BBA/Winter Build 2017/18 - Top Flite Corsair

willsonman

Builder Extraordinare
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Ok, time for the cat to come out! This winter I am going to be building the Top Flite F4U Corsair 0.60 size Gold Edition kit with all the details. This is a 1/8 scale model complete with the Top Flite radial and cockpit kits... but they may not be good enough. I have a lot of 3D printing to do to gussy this one up. I've got the full Robart pneumatic setup. TF recommends 90-degree retracts... all the scale guys know they are really 100-degree AND that gives you more forward rake for better landings. I've got the Robart oleos and installed a brand new set of trunion collets in them so they seat perfectly onto the retracts.

I purchased this kit from a club member for all of.... $20. I've picked up the other parts over the years knowing I would eventually build it. This particular kit is what got me OUT of the hobby years ago and I am coming back now as a more seasoned builder and pilot. There are parts that have been assembled but they will need a good inspection and some repairs.

Also of note is that Carl (wilmracer) Lydick will be joining in when he can. The guy lives an hour away and frankly we are BOTH getting a bit worn out from these big builds. So as he wraps up his current list he will be jumping in here when he can.

Lastly, the great guys over at Grayson Hobby will be sponsoring the power setup for this one. Its a HUGE contribution to another great project and I look forward to good parts from better guys.

I will of course be updating here and using this thread as a worklog and discuss issues and solutions but I will probably be posting some things in video format as well. Changing things up a little with that.Feel free to tell me what's crap and what's not.
 

CrashRecovery

I'm a care bear...Really?
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Josh just let me know if you need a hand.... I'm just a little further down the road then Carl.
 

nhk750

Aviation Enthusiast
Nice! I love this plane and the kit really does it justice. This will be a great build thread.
 

willsonman

Builder Extraordinare
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Thanks for the support, guys!

jsknockoff: This will be electric. I've done several other birds at this size and I'm pretty familiar with how they perform and what electronics to use. I'll go over that in some detail when I get to that point.
 

nhk750

Aviation Enthusiast
Electric? YES!!!!! I am super excited now! I love electric conversions!!!!

I think the technology these days makes for a more scale looking model when going electric and they also sound cool too.
 

willsonman

Builder Extraordinare
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Oh, you just wait until you see the scale radial in store for this one.

I have a Top Flite AT-6 Texan as well as a giant P6-E Hawk. Then my Jug and Pitts S2-C... all electric conversions. Technically my Sikorsky could be considered one as it was intended to be glow but I scratch built the crap out of that one. Any airplane with a 76" span that comes in at 4 pounds just needs to be electric. ;)
 

nhk750

Aviation Enthusiast
These days you can electrify any aircraft, even full scale. It is so much simpler, cleaner, reliable power, and even more power than IC in most cases.
 

jsknockoff

Active member
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Thanks for the support, guys!

jsknockoff: This will be electric. I've done several other birds at this size and I'm pretty familiar with how they perform and what electronics to use. I'll go over that in some detail when I get to that point.

I’ve been wanting to build something that size in electric but I don’t have the knowledge yet to select a proper power system, it would be just educated guessing. I’ll be keeping an eye on your build, maybe I’ll jump in on a Gold Edition fighter around Christmas.
 

Joker 53150

Mmmmmmm, balsa.
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These days you can electrify any aircraft, even full scale. It is so much simpler, cleaner, reliable power, and even more power than IC in most cases.

Yes, but... going electric on bigger planes gets expensive, fast. $100 for an ESC, $100 for a motor, $100 per battery for 7 minutes of flight (rough numbers, could be lower or much higher). That’s why I love gas for big planes, I can fly for hours on a gallon of gas, they sound great, etc. but it isn’t for everybody and they aren’t as quick and easy as electric.
 

willsonman

Builder Extraordinare
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Then there are dead sticks and other safety issues. ;) For some help in the conversion process I'll leave some links to my other ones posted here:

P6-E Hawk
P-47 razorback
AT-6 Texan

My general philosophy has been to get to at least 100W/pound while trying to keep the RPMs minimal (~7-8K). The Hawk is a great example of this. The point is to try an minimize the amount of high RPM so that you hear the air, and not the prop. Its more of a wooshing sound rather than closer to that of a pusher prop. Carl's video of the Hawk at FF2016 is a good recording to show this:

That said, just by changing to a different prop style you can get different sounds as well. For a more hot rod sound take this example:

Now, the sound is a result of energy loss being transferred to air cavitation rather than speed but clearly it is a well-powered aircraft anyway. Some older Falcon props were well-known in the 3D world to "rip" the air like this and became quite obnoxious and most clubs banned them for the amount of noise they made.

While the bigger electric setups do get more expensive in a hurry, IMO they are more reliable, cleaner, quieter (I like this), and generally pull the aircraft around in a more scale manner. I do not fly my scale aircraft in any other way than scale. Coordinating my turns and doing basic maneuvers. The Sikorsky makes this look so very easy. While it may not be as "exciting to watch" it is quite a challenge to do... which is why it is part of judging in a scale masters competition. It is just a different flying style like 3D, IMAC, quad freestyle, or anything else.

 

Joker 53150

Mmmmmmm, balsa.
Mentor
I've heard of guys making the Stuka dive bombers, and adding some kind of whistle to it to re-create the proper sound during a dive. I think it was the oil coolers in the wings on the Corsair that caused the sound, wasn't it?
 

nhk750

Aviation Enthusiast
Yes, but... going electric on bigger planes gets expensive, fast. $100 for an ESC, $100 for a motor, $100 per battery for 7 minutes of flight (rough numbers, could be lower or much higher). That’s why I love gas for big planes, I can fly for hours on a gallon of gas, they sound great, etc. but it isn’t for everybody and they aren’t as quick and easy as electric.

Ah yes the old gas or electric argument. Well, you don't have to keep buying gas and it's a whole lot cleaner, plus my nerves are shot after 7-10 minutes of flight anyway as I fly mainly aerobatics and push myself and the aircraft. That being said, I sure do like some of the multi cylinder gas engines out there. They look so pretty, but cost so much...someday...

Your right about the high price on larger electrics as I'm into my Hog around $300 for the power so far. But gas gets up there too.
 

Joker 53150

Mmmmmmm, balsa.
Mentor
Ah yes the old gas or electric argument. Well, you don't have to keep buying gas and it's a whole lot cleaner, plus my nerves are shot after 7-10 minutes of flight anyway as I fly mainly aerobatics and push myself and the aircraft. That being said, I sure do like some of the multi cylinder gas engines out there. They look so pretty, but cost so much...someday...

Your right about the high price on larger electrics as I'm into my Hog around $300 for the power so far. But gas gets up there too.

Some arguments are fun to dig up and kick around occasionally. :) I'll never argue against the convenience of electric, and I've got a few dozen planes that run batteries. I'll also agree that you do have to keep buying gas, but a single gallon can last for multiple days at the field and even with oil is under $3.00. You still need to charge batteries, but a receiver pack is usually MUCH smaller than a big flight battery, and far cheaper.

Some of those radials on the market sound incredible, but they usually cost more than my car! The actual construction is still in the planning phase, but I currently own a P-38 kit with a 100" wingspan, which obviously requires two engines. It calls for roughly 1.25 size in glow, which should let me overpower it slightly with dual 26cc gassers. Electric was an option until I priced it out. Motors and ESCs combined would cost around $500 and batteries are also stupid-expensive. I can get 26cc gas engines for around $200/ea and fly much longer and with better sound. Yes, there is some tuning involved and it's a little messy, but overall it really isn't nearly as bad as the glow engines. My gas Cub's 23cc is a little messy, but it runs rich. The gas Citabria's 26cc is very clean by comparison, and usually doesn't need any real cleaning at the end of the day. I'm also just getting into glow for some stupid reason, and have found it to be a horrendous mess by comparison. But it's still fun and something different to learn.

Just my take on it, but electric is great for up to around .60 size, gas really covers the sizes above .60 well, and glow is a dying product.

Sorry for the hijack of the thread, Joshua!
 

agentkbl

Illegal Squid Fighting?
I'm a huge fan of the modern 2 stroke weedeater engines (~21cc). super reliable, lightweight (once you get 'em out of their heavy duty clutch guards) and I can get about an hour of run time on about a pint of gas. (I don't fly them, but I have other experience with them.)

echo makes one that's nearly flawless, other than having to remove a little nylon plug to get at the fuel mixture screws on the carb.
 

willsonman

Builder Extraordinare
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As for the whistle... I dunno. I need to dig into it a bit more but one of the modifications to the oil cooler vents is to make something that looks better on my 3D printer. Perhaps a whistle could be incorporated into the print somehow.

As for the gas vs. electric debate... I fly electric and I like it. Jeff likes a bit of both and that is cool too. I really don't care what you fly as long as you fly. There are builders in this world who makes these incredible machines only to have them sit around and never fly. ahem... Bugatti... ahem. :p