5" vs 6" Blackout style minis

[narcolepticltd]

Questions brewing in my head today... Obviously I don't have both versions to test with, so thought I'd pose this to those with experience on the frame. 3s or 4s, What is the difference in handling characteristics between the 5x4.5 bullnose on a 5" arm set up, and the 6x4.5 on a 6" arm set up? I'm not so concerned right now with amps and strain, etc, so let's just say the same motors/esc/battery combination... 2204/2300 cobras, 18a KISS.

I ask because a few months ago when I first started researching, everyone seemed to be crazy about 6" props, but lately I'm seeing a lot of folks running 5" or going back to 5" (and not for any kind of 'I only had 5" arms and couldn't afford to upgrade' reasons).

What are the pros and cons between the 2? do the 5" props handle better? more punch with the 6" props?

 

[cranialrectosis]

5" for 2300 on 4S.

6" for 2300 on 3S.

If you can afford them go with motors that can handle 2000kv on 4S with 6" rotors and you are getting the best of both.

 

[Mustang7302]

Most mini frames don't handle a six inch prop and people were left with less than good options. The HQ 5030 props made less thrust than GemFan 5030 props, and the HQ 5040 props made only slightly more thrust than the GF's for three times the cost. Cheap wins, especially when most people wouldn't be able to tell the difference between the GemFan and HQ props performance.

Enter the 5045 Bullnose. Now, all of the people who couldn't accommodate a six inch prop on their frame actually have a prop that is worth spending the money on. They provide a lot more speed and people start to notice how much nicer the rigid prop feels. It is a win win all the way around in the mini quad market space; which is why there is so much hype for them. Unless you're building a mini that is a pig (>800 grams), there isn't much of a need to go out of the way to make a five inch prop accommodate a six inch prop. Keep it simple, keep it clean, and have fun flying it.

On a more practical side of things, based on my experience and tests, the 2204 motors are actually too small for a 6045 prop. Yes they perform fine and don't burn up motors in most situations; but the 2204 size motor heat soaks and looses efficiency when you push it past 15 amps. This means that the motor wont achieve full RPM and you're leaving performance on the table. Even throwing more voltage at it only helps to offset the heat soak by so much. For 2300KV 2204 motors, the 5045 Bullnose props are -the- sweet spot for 3S (12A ESCs) and 4S (18A ESCs) performance. Less load on the motor, less heat, the same pitch, and more RPM achieved.

However, the numbers don't always tell a story well. A six inch prop has more surface area which makes them a little more stable by having better floating characteristics in the air. Just like a Tri feels more swooshy in the air with more fluid movement, the six inch props will have a better feel when you're just casually swooping around and doing light acro flying. But this is totally subjective to each pilot. Given that my two casual fun flying copter setups run 1806-2300KV/6020 Prop/3S and 2204-1960KV/6045 Prop/3S setups should help indicate my preference.

 

[Cyberdactyl]

I much, oh so much, prefer HQ0645s and 4S on my FPV-mini. I posted a few months ago, I was getting in the low 50's mph on 3S and have since switched to 4S now that I am comfortable flying it. I haven't measured what I can achieve with 4S, but I'm am fairly sure it's in the upper 60's, maybe low 70's.

But here's another issue that could make the decision for you that I ran into a couple weeks ago. . . even if your mini can accept 6" props and 4S. My local FPV racing club only allows 0530 props, 3S and motors no larger than 1806, to keep the racing field level. So, I end up just watching, because my mini breaks the motor size. And putting 0530s on my little 2600KV monsters would be like putting space saver tires on a GT Mustang. The spring league is starting in a few days, and I may try and do something with the little Dragonflys I have.

 

[joshuabardwell]

For what it's worth, Soma found that 6030 was the sweet spot for the SunnySky 2204 2300kv. More efficient than any 5" prop with more thrust overall. The 6045 produced the most thrust, but were definitely at the edge of the motor's capacity. However, the HQ 5040 were darn close to the 6030, with only 50 grams less thrust, and 4.0 g/W instead of 4.5. Nevertheless, at least according to these test results, the reason to go with 6" is that you get more thrust for fewer watts--a win all around if you don't mind the extra size and the change in flight characteristics.



Also, notice that the 6x3 and the 5x4 props produce almost identical RPM--around 21,000. The 5x3 produced about 10% more RPM than the 6x3, so the difference is in the pitch. But overall, the props are very close to the same RPM. The motor is not being significantly loaded by either prop. 75% to 80% of no-load RPM is a good place for wringing max performance out of a motor in my (limited) experience.

http://www.rcgroups.com/forums/showthread.php?t=2112708

 

[cranialrectosis]

Having flown my WarpQuad with 2300kv SunnySkys and 5030 and 6030 rotors on 3S I can state with confidence that 6" rotors under these circumstances are superior for flight. You have wider control surfaces allowing for better control.

Bump up to 4S and the game changes but at 3S 6" rotors are more fun to fly.

 

[jhitesma]

Last Friday I dusted off some HQ 5x4 and 6x3 props I had and gave them a go on my 230 twitchity with 1806 DYS motors.

I usually fly 6x4.5's even though I know they're really pushing the limit on these motors - but I've yet to run into any major heat issues and I frankly just love the way it flies on the 6" props. Even if it means risking burning up a motor since the DYS motors are so ridiculously cheap.

But...I'm out of FC 6x4.5's right now and felt like letting off some steam and knew I'd be doing a lot of crashing so I didn't want to use up the HQ 6x4.5's I have on hand.

I had initially bought the 5x4 and 6x3's when I had my friends warp (SS2204's still 3s like my twitchity) on loan for a few months so I could feel out various prop options. I quickly found I loved the feel of the 6x4.5's and the others have been collecting dust since.

So it was interesting to give them a try on my own quad.

I found I actually liked them more than I expected. I had tried them before when I was running BS12 ESC's with blheli but the drop in performance and the high price of HQ's compared to FC's convinced me to go back to the FC 6x4.5's rather quickly. This was my first time trying the "smaller" props after switching to KISS esc's

To be honest I quiet enjoyed them. I think I liked the 5x4's more than the 6x3's...they felt very similar in the air but the 5x4's felt a little more aggressive while the 6x3's were more floaty. Plus the 5x4's being shorter were harder to break and lasted through more crashes.

But neither the 5x4 nor the 6x3 could live up to the 6x4.5's for performance and more than once I crashed because I didn't have the power reserves and response I'm used to.

That said...I'm really thinking about grabbing some more 5x4's (or some 5" bullnose which weren't available last time I did a big order of HQ props) because while they weren't as aggressive they were still a lot of fun and sometimes it's nice to turn things down from 11 a bit

 

[C0d3M0nk3y]

I haven't flown 5 inch and 6 inch props on the same frame, so I can't really give you a comparison between them. I can say that I'm loving the Blackout with 5 inch props though. I say pick up a couple sets of 5x4.5s and throw them on your mini tri to play around with.

Here's the difference in size between the HQ 6x4.5 and HQ 5x4.5 bullnose props:

 

[FinalGlideAus]

I'm just waiting to see everyone's response before I weigh in on this

Considering I have 3s, 4s and 6s quad running 5" and 6" setups I think I have a reasonable grasp on what does and doesn't work.

Oh and Soma, Strepto and myself were the ones responsible for bringing both the 5x4.5 bullnose and 6x4.5 props into the mini quad world. Just saying...

 

[narcolepticltd]

Oh and Soma, Strepto and myself were the ones responsible for bringing both the 5x4.5 bullnose and 6x4.5 props into the mini quad world. Just saying...

So... this is all YOUR fault? I knew it!

Although there are quite a few replies here with great info, I'm hoping it doesn't turn into a numbers thread. I'm honestly just curious why one would prefer one over the other. I know you're currently running 5x45 bulls on 4s when you easily have the choice of running larger arms and 6x45s, and I've seen others (ummagawd) mention they were 'back to 5"' on other videos as well.

I'm just trying to plan out my next build, and want to get it right. If I have to buy 2 sets of arms and 2 sets of props and motors just to test it out I will... but hopefully the combined opinions here will sway me in one direction or the other

 

[FinalGlideAus]

Right so it's lunch time now. I didn't really want to type this out on my phone but oh well .

3s or 4s? Well I find 3s a waste of time so let's just talk 4s to simplify things. It's first worth noting that you can't use the same môtor for both props. 2300kv is best for 5" on 4s and 2000kv is best for 6" on 4s. Sure you can fly with different combos but taking all the prop, efficiency weight blah blah blah into account you come back to those figures. I also am comparing 5x4.5 bullnose and 6x4.5 props as I don't see the point in including any of the others.

With the above setups in mind you will getting higher Rpm's, higher top speed and a quicker response with 5" but a torque'r feel and slightly more thrust with a 6". Think of a GoKart. The 5" is like having an ever so slightly higher gear and thex6" is like having a ever so slightly lower gear.

On the ha handling side, the 5" feels more nimble but the 6" is more refined and smooth. So if flying proximity around the trees or a really tight race track or hardcore Acro is your thing then a 5" setup would suit best. If you already have a 5" then try a 6x4.5 setup with Cobra 2204 1960kv motors and use the 1800 packs you already have.

As far as 2204's not handling 6" props on 4s well that depends on the KV used. 2300 is too high but that is the case no matter what môtor you use. The Cobra 2204 1960kv is perfect for 6" on 4s. Boris.B uses it, Charpu uses it and so does Metal Danny. Metal Danny was one of the first to try that combo on 4s. Of course yes you can go 2206 or 2208 and get more thrust and higher rpm and therefore top speed but the extra weight makes the quad handle like a tank in the corners. If you're like a lot of guys out there that just scoot around in the open fields or race on simple tracks with nothing technical then that will be fine but it becomes noticeable when doing decent proximity. There is a reason why Danny, Boris and Charpu have gone back to the 2204 motors. I have an actual pile of motors consisting of MN1806 2300kv, SS2204 2300kv, cobra 2204 2300kv, cobra 2204 1960kv, MN2206 2000kv, MN2206 2350kv and MN2208 2000kv and they are just my pile that I have tested so I think I've covered most of the bases. Combine that with all of Soma's thrust testing and my friends testing and we've pretty much tested every type of combo.

 

[narcolepticltd]

Right so it's lunch time now. I didn't really want to type this out on my phone but oh well .

3s or 4s? Well I find 3s a waste of time so let's just talk 4s to simplify things. It's first worth noting that you can't use the same môtor for both props. 2300kv is best for 5" on 4s and 2000kv is best for 6" on 4s. Sure you can fly with different combos but taking all the prop, efficiency weight blah blah blah into account you come back to those figures. I also am comparing 5x4.5 bullnose and 6x4.5 props as I don't see the point in including any of the others.

With the above setups in mind you will getting higher Rpm's, higher top speed and a quicker response with 5" but a torque'r feel and slightly more thrust with a 6". Think of a GoKart. The 5" is like having an ever so slightly higher gear and thex6" is like having a ever so slightly lower gear.

On the ha handling side, the 5" feels more nimble but the 6" is more refined and smooth. So if flying proximity around the trees or a really tight race track or hardcore Acro is your thing then a 5" setup would suit best. If you already have a 5" then try a 6x4.5 setup with Cobra 2204 1960kv motors and use the 1800 packs you already have.

As far as 2204's not handling 6" props on 4s well that depends on the KV used. 2300 is too high but that is the case no matter what môtor you use. The Cobra 2204 1960kv is perfect for 6" on 4s. Boris.B uses it, Charpu uses it and so does Metal Danny. Metal Danny was one of the first to try that combo on 4s. Of course yes you can go 2206 or 2208 and get more thrust and higher rpm and therefore top speed but the extra weight makes the quad handle like a tank in the corners. If you're like a lot of guys out there that just scoot around in the open fields or race on simple tracks with nothing technical then that will be fine but it becomes noticeable when doing decent proximity. There is a reason why Danny, Boris and Charpu have gone back to the 2204 motors. I have an actual pile of motors consisting of MN1806 2300kv, SS2204 2300kv, cobra 2204 2300kv, cobra 2204 1960kv, MN2206 2000kv, MN2206 2350kv and MN2208 2000kv and they are just my pile that I have tested so I think I've covered most of the bases. Combine that with all of Soma's thrust testing and my friends testing and we've pretty much tested every type of combo.

All that from your phone? Your videos aren't the only thing that's spe-

Ok jokes aside, your comparison here made the gears click into place perfectly. This is the kind of understanding that I was looking for and will definitely move me in the right direction much faster. Much appreciated!

As are all of the replies in this thread. Thanks gang!

 

[C0d3M0nk3y]

This is the kind of understanding that I was looking for and will definitely move me in the right direction much faster.

So are you going to tip your hand and tell us what you're planning on building?

 

[narcolepticltd]

So are you going to tip your hand and tell us what you're planning on building?

An ImmersionRC Vortex

 

[FinalGlideAus]

In keeping with the thread subject, its worth mentioning that the Vortex is coming out with 1806 motors and they won't handle bullnose 5x4.5 or bigger props on 4s for very long. It also only has 12a ESC's. I can see an updated version with 20a esc's and 2204 2300kv motors coming out at some stage but not for this release. All that said, the power of the 1806 on 4s with 5x4 props may be more than enough for you. How much power is good enough is up to the individual. Of course you can do what I have done and put 2204 1960kv Cobras on the vortex with bullnose prop and 4s but that requires another môtor purchase. The 12a ESC's are handling it fine though..

 

[narcolepticltd]

In keeping with the thread subject, its worth mentioning that the Vortex is coming out with 1806 motors and they won't handle bullnose 5x4.5 or bigger props on 4s for very long. It also only has 12a ESC's. I can see an updated version with 20a esc's and 2204 2300kv motors coming out at some stage but not for this release. All that said, the power of the 1806 on 4s with 5x4 props may be more than enough for you. How much power is good enough is up to the individual. Of course you can do what I have done and put 2204 1960kv Cobras on the vortex with bullnose prop and 4s but that requires another môtor purchase. The 12a ESC's are handling it fine though..

I was attempting to be clever, but did almost start a build thread for a vortex

I am definitely still split down the middle on going with the vortex first, or going the blackout mini H (the black out was what inspired this thread). Hearing that the current escs on the vortex are handling the 2204 1960kv cobras and bulls on for 4s is definitely swaying me in that direction though... and there's an IRC vendor that's local to me here, who likely hasn't sold all they've ordered via pre-orders yet.

were you running 1300 nano-techs or the larger high amp 1800's on that vortex set up?

EDIT: nevermind, I already know the answer to that... I think the 1800s would serve me better in the long run anyways =)

 

[narcolepticltd]

I was initially kidding about the vortex, but FGA's 2204/1960 mod + my local hobby having 100 of them on order just spent a portion of my paycheck... I even had to pay sales tax! Picking up Saturday... and much more money will be spent on goggles, new batts, a gopro, googly eyes, etc. (gonna start out with what I have LoS, and throw a 1.3mah 45-90c on it with wimpy props just to dork around with).

if/when 20a escs are available, I'll probably push some 6x4.5s on here, and plan the blackout with 5" arms and 5x4.5 props, 2300kv

Sig updated...

 

[C0d3M0nk3y]

. Of course you can do what I have done and put 2204 1960kv Cobras on the vortex with bullnose prop and 4s but that requires another môtor purchase. The 12a ESC's are handling it fine though..

Hmm... that's interesting. I do have a spare set of 2204 1960KVs. I may try that after I tear through the 5x4 props I have.

 

[narcolepticltd]

Hmm... that's interesting. I do have a spare set of 2204 1960KVs. I may try that after I tear through the 5x4 props I have.

I may order a set/spares of those cobras next pay period... if not, definitely in the plans. I'm sure the t-motors will tide me over just fine on 5x4s for at least a while (need to decide on goggles)

 

[jipp]

2204 are the next up from 1806s right?

the motor sizes are gonna take time to learn..

chris.