Voyager2lcats

I've been known to get it right every once in a while! Don't let those things fall on you.

Bob

Lieutenant Loughead

Revisiting this -- my kids decided to get me a brushless motor for Father's Day...

What would be a good, inexpensive motor for my very own GWS P-40? I'm a big fan of Hobby City. I'm not a big fan of the TowerPro-type motors, which have bent motor shafts every other time you belly land...

From what I understand, the motor I used to build the airplane in this thread, was a good fit for this airplane... However, that motor (Eflite Park 480, 1020 Kv) is a $70 motor, and I don't want to hit my kids with a $70 Father's Day bill... :o

Does Hobby City make an Eflite Park 480 knock-off?

Grasshopper

How wheavy do you expect the P-40 to be Guy? My Ultrafly P-40 (the one I maidened with you and James) has a Park 450 in it with plenty of speed. You might be able to find a motor close to that. I'm also using an A22-20L in my P-47 and Hurricane that has more power than the 450.

Here's where I bought the A22-20L motors: http://64.33.154.92/blackdogrc/brush...es.jsp#A22-20L

Lieutenant Loughead

Thanks, Tom -- that price ($35) sure is right. What prop are you using with that motor?

I expect my P-40 will end up weighing just about the same as the one I built in this thread (26.5 ounces)... Mine might end up an ounce or two heavier, if I decide to fiberglass it...

Grasshopper

I'm running an E-Flite 10x8 with a 3S 2150 15C pack and a 30 amp ESC. Here are some readings I got trying other props with the 22-20L on the bench.


E-FLITE 10X8 25 amps 245 watts
APC 11X5.5E 22 amps 245 watts
APC 10X7E 23 amps 233 watts
GP 10x4.5 SF 22 amps 218 watts
GWS EP 1060 20 amps 215 watts
APC 10X5E 18 amps 187 watts
GWS 9X5 -3 HD 19.8 amps 221 watts

Fly Time

Hey Guy, I've got one of those motors too, only I got mine from a Hong Kong eBay seller for about $25 delivered. The model number is the same as the one that Black Dog sells, but it is 1050kv vs. 920kv through BD. Not sure why the same model number would have different ratings, but then again there are two versions of the EF 480 as well.

Anyway, I have it in my Hobby Lobby Gee Bee Mini Sr. Sportster, which weighs a little over 2 pounds all-up. It turns an APC 11x5.5, which pushes the motor a bit at 26 amps. That's a bench test figure, so I doubt the in-flight amp draw gets that high unless I'm hanging it on the prop. Great motor for the money. I'm really happy with the way it flies the Gee Bee.

Grasshopper

I also bought one of my A22-20s from Don's RC. He shipped it right out.

http://donsrc.com/cart/index.php?act...od&productId=6

Lieutenant Loughead

Thanks guys -- what kind of SPEED am I looking at for my 20-25 amp hicky?

thank you!

Grasshopper

I'm not sure. All I know is mine fly fast enough that they don't drop out of the sky.

If I remember right, you saw my P-47 fly when I was in Tulsa. It moves along pretty good and it weighs 40 ounces.

Lieutenant Loughead

Okay -- yes, I do remember that...


So, you were flying that E-Flite P-47 Thunderbolt, with:

• 22-20L brushless motor
• E-Flite 10x8 prop
• 3S 2150 15C pack
• 30 amp ESC

Is that correct?

I ask, because the GWS P-40 is very similar in size, weight, and wing area, to the EFlite P-47.

Grasshopper

That's correct but it's after it was converted to a bubble top, glassed and retracts. AUW is 40 ounces. I was flying the P-47 on a Park 450 originally before the conversion.

Fly Time

Here's a link to some video of my Gee Bee with a KA22-20L and an APC 11x5.5 prop. The battery is a 3S 2500mAh and the ESC is a 32 amp PowerUp. All up weight is around 35 ounces I think.

Lieutenant Loughead

Well, it's been a LONG time, but I finally ordered the motor for my P-40...

I went ahead and ordered the Rimfire 35-30-950 -- it looks like it's almost identical to the Park 480. I also bought some APC 9x7.5E, and APC 9x9E props (I didn't even know APC 9x9E props existed!).

I think I'm going to need a few extra batteries too! :o

Fly Time

9x9 is going to be really fast!

Lieutenant Loughead

That's how I like it!

My only concern is the amp draw... I won't know that until I test it on the thrust bench... :o

AETCBoom4

To those contemplating what motor to use in this plane. I would highly recommend the Rimfire 35-30-1250 KV and a 10x8 MAS "E" prop with a TPS 11.1 2100 battery. My original setup had the Eflite 480 1020KV.
If your wondering how I know, take a look at the build pics throughout this thread.
Hi, Guy, Long time since we chatted and the plane is still going strong, just remember to add a little right/down thrust when securing the motor. Don't ask how I found out.:o

Lieutenant Loughead

Hey there! It's great to hear from you! I've been wondering how the P-40 has been doing -- do you have any pictures, or video to share?

Why did you switch from the Eflite 480 1020kV to the Rimfire 35-30-1250kV motor?

Isn't the MAS prop a little "stiff" for belly landings? What about a MAS 9x7x3 prop (That's what I'm considering for mine...)

Alas, I still haven't started my build... My kids did buy me a motor for Father's day, and I elected to buy one (Rimfire 35-30-950kV) for the P-40 -- so there's no turning back now!

AETCBoom4

I switched to the Rimfire because I wanted more punch and didn't feel like flying at full throttle all the time. Half throttle with the 1250 is like full on the 1020. I'm not sure how it will be on the 950 but I definitely like it on the 1250.

The prop I'm using is the same one we started off with.
http://masterairscrew.com/10x8electr...propeller.aspx

I would imagine going with a 3 blade will decrease top end. I tried a 3 blade on my Turnigy PZ T-28. It was a 3x MAS 10x7E but decided to go with the same prop that the P-40 had and it worked perfect.

Definitely add some right and down thrust because the plane had some P factor rolling on launch. It was almost catastrophic on one launch. Also don't follow the cg in the manual it is off by at least 10mm. I can take a reading the next time I fly if you plan on copying what was done before. Remember the GP spinner that was used, the lighter weight of the rimfire was a perfect offset for the spinner's weight.

Sorry no video, but everyone that sees it fly is very impressed. I would avoid using the waterslide decals as they don't hold up.

I got in touch with Calliegraphics and she made some vinyl stick-ons that are an excellent quality. She probably still has the scan of the decals if you are interested.
http://www.callie-graphics.com/index.php

Lieutenant Loughead

That's great information -- thank you for sharing!

Hey -- how is the bottom of the airplane holding up? As I recall, you decided to only fiberglass the parts of the airplane which would touch the ground.

Are there any additional parts that you would fiberglass, to protect the foam?

AETCBoom4

reinforce the bottom and back 1/3rd of the fuselage to prevent skid rash in the flare. Also around the battery compartment, as over time the foam dings easily.

Alpea42

Ultrafly has come out with a nice looking foam P-40 . Saw it at L.H.S. this weekend it's $70. http://www.modelflight.com.au/ultraf...40_warhawk.htm

jismail

Hey folks, thought I would show you my latest mod...

After having numerous hard landings due to my inability to properly hit the small runway I have at the increased speed this plan tends to need to land correctly... I decided to add the flaps to this bird.

It was acutally very easy to do and only took about an hour from start to finish.

I used a single servo in the wing center with a 'Y" linkage to connect to a pair of "Z" shaped acuator rods and it went in pretty easy.

The rods are the type that have about an inch long portion of the rod that stabs into the foam of the flap and then runs down the edge, and I just made a small groove between the flap and the wing center compartment for the rod to sit in.

Wow, what a difference... The bird glided in at a much slower speed then previously required, and did not tipstall at the last instant as this bird was prone to before.

I would say that this mod was a success and as easy of a mod as it is, I would encourage others to do it if they are looking for this type of enhancement!

tommytorino

I love the flaps for the WOW factor, well done!

One day Ill drag my P-40 out of mothballs.

Tommy D

Kosh

Here's my version of the P-40 from a NPS Kit. Painted with Krylon H2O Gray and Yellow two lite coats did the covering and I left the bottom white. The plane is powered by a Himax 2816 - 1220kv outrunner spinning a APC 9x7.5 E prop, 30 Amp. Simple ESC with a Zippy Flightline 25C 2200 3 cell pack to make it all work.

I hate landing gear on most planes but the cowling looks too fragile to withstand many belly landings so gear was used this time. Because I fly off a grass field that means the plane will flip with every landing but its never caused any damage. Mine glides very well and all the landings are done dead stick with a very low touchdown speed. In the air the plane is very nimble with a good roll rate and snappy elevator, In fact the plane is very easy to put into a knife edge and hold it for multiple laps around the field. Not many warbirds do that well as this plane doesn't seem to mind when I throw some mild 3D stuff at it.

Well worth the $48 for it from a LHS, Well done GWS

odieyodie

I would like to add retracts to this bird using the new GWS retracts. Any advice or instructions would be really helpful as I have never done this before.