kochj

Well,
I finally found a option to my quest to placing gas engines in this aircraft....
These have been out for a couple of years, but I had forgotten about them....

The plane can no doubt handle the added weight of these engines..... As a smaller gas tank (like half the glow size) will reduce the wet weight.

I think that this is a very viable option, as the Zenoah 20Ei, is just too large, and require too much modification.

Justin

flyingchef

My Feedback: (93)

Well! I haven't look at this tread for about two month and it is going strong, glad to see so many involvement with the TF B25. I had put mine aside while an other project nedeed to be completed but now I am back on it. The plane is fiberglassed with .75 oz, a plug was made to mold a straffer version nose and this now completed I am ready to install the part on the plane. Two large scale hatches will open to give access to power switches and eigh detailed guns. There is a lot of potential with this plane and glad to see so many taking advantage of it.
Bruno

camdyson

First Problem!

Was wondering why the 1" caphead screws retaining the wing panels were so reluctant to screw in despite the pre-drilled holes in the joiner bars seemingly lining up with the holes in wing panel. Further investigation revealed the holes in the wing panel are WAY off centre in the fibreglass tubes - one passed through almost at the tube edge (I inserted screw fully to see where it went, without rods in). [:@][:@][:@] Screw was never gonna go through the joiner coming in at that angle![>:]

At this stage it looks like I'll have to fill the loles in the wing panels with epoxy/glass filler, then re-drill the holes at correct angle. Might even add brass tubes so the holes don't open up over time - you had that problem didn't you Normand?

Has anyone else struck/solved this problem?

Cam

norm

Cam,
I'm still debating if I should glue the inner wing panel to the fuselage. I try and review why this should be taken apart in the future. Glueing the inner wing panel will add strenght and avoid further deterioration of this joining system. Do not forget the wings are heavy with the motor retracts...and vibration. The added weight of the fusetage twisting against the tube joiners and the wings seems to be too strong for the joining in this area. It looks like it is the weak link there. Your problem is a little one since the tube line up the wing and the screw prevents it to come out. Easy fix. By working on the wing you should notice it loosened up since the first time you put it together. I wonder if anyone else have noticed that. I think that if I get only one feedback that someone noticed this, I'll be mixing 30 minute epoxy tonight.

The real problem I noticed is the servo hatch, the blocks break off. Anyone took time to remove their servo hatch and check the blocks following their first few flights?

Normand

Greg2102

Normand,

Had a friend over yesterday who is putting together a Great Planes RV-4. That plane has roughly the same setup for the servo hatch and block. He had glued and screwed his servo blocks cause he thought they were a little weak.

I'm only at the glue the aileron and flap stage of the build but, on my B-25 I think I am gonna take them outside and saturate them with CA and then put a little fillet of Epoxy around the joint where they join the hatch cover.

By the way, I got my first Saito 82 yesterday and the Perry pumps are on the way from Omni Models. Can't wait to figure out how to mount these engines. 1.5 hp apiece, power to spare.

Greg

norm

gerg,


You wont be sorry with those 82's. The plan to reinforce the blocks is perfect. I did the same when putting them together with ythin CA only. They still broke off, maybe the torque effect is higher then the blocks can hold. I in addition added 2 sided foam tape between the servo and the hatch in case the block break off to maintain control. For the pump follow this set up system proposed my the mfg. http://www.perrypumps.com/Pump%20and...s%20System.pdf



normand

timothy thompson

My Feedback: (1)

well waiting on more rivet material and the weather for a maiden. i have all my lipos so all i need is warmer wx. michigan is bad the next 2 weeks. i really dont want to fly with lipos in the 30s and low 40s when is the wx going to break

camdyson

Been 35-40 here too, celcius...

Solved the wing alignment bar issues, epoxied the tubes into the wings. That way if I ever need to replace an inner panel, I'll just saw through the bars at the root and replace panel and bars.

There's a scam in Australia at present with people ripping up copper wire from the railway signals and shipping it to China as scrapmetal. Hope the crooks don't see the wiring going into this B25[X(]

Cam

norm

Cam,

This is the best idea fo the problem I adressed. It seems that most of the loose is in the wing around the tubes and not through the fuselage. i'M MIXING EPOXY TONIGHT!

Normand

kochj

Crack heads have been ripping out Copper pipes from low income housing homes right out of the wall for years!
I suppose this will only increase now......
Watch out to all that have apartments and rent out!!!

Justin

MLDELARUELLE

Hi,
Could someone give the length of robart legs ?
I think mains is 130 mmm
But I don't know for the nose gear
Thanks
ML

timothy thompson

My Feedback: (1)

GOD I WANT TO MAIDEN THIS BIRD! TEMPS IN THE 30S FOR THE NEXT 10 DAYS ALL DURING MY SPRING BREAK! IM SICK OF MICHIGAN WEATHER.SHES A LECCY SO I CANT TAKE THE LIPOS OUT KIN TOO COLD.NEED AT LEASE A 50 DEGREE NO WIND DAY.

sgoen

My Feedback: (5)

I got an email this morning that the brakes from Robart are on the way and should be here today. I may get time to finish the plane in the next couple of weeks. The weather is starting to warm up. I think it is almost time to go flying..............

norm

Well Well Well, Tim,

You never mentionned before that electric set up needed at least 50 degrees! (LOL) My glow engines work at -10 degree, uncomfortable but they work!!!

Nevertheless Tim, this "permafrost" we have is still going to be here until May and that is really $#!^^@.

Hopefully we will hear more from everyone on this thread maidening their planes soon.

Meanwhile I do with it!

Normand

camdyson

Hey Norm,

What squadron flew ski-equipped Corsairs?

B25 is progressing slooowly. Wing joiners are all sorted - I've ended up epoxying the alignment tubes into one side, screw into other, so can still disassemble. If start to get sloppy, will epoxy the lot later. Gyro is set up on rudders - seems to give a bit of "grumbling" in the servos on any gain setting other than off, but seems to work fine.

My new air compressor for my airbrush is hopefully due next week if my birthday hints pay off , then I can get into the scale detailing.

I still haven't found an alternate scheme incorporating those white fuz stripes - anyone have any leads?

Cam

norm

Hello Cam,

About the gyro inducing that grumbling noise, it is normal. You should set it up so it is 100% on and off on your aux 2 switch. Also induce 20% rudder in the aileron to rudder mix, will help in turns.

About the corsair on skis, I' m so bored in the winter I do anything to have fun... i shove skis on lots of my plane>>>I'm not alone!!!! I still have a 22ft th high pile of snow in front of my house. This is a record year in Montreal for snow accumulation. Lats year we were flying at the field since the 10th of March, we expect the snow to melt by mid May this year. meanwhile...

Normand

fytrjok

My Feedback: (2)

Here's a link to the video of my TF B25 and Clark's H9 B25 flying formation at Chatfield State Park. We're practicing for the "Warbirds Over Denver" event coming up June 13, 14, and 15. I'd love to hear your comments and hope this inspires you guys to build on of these and come join the fun!!![sm=spinnyeyes.gif]
http://www.youtube.com/watch?v=hY3zMsfv-vg


Doug

MLDELARUELLE

Great Video ! Perhaps, in my humble opinion, you fly too fast. What are the engines ? Do you fly flull throtle ?


On the other side, I need help about the retracts.
I've mounted Eurokits retracts. They fits, but I have a problem for closing the traps with the legs.

If there is no traps and lever, the retracts retrats (!) well.
If I set the lever, the leg push the lever, but not full movement , except if I set the speed retract using the valve to 100%.
In fact, the spring to expand the retract is very strong in Eurokits, so the force inducted by the air pressure is not strong enough to close the retract.
I've tried with 3.5 bars of pressure in the tank. Which pressure do you use ?

I would like to know if there is a similar pb with the Robart's retracts ? And how to solve it ?
Does anyone tried another way to close the gear doors ?

Thanks
ML

norm

Shows you are in thin air they seem to fly faster at least 20% faster.


nice video, I'll be the small plane in june here, 3 of my buddies built the ziroli 101 inch wingsapan

Normand

camdyson

ML,

I've found my retracts need a fair bit of pressure, so can't slow them down much with the Robart valve. I put 120 psi in and get 8-10 cycles using the large air tank, but up and down with a "clunk". Will try to slow the speed as they loosen up a bit.

Setting up radio today, used the servo speed on the JR PCM 9xII to set 2 sec on flaps and 3 sec on bomb bay doors, and finally worked out how to get the elevator mix to move slow with the flaps - looks cool! Also set some "toe-out" on the rudders to help in an engine-out, not that I plan to have one you understand.

Back to details.......

krproton

About retracting the gear,

I prefer the gear to retract rather fast, making sure they have enough momentum to close the doors on the way up. Extending the gear, you can slow them if you like. Either way--especially on the way down--the gear does "clunk." About the only way to cure that is to slow the gear considerably. And the gear does break in after a few flights.

Fytrjok, nice video!!! That thing should land slower, but maybe because of your altitude...

Tim Lampe
Hobbico R&D

Bill Giulian

My Feedback: (38)

Tim. Am I doing something wrong or did I miss a posting. Just finished putting the landing gear doors on one nacalle, however when I put the nacalle on the wing the gear side door hits the landing gear struct and will not close. Can't see how it is possible to close whitout trimming part of the gear door. The gear is in the full locked down position and I centered it when installing as per the addendum. Help me out please. Thanks, Bill Giulian.

Bill Giulian

My Feedback: (38)

Tim. Please forget about my last post. Never did retracts with retracting doors like this and after the post it dawned on me that when the wheels go up the doors close so that will take care of the problem. Sorry about that. Bill.

MLDELARUELLE

Hi
Thanks Tim for your confirmation.

On the french thread, we have this idea to make the doors move softer. Did someone try something like that ?

ML

fytrjok

My Feedback: (2)

ML,
Believe it or not, most of those passes were done at 1/2 throttle or less! I'm using the recommended OS Surpass 70 II's with the MAS 12 x 8 three bladed props. It's not quite as fast as the H9 with the same engines. I'm sure that the video also makes the planes seem faster than they really are in person. As far as the retracts and gear doors go...I installed the Robarts and I'd recommend hooking up each gear door separately to it's respective bell crank end. That way, you can check each door side during gear operation for linkage binding and fit. It's obviously very important to have reliably operating gear and doors or you're in for some repairs. When everything is set properly it works smoothly and consistently. If it doesn't seem right it probably isn't!! I first disconnected the doors and checked the function against only the bell crank. It needed a little grinding before the binding issue was solved. Then I hooked up the outsind door and found that the pushrod was just a little short and would put too much pull on the bell crank. After some adjustment, the gear retracted and extended as if it were operating without the door mechanism. I did the same check with the inner door (by itself) and found its pushrod also needed some tweaking. Now, everything works so well...I love it!! I did have to fabricate some new bell cranks out of aluminum...the stock ones were just a bit fragile, even after hardening them up with some thin CA.
Hope this helps!

Tim, I was wondering if a little more flap would help??

Doug