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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)

pettit 11-08-2007 01:15 PM

RE: Top Flite B-25 ARF (Tecnical, tips, suggestions)
 
Hey guys. I got a round piece of dark Monokote in the decal package.

Where does it go?

Under the ball turret?

norm 11-08-2007 01:22 PM

RE: Top Flite B-25 ARF (Tecnical, tips, suggestions)
 
1 Attachment(s)
Yes the round piece of black monokote goes there in the turret but not explaned in the booklet.

pettit 11-08-2007 01:24 PM

RE: Top Flite B-25 ARF (Tecnical, tips, suggestions)
 
OK, thanks. Finally something to write a "Jeer" about....

alans 11-08-2007 01:34 PM

RE: Top Flite B-25 ARF (Tecnical, tips, suggestions)
 
For all those that put the engine at 127mm and had cut the cowl it is possibe to pack out the cowl to make it look half decent. if i had not fitted the throttle servos etc i would of moved the engine back !!

krproton 11-08-2007 02:41 PM

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


ORIGINAL: alans

I think I am around 25% complete, see picture of how far the engine sticks out if you set it at 127mm as per instructions, should it stick out this far. This is how i plan to mount the sensor for the twinsync, i will of course be painting the supporting wood. Excuse the dodgy pictures !!
Alan, I don't know why your engines stick so far out of the cowl. I think you may have your cowl positioned too far aft? If you haven't alrady glued your cowl to the cowl ring, can't you simply slide the cowl forward? I think 1/4" to 3/8" should do it for you.

Tim

krproton 11-08-2007 02:45 PM

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


ORIGINAL: alans

For all those that put the engine at 127mm and had cut the cowl it is possibe to pack out the cowl to make it look half decent. if i had not fitted the throttle servos etc i would of moved the engine back !!
Alan, see my previous post. Also, if you are using O.S. Surpasses, I believe, at the 5" [127mm] prescribed in the manual, your engines are already about as far back on the mount as they could possibly go. The carburetor interferes with the mount, so you can't move the engines any farther aft anyway. Just move your cowl forward on the cowl ring before gluing it on (if it's not too late).

Tim

mike-rc 11-08-2007 02:57 PM

RE: Top Flite B-25 ARF (Tecnical, tips, suggestions)
 
Hello Alan,
In a previous post I mentioned that the distance should be 4-5/8". You cannot glue the cowl rings on with the cowl at the correct distance behind the prop at 5".
Hello Normund,
I mailed your levers out a couple days ago. I look forward to your flight report!
Mike

pettit 11-08-2007 03:01 PM

RE: Top Flite B-25 ARF (Tecnical, tips, suggestions)
 
Mike: Oh yes you can, and I did.

And the engines are mounted 5" away from the firewall.

The front of the cowl is about at the same position as the back of the prop drive washer.

mike-rc 11-08-2007 03:11 PM

RE: Top Flite B-25 ARF (Tecnical, tips, suggestions)
 
My cowl ring was located where the cowl flaps are at 5". I had to shorten it to get past the angle.

norm 11-08-2007 03:18 PM

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

On Oct 29 (page 8 #180 of this thread) not only you triggered everyone's urge to finish their model but you wrote this:


ORIGINAL: krproton

Hey everybody.

Two more flights on my B-25 after work today. I wanted to re visit how the plane flies with the APC 13 x 6 2-blade props vs the 3-blade props I have been experimenting with. To bring you up-to-date, I experimented with several 3-blade props and settled on the Master Airscrew 12 x 8. But as we did all of our testing during development with APC 13 x 6 2-blade props I wanted to do a back-to-back comparison.

Well, the APC props do have more pull and fly the plane faster, but not by a great amount. I'm going to stick with the MAS 12 x 8, but you do get a little better performance out of the APC 13 x 6. One of our test pilots from R&D happened to be present after work when I was flying (who was the primary test pilot for the B-25) and he says the same (actually, it is I who agrees with him!).

We figured the best way to explain it is to strongly recommend using the APC 13 x 6 2-blade props for the first flights and until you have complete confidence in your engines--if one should quit the little extra pull you get will help. But overall we like the MAS 12 x 8 3-blades for appearance (when the model is in the pits) and they are also quieter-definitely.

And oh yea, for those of you who haven't read previous posts about all my prop testing, all this is with O.S. .70 Surpass IIs.

See ya!

Tim



Hello Tim (KrProton)

What RPM did you get with the 13 x 6 APC and what RPM do you get with 12 X 8 3 blade Master airscrew on the OS70 ?

Jon Wise 11-08-2007 03:47 PM

RE: Top Flite B-25 ARF (Tecnical, tips, suggestions)
 
Mike, did you get my check? Did my levers go out as well? Thanks Jon

krproton 11-08-2007 03:48 PM

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



Hello Tim (KrProton)

What RPM did you get with the 13 x 6 APC and what RPM do you get with 12 X 8 3 blade Master airscrew on the OS70 ?
Hi Normand.

I have the data right here in front of me, but I never posted it. Here is what I have;

APC 13 x 6 - I was getting about 10,440 RMP
MAS 12 x 8 3-blade - I was getting about 8,600.

I have decided to stay with the MAS 12 x 8 3-blades.

By the way, the Graupner 12 x 8 3-blades pulled the RPM down to about 8,200. Frankly, I don't know if this is too low of an RPM or not, but it just "seems" low and the plane performs well with the MAS 12 x 8 props and no better with the Graupner's.

There you have it!

Tim

timothy thompson 11-08-2007 04:14 PM

RE: Top Flite B-25 ARF (Tecnical, tips, suggestions)
 
im doing a scale turret and am hand building the guns i show you one soon. im dealing with my cat and hes more important then flying

mike-rc 11-08-2007 04:22 PM

RE: Top Flite B-25 ARF (Tecnical, tips, suggestions)
 
Hello Jon,
Yes, I got the check and mailed the levers yesterday.
Hello Tim Thompson, Are you still going to paypal for a set of levers? I only have 1 pair left now.
Thanks, Mike

Jon Wise 11-08-2007 04:30 PM

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

timothy thompson 11-08-2007 07:15 PM

RE: Top Flite B-25 ARF (Tecnical, tips, suggestions)
 
mike no because im going to do a scale door sequence. those doors were closed when the gear was down. Just found out

flaviosi 11-08-2007 09:12 PM

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


Yes, I got the check and mailed the levers yesterday.
Just to let you know that they arrived here yesterday! Great piece of work!

Thanks a lot!!!

Flavio

norm 11-08-2007 09:50 PM

RE: Top Flite B-25 ARF (Tecnical, tips, suggestions)
 
How the &%$$ did Flavio get his levers in Brasil b4 me in Canada...We are only walking (ok long one) distance away from Montreal. Montreal - NewYork, 15 - 30 bus / day, 25+/ flights / day and I still did not get mine! Is'nt Port Washington on the Island?

mike-rc 11-08-2007 10:04 PM

RE: Top Flite B-25 ARF (Tecnical, tips, suggestions)
 
Hello Normund,
Get a paypal account!
Mike

norm 11-09-2007 12:02 AM

RE: Top Flite B-25 ARF (Tecnical, tips, suggestions)
 
Yeah I always lag...

norm 11-09-2007 12:45 AM

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

Hello Tim (Krproton)

I have just figured out the CG problem I had earlier. Mabe pass the word around since I'm not the only one changing the "foam" wheels. I have installed 4 inch Sullivan wheels. They are much heavier and the same in the front 2.75. Now from 5 inch cg with gears down, my cg moved aft 1.25 inch! waqy more then 1/2 inch. So inconciously when you said setting up the CG @ 5.5 inch with gears up is the way to go with a different wheel set-up. To convince myself, I switched to the 3.87 inch foam wheels and the 2.87 noze wheel. the cg moves aft by less then 1/2 inch when gears up.

For now at least I'm convinced that the cg should not go too far behind when actuating the gears..

Do you think it is advisable to check the CG @ 5.5 inch when using the Robart retracts and a different/heavier set of wheels? When I add brakes on this the CG will again move back....that should not be?

Thank you for your attention


timothy thompson 11-09-2007 01:04 AM

RE: Top Flite B-25 ARF (Tecnical, tips, suggestions)
 
WELL I TOOK MY HALF COMPLETED 1000 LB BOMB TO HOBBY LOBBY TO FIND A END FOR IT. tHEY CALLED THE POLICE AND I HAD TO SHOW THEM THIS SITE TO GET OFF **** HOBBY LOBBY(CRAFT STORE). I USED CLAY MADE A END PIECE AND BAKED IT LOOKS NICE PICS TOMORROW/ HAD TO TAKE CARE OF MY PARAPLEGIC CAT TODAY

timothy thompson 11-09-2007 01:19 AM

RE: Top Flite B-25 ARF (Tecnical, tips, suggestions)
 
im using glennis wheels

alans 11-09-2007 02:41 AM

RE: Top Flite B-25 ARF (Tecnical, tips, suggestions)
 
Hi Tim
I could not move the cowl forward as i was right on the angle at the back of the cowl, i will have to pack the cowl out slightly to compromise.

krproton 11-09-2007 07:53 AM

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


ORIGINAL: normandouellette

Re CG.

Hello Tim (Krproton)

I have just figured out the CG problem I had earlier. Mabe pass the word around since I'm not the only one changing the "foam" wheels. I have installed 4 inch Sullivan wheels. They are much heavier and the same in the front 2.75. Now from 5 inch cg with gears down, my cg moved aft 1.25 inch! waqy more then 1/2 inch. So inconciously when you said setting up the CG @ 5.5 inch with gears up is the way to go with a different wheel set-up. To convince myself, I switched to the 3.87 inch foam wheels and the 2.87 noze wheel. the cg moves aft by less then 1/2 inch when gears up.

For now at least I'm convinced that the cg should not go too far behind when actuating the gears..

Do you think it is advisable to check the CG @ 5.5 inch when using the Robart retracts and a different/heavier set of wheels? When I add brakes on this the CG will again move back....that should not be?

Thank you for your attention


Normand, there is no C.G. problem.

In my explanation yesterday, I used the word "hypothetical" when mentioning the distance of 1/2". Please go back and re read what I wrote. What I said was, if you insist on checking the C.G. with the gear retracted, you have to find out the distance between the C.G. when the gear is down and the C.G. when the gear is up. Whatever that distance is (my HYPOTHETICAL distance was 1/2" to use as an example), you have to add that to the 5" in the manual if you want to check the C.G. with the gear up.

Here is a mathematical example:

X = C.G. with gear down
Y = C.G. with the gear up

Y - X = difference between C.G. with gear up and C.G. with gear down (Z)

If you want to balance the model with the gear up, balance it at 5" (the C.G. specified in the manual) + Z

Again, we accounted for heavier wheels and retracts when testing our models and finding the optimum C.G. which is recommended in the instruction manual. The model also has a C.G. range of 1" (1/2" behind and ahead of the recommended 5" ).

I hope this helps you out! :)




timothy thompson 11-09-2007 09:24 AM

RE: Top Flite B-25 ARF (Tecnical, tips, suggestions)
 
hey krproton how can scalenut52 offer the b-25 FOR 599.00 I FEEL TAKEN . its a rotating ad on here. hes sold several for that price

pettit 11-09-2007 09:28 AM

RE: Top Flite B-25 ARF (Tecnical, tips, suggestions)
 
He sells them at a loss and makes up for it with volume.

timothy thompson 11-09-2007 09:30 AM

RE: Top Flite B-25 ARF (Tecnical, tips, suggestions)
 
well i dont think its fair. i paid 680.00 im showing this to my LHS. They should do the same thing for me

pettit 11-09-2007 09:35 AM

RE: Top Flite B-25 ARF (Tecnical, tips, suggestions)
 
Everybody knows that hobby dealers pay a bit less for a product from a manufacturer than you can buy one for.

The difference is called profit.

It puts food on his table, keeps the lights on and the water running.

Maybe your hobby dealer wants just a little more profit than the other guy.

jbarnes 11-09-2007 09:39 AM

RE: Top Flite B-25 ARF (Tecnical, tips, suggestions)
 
$574 at our LHS, owner said they gave the hobby shops a deal on the initial order. Of course this is the same guy that sells the new 9303 for $525.

timothy thompson 11-09-2007 11:42 AM

RE: Top Flite B-25 ARF (Tecnical, tips, suggestions)
 
i stand corrected it was a 120 dollar difference! doesnt seem right ill see what the LHS will do for me

flaviosi 11-09-2007 03:19 PM

RE: Top Flite B-25 ARF (Tecnical, tips, suggestions)
 
1 Attachment(s)
Hi, guys,

For those of you complaining about the shipping costs, look at how much I'm paying for mine, on the pic below... [:@]

Greetings,

Flavio

sgoen 11-09-2007 03:24 PM

RE: Top Flite B-25 ARF (Tecnical, tips, suggestions)
 
O my god, 400.00 for shipping. How big is the box?

flaviosi 11-09-2007 03:32 PM

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

O my god, 400.00 for shipping. How big is the box?
Relax!!!

I'm outside US...

Flavio

krproton 11-09-2007 03:35 PM

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


ORIGINAL: flaviosi

Hi, guys,

For those of you complaining about the shipping costs, look at how my I'm paying for mine, on the pic below... [:@]

Greetings,

Flavio
But hey, you saved $8.99 with the Tower Hobbies Super Saver Club! [sm=bananahead.gif]

flaviosi 11-09-2007 03:48 PM

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


But hey, you saved $8.99 with the Tower Hobbies Super Saver Club!
ahhh!!! You noticed that!!! Great deal, huh?? :)

And there will be more when it gets here. It will be here in about 5/6 days and Customs will apply Import taxes PLUS local taxes and the bill will be something like 500 bucks.

So, me, the poor 3rd world boy will pay 1,600.00 bucks for a plane you pay in US an average 650.00.

But I'm not complaining. It's just the way it is.

Flavio

norm 11-09-2007 04:47 PM

RE: Top Flite B-25 ARF (Tecnical, tips, suggestions)
 
Way to go Flavio...when you think of it after all it is only money! Whats a couple hundred box in the life of a man? keep your good spirits guys try & remember you often paid a lot more for a lot worst! Be honest! This B-25 is worth what you are willing to pay for it not how much the other one paid. Concentrate on your build.

krproton 11-09-2007 04:48 PM

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

aren't there hobby shops in Brazil that carry Great Planes products? Could you get your B-25 from a hobby shop? And if so, would the taxes and delivery charged to a dealer be less than you would pay?

I feel terrible that you have to pay all those fees!

camdyson 11-09-2007 08:24 PM

RE: Top Flite B-25 ARF (Tecnical, tips, suggestions)
 
How about $1100 AU when our dollar is currently $0.93 USD, and we're on China's doorstep! Still, a friend's boat can go through $1100 of fuel in a couple of hours, so it's all relative![8D]

Has anyone tried painting/weathering Matt Monokote - I'd like to do some exhaust stains etc? Thought I might have a go at giving it a bit of "character" without sinking too much time into it. A silver marker for panel lines/chips was another thought, probably all sealed with Matt polyurethane (which helps seal the film edges too). Main concern is the covering needing re-shrinking later, with paint/varnish on it.

Looking forward to some flight reports.

Cam

flaviosi 11-09-2007 08:40 PM

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


Way to go Flavio...when you think of it after all it is only money!
That's right! And the coffins don't have drawers or safes yet... Life goes in a glimpse. We have to enjoy it the best way we can.



Flavio


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