09:23 AM

RE: Top Flite B-25 ARF (Tecnical, tips, suggestions)
 
Good morning.

Thanks Ken.

I can't take too much thanks for the time I have spent answering questions on this site. I have worked on many projects at Hobbico, but for some reason I am suddenly very enthused about this B-25. I guess I have just "fallen in love" with this plane and am very interested to make sure everybody has as much success and enjoys it as much as I. So you see, it is out of joy, not dedication or duty that I am writing here, so it is play not work. Our computer is downstairs where our television is and where my wife, my step-daughter and my self spend much of our time, so all I have to do is walk over to the computer during a TV commercial or when they are doing homework (my wife is a teacher at the local community college) and it takes little time away from our time together. Like right now, my step-daughter is watching TV and my wife is making coffee, so they are "doing their own thing" right now anyway and I can still be in the same room. But I have also promised to cook some bacon, so I better get going!

And right now, everything is easy and everybody is happy, but I hope it remains this way when more people are building their B-25s and begin flying them! [sm=drowning.gif]

I'll check in again later! [sm=cool.gif]

Tim

timothy thompson 10-28-2007 10:24 AM

RE: Top Flite B-25 ARF (Tecnical, tips, suggestions)
 
1 Attachment(s)
reinforced sides with hard balsa now installing rear bulkhead.both bulkheads in now going to put the scale floor in

timothy thompson 10-28-2007 11:21 AM

RE: Top Flite B-25 ARF (Tecnical, tips, suggestions)
 
krypton what is the large opaque tube for? i need to remove it for the bomb bay. so far perfect conversion. The hinge line is low so the fuse is very strong! I sanded the bulkheads and remeber the wood will be covered with sheet styrene all scaled out .




tim put those spider screen savers on and you will get more time

p39 10-28-2007 11:41 AM

RE: Top Flite B-25 ARF (Tecnical, tips, suggestions)
 
The tube is for running the servo wires.

timothy thompson 10-28-2007 01:00 PM

RE: Top Flite B-25 ARF (Tecnical, tips, suggestions)
 
ok ill find another route. This construction will allow a 100% SCALE bay with no structural problems im even adding the longitudinal stiffners they field added to the sides of the fuse

sgoen 10-28-2007 03:07 PM

RE: Top Flite B-25 ARF (Tecnical, tips, suggestions)
 
I have to tell you, after reading this forum I would like to get this kit, but I am very concerned/scare about having a one engine quit problem. I have been in flying for over 25 years, but never had a twin. I would sure hate to loose a plane like this. Any ideas. I was planing on putting in the OS 70 4 stroke engines. How much of a cost difference would it be to go to electric over gas?

p39 10-28-2007 03:10 PM

RE: Top Flite B-25 ARF (Tecnical, tips, suggestions)
 
If you read the forum you'll remember that the plane was designed with that problem in mind. There was a few messages about adding a gyro and all, but it really isn't needed. you just have eto learn a few simple "rules" if you have an engine out- just don't turn into the dead engine.... land right away. Use rudder. The engines are much closer together on this bird and that helps loads.

rcmorrow 10-28-2007 03:23 PM

RE: Top Flite B-25 ARF (Tecnical, tips, suggestions)
 
Timothy, looks like very nice work on the bombay doors ! Looking forward to seeing your progress over the next couple days.

I was able to email Glennis Aircraft (makers of very fine scale wheels for r/c aircraft and related craft). They have a set of wheels (4" mains and 1 3/4" nose wheel) available with or without brakes. Looks like they are a bit pricey ($255 wheels only, $400 with brakes), but they are really an amazing company for scale wheels.

I also know of others using the Robart wheels and foam inserts inside for giving strength due to the wieght of the finished B-25.

Just wanted to share this information if anyone was interested. The website for Glennis is:

www.glennis.com

I am looking into purchasing the wheels, without brakes I think, but I'll have to consult the bank account. If I get them I'll put some photos up here for everyone to see the wheels.

Best to everyone.

timothy thompson 10-28-2007 03:42 PM

RE: Top Flite B-25 ARF (Tecnical, tips, suggestions)
 
1 Attachment(s)
heres more pics

p39 10-28-2007 03:47 PM

RE: Top Flite B-25 ARF (Tecnical, tips, suggestions)
 
The Glennis wheels in my opinion are way too "over scale" for this model. The Robarts should look just fine in my opinion. If I were doing a Ziroli '25.... yes, then the Glennis wheels would be a must. I'm looking to get this done and fly the heck out of it as a fun airplane... not necessarily a knee knocking piece of art.

Looks like the bomb bay is coming along nicely.

norm 10-28-2007 03:53 PM

RE: Top Flite B-25 ARF (Tecnical, tips, suggestions)
 
About Gyros..The Top Flite B-25 has been designe to remain controllable with one engine out. I'll say again that in the worst scenarios, you may be surprized by an engine out. If you look at my posting # 10 (I think) it self explains. For the gyro, the immediate effect on the aircraft when an engine quits, is that the aircraft "Yaws" towards the engine that is out. That means the aircraft abruptly whants to turn to the dead engine. This action can be immediately controlled by adding a gyro on the rudder. The gyro is overridden when you play with the stick so do not worry about a gyro. The gyro only acts as a stand by watchdog for this sudden yaw. If the Yaw is not controlled right away, the aircraft will enter a spiral dive and fly out of control to its doom.

Now if that scenario happens at 300 feet (without a gyro), you cut the throttle and you fly it in like a dead stick ( normal classic procedure) and you may even gain back control by controlling yourself the correct input of rudder and ailerons! Like all of you may know, this scenario never happened when you crashed a plane... So why make your life difficult if you may buy an insurance of 150,00$ which will more than likely bring back your model. The gyro acts as a Yaw damper and makes the correct input at any time you move the ailerons. I have tried it and and testing this system on model twins, I am not only pretending that it may work...it works plain and simple. Also about emergency procedures on full scale aircrafts, it is a standard procedure to go full throttle, control the yaw with the rudder anf maintain wings level with the ailerons then fly to the closest field to save your life. Planes are planes and fly like plane. Do not be fooled by the macho in you. Think of it, when GPS did not exist, we still found our way but now we have it why not use it! make your life easy and stop worrying about twins...enjoy the sound and the beauty of this B-25. I'm a warbird lover so nothing better could have happened to me this last week!

norm 10-28-2007 04:38 PM

RE: Top Flite B-25 ARF (Tecnical, tips, suggestions)
 
(E-power)Tim, you impress me! It seems like we are still honeymooning with our B-25 and there you have to complete the scale functionability and rip open your model!. I still have a channel available...now I know what it will be used for!!! This is a neat job and the pictures explains everything. I will be closely following your hinging system and the door open and close system. Will it be air cylinders? I might just install a "T" on my brake system and add an air valve to actuate the bomb bay doors. Modeltech has a bomb drop system for 2 to 24 bombs. I will instal the 6 bomb system . If you look into this, you may hide your batteries with scale bombs that works! (only fall out). Nice job you have done so far.

norm 10-28-2007 04:43 PM

RE: Top Flite B-25 ARF (Tecnical, tips, suggestions)
 
TiAbout bomb release system, it is not Modeltech. It is Wingspanmodel.com and it is an electronic release system. sorry!

timothy thompson 10-28-2007 05:39 PM

RE: Top Flite B-25 ARF (Tecnical, tips, suggestions)
 
1 Attachment(s)
well here are some better ones a little detail

timothy thompson 10-28-2007 05:41 PM

RE: Top Flite B-25 ARF (Tecnical, tips, suggestions)
 
my lipos are going in but I can stll detail the inside as far as driving air seems easy but ill look at servo too first i have to encase the balsa wioth this styrene . Then i detail the styrene. Hinger I havent even thought about but ill post everything. Remember use a new razor saw and outline the area in blu masking tape it helps guide the saw. I used several layers. dull the adhesive by taping it to your leg a few times that way it wont pull the monokote up

krproton 10-28-2007 06:16 PM

RE: Top Flite B-25 ARF (Tecnical, tips, suggestions)
 
sgoen,

welcome aboard the thread.

Start from the beginning of this thread and read posts about tuning engines and other things about flying twins. There is no way to get around it, no matter what, an engine-out scenario is something you want to avoid, but there are precautions you can take to keep this from happening. And should you find yourself with an engine out, in most cases, all hope is not lost. Just do some research reading through these posts to begin with.

Tim

timothy thompson 10-28-2007 06:22 PM

RE: Top Flite B-25 ARF (Tecnical, tips, suggestions)
 
:DE POWER:D

flaviosi 10-28-2007 06:29 PM

RE: Top Flite B-25 ARF (Tecnical, tips, suggestions)
 
Sgoen,


I have been in flying for over 25 years, but never had a twin. I would sure hate to loose a plane like this. Any ideas.
I'm as concerned as you are. I'm going electric to reduce the odds.

Flavio

flaviosi 10-28-2007 07:12 PM

RE: Top Flite B-25 ARF (Tecnical, tips, suggestions)
 
Guys,

May we talk a little about electronics here?
I'm planning to use Smart-Fly products like the SUPER REG and POWER EXPANDER SPORT

What do you think?

Flavio

norm 10-28-2007 07:16 PM

RE: Top Flite B-25 ARF (Tecnical, tips, suggestions)
 
Sgoen,

Go gow go electric but go glow! The OS 70 has a fabulous sound, My heart was for the 70 but I had a pair of 82's. There is no reason for a glow engine to stop. The main reasons for an engine to quit is a wrong set-up. Everything from the tank to the muffler has to be perfect. Engines don't go dead for no reason. All info's are there in the instruction book; just read, understand and follow the instructions and you should have no dead stick. You must know an engine specialist (ask a guy who fixes his own engines and makes no mystery about it...) and they will set your engine; specially if you tell them it is for your new B-25, they will line up! Once an engine is tuned, you should never but rarely adjust the settings. There are some peripherals you can add for added ease of operation and will increase reliability. The first is a glow driver, for the B-25 the MCD472TE (twin engine glow driver) from Sonic-Tronics (McDaniel) You should order it directly from Hank @ Sonic-Tronics. I know wholesalers don't offer it. it goes for about 125$ and will keep the glow plugs on. Various set up may be made but for the B-25 you whant to set it to go on when you are 20% power and less, it goes on automatically and will not use an extra channel. The added feature of the glow driver eliminates the need of "plugging your glow igniter" (when you start the engines) and drill a huge ugly hole in your cowl to start your engine. You may also install a pump; this will maintain reliable and constant fuel flow. For a twin you cannot use the oscillating pump but you may use the "VP30 Perry pump", +/- 30$ on each engines. This is overkill but if you are a maniac, it is another system to add on your model and the main advantage is you can go "straight pipe" no more muffler pressure and you eliminate an ugly protruding muffler with a small hole on the side by a pipe sticking out by about 1/4 inch.

Enjoy the sound of your 4s glow engines, by all means!

timothy thompson 10-28-2007 07:54 PM

RE: Top Flite B-25 ARF (Tecnical, tips, suggestions)
 
you cant help it if a glow plug goes. even new ones go. why the resistance to e power

flaviosi 10-28-2007 08:00 PM

RE: Top Flite B-25 ARF (Tecnical, tips, suggestions)
 
Timothy,


why the resistance to e power
I agree, but only if you can add some sound simulation... This bird with no sound would be a waste...

Flavio

norm 10-28-2007 08:40 PM

RE: Top Flite B-25 ARF (Tecnical, tips, suggestions)
 
Electric systems are not flawless!!! batteries go dead...wrong connection... Electric systems has its own list of problems begining by controllers... All in all both electric and glow has their own myth..."electric systems are flawless" is a myth and not true, as well as "glow engines go dead" is also a myth and not true. Electric main feature is "clean" and glow main feature is the "sound". Electric motors performs well and batteries got smaller and delivers impressive amount of power. Glow engines are facinating work of art and produce great sound. Our positions on power questions shows well that there is a market for both electric and glow/gas. It all depends on how you feel about it and what you beleive. I often joke about electric but it is a great system and I envy those who fly electric at the end of the day while I clean off the greasy oil all over my models. I know blondes are good looking but I love my brunette! This is what it boils down to. You should not base your power plant choice based on myth but on personal preference and what excite you. Remember this is a facinating hobby and it is fun.

Flavio for electronic set up and for the previous thread, I suggest to install a match box for the flaps. It will be impossible to match the 3 position precisely without it. Do not take the chance to switch on flaps and watch your plane behave unexpectively. this is a simple setup. match the servos at neutral; normally position 1, ie: 15 degree flap mechanically by adjusting the clevis and have the same throw on each flap. then position 0 (retracted / no flaps) will be adjusted with the "match box" to adjust the up stop position equally. Then you switch to position 2 and adjust the down flap (approx 25 degree from the chord line of the wing) andadjust the servos through the match box equally then save your settings by switching the match box dial to zero. The instructions are only a few paragraphs and well explained. As far as electronics this is my best suggestion.

good night guys and keep up the good work!

KenVC 10-28-2007 08:50 PM

RE: Top Flite B-25 ARF (Tecnical, tips, suggestions)
 
McDaniel cueently has the twin engine unit on sale for $105.00. These are the best glow drivers I've had.

norm 10-28-2007 09:11 PM

RE: Top Flite B-25 ARF (Tecnical, tips, suggestions)
 
I agree with you

timothy thompson 10-28-2007 09:21 PM

RE: Top Flite B-25 ARF (Tecnical, tips, suggestions)
 
match boxes are the way to go on the flaps. if i use air to open my bay doors ill need a small seperate air supply

flaviosi 10-28-2007 09:24 PM

RE: Top Flite B-25 ARF (Tecnical, tips, suggestions)
 
Norman,


Flavio for electronic set up and for the previous thread, I suggest to install a match box for the flaps. It will be impossible to match the 3 position precisely without it. Do not take the chance to switch on flaps and watch your plane behave unexpectively. this is a simple setup. match the servos at neutral; normally position 1, ie: 15 degree flap mechanically by adjusting the clevis and have the same throw on each flap. then position 0 (retracted / no flaps) will be adjusted with the "match box" to adjust the up stop position equally. Then you switch to position 2 and adjust the down flap (approx 25 degree from the chord line of the wing) andadjust the servos through the match box equally then save your settings by switching the match box dial to zero. The instructions are only a few paragraphs and well explained. As far as electronics this is my best suggestion.
This is great tip for us all!! You're talking Jr's MatchBox. Chief has a twin pack for 109.95 and I've ordered mine. I'm jus wondering (maybe you could help) if it allows Futaba J connector or only Jr's...

Thanks again, Norman!! And I yet say YES to Smart-Fly products I mentioned above.

Flavio

norm 10-28-2007 09:44 PM

RE: Top Flite B-25 ARF (Tecnical, tips, suggestions)
 
Yes the JR matchbos will work on your futaba. You may also use a matchbox for the 3 servo connected to the rudder. Not that it is critical but because the matchbox also enables you to power separately this "bundle of servos" . I know I will connect a separate battery to power the 4 flap servos and the 3 rudder servos. I am setting up 4000 mah NiMH on the receiver and a second 2700Mah NiMH with a "Y" to power the 2 matchbox. 6 volt! You take away the taks of powering 7 servos away from your receiver.


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