krproton

Hi again "ifly."
When I get back to work after the first of the year I promise to contact the product manager and plead with him to do a one-time run of ARCs. I don't have much more influence than you, the customer, because it all comes down to what they think the demand will be. But hey, I'll try!

I think high-end warbirds like these warrant ARC versions because "high-end" modelers such as your self prefer their own finish and variety.

We'll see...

skubacb

krproton -Mike,

You missed this so I am posting it again: I have a pair of almost new Saito 72s. My aircraft will have the Robart retracts and will have no additions to the stock plane.

Since the prototype flew on the OS 70s, would I get about the same performance with the Saito 72s or do I need something more?
_____________________________

Cheers,
Craig

krproton

Hi Craig!
Sorry I missed your previous post.

I don't know anything about those Satos, except for their reputation, which I think is pretty darn good! If I'm correct, those Saitos will fly your B-25 wonderfully--just as do the O.S. .70s. Read up on my earlier posts in this thread. I also posted in another, much earlier B-25 thread started by someone else, about how my B-25 flies with the O.S. .70s. I don't see why it would fly any differently with your Saitos. I would suggest starting with 2-blade props though. I think they will provide a tad more thrust. When you get complete confidence in your engines and know how the plane handles, you could sacrifice a bit of flight performance for a much better appearance on the ground, when the engines are not running, with 3-blade propellers.

I didn't break in my O.S.'s on a stand--just ran a few tanks on the plane with the cowls off so I could easily make all adjustments. Then another tank with the cowls on. After you have complete confidence in the engines and get them tuned the way you like, you should be good-to-go. Some will probably recommend breaking in on a stand. Can't argue against that either.

Keep us updated!

Tim

norm

Hello Skubacb

Here is some information that can help you. (tech data published)

OS 70 surpass 1.1 hp best prop 13 x 7 apc 2 blade. 12 x 6 to 8 pitch MAS for 8500rpm
Saito FA72 1.4 hp, best prop 13 x 7 apc 2 blade. 12 x 6 to 8 pitch MAS for 9000rpm
Saito FA82 1.6 HP best prop 13 x8 apc 2 blade. 12 x 8 pitch MAS for 9500rpm

I ly this plane with Saito 82's and it is very well powered, not overpowered but knocking at the overpower door. The saito 72 is most certainly a good choice, if you have them. My Opinion with Saito is why don't you get the most power out of a mold? In the small cylinder engine you have the 72 and 82 are the exact same dimensions, why not get the best out of it? Same with the 91, 100 and 125. Why would you settle for 1.6 hp with the 91 while you can get 2.2hp from the 125 for the same size. Again with the 56 and 62, get the 62!

The 72's will power this plane perfectly. I would fly it with a pair of 12 x 8 APC props 2 blades and later do like Krproton says when you are familiar with the plane you go with 12 x 6 MAS 3 blade for no more then 10000 rpm or 12 x 8 MAS 3 blades if you exceed 10000 rpm with 12 x 6 MAS 3e blades.

You will likely exceed the performance from an OS 70 surpass.

This plane is great for engine choices and if i rebuild it , I'm going with the OS 70 Surpass with pump / Saito Fa100T (twin cylinter flat0

MLDELARUELLE

All,

Perhaps my last post was missed.
So nobody else have issue with the retracts. The 3/16 wire is strong enough ? The broken one I saw in this thread is the only one ?

Is it possible on the Robart retracts to drill a bigger hole if necessary ?

Thanks.
Best regards
ML

timothy thompson

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norman outrunners are what you want!!!!!!!!!!!!!!!!

camdyson

ML - I suspect few on this thread have got to the flying stage yet - "Kryptonite" Tim and Norm seem to be the only ones, so given Norm's experience I'd be wary. Noselegs tend to get a hammering - especially on grass strips - so if there's a way to go thicker I would do it.

If you fly off a smooth surface, the specified Robarts are probably o.k. - I've got a set so time will tell....

As an aside, regarding gyros, the JR G500A Norm used isn't available in Australia, and the nearest equivalent is $$$$$. I discovered the G500A's are all being discounted in the U.S. now for $149USD - a relative bargain - so have ordered one. Suspect they're being phased out by JR, but who cares if they work.

Re pilots, I ordered the last 2 Vailly 1/9 USAAF WWII pilots (torsos) in existence, and they were lost in the mail![:@] Anyone found other good USAAF WWII pilot torsos in this scale?

Just waiting on a few accessories to turn up, then will be clearing the bench and getting stuck in.

Merry Christmas all,

Cam

norm

Bonjour ML,

Je vien de lire votre demade d'information sur la tige de 3/16 qui ne serait pas asser solide. Je vous suggere pas de faire de modifications.


English version!!! HA HA well I'm French Canadian...

Hello ML,

I just read your info request on the 3/16 pin on the steering noze gear. It is not hard to assume that it is not strong enough and is not made for rough runway. Robart markets their 3/8 size struts for 4-10 pounds airplanes, visit the site: http://www.robart.com/RoboStruts/380_Series.aspx ,

After visiting their site you must understand that the noze retract is made for lighter aircraft. The problems I had with the noze gear was due to a landing on a frozen runway. A few wet days preceded this incident and with -7C (20F) on that day the runway edges were bumpy and rough by the risen frozen ground. Another factor was the crosswind (90 degree) landing added roll speed to this landing on a bumpy runway...it borke. My opinion is that it it were any stronger the fuselage frame would break instead.

The only opinion I may say is to make certain to land on smooth grass runway or paved. The better landing technique is to keep weight off the noze as much as possible after touch down. Paved runway unless at least 500 feet would require brakes on that plane, because it will roll off.

Finally the 3/16 axle pin on the noze gear is definitly not strong enough to withstand the beating of a rough landing or a rough runway but I' rather repair small damages like I had instead of replacing the aircraft. No I would not modify trhe noze gear. I know now not to commit to a less then perfect landing if I have the choice.

fytrjok

My Feedback: (2)

Cam,
I suspect you're right that since this plane is so new, few have seen the wild blue. I have had mine for about a month now and it's nearly finished. I did spent a lot of time weathering and detailing but I'm almost ready to pick a name and clearcoat. Then, it's just a matter of waiting for the snow to melt off the runways! I guess this will give me some time to hopefully locate some 1:9 scale crew. A friend of mine received some Century Jet pilots but returned them as they were pockmarked and not up to standard. I too ordered pilots from Vailly and was told the 1:9 pilots are no longer available. What are we going to do? I did see that Hanger 9 has WWII busts in 1:9...but I think we need the full body. I really don't want to have to fabricate the lower half. I also don't want to pay a fortune, so I guess we'll see what turns up. By the way, anybody know where I can find more examples of B25's that were in the same group/squadron as "Executive Sweet"? I'd like to do one with different nose art. Here's a few pics as this great bird nears completion. Just one more question to Krproton...I'm at 5280ft. and am used to using the top end of recommended power plant size for obvious reasons. I've fitted a couple of the older (tried and true) OS 70's to the plane. What'dya think...will I be OK? I'm at about 20-21lbs.

Doug

camdyson

Now THAT'S what I like to see - great work fytrjok. I'm hoping for a similar finish on mine. Did you airbrush the panel lines? How did you prep the covering for paint? There's some stuff available over here they use to prep car plastic bumpers for paint - sounds promising.

Again, great work. Can't wait to get stuck in now. Will let you know if I have any luck in my pilot hunting!

Cam

Edit: just saw your comments on the AFR-bash thread - answers my questions!

timothy thompson

My Feedback: (1)

nice job you now can detail that bomb bay ! im putting rivets on usinf a product from flite metal and they look great i too will airb rush and matt coat. since im electric no fuel proffing issues. ive got close to 40 lbs of thrust using 4s 2p and my final setup will ne 6s2P. this is a great scale platform that you could take to scale contests even tough those guys say no way. i did the same servo setup only mine is on the other side of the bulkhead. You know there were scale covers over the hydraulics? look at my pics.

MLDELARUELLE

Salut normandouellette,

Merci pour la version française/anglaise ;-)
The build TopFlite kits trains my english !

More seriously, thanks for your answer. Does krproton have an advice on that . Did the TopFlite team tried various landing gear ? What were the results ?
My runway is rough and very often, the crosswind are 90° too.

And, is the main gear strong enough ? 3/16 too ?

There is no spring on the robart retratcts. It would less scale, but perhaps more efficient.
And, did you add lead ? Where ? Perhaps one could make the nose stronger if the lead is in.

Best regards
ML

iflyf4u1a

My Feedback: (1)

For the guys that have done the bomb bay (which look really sweet) - what are the inside dimensions (LxWxD) of your bomb bays? How much room you do you have in there for bombs?

timothy thompson

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ill let you know when i turnover the plane. i made frag bombs and 100lb and 500lb. i cant find anyoune whoi makes exact scale replicas so i did the best i could do. im not dropping them as ill never find od bombs in green grass. if you need pics pm me ill give you anything you want I have a cd with 500 close ups.

diverdon

Looks like everyone is doing a great job.

I got my bomb bay done. Thanks for the info Tim.

I'd like to take a moment since I'm new to this forum to say thanks for all the info and wish....

Everyone A Merry Christmas & Happy New Year!

iflyf4u1a

My Feedback: (1)

krproton - Thanks for the assistance. Hopefully they'll do a run of ARC's

skubacb

normandouellette: Thanks for the info. Interesting that you would go back to the OS70s. I was thinking about that myself. Since Tim is telling us and everyone else, that the 70s are good enough, then reliability comes in. Saitos are dead reliable. Do we really NEED the pump on the new OS70s. The tank positions seem to be correct for not needing a pump.

I would like Top Flite to include or have available on their website engine templates for other recommended engines. They should at least have the templates for the engines they feel are appropriate for the aircraft. I would like to see templates for the YS63 and Saito 72/82. Why not also state what the maximum recommended engine weight is.

So often we all have to go into the forums when the company could have just listed those things we always have to ask here.

norm

Craig,

There is a good difference between the OS 70 "Ultimate" and the OS70 "Surpass" in terms of performance, size, HP, and weight. For top Flite to include a Saito Templates, the one who would do this would get fired. Top Flite is together with great Plane, Hobbico tower Hobbies... And fierce competitors with Horizon and Saito.

There is also some Mod's to install a saito 72/82 with the position of the engine mount. You have to make some special fittings to install the Saitos and a separate fuel pump if you whant to go straight pipe. the B-25 firewalls are very small 2.5 x 2.5 inch

The OS70 Ultimate has a built in pump and smaller then the Surpass 70. The Ultimate series is also stronger. The size of it fits in the cowl. There is also the new OS81, same size as the surpass 70 and equivalent in performance and heavier to the Saito 82...but no pump.

You really need a pump if you intend to run your engines "Straight Pipe" without a muffler to creater fuel pressure in the tank, for fuel feed.

Now that I have the 82's installed nothing would make me take them off.

Normand.

Bosco2

My Feedback: (42)

Hi Tim,

I will say that all the information that I have been reading in reference to the B25 has been a wealth of information, Im interested in purchaseing the TF B 25 at the end of January along with the retract geare and Im fortunate to have two Saito 80 4s in stock,

One question that I would like for you to ask one of your coworkers or if you all ready know the answer is that would it be pratical for the right side engine to turn Clock wise Saito make's reverseing cam for the 56 Thru 180 and they are not to expensive I know cause I have one for my 80 and one for my 50 as well as for my 180,
The next's question would there be a problem with the engine installed inverted will the fuel tank and the carb be at the same hight, I do not like a siphoning problem. Let me know when you have the chance.

Many Thanks and, Happy Holidays to All.

Bosco2

My Feedback: (42)

Bomb bay doors would be outstanding to this kit,

fytrjok

My Feedback: (2)

Bomb bay internal dimensions are roughly 14" long by 6" wide by 4" deep. Cutting in the bomb bay is relatively simple but takes time. I do wish the designers would have located the nose wheel servo mount a few inches forward of it's stock location. It does need to be moved if you want to do a functional bomb bay in the scale location. One of the things I liked about the Wing Mfg. kit was the whole section of the fuselage under the wing was removable. It was much easier to modify it to include a bomb bay. I suspect that some enterprising designer will mold bay doors, nose and top canopies etc. and offer them for sale. That'll be great but I ain't waitin' 'till next summer for the upgrades...and besides, doing it yourself helps keep the building skills from withering away completely![sm=50_50.gif] By the way, the little bombs that came with the Eflite P47 are just about the right size. I prefer dropping a load of candy...for the children ya unnerstan'!

Hellcat716

My Feedback: (2)

The YS 63 uses the same template as the OS 70.

timothy thompson

My Feedback: (1)

i have the eflite p-47 where is my brain thanks heres some pics

sgoen

My Feedback: (5)

Does anyone have the enginesync on their B-25? If so, hoe did you attach the sensor to the engine?

norm

Sgoen,

Twinsynch installs with a spinner backplate only. You will not be able to install twinsynch to your B-25 with propnuts. Sgoen, do not "bust your chops" with a twin synch. A glow driver is what you whant. I suggest to install 2 MCD466 (if you use 2 channels for your throttle..less heavy option), one for each engine or a MCD472TE (if you are using only one channel for your throttle..heavier because you need an external battery) from sonic tronics http://sonictronics.com/xcart/customer/home.php . Call Hank over there and ask hip how to set up and he will suggest you the best.

As for a twin, if you have an idle speed of +/- 300 rpm or less and full throttle +/- 400 rpm or less you will be fine. you will never be able to tune 2 engines the same and if you were able to, you may lose the full power needed by one engine. Suppose that one operates at its optimum @ 9700rpm and the other is set at its optimum @ 9450. Lowering the first will drastically reduce the HP produced by that engine. Full HP is what you whant from both engines and you will notice that even if you were 600-700 rpm different it is not desired but hardly noticeable. Do your best to adjust mechanically the throttle of both your engines and fine tune them with the radio. If you are able to adjust the throttle curve adjustment you may also whant to adjust rpm @ at different throttle setting and there you will obtain optimum performance out of your engines. Hank @ sonic tronics may help you further and help you demistify the "need" of having both engines spin the same. you may also read some expert advices on this site: http://rcwarbirds.com/Techniques/Technigues.htm#t2 . You will find this site very helpful.

Hope this can help you.

BTW all of you Michigan, Indiana, New York, Illinois guys, if you plan to visit Montreal this coming summer, I'm hosting a Warbird Funfly at our club, it will be interesting June 21 & 22. (you are all welcome with your B-25)