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

Hi All,

Reading the post on 3 blade props MAS 12x8 3 blade not sure what engines these were for. Can anyone recommend 3 blade using the OS 70 surpass.
Ray

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

The MAS 12x8 three blades were recommended on the 70 SurpassII

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

Hello Flycast,

The MAS 12 x 8 3 blades on a OS70 spin @ +/- 8500 rpm and on the Saito 82 @ 9700 RPM. The plane flys great with the MAS 12 x 8 3 blade on a Saito 82. As Tim (Krproyton) recomends, the 12 x 8 3 blade MAS is nice and scale but recomend to Maiden the plane on 13 x 6 APC 2 blade. I am also of this opinion since you need all the torque and power you have to lift off the ground when "unfamiliar" with its habits.

The OS 70 reports 1.1 BHP @ 11,00o rpm. You do not have 1.1 hp @ 8500 +/- 500 rpm with MAS 12 x 8 3 blades!!! your power is much less. Saito claims 1.5 HP @ 11000rpm and the power is not all there @ 9700rpm. You should try the MAS 12 x 6 3 blade on the OS70 and see if you are in the neighbourhood of 9500 +/- 300RPM. You will increase the torque on those props when lifting this 22 lbs +/- 1 lbs off the ground on the first flight.

See post 412 on page 17

I would go with 13 x 6 APC with the OS70 for the maiden, will give you speed & torque until you get used to it...which will not take long. It flys great.

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

(Thanks Normand!). [sm=thumbup.gif]

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

Here's a few photos of the work I've been doing on my TF B-25. In here are the following:

The glow fuel bolt holder for the cowl bolts.

The lack of space between the carb and mount when prop hub is 5" from firewall.

The "before" photo of the canopy screws.

The "After" photo of the canopy screws (and all the other screws too) after painting them with TF Monokote matching OD paint.

An overall shot of the plane (see the "other guys" B-25 in the background?)


Overall weight is 19 pounds 2 ounces with a large 5 cell 2400 maH battery and a second larger air tank plus Robart wheels.

My OS 70's turn MAS 12-8 3 blade props at 8890 RPM

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

do as i did make a scale bomb bay and a hatch there for the lipos. they will be on the cg then. That way you can go for a scale cockpit

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

Dick are the the one I purchased so many Pettit products from in the 70's and early 80's been away for a while.

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

Nope, not me. That was Pettit Paints, makers of HobbyPoxy.

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

Thanks Normandouellette & P39 for recommendations with prop.I'll go with the 13x6 APC for starters.
Your info is very much appreciated.
I'm going to be busy this Christmas just bought the Topflite Beech Staggerwing from LHS the B25 is arriving this week from "Doug O'Brian Hobbies"Londonderry NH
Being across the "pond" from you guys this forum has been great for someone like myself having read all the posts on the B25 reading the original faults with the kit (wing alignment etc.) from the early builders hope the "mods" have been sorted when I get mine, and things like the retract wood arms being a little suspect, Mike Krug as kindly posted a pair off to me.
Thanks to all
Ray

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

Good luck! I've been having a blast putting mine together. I'll be glad when I get off the nacelles. Lots of work there with motors, retracts, servos, tanks, cowls, lg door covers.... I suppose that's why it's first in the "good book."

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

Re the magnets to hold bits on, if you dig through your Dremel accessories you'll likely find a grinding cylinder same diam. as magnets. That way you can cut really perfect cylindrical, flat-bottomed holes to Zap the magnets into. Mike-RC's look very neat so suspect he uses similar technique?

No-one had a go at weathering/detailing the flat Monokote finish yet?

Cam

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

you can add all scale rivets. go to flitemetal.com and look at a product called rosie the riveter. read all about it. panel lines from 1/64 chart tape and matt krylon finish holds it all on. electric = no fuel proofing

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

Great site...Very helpful for the finishing of a B-17 1/9th Wingspanmodel. Hopefully someone will come out with an Avro Lancaster 1/9th or 1/12th would be ideal.

For Our B-25 my Maiden was made on the week-end and already 3 members from our club have it on order.

Please timothy do not remind me of fuel proofing, My B-25 takes no less than 1 hour cleaning up @ the field! without counting the time for final clean up at home. I hate cleaning the dishes...reminds me of those christmas gathering and drying the dishes for hours when I was a kid...I'm traumatized! No I will never trade my 4 strokes for electric NO.

thanx for the info

Normand

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

its a mess /I still fly a couple glow engines in biplanes and its a mess. Hane you heard of the sound systems they have . Im not talking ram either. these have the sound from start , idle full power and back to off at the control to your throttle. They use actual recorded engine sounds.


wingspan will be my summer build! 1/9 scale the 1/6 is too big

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

Could be wrong did anyone on the B25 build substitute the nylon hinges for Robarts on control surfaces I've always preferred Robarts using "Gorilla glue " it expands and dispels the air in the slot but sometimes can be a bit messy if too much is applied.
Seemed to have read somewhere been back and forward reading the posts.
Sorry Tim this question as been a reply to your post in mistake

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

Just browsing over the instructions (still awaiting for kit - all the retracts, motors, pilots etc have arrived:)) and was checking out the elevator linkage. Whilst I don't doubt the plane has been well designed/tested, I'm a bit dubious about 2-56 hardware and the "hope the solder's good" torsion bar horn arrangement on a 20lb twin - not alot of redundancy if either lets go.

I'd much prefer twin elevator servos/horns with 4-40 hardware on a plane of this size/weight/expense.

I'd normally consider putting dual mini servos in the tailplane with separate horns in each elevator half, but would be reluctant to cut into the lower sheeting considering there's a couple of whopping great fins hanging off the ends!

Has anyone else had similar reservations? Made modifications?

Cam

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

Cam,

Use a Z bendder on the servo horn and the plastic clevis on the aileron/flap horn. They are very good and do not suddnenly break like the metal ones. Trust it. The soldering is useless and never as safe as a "Z" bend.

Never use Gorilla glue on the hinges, follow the instructions. I did mine with 3 hr epoxy and put petrolium gelly around the hinge in the middle to protect against thr glue. add glue to the tip of your hinge. this way with 3 hr glue you have plenty of time to make them.

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

Are you saying that you trust that flimsy little plastic pin in the middle of the plastic clevis any more that a perfectly good solder joint?

On the use of Robart hinges, there is probably not enough material in the control surfaces for a Robart hinge to glue onto.

Three hour epoxy on CA hinges, I certainly hope not. Isn't that why they call them CA hinges?

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

Why not Gorilla glue it sets rock hard fills the joint/slot and as long as you smear vaseline or light oil on the pin no problem. I've used it for many years although it's not suitable for some applications.
Guess we all have are own preferences.

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

Yes, on a pin hinge, Gorilla Glue is OK, but I thought Norman was speaking of using it on CA hinges.

Personally I use Pacer Hinge Glue on pin hinges. Very easy to clean up and they set up quickly.

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

Guys,

Awesome how UPS works well!!!

My kit left Illinois on Nov, 11th and it's scheduled for delivery here in Rio, Brazil, today!!! Is it fast or what??

Flavio

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

For the price you paid for shipping, they should have delivered it in a Lear Jet!

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

Pettit,

I think he was referring to Hinge points.

Flavio

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

Pettit,

You've got that right! And the Customs taxes will be 1,000.00 Reais, meaning around 600 dollars... The whole thing cost bout 1,650.00 dollars. But the good thing is: UPS takes care of all the bureaucracy concerning paying the taxes, getting stamps, taking copies, more stamps, signatures, etc... and deliver directly to my door.

BTW, I'm really looking forward to your review... :)

Flavio

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

I never mentionned CA hinges. Gorrila glue expand and may cause the hinge to freeze. Also for the application of the solder clevis, it does not beat the Z bend in a wire.

For hinging the B-25, I cleaned the holes with a matching drill size and applied 3 hr epoxy with a leftover rod and applied glue to the hinge arm then glued it together. It gave me plenty of time to adjust the middle of the hinges and line them up perfectly on the wing. This is the way i've done it. There may be numerous other ways, as long as it is well lined up and that the surfaces move freely it is good.

I am also looking forward to your review.

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

My misunderstanding completely. I had been working on both the Top Flite B-25 and the Hangar 9 B-25 at just about the same time.

One uses CA hinges, the other uses point hinges, and I guess I got them mixed up.

But I like Pacer Hinge Glue on point hinges anyway. A lot less messy.

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

Flavio,

I'm happy to hear you are geeting your plane today. No matter how much you spent for it, like you say this is the way it is down there and it is only money. I have spent approximately 600$ heating my home and garage up here to work on this plane, and this is the way things are up here. I maidened my B-25 in -4 degree ( 27 f) so enjoy the sun and your B-25. congradulation!

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

Yor're right there nothing beats a good solder joint Personally I only use silver solder on my clevis's needs good heat. (Heat with gas runs beautifully into the joint).
Some people prefer to "wick" thin CA into the hinge. Haven't heard of pacer glue, Dick, I'll see if anyone sells it over here and give it a go.
Norman, that's why because of the expansion you have to use a little Gorilla glue keep the pin clean and greased. Does it get that cold in Canada to freeze the pin!! only joking

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

Hi Mike,
Got the arms today, very nice and many thanks.

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

Hello Flycast,
That was fast! I didnt know mail got to the UK so quickly.
I will be going to Austria/Germany and be back 11/26. If anyone else needs arms I can setup and make a few more when I get back. I have the CNC program and a fixture now, so it will be easy to make more. Just send an email to [email protected] and I will take care of you when I get back.
I am sure there are alot of people out there who are building the plane, but have no idea about this thread and have broken levers. So Tim krproton, how about you put an addendum in the kit with my paypal info?:D:D

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

Hi Mike
Just sent you an E mail about the arms, please put me down for a set. I have been trying to get hold of you for a week or so, you must be a busy man !
Regards
Alan

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

Hello Alan,
I have been replying to you. Your internet service must be blocking me or something. Just paypal $12.00 to [email protected].

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

Hi Mike
Payed via Palpal
Thanks
Alan

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

Guys,

It's here!!! The box took a lot of damage on the transport and arrived kind of humid... Don't know why... And hopefully there will be no damage to parts... Otherwise, it will be hard to get a replacement.

Take a look!

Flavio

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

I would never use a plastic clevis on any control surface for the B-25. They will get brittle and break. Seen it happen many times.

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

Normand,

Exactly... One of the most important things in life is to balance your expectations in order to be happy in your life.

So, that's the way things are up there and down here and... that's where we belong... :):) There and here. And we have to live with those limitations.

You told me to enjoy the sun and I tell you, I usually enjoy it diving, and it makes me real happy! But I could complain, though, since I also love skiing and we don't have any snow in Brazil. Skiing for me is as expensive as buying a B25... 3 times more in Europe and 2 times more in US and Canada (where the best snow in the world is - over the Rockies).

What I want to say is: you can choose between keep whining and complaining or enjoy life as it is and the way things are for you.

Charles Darwin once said: "the survivors are not the most intelligent or the strongest. Are the ones that adapt"...

C ya!

Flavio

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

Flavio, I will be thinking of you while I am skiing in Austria next week!

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

hey does anyone know if the tail gunner sat back there or did he lay down on his stomach? i think his was sitting, but not sure.

let me know, thanks
dan

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

Guys,

Do you recommend mounting the vertical stabilizers to the horizontal stabilizers with epoxy as well as the screws.

Thanks

Alan.

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

Alans

For your stab and vertical fin look @ post # 178 on page 8.