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Post by ginginho on Feb 23, 2010 14:14:45 GMT 1
IMO the 3536 is way too much power for a SC, you may get problems fitting it under the cowl and balancing the aircraft may be fun too. Something around 230-250w (into the system, assume 70% efficienc >:(y) will give you performance that will put a smile on your face (vertical clime for a couple of 100 feet) without it being stupid. I agree that the 3536 is a stupid amount of power for the cub, but it's not really an uncommon motor for revheads to upgrade their cub with, the Turnigy 3536 is particularly popular. I've seen motor mounts to fit them to the cub on ebay, and here's one I just found on google: www.customrcparts.com/motorMountDetail.php?productID=100010&&bannerID=2That's a really nice looking mount by the way! It is indeed with the built in thrust angle. Machined from Aluminium. Shame it's out of stock and the weight is not listed. I have a 3536 in my Gemini which weighs around the same as a SC so I know how these motors perform. The SC is not built to take that much power and it's unlikely that you'll get any major performance difference due to the draggy airframe. Powerful enough to prop hang? Most certainly, but who'd want to do that with a SC? The control surfaces are probably not big enough to allow it to be held anyway. I've heard of many people that have had to add a lot of weights to the front of their cubs after upgrading to 28-30 motors because they're just so light! The stock motor and gearbox weighs 145g, and the 35-36 motors weigh from 105-110g, so that still leaves you 40g for a speed controller and motor mount. I think I'd rather have a larger motor and just prop down as necessary than have to add weight to the nose of my plane, the only downside is that with a larger motor your battery life would be a bit less, cos you're using extra power to spin the heavier motor. I bet that mount is best part of the 40 grammes you have left over, and a 40A ESC (most go for these because of the intergral 3A SBEC) are between 30 and 40 grammes themselves. Even the wooden mounts you listed weigh a finite amount. To keep the same sort of weight up front as the stock setup, you'll need a motor weighing around 70-80 grammes. [snipped] Another thing to be mindful of is what type of outrunner you get. With outrunner motors, the whole outside of the motor (the bell) spins, not just the shaft. The tricky thing is that some motors have the shaft sticking out the bell side of the motor (the side that spins), and some have the shaft sticking out the opposite side of the motor where the wires go in (which is stationary). You can get mounts for either type really, but generally speaking it's easier to get the type with the shaft sticking out the same side as the bell. Erm, didn't I mention that? Be aware that all the 2800 and 3500 motors have the shaft exiting the motor out of the rear (for behind firewall mounting or cage mounting), although they come with an adaptor that allows it to be used the other way round (check the pictures on the site). |
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Post by SCC on Feb 23, 2010 14:32:57 GMT 1
Another thing to be mindful of is what type of outrunner you get. With outrunner motors, the whole outside of the motor (the bell) spins, not just the shaft. The tricky thing is that some motors have the shaft sticking out the bell side of the motor (the side that spins), and some have the shaft sticking out the opposite side of the motor where the wires go in (which is stationary). You can get mounts for either type really, but generally speaking it's easier to get the type with the shaft sticking out the same side as the bell. Hi Dill All outrunners that I have owned including the motors in your post, the shaft can be pushed through to suit your configuration. I like using the collet type prop adaptors as you have a little bit of adjustment on the shaft. |
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Post by vegatron75 on Feb 24, 2010 7:47:03 GMT 1
I was able to go brushless and not add any weight to the plane. I used a Headsuprc/Value Hobby 3530-11, custom wood mount and 40 amp hobbywing esc in the cowl. Almost exactly the same weight as the stock set-up. This combo w/ a 10x6 gws dd prop draws 20 amps and produces around 226 watts. Attachments:
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Post by Dillzio on Feb 24, 2010 8:41:02 GMT 1
Erm, didn't I mention that? Be aware that all the 2800 and 3500 motors have the shaft exiting the motor out of the rear (for behind firewall mounting or cage mounting), although they come with an adaptor that allows it to be used the other way round (check the pictures on the site). Well, yeah, but this guy is a rookie. You can't just assume that the newbies will know what you're talking about, I remember when I was learning about outrunners from this forum and boy was I lost! I felt a simpler explanation with some pretty-pictures would help the poor fella from getting too overwhelmed. Can anyone comment on which is more crash resistant: The collet type prop adapter that connects to the shaft, or the type that bolts onto the bell of the motor? I figure the former would be more easily damaged, but easily repaired with the replacement of the prop shaft, and the latter would be stronger, but would trash the motor in a more severe crash. Is there any truth to my theory? |
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Post by ginginho on Feb 24, 2010 10:37:21 GMT 1
I was able to go brushless and not add any weight to plane. I used a Headsuprc/Value Hobby 3530-11, custom wood mount and 40 amp hobbywing esc in the cowl. Almost exactly the same weight as the stock set-up. This combo w/ a 10x6 gws dd prop draws 20 amps and produces around 226 watts. That's very similar to how I did mine (I have perspex rather than wood as the plate) which I prefer as it gives the option of being able to adjust the thrust angle with the leg bolts. We even used the same ESC! That's a nice tidy job you've done there. |
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Post by ginginho on Feb 24, 2010 10:53:00 GMT 1
Can anyone comment on which is more crash resistant: The collet type prop adapter that connects to the shaft, or the type that bolts onto the bell of the motor? I figure the former would be more easily damaged, but easily repaired with the replacement of the prop shaft, and the latter would be stronger, but would trash the motor in a more severe crash. Is there any truth to my theory? The former is dependant on what quality and diameter the shaft is. Some are quite bendy whereas others are machine steel and hence it's more likely that the motor will be trashed before the shaft is bent/broken. Although the shaft can be changed, it's not always an easy job. I've heard of people wrecking a motor whilst trying to remove a bent shaft. I have the latter type on my SC (similar to the picture posted by Vegatron above). The diameter of the shaft on this is larger than the normal shaft sizes, so generally some drilling of props is required to allow them to fit. It's made of aluminium and can be broken. I know, I broke one on the first flight after going B/L due to a reversed elevator and going in at WOT after launch (see my avatar).....  Replacements are not always readily available, however there are common sizes used between many of the brands (they probably are all made in the same Chinese factory. XYH, Turnigy, Purple Power and a couple of other brands certainly are). A replacement is about the same price as a cheapo servo. Remove crashing from your flying day and then there's no concern as to which is better.  |
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foo
Flight lieutenant
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Post by foo on Feb 24, 2010 12:24:58 GMT 1
Yes, the black is required. A 4A SBEC should be sufficient for a lot of installations, unless you are planning on running lots of big servos on many control surfaces. What sort of thing are you looking at? I was looking at getting an e-flite Extra 260 480 ARF, but I've since found a very cheap second hand e-flite mini Edge 540 which I'm buying. 3rd plane and counting! Once you start... Cubs should carry health warnings - "will cause addiction!" |
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Post by ginginho on Feb 24, 2010 14:35:34 GMT 1
Yes, the black is required. A 4A SBEC should be sufficient for a lot of installations, unless you are planning on running lots of big servos on many control surfaces. What sort of thing are you looking at? I was looking at getting an e-flite Extra 260 480 ARF, but I've since found a very cheap second hand e-flite mini Edge 540 which I'm buying. 3rd plane and counting! Once you start... Cubs should carry health warnings - "will cause addiction!" Is it one of these? If so, the 4A within the ESC will be more than enough, a 3A SBEC would probably do for the 4 sub-micro servos. |
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Post by Dillzio on Feb 24, 2010 15:43:36 GMT 1
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foo
Flight lieutenant
Posts: 50
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Post by foo on Feb 24, 2010 15:48:03 GMT 1
Is it one of these? If so, the 4A within the ESC will be more than enough, a 3A SBEC would probably do for the 4 sub-micro servos. That's the one  |
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foo
Flight lieutenant
Posts: 50
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Post by foo on Feb 24, 2010 15:50:42 GMT 1
Bought one of those Skywing ESC's off ebay, got it with no programming instructions. Found some on the net eventually, but now I'd rather not use it anymore I'd rather just get a turnigy motor and esc from HK. |
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Post by vegatron75 on Feb 24, 2010 20:35:34 GMT 1
I was able to go brushless and not add any weight to plane. I used a Headsuprc/Value Hobby 3530-11, custom wood mount and 40 amp hobbywing esc in the cowl. Almost exactly the same weight as the stock set-up. This combo w/ a 10x6 gws dd prop draws 20 amps and produces around 226 watts. That's very similar to how I did mine (I have perspex rather than wood as the plate) which I prefer as it gives the option of being able to adjust the thrust angle with the leg bolts. We even used the same ESC! That's a nice tidy job you've done there. Thanks, I do what I can.... What is this perspex? Never heard of it. The esc is nice, value hobby has them pretty cheap, switchmode bec too. |
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Post by Dillzio on Feb 24, 2010 22:17:57 GMT 1
Perspex is a transparent hard plastic, it's often used to line skylights, or used in place of glass in sports arenas because it can bend and won't shatter like glass.
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Post by seabass001 on Mar 10, 2010 23:55:04 GMT 1
Hey Vegatron.. I really like how you mounted your setup. Keeping the ESC cool by mounting it in the cowling is genius. Everyone has giving me a ton of info and I really appreciate it.
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Post by Dillzio on Mar 11, 2010 9:03:01 GMT 1
yeah, that is a nice mount. I might try the same thing with a piece of aluminium instead of wood.
What are the long plastic peg things you're using as spacers, and where do you get them from?
cheers :-)
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