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-   -   Top Flite B-25 ARF (Tecnical, tips, suggestions) (https://www.rcuniverse.com/forum/arf-rtf-75/6494380-top-flite-b-25-arf-tecnical-tips-suggestions.html)

Mustang Fever 12-28-2012 09:21 PM

RE: Top Flite B-25 ARF (Tecnical, tips, suggestions)
 
One of the nice things about this bird is that most anything will fit in the cowls, allowing you to turn nice, large scale size props. The only downside I can see is that there isn't a lot of space for big fuel tanks. I had to really cram to get 11oz ones in mine.

And everyone has been right that the bird will fly on most anything. The thick airfoil gives it a very low stalling speed, at a very high AOA. I think if you can get it to move at all, it'll probably fly OK.

Fidelity101 12-28-2012 09:27 PM

RE: Top Flite B-25 ARF (Tecnical, tips, suggestions)
 
I haven't started building yet, so I can't speak from experience...but the stock plane comes with 14oz tanks so how was it hard to fit an 11oz tank? After a LOT of thinking, I've decided to start the build with OS 95v engines. I have 2 OS 81a's and two OS 95v engines. The 95v is exactly 1oz heavier and should spin a 13x8x3 easily.


Mustang Fever 12-29-2012 06:15 AM

RE: Top Flite B-25 ARF (Tecnical, tips, suggestions)
 
I used Sullivans tanks, for reliability, and the 11oz was the biggest that would go in there.

kochj 01-01-2013 08:59 PM

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


ORIGINAL: Mustang Fever

I used Sullivans tanks, for reliability, and the 11oz was the biggest that would go in there.
You could try a SODA or H2o bottles of dif. sizes....
Too bad you can't use IV bags Like I use in my Gas Boat....

djstar39 01-06-2013 05:37 AM

RE: Top Flite B-25 ARF (Tecnical, tips, suggestions)
 
I have a couple of NIB DLE 20 engines sitting in my workshop and there are days when I stare at them and then stare at my B-25 and kind of go back and forth.

I have had a couple of Saito 82's in mine that have been problematic with surging. Horizon Hobby is awesome because when I sent them in for service a couple months ago, they agreed that they were surging and just sent me 2 brand new engines! Pretty awesome after using them for 3 years!!! HH is the best as I certainly did NOT expect new engines!!!

So I have 2 DLE's and 2 Saito's sitting in their boxes with 2 empty firewalls. I'm converting most of my birds to gas so I think I'm going to have to see if there's a possibility here. :D

Mustang Fever 01-06-2013 06:16 AM

RE: Top Flite B-25 ARF (Tecnical, tips, suggestions)
 
Now that's a good problem to have.

RICK9303 01-12-2013 01:16 PM

RE: Top Flite B-25 ARF (Tecnical, tips, suggestions)
 
Is there some thing with Glennis Aircraft? I emailed them twice on a set of wheels and tires for my B25 and got no reponce. Does anyone know of an other place to get scale wheels, other than robart?

Thanks Rick

gregory.aldrich1 01-13-2013 03:12 AM

RE: Top Flite B-25 ARF (Tecnical, tips, suggestions)
 
1 Attachment(s)
I got my scale wheels from Tower hobbies. I believe they were sullivan but I could only get the mains in metal, the nose gear only came in plastic. Hope that helps.
Greg

rcnut101 01-13-2013 05:24 AM

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


ORIGINAL: RICK9303

Is there some thing with Glennis Aircraft? I emailed them twice on a set of wheels and tires for my B25 and got no reponce. Does anyone know of an other place to get scale wheels, other than robart?

Thanks Rick

He is very slow to respond, From what I understand , His days of making R/C stuff is limited. Tires and wheels for this are $275.00

Fidelity101 01-16-2013 12:19 PM

RE: Top Flite B-25 ARF (Tecnical, tips, suggestions)
 
1 Attachment(s)
The included engine mounts say they're good for up to a 70 size engine. I have a couple extra pairs of engine mounts that are designed for the larger OS 95v engine that I'm using...but I will not be able to use the larger engine mounts and still be able to install the engine at the angle listed in the manual. I cut out the four stroke mounting pattern and temporarily taped it to the firewall. Because the larger engine mounts could not be installed at the angle listed in the manual, I decided to go with the stock engine mounts. This required me to cut off the front of the circular portion of each engine mount so I could get the engine as far back as possible. I was able to get exactly 5" from firewall to prop hub.

I'm posting a few pictures of my engine mounts to show spacing with the stock mounts as well as the throttle servo mounts. I did the left engine mount first and the engine sits back about 1/16" shy of 5". The right engine is almost exactly 5" out.

Airnondas 01-30-2013 02:55 PM

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


ORIGINAL: djstar39

I have a couple of NIB DLE 20 engines sitting in my workshop and there are days when I stare at them and then stare at my B-25 and kind of go back and forth.

I have had a couple of Saito 82's in mine that have been problematic with surging. Horizon Hobby is awesome because when I sent them in for service a couple months ago, they agreed that they were surging and just sent me 2 brand new engines! Pretty awesome after using them for 3 years!!! HH is the best as I certainly did NOT expect new engines!!!

So I have 2 DLE's and 2 Saito's sitting in their boxes with 2 empty firewalls. I'm converting most of my birds to gas so I think I'm going to have to see if there's a possibility here. :D
Hi Djstar

I am thinking about putting in two DLE's as well, for one no more oily mess to clean up at the end of the day, how do you think the DLE's will do for power.

Cheers


Airnondas.

Fidelity101 01-30-2013 03:01 PM

RE: Top Flite B-25 ARF (Tecnical, tips, suggestions)
 
People are using Saito 14cc engines which are gas, so if you can make them fit, you'll have some crazy power!

Airnondas 01-30-2013 03:11 PM

RE: Top Flite B-25 ARF (Tecnical, tips, suggestions)
 
Thanks for the info 101

djstar39 01-30-2013 04:08 PM

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

There is no question that a couple DLE 20's would be way more power than this bird needs. But I have them sitting there and will find a way to bash them in. I really am getting away from glow and the mess and the tweaking of the needles, etc. Keep in mind that I had a couple troublesome Saito 82's that Horizon replaced with brand new engines. So my firewalls are currently empty and I've got work to do to either break in the new Saito's, mount them, etc. or daydream about the DLE 20's. Have to see how much clearance a 15 X 7 X 3 prop would leave me. :D

I'll keep you all posted as to how it goes. There's a good possibility that it might be too much hacking to look good.

Dave

Fidelity101 01-30-2013 04:25 PM

RE: Top Flite B-25 ARF (Tecnical, tips, suggestions)
 
I went with os 95v engines, used the stock mounts and recommended locations on the firewall. The engines barely fit and gave me about 1mm shy of 5" from prop hub to firewall...which I can work with.

I read on this forum that many people broke the servo mounts and reglued the arms. I did notice that one of the arms on the right Aileron Servo was easily removable and I glued it with 5 minute epoxy. All four of the rudder servo arms were easily removable and glued back with five-minute Epoxy. The problem I have now is whether or not to replace the arms on the other aileron and flaps. I spent a good five minutes with each arm and was unable to remove them after twisting and turning at every angle. Instead, I used thin CA and covered both arms and allowed the CA to set without using kicker… which would make it Brittle. I have 485HB hitec servos for flaps, 5485 HB servos for ailerons and 5085mg servos for rudder control. Can anyone advise as to what kind of problems have been encountered with the stock glue holding the arms to the servo plates? Has there been a revision which improved the glue used? It looks as though they used the arms as well as triangle stock to secure the arms to the servo plate. I did notice that the arms that came off freely did so after the glue cracked...but it still took a hobby knife and patience to break them loose.

I will not be able to work on it for another day or two, but I am debating on whether or not the thin CA over the stock glue will be good enough… or if I should go back with a heat gun and remove them...which is going to be difficult. I am also debating on going back and putting double-sided foam tape between the servo and the plate in case something does come loose.

I have been skipping around the manual installing servos after finishing everything up to page 13. I am waiting on Robart to send me the electric retracts for this plane. (Going on 4 months now)...else I'd just follow the manual.

Airnondas 01-30-2013 04:41 PM

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


ORIGINAL: djstar39

Airnondas,

There is no question that a couple DLE 20's would be way more power than this bird needs. But I have them sitting there and will find a way to bash them in. I really am getting away from glow and the mess and the tweaking of the needles, etc. Keep in mind that I had a couple troublesome Saito 82's that Horizon replaced with brand new engines. So my firewalls are currently empty and I've got work to do to either break in the new Saito's, mount them, etc. or daydream about the DLE 20's. Have to see how much clearance a 15 X 7 X 3 prop would leave me. :D

I'll keep you all posted as to how it goes. There's a good possibility that it might be too much hacking to look good.

Dave

Thanks Dave for all the great info, and I will looking out for your posts.

Cheers and happy trails,
______________

Airnondas.

Fidelity101 01-31-2013 06:55 AM

RE: Top Flite B-25 ARF (Tecnical, tips, suggestions)
 
Has anyone tried these
http://centuryjet.com/product_info.p...9463de851bd05a

They look very solid, but pricey given they are pneumatic.

Mustang Fever 01-31-2013 11:44 AM

RE: Top Flite B-25 ARF (Tecnical, tips, suggestions)
 
The Mitchell is within the weight limit of HK item 107000061. For $144, I have to seriously consider them. The main wheels are a bit small, 2-3/4", but they would work. I'm going to check the strut lengths when I get home and see if the set will work on the B-25.

They come with servo operated brakes, which I want to have when I fit retracts.

Fidelity101 01-31-2013 02:26 PM

RE: Top Flite B-25 ARF (Tecnical, tips, suggestions)
 
http://www.hobbyking.com/hobbyking/s..._60_Class.html
Are these what you're talking about?

They use a 5mm pin to hold the retract unit to the strut. I wonder if they would hold up as well as the Robart retracts? I would guess not, but they are also about $400 cheaper.

Mustang Fever 01-31-2013 03:05 PM

RE: Top Flite B-25 ARF (Tecnical, tips, suggestions)
 
I think the 5mm pin is kind of standard on retracts this size. Doesn't Robart use the same setup?

At $400 bucks cheaper, I'd try them.

Airnondas 01-31-2013 08:54 PM

RE: Top Flite B-25 ARF (Tecnical, tips, suggestions)
 
1 Attachment(s)
Here is a nice shot at of a B-25 at our flying field where the Club moto is " If it don't have guns then your the target"

Fidelity101 02-03-2013 11:12 AM

RE: Top Flite B-25 ARF (Tecnical, tips, suggestions)
 
1 Attachment(s)
Making progress on the build...the gear doors were installed in the nacelles. I did have one little issue with the black ball links in that the 2mm nut kept binding on the ball link, which caused it to snap after about 5 turns into the shaft. I had enough to finish the build...so I'm hoping the three I broke were extras. :-) Anyone know if the build required more than the 8 needed for the left and right nacelle? If so, where can I buy more...or would some simple JB weld work as an alternative to the nut?

Will attempt to upload pictures below.


djstar39 02-03-2013 11:35 AM

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

Love your picture... probably because I have 3 of those planes. :D I have the TF B-25, the TF P-51, and the H9 P-51 1.50

Dave

norm 02-05-2013 05:09 AM

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

You should use the JB Weld to glue on the door hinges. I fear the epoxy you are using will crack and you may loose a door. The JB Weld adheres much better on metal than the clear epoxy. I built mine back in 2007 ;) and still enjoying it.

I may install the wingspan bomb bay doors in the next fall. For now i'm still busy with the Lancaster...4 engines 4 times more complication...

Also for spare ball link of all sizes check at Tower : http://www3.towerhobbies.com/cgi-bin...ball&search=Go

Just click the link and it will get you to the page.

Hope this helps you

Normand

djstar39 02-05-2013 05:14 AM

RE: Top Flite B-25 ARF (Tecnical, tips, suggestions)
 
Agree with Norman on using JB Weld. Built mine about a year after Normand did and he was a big help to me (all of us)!

Normand, I did the WS Bomb bay doors and the rotating top turret on mine and wrote it up on RCScalebuilder. Had some trouble with the release mechanism but it all worked out. I'm busy building the Wingspan Models 1/9th B-17 so I get the 4 times more complication. :)

Dave



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