BoilerFlyer

Gents,
I've seen a website that gives a chart for an equivalent electric motor for a gas motor -- given eng size, prop size, etc.
It was either a chart or a calculator.
Does anybody have the link or know what I"m talking about?

Thanks for any help,
Phil

FlyingMonkey

This is a good one...

http://www.csd.net/~cgadd/eflight/calcs_gloconvert.htm


There's this, it's free, you just have to register.

http://www.rcadvisor.com/calc


The common rule of thumb is to go with watts to pounds.



< 50 watts per pound. Unable to rise off ground
50 to 60 watts per pound. Can rise off ground and perform simple aerobatics
60-75 watts per pound. Easily loops from level flight. More impressive aerobatic performance.
75-100 watts per pound. "Fighter"-like performance. Aggressive climbs
100-150 watts per pound. Extended vertical runs. Unlimited aerobatics
150 watts per pound & up. Wings are unnecessary

Larry3215

I agree. I think its better to go by weight than try to convert a glow size to a motor size.

Keep in mind that those numbers are general guide lines and there are exceptions all along that list.

It would help if we knew what type of model your converting. War birds for example need very different power systems than 3D flyers or trainers and old timers are a different breed again.

Things just work differently with electrics.

Henry Sistrunk

Here is the one I use.
http://www.electrifly.com/powersyste...brushless.html

BoilerFlyer

Thanks Henry, that's what I'm looking for, something nice and simple.
Now I just need to convert that to the different manufacturer's model numbers for the elect motors. Will they ever get together and be uniform?

Phil

FlyingMonkey

The trouble you run into there though, is that none of the numbers for one brand of motor, match up with the sizes of other brands of motors.

So, if you want to pay the over inflated prices of one brand, just because they made a chart, then shop away.

With electrics, it pays to be an educated shopper.

Sure, it's confusing to try to figure out what watts you need, as well as which KV rating, but that's what we're here for, until you've learned it for yourself. (We, meaning they, I am still working on my learning curve as well )

BoilerFlyer

Flyingmonkey, Thanks, I know what you mean about the manufacturers using different model nbrs. I've been using E-Flite's outrunner motors which are competitively priced and run great for my purposes. I've only been able to find them at Hobby Town USA, nothing on-line yet.

Here's one I'll throw at you guys: my buddy is looking at converting a Great Planes Taylor Craft, it's actually called a T-Craft. Uses a .25 glow eng, 50" wingspan. I don't have any weight yet, it's still being covered.

Thanks!!!!

FlyingMonkey

You'll find some people that feel they are highly overpriced. There are plenty of "budget" motors out there that have similar performance, for half the price.

Darrell B.

Horrizon Hobby sells the e-flight motors on their website. Like was said in the above post, some people feel that they are over priced. Sometimes you just have to go with what you know and accept the cost. I have a friend that used only the motors that he buys from Hobby City. He is very happy with them and to my knowledge has never had an issue with one of them. They have some nice lipos also.

Darrell B

cv640

I have tried E-Flight, Himax and Scorpion outrunners and with my experience with them I will never buy another E-Flight motor again. It is not that they are bad, just that you can get a much better motor for less money. I would check out Scorpion Motors at innov8tivedesigns.com. Don't be afraid that they don't cost enough, these are the best motors I have ever used.

FlyingMonkey

are you just a loyal customer, or are you in some way affiliated with innov8tivedesigns.com?

cv640

Just a satisfied customer. After using E-flight motors I tried Himax outrunners and that was a huge jump. The Himax actually perform like the numbers say they will, unlike my experience with E-flight. I recently dropped a Scorpion 3020-12 in my GP Combat P-51 to replace my Himax 3522-990 (which used to have the most power of any outrunner at its weight) and the difference is huge. This thing was the fastest airplane at the field with the old motor and now it isn't even fair to the other guys. The Scorpion weighs less as well and will handle 800watts as opposed to 400watts for the Himax, not to mention it only costs $59.

FlyingMonkey

are there any other good scorpion retailers you could recommend?

everydayflyer

http://www.rcdude.com/servlet/the-Br...ies/Categories



he is a member here and has a bunch of users Scorpion powered models on his site.

I am another very happy Scorpion owner / user. I use to pay a lot more for AXI Gold motors but after finding Scorpions about 10 months ago that is all I purchase. Several of my aircraft in the this Thread.

http://www.wattflyer.com/forums/showthread.php?t=25042


My latestest Scorpion powered aircraft

http://www.wattflyer.com/forums/show...&postcount=201

Charles

EpoweredRc

I know I am not, Heck NO ONE lets me beta test anything or have anything for discount for flying, But Scorpions are the best motors for the buck, I will not buy another motor ever.

Ramovan is a member here www.rcdude.com hes a great guy and as EDF said has many satisfied customers airplanes on his site here
http://www.rcdude.com/servlet/.fc11d...ionSetups/Page

I have e-flite motor and can not complain it runs strong but I could have gotten a way better Scorpion to match is way less money.

I also like Himax but the same thing, higher price and I do not feel there as well made as scorpion.

FlyingMonkey

You know how it goes, we value the word of our fellow forum users.

Then you get someone in here, that's saying how great something is, but forgets to tell you that he works for that company (either the manufacturer, or the retailer).

We like having company people here too, I just would like to know if they are saying it because it's a great product, service, retailer, or because they have a financial interest in seeing it promoted.

EpoweredRc

Totally understand. Some might think I worked for A123 racing, Scorpion or Hitec as I promote there products but I do not get anything for it just a happen customer. Normally have all three stickers all over my planes. and have a Scorpion neck strap.

Dr Kiwi

One crude rule of thumb - may have come from Lucien Miller of Scorpion Motors - to convert glow to a comparable electric - multiply the cubic capacity by 2000 - answer in Watts. [0.25 x 2000 = 500] Thus your friend needs to look at ~500W (assuming the plane will weigh no more than 4-5lb).