mark IX

My Feedback: (9)

Hi, I'm new to the electric scale world, so I need some information. I am interested in converting my BT 1/5 scale Spitfire to electric power. It's got an 83" ws and weighs around 15 - 18 lbs. Frankly, I'm not sure a kit this large can be converted to electric power. Anyway, I know I would need a motor, battery, speed controller, and possibly a gear drive, but where can I find some info / websites to determine what I need? What type motor would I need, the MaH rating for the battery, who makes the best speed controller, etc. I'm interested in turning a near scale prop, around 20-22" diameter, possibly a 4-blade.

Right now I can fly approx. 15 min on a 32 oz tank of fuel, is that acheivable with electric power? Any help would be greatly appreciated.

Thanx, Mark

normgoyer

No problem all you will need is money, lots of it. Both Hacker and Hobby Lobby and even Great Planes have good motors for your bird. Hobby Lobby has everything you need, their 53 series will work perfectly in your size plane. I suggest second mortgage or sell your extra Hummer or stop paying your mortgage, see no problem. Norm

mark IX

My Feedback: (9)

Thanx, for the response Norm. I went to the websites you mentioned and looked around. $$$$$$$$$$$$$$$ you're right....cubic dollars. Looks like $600-800 for this conversion depending on motor and battery size including the charger as well. I guess glow power is not that bad after all!! What really appeals to me though, is that these electric motors put out enough torque to turn a scale dia prop, perhaps even a multi-blade one. Also no cooling issues which means no large cut-outs in the cowl. That's what attracts me to this idea.

Ya know, come to think of it, .......... I only have about 1 year left on the mortgage............Hmmmmmmmm!!!

Mark

normgoyer

Hi Mark, I was born and raised in Northampton MA and didn't bail out for CA until I was 48 years old. Know your area well. Multi engine models will last a lot longer with electrics, try to find a way. Norm

thunder21

My Feedback: (2)

Here's a good motor/ESC combo for a 15-18 LB warbird:

KD 63-20L Brushless Outrunner 235Kv (AXI 5330/F3A equivalent)
https://www.unitedhobbies.com/UNITED...idProduct=2129

B2A-P80AHV H-Wing Pentium 80A 2-12S High Voltage BESC
https://www.unitedhobbies.com/UNITED...idProduct=3830

On a 10S lipo pack the motor will turn a 22x12 prop at around 6500 RPM.

The pack you'd need would be two 5s 4000 to 5000 mAH lipo. Those would run you $200-$300 each. A decent charger capable of charging those packs would be around $120.

systemspecialist

Hi Mark 1X

I am putting the finishing touches to a Topgun Spit. At 72" it weighs in at 12 1?2 pounds with C of G right on the money AND NO LEAD !

I have a Tornado 'Thumper' motor supplied by Overlander batteries together with 2 X 5 cell 4500 ma batteries and a Jeti Advance esc. I am turning a 16 X 10 prop.

I used to build giant scale Spitfires 15 years ago. Had to quit for various domestic & business reasons. I have been helping my 87 year old dad into electric flight and naturally got the bug again.

Electric is so coooool and as you point out electric motors fit beautifully in a Spitfire cowling.

Dont let these guys tell you its expensive.

1) Motor - £75.00
2) Batteries £ 200.00
3) Esc £100.00

With batteries you gotta think 'I am buying a year or two' s fuel in advance. If you do some really deep Googling you can pick up batteries from companies in China for peanuts. The Chinese will take anybodys money

I got 5000ma 11.1 v Lipo's with 20c rating fitted with the balance plug I wanted, at £25.00 EACH.

Now tell me THATS expensive. So stop looking in the 'Toyshops' and go outside the US and really start looking around you.

Also dont forget Ebay but be careful what you buy, of course.

If anybody wants a build thread on the Topgun Spit make your views known on this forum

t3adams

Hello, Mark.

For an in-depth discussion/build of a BT Spit, RcScaleBuilder (http://www.rcscalebuilder.com/forum/...065&PN=1&TPN=9) has some excellent information.

For example, this gentleman, John Ranson, says this for his Spit:
"The fuselage is about to be started and I have now decided that the AXI 5345/18 outrunner motor is the one to go for. Stian came to the same conclusion, but until it is tested then we cannot be absolutely sure. The fall back will be to adjust the prop diameter or pitch, or the Lipo cell count, but the plan is to use a two blade 20" x 13" APCe prop and 12S - 5AhLipos. It should be good for 2.5KW or about 3,3HP ."

I would go with what he says; he has been flying large electrics for years (check out his build of a 100" deHavilland Hornet as well), and has always had good results with his motor choices.

Good luck!

Terence

algutkin

My Feedback: (1)

First, We are not really inventing the wheel with this plane. There have been many many similar conversions. All you have to do is read the threads.

Second, this is the wrong site, try the other RC site for information, it is much more active. RCGROUPS

Third, who make the BT Spitfire? I only have completed three different ones myself and never heard of BT. If you are serious and want good up front answers, you need to post the stats of the plane like the stuff printed on the box ie. expected weight, wingspan, wing area etc. Then download and buy Motocalc software, it will give you some basics without buying components. After getting into the ballpark, you really have to exercise some knowledge and figure out where to buy the parts, or China made substitutes.

Fourth, you should not jump into electiic with plane this size as your first. There is too much to learn and you will have invested way too money for the lessons to be learned.

Fifth, When you get into larger planes, nitro or gas is really a viable choice for cheap power. This is weird coming from me, because all I fly is large electric. There is a reason, I hate the oil residu and smell of nitro, but I can't honestly say that electric is at the point of exceeding the performance of nitro or gas with large airplanes.

Sixth, I am from Connecticut and I would never believe a guy from Mass, except Norm, he walks on water. He said to mortgage the house, and he is right on point.

Think hard about your conversion, you might start with a smaller project and learn what is really needed. The motor, ESC and battery combination is just the small part. You need soldering skills, supplies, engineering skills, and a knowledge how the components go together. I'm only two years into this and I have spent thousands learning.

By the way the scalebuilders site is members only. the heck with that. Time is money, who wants to fuss and jump through hoops just to view someone else's project. Chances are the stuff is outdated, electric stuff changes daily, improvements are happening all the time, it's hard to keep up with modern technology. LOL

Al

normgoyer

Hi guys, I tried walking on water this morning but I slipped on the ice. What ever Al says about electrics is gospel. I too build giant electrics and I would hate to add up the money I have invested. But, I am enjoying the hobby more than ever. Norm from Mass who got smart and moved to SoCal

sean sweeney

My Feedback: (8)

Just my $.02 worth...

1. LiPo's are not cheap, but niether is glow fuel, and, Lipo's are coming down in price while glow fuel is gowing up.
2. Your aircraft, and all of its systems will last much longer with out the vibration of a glow motor.
3. Your aircraft will look just as nice after 100 flights, as it does on the first flight
4. No clean up after flying
5. Your car/house/shop/hands/clothes will no longer smell like glow fuel after a days flying
6. You can add a sound module/speakers and have it sound like the real thing
7. Your batteries can be used in many other planes
8. Brushless motors do not wear out, never need to be broken in, never need to be tuned up, adjusted, fiddled with, dont flood out, need after run oil, or glow plugs replaced,
9. No mufflers, and/or cyl heads sticking out of that beautiful cowl
10. Turn big scale, efficient props
11. Dont annoy the neighbors that built homes near your favorite flying field

Sean

normgoyer

That about sums up the reasons I changed over a year ago, never had more fun flyhing. Norm

roscoe13

The "BT Spitfire" refered to is a Brian Taylor plan. Bob Holman distibutes his plans in North America, but if you are interested, Brian is retiring from the business, so act soon.