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Grasshopper
10-06-2010, 04:45 PM
I just bought a Great Planes 54" Shoestring and it calls for a Rimfire 42-60-800 outrunner. They pretty much go for around $80 everywhere. How is the quality of Rimfire and is there another motor comparable for less? I've looked at the Turnigys, Monster Power 46 and the E-Flite Power 46. None of them are 800kv.

How much difference is there in going from 800kv to say 670kv?

firemanbill
10-06-2010, 04:48 PM
I've never personally used a Rimfire, I have one that is in a nexstar that I got in a bundle deal but have never powered it up. Looks to be a good quality motor though, a buddy of mine has a few of them in smaller indoor type foamies and they perform very well.

firemanbill
10-06-2010, 05:23 PM
I just came home for lunch and looked at the Nexstar, I might be able to hook you up. It has the 42-50 800kv in it. Would that work on the Shoestring?

Its model number GPMG4700

Grasshopper
10-06-2010, 05:28 PM
Thanks a lot Bill but I think that might be a little underpowered for it. That's their .32 size equivalent. I need at least a .46 size. I have an E-Flite power 60 but I think that might rip the wings off it.

firemanbill
10-06-2010, 05:31 PM
Thanks a lot Bill but I think that might be a little underpowered for it. That's their .32 size equivalent. I need at least a .46 size. I have an E-Flite power 60 but I think that might rip the wings off it.

Got it, I was thinking the Nexstar was a 40 size plane, didn't look up the numbers.

On my original Shoestring which was the .60 size, I had a .90 sized motor in it! As you know, it flew really nice. try that 60!:D:cool:

Dr Kiwi
10-08-2010, 01:36 AM
I just bought a Great Planes 54" Shoestring and it calls for a Rimfire 42-60-800 outrunner. They pretty much go for around $80 everywhere. How is the quality of Rimfire and is there another motor comparable for less? I've looked at the Turnigys, Monster Power 46 and the E-Flite Power 46. None of them are 800kv.



I think the quality is reasonable... my beef with Rimfire is that the amp/watts limits suggested by Great Planes are extremely optimistic! I tested quite a range of Rimfires and every one of them heated up fairly fast if I came anywhere near these supposed limits.

Try an E-flite 60!

kyleservicetech
10-08-2010, 01:46 AM
I just bought a Great Planes 54" Shoestring and it calls for a Rimfire 42-60-800 outrunner. They pretty much go for around $80 everywhere. How is the quality of Rimfire and is there another motor comparable for less? I've looked at the Turnigys, Monster Power 46 and the E-Flite Power 46. None of them are 800kv.

How much difference is there in going from 800kv to say 670kv?

Check out the Hacker A40 series motors. Hacker has a wide variety of different motor "winds" for the same motor frame. Not cheap, but you get what you pay for. (http://www.aero-model.com/Hacker-Brushless-A40-10S.aspx) No I don't work for Hacker, but have a number of their motors ranging from an A30, A40's, A50's and an A60 class. And should you crash damage one, they can be repaired right in Arizona I believe.

What will really help you is one of those computer software programs such as www.motocalc.com (http://www.motocalc.com) that will give good information on what each motor can do.

Problem is, some of the motor vendors are way off on what their "KV" ratings and so on really are. Hacker is pretty close on their specs. And you can run them at their rated maximum power without concern.

The Hacker A40 and larger motors (as well as a few other motor manufacturers) have a large diameter ball bearing that supports the "Bell"
end of the motor. This type of setup makes it impossible for the "Bell" to twist out of alignment, allowing the motor magnets to hit the stator.

IMHO, any motor that runs over 100 watts per ounce of motor weight is really pushing the motor windings. Some of those Rimfire motors are pushing 150 watts per ounce of motor weight or even more. As a result, they run HOT. I've got a model that recommended one of those Rimfire motors. The model instructions tell you to NOT touch the motor after a flight because the motor could cause burns. :eek:

Dr Kiwi
10-13-2010, 01:18 AM
The oft-quoted "rule of thumb" is 3W/g = 85W/oz... I'm with Kyle... any company which suggests running their motors at 60C+ [even having allowed for in-flight cooling] is "away with the fairies".

Grasshopper
10-13-2010, 03:35 AM
Thanks for the info guys. Now I have another question. I'm looking at three different .46 size motors but don't know how to pick the right one. The Shoestring is 6.5 to 7 lbs AUW. The three motors are all from the same manufacturer but have different specs. They are:

42-60-600 3S to 5S Lipo
50-55-580 4S to 6S Lipo
50-55-700 3S to 5S Lipo

I'm leaning towards the 50-55-580 because I would like to run 6S but not sure if that's the right choice. Which ever one I pick, I have to buy new batteries so that's not an issue. I want it to be fast but not necessarily rip the wings off at over 100mph. I also don't want it to be marginal on speed and power either.

Any help here is appreciated.

CHELLIE
10-13-2010, 05:54 AM
Thanks for the info guys. Now I have another question. I'm looking at three different .46 size motors but don't know how to pick the right one. The Shoestring is 6.5 to 7 lbs AUW. The three motors are all from the same manufacturer but have different specs. They are:

42-60-600 3S to 5S Lipo
50-55-580 4S to 6S Lipo
50-55-700 3S to 5S Lipo

I'm leaning towards the 50-55-580 because I would like to run 6S but not sure if that's the right choice. Which ever one I pick, I have to buy new batteries so that's not an issue. I want it to be fast but not necessarily rip the wings off at over 100mph. I also don't want it to be marginal on speed and power either.

Any help here is appreciated.

Here you go Tom, here is a nice 800Watt powersystem with a 6 cell, on sale with a ESC for $75.00, its for up to a 8lb plane, the motors you linked to are a 60 size.

http://www.graysonhobby.com/catalog/images/Wegard-Large-Combo.jpg

http://www.graysonhobby.com/catalog/conversion-gh3520-p-667.html?osCsid=5c0986fe18ff96369f679986b731beab


<FORM method=post name=cart_quantity action=http://www.graysonhobby.com/catalog/glow-electric-conversion-gh3520-p-667.html?action=add_product><TABLE border=0 cellSpacing=0 cellPadding=0 width="100%"><TBODY><TR><TD><TABLE border=0 cellSpacing=0 cellPadding=0 width="100%"><TBODY><TR><TD class=pageHeading vAlign=top>0.50 Gas Conversion - GH3520-6 & 70A ESC
[Combo - 3520]
</TD><TD class=pageHeading vAlign=top align=right>Regular Price: <S>$94.99</S>
Special Price: $74.99
</TD></TR></TBODY></TABLE></TD></TR><TR><TD>http://www.graysonhobby.com/catalog/images/pixel_trans.gif</TD></TR><TR><TD class=main><TABLE border=0 cellSpacing=0 cellPadding=2 align=right><TBODY><TR><TD class=smallText align=middle><SCRIPT language=javascript><!--document.write('http://www.wattflyer.com/forums/images/imagecache/Wegard-Large-Combo.jpg

Click to enlarge (http://javascript<b></b>:popupWindow(\'http://www.graysonhobby.com/catalog/conversion-gh3520-pi-667.html\'))');//--></SCRIPT>http://www.graysonhobby.com/catalog/images/imagecache/Wegard-Large-Combo.jpg
Click to enlarge (http://javascript<b></b>:popupWindow('http://www.graysonhobby.com/catalog/conversion-gh3520-pi-667.html')) <NOSCRIPT></NOSCRIPT><!-- /************************************************** ****/// added by ensys - trupti 6/27/2008 -->


</TD></TR></TBODY></TABLE>
<META name=GENERATOR content="MSHTML 6.00.2900.3243"><HR>Powerful motor replacement for .40 - .50 size glow airplanes and sailplanes.
Your chose of 70amp ESC With or Without a BEC. (Read below for details)
GH GH3520-6 Motor Stats
Wire Winds / Turns: 12
Li-Po Battery : 4 / 7 cells
RPM per volt : 650
Max efficiency : 87%
Max efficiency current : 18 - 40 A
No Load Current / 10V : 1.6A
Max Current : 50A / 60 sec
Dimension : 42x47
Shaft : 5mm
Max Watts: <NOBR>600W (4S) - 700W (5S)</NOBR>
Continuous Watts : 800W
Weight : 298g
Recommended Model Weight : 8lbs
Recommended Propeller without gearbox: 13 x 8 or 14 x 7 APC Thin Electric



60 size power system
http://www.graysonhobby.com/catalog/conversion-gh4120-p-329.html

</FORM><FORM method=post name=cart_quantity action=http://www.graysonhobby.com/catalog/glow-electric-conversion-gh4120-p-329.html?action=add_product><TABLE border=0 cellSpacing=0 cellPadding=0 width="100%"><TBODY><TR><TD><TABLE border=0 cellSpacing=0 cellPadding=0 width="100%"><TBODY><TR><TD class=pageHeading vAlign=top>0.60 Gas Conversion - GH4120-07 & 70A ESC
[Combo - 4120]
</TD><TD class=pageHeading vAlign=top align=right>Regular Price: <S>$109.99</S>
Special Price: $89.99
</TD></TR></TBODY></TABLE></TD></TR><TR><TD>http://www.graysonhobby.com/catalog/images/pixel_trans.gif</TD></TR><TR><TD class=main><TABLE border=0 cellSpacing=0 cellPadding=2 align=right><TBODY><TR><TD class=smallText align=middle><SCRIPT language=javascript><!--document.write('http://www.wattflyer.com/forums/images/imagecache/Wegard-Large-Combo.jpg
Click to enlarge (http://javascript<b></b>:popupWindow(\'http://www.graysonhobby.com/catalog/conversion-gh4120-pi-329.html\'))');//--></SCRIPT>http://www.graysonhobby.com/catalog/images/imagecache/Wegard-Large-Combo.jpg
Click to enlarge (http://javascript<b></b>:popupWindow('http://www.graysonhobby.com/catalog/conversion-gh4120-pi-329.html')) <NOSCRIPT></NOSCRIPT><!-- /************************************************** ****/// added by ensys - trupti 6/27/2008 -->


</TD></TR></TBODY></TABLE><HR>Powerful motor replacement for .60 size glow airplanes and sailplanes
Motor Stats
Wire Winds / Turns: 14
Ni-Mh Battery : 12 - 16 cells
Li-Po Battery : 4 / 6 cells
RPM per volt : 610
Max efficiency : 85%
Max efficiency current : 20 - 40A (>81%)
No Load Current / 10V : 2.0A
Max Current : 55A / 60 sec
Dimension : 50 x 55mm
Shaft : 6mm
Max Watts: 1000W
Continuous Watts : 800W
Weight : 298g

</TD></TR></TBODY></TABLE></FORM><FORM method=post name=cart_quantity action=http://www.graysonhobby.com/catalog/glow-electric-conversion-gh3520-p-667.html?action=add_product>


</TD></TR></TBODY></TABLE></FORM>

CHELLIE
10-13-2010, 06:30 AM
Thanks a lot Bill but I think that might be a little underpowered for it. That's their .32 size equivalent. I need at least a .46 size. I have an E-Flite power 60 but I think that might rip the wings off it.

use your e flite 60 and prop it down and use i less lipo cell, it will work great and save you some dollars, its designed for 3D Planes requiring a 46 Motor

http://www.e-fliterc.com/ProdInfo/EFL/250/EFLM4060A-250.jpg

Power 60 Brushless Outrunner Motor, 400Kv

Key Features


Equivalent to a 60-size glow engine for 6 to 10 lb (2.7 to 4.5 kg) airplanes
Ideal for 46-size 3D airplanes up to 7 lb (3.2 kg)
Ideal for models requiring up to 1425 watts of power
High-torque, direct-drive alternative to inrunner brushless motors
Includes mount, prop adapters and mounting hardware
External rotor design—6mm shaft can easily be reversed for alternative motor installations
Slotted 12-pole outrunner design
High-quality construction with ball bearings and hardened steel shaft
Quiet, lightweight operation
Overview

The Power 60 is designed to deliver clean and quiet power for 60-size sport and scale airplanes weighing 6 to 10 pounds (2.7–4.5 kg), 46-size 3D airplanes up to 7 pounds (3.2 kg), or models requiring up to 1425 watts of power. It’s an especially good match for Hangar 9 .60-size warbirds like the Corsair 60 (HAN2575), P-47D Thunderbolt 60 (HAN2975), P-40 Warhawk 60 (HAN2850), P-51 Mustang 60 (HAN2375), P-51 Miss America 60 (HAN2775) and .46-size 3D planes such as the Hangar 9 Funtana 40 (HAN1975) or Seagull Harrier 46 (SEA3025).

Grasshopper
10-13-2010, 03:21 PM
Thanks for all the info Chellie! We can always count on you for digging up info. I've decided to keep the E-Flite power 60 for my 60 size Spitfire build. As for the Grayson Hobby combo, I have two new 80 amp ESCs so all I need is the motor. I also have new UBECs to go with them. I know a lot of people like Grayson Hobby, but I had nothing but bad experiences with them the two times I used them.

The sizes I listed above are from Value Hobby. They list them as .46 size.

http://www.valuehobby.com/product_details.php?category_id=30&item_id=338

CHELLIE
10-14-2010, 12:38 AM
Thanks for all the info Chellie! We can always count on you for digging up info. I've decided to keep the E-Flite power 60 for my 60 size Spitfire build. As for the Grayson Hobby combo, I have two new 80 amp ESCs so all I need is the motor. I also have new UBECs to go with them. I know a lot of people like Grayson Hobby, but I had nothing but bad experiences with them the two times I used them.

The sizes I listed above are from Value Hobby. They list them as .46 size.

http://www.valuehobby.com/product_details.php?category_id=30&item_id=338

That motor will work fine, its been listed as a 46 size motor but it really has the power of a 60 size, depending on how you prop it and how many lipo cells you use, and for that price, you cant go wrong :D Take care and have fun, Chellie

here is a nice 900 Watt motor from Heads up rc, its listed as a 46 to 52 size its a 4260-650 Kv motor

http://www.headsuprc.com/servlet/the-1652/4260-dsh-06-Outrunner-Brushless-Electric/Detail

groundrushesup
10-14-2010, 12:53 AM
I just bought a Great Planes 54" Shoestring and it calls for a Rimfire 42-60-800 outrunner. They pretty much go for around $80 everywhere. How is the quality of Rimfire and is there another motor comparable for less? I've looked at the Turnigys, Monster Power 46 and the E-Flite Power 46. None of them are 800kv.

How much difference is there in going from 800kv to say 670kv?


I was shopping for the same motor for the same plane - and got to see one up close at my LHS. It wasn't horrible, but it wasn't worth what they were charging either.

I ended up going with the 4020-10 Scorpion so I could have some prop flexibility.

I've done a few ground tests with it and it has gobs of power - its what got me my badge -

Scorpion 4020-10 @ 630Kv
Turnigy K-Force 100A ESC
APC 12x6 e-prop
Rhino 3700mAh 3S2P configuration (making a nominal 22.2v)

Peak Amps: 60.70
Peak Watts: 1358.4


I have yet to put it up in the air because I have had some serious problems with the aileron servos glitching and rebooting the AR7000 _ shelved it for a few months over the summer - but as luck would have it, last weekend I got it sorted with two new servos, and I plan to maiden it this weekend with buds Angler-Hi and Capt Easy there for moral support!

Grasshopper sir: if you are interested here is an email (http://www.wattflyer.com/forums/showpost.php?p=656336&postcount=48) that Lucien Miller sent me with some numbers on his rec's for this plane vis. the Sorpion line... I got permission to put it up on the Shoestring thread.


Josh

CHELLIE
10-14-2010, 01:23 AM
I was shopping for the same motor for the same plane - and got to see one up close at my LHS. It wasn't horrible, but it wasn't worth what they were charging either.

I ended up going with the 4020-10 Scorpion so I could have some prop flexibility.

I've done a few ground tests with it and it has gobs of power - its what got me my badge -

Scorpion 4020-10 @ 630Kv
Turnigy K-Force 100A ESC
APC 12x6 e-prop
Rhino 3700mAh 3S2P configuration (making a nominal 22.2v)

Peak Amps: 60.70
Peak Watts: 1358.4


I have yet to put it up in the air because I have had some serious problems with the aileron servos glitching and rebooting the AR7000 _ shelved it for a few months over the summer - but as luck would have it, last weekend I got it sorted with two new servos, and I plan to maiden it this weekend with buds Angler-Hi and Capt Easy there for moral support!

Grasshopper sir: if you are interested here is an email (http://www.wattflyer.com/forums/showpost.php?p=656336&postcount=48) that Lucien Miller sent me with some numbers on his rec's for this plane vis. the Sorpion line... I got permission to put it up on the Shoestring thread.


Josh

AR7000 glitching problems, take the Receiver apart and check for loose antenna wires. mount the receiver towards the rear of the plane away from esc servos etc, use a UBEC, a Capacitor may help too.

Spektrum AR7000 Beware!

http://www.flyinggiants.com/forums/showthread.php?t=47904

http://www.helifreak.com/showthread.php?t=88458

http://rc.runryder.com/helicopter/t376875p1/

<TABLE><TBODY><TR><TD class=td2 vAlign=top width=160 noWrap>lesodell3
Senior Heliman
Location: albion michigan


</TD><TD class=td2 vAlign=top>i am running the capasitor on my stuff and it helps with keeping the voltage even

http://rc.runryder.com/fastphoto/57916/SPM1600-250-8882-.jpg (http://javascript<b></b>:rrpp(2979733,1);)
</TD></TR></TBODY></TABLE>

guamflyer
11-25-2010, 10:47 AM
I read the beggining part here and see the question about the rimfires. actually i was a bit concerned myself so started experimenting a bit. I ended up using the same outrunner thats in the arf sr 22. it's the rimfire .10 1250kv. it calls for the 10x4 - 10x6 prop. what I did is instead of the 35amp esc I put in the silver series 45amp esc, used a 9x7.5 apc electric prop. got an honest 28-30 amps and 280-290 watts of power. My point is ,...bump up the esc from the recommended and add lots of cooling and those motors work really well. the plane was a 34" ws - 27" fuse and 26 oz auw. airfoil s6063..airplane PZL 130 Orlik..saddly it was lost to the sea about week ago..went to fast and lost sight of it. will be buying another rimfire soon..didn't cost too much and went fast...but like some guys say " if you want all out balls to the wall then you'll have to pay the piper"

guamflyer
11-25-2010, 10:49 AM
By the way ..if you feel that a motor is too strong...throttle back

av8djc
11-25-2010, 04:26 PM
Fresh off the test bench yesterday:

HK SK5055-580

4s 5000 16x8 Turnigy Type A Beech 63a 976w
5s 5000 15x6 Turnigy lite wood 60a 1172w
6s 5000 12x6 APC C2 49a 1137w

Using on a 6 lb. converted Astro Hog. Have flown the 5s and will test fly the others in a few hours :) I suspect the 5s is the best but then the 4s sure felt like a lot of thrust.

Grasshopper
11-25-2010, 04:32 PM
That's encouraging Dave. Is this the motor you tested?

http://hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=7071

av8djc
11-25-2010, 07:24 PM
That's encouraging Dave. Is this the motor you tested?

http://hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=7071

Yes grasshopper :) (always wanted to say that)

I flew it on 6s this morning and it was ok. It took off pretty fast and seemed to have OK thrust but not as good as the 5s setup. Unfortunately I forgot the prop to test the 4s and the 15x6 to fly my 5s so all I got was one flight. I also forgot to put the wattmeter in for the flight. :red: I guess the cold, wind, and son-in-law with grandsons distracted me. I'm really anxious to try the 4s setup though. I think it'll have a lot of thrust.

I think if you want to use 6s then perhaps go to this one to get lower kv:

http://hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=2102

I just ordered another SK like what I have because it already has a bad bearing. That could have been caused when I was testing and had some props on there that were not too kind to it. Despite the wattmeter if it does not sound very smooth it probably is not a good prop combination. More likely it was when the can moved forward a little because I forgot to check and locktite all the setscrews before the first run. Threre are a lot of bearing problems on the reviews for this motor though. I also bought one of the TR 50-55B-600 and might try that one instead of the SK. On the surface of it it looks like they would be pretty close to the same. I wish I would have bought a 50-55A-400 also.

I should explain that I now have 2each 5000ma Nano's in 3s,4s,5s. With the serial harness I can make the 6s,7s,and8s. The 7 and 8 will probably be used when I convert the larger glow airplanes. Now I have a shortage of the larger chargers.:(

Grasshopper
11-25-2010, 10:02 PM
Ahhh Massa,

I ended up buying this motor for my Shoestring. I haven't run it up yet to test it but I'll be running it on two 3S 30C 4000mAh packs in series for 6S.I'm starting with an APC 12x6e prop but may also try a 13x4e.

http://www.valuehobby.com/product_details.php?category_id=1&item_id=164