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View Full Version : Props, props, and more props



RTRyder
02-03-2011, 02:34 PM
This afternoon I got a chance to try out the Hoverfly quad with the 11 x 4.7 APC props on it and as expected they do generate a lot more lift, I was hovering a little below 1/2 throttle instead of the just slightly above when fully loaded on the 10 x 5 Graupners. It flew fine, the extra inch of prop length didn't seem to bother the motors so it appears they can handle it though it would probably be better with lower KV motors so they spin a little slower.

Big difference came in when a gust of wind hit it, the extra lift has a much greater effect on the quad when it's windy, bounces all over the place where it only had a little twitch to it with the smaller props so I think these are too much for the quad without adding some weight to keep it stable. Good to know I can up the prop size that much if I do need to lift more payload though.

Just as I got done with that I got an email notification that the 11 x 5 Graupners I've been waiting for are back in inventory, figures, I just bought the APC 11 x 5 set because it looked like it was going to be a while before the Graupners would be available and as soon as I got the APC in hand the Graupners show up. I immediately went to the website and ordered the 11 x 5's with plenty of spares, I can't wait to try them on both the Hexa and Hoverfly.

The Graupners have a very different blade profile than the APC so I think they will work out on the quad, on the Hexa I need the extra lift as right now it's very much at the limit of what it can lift on the 10 x 5 props.

So now I'll have a bunch of the Graupner 10 x 5, a set of APC 11 x 4.7 plus a couple spares, and a full set of Graupner 11 x 5 plus spares, looks like I'm set for the season on props now.

Speaking of the Hexa, I just checked tracking and found the new flight controller board is out for delivery, fantastic since I only ordered it two days ago and the weather between here and where it's coming from is crap right now. The USPS delivers the goods as promised! :)

Ken

Droider
02-04-2011, 03:32 AM
Ken whos got the Graupners in stock?

RTRyder
02-04-2011, 07:34 AM
Ken whos got the Graupners in stock?

Electricwingman does if I didn't buy their entire stock...;)

Ken

Droider
02-04-2011, 12:37 PM
Yup.... you have;)

RTRyder
02-04-2011, 10:06 PM
According to their website they still have 11 x 5 right and left in stock, that's all I bought this time, I've got plenty of 10 x 5's on hand already :D

Ken

DennyR
02-05-2011, 01:53 AM
Ken
I did a little testing of props this week and found some interesting things. The 14x4.7 does produce the best lift efficiency on the MK3538 motor on a test rig. BUT it does make the model very sensitive in throttle response. I did my tests on a small Minsoo Kim Quad with the 3538's fitted. Way overpowered but the idea was to gradually increase the payload and see what props worked best. In the lightest possible configuration it was almost unflyable due to the oversensitive throttle, however by cutting the 14x4.7 down to 11.5 dia. it was flying really well. So the fact is that you can have too much prop efficiency. As the weight got higher, so the increase in prop diameter improved the response. But even at very high payloads the full 14 dia was still too much.

I also tested the APC 13x6.5 and found that the pitch is too high at any dia. It was way down on endurance due to being very inefficient. It produces a lot of noise which indicates that it is stalling most of the time.

Droider
02-05-2011, 04:12 AM
Sorry Ken you didnt! I just got my order on! but no LH 10x5 :(

RTRyder
02-16-2011, 09:00 PM
The Graupner 11 x 5 props arrived today, twelve days from shipment in the UK to my front door, I guess they didn't go airmail!

Got a set mounted on the Hexa before it got dark and managed a short hop out in front of the house, wasn't enough to really notice much difference so far. Friday is supposed to hit temps in the 50's, I may take a long lunch break and see if I can sneak over to a nearby baseball field and get in a test flight or two.

I will say the parameter setting changes have made a world of difference in stability on the Hexa, it was gusting pretty good out there and it held position really well, have to wait and see how it does in regular flight.

Ken

Droider
02-17-2011, 06:49 PM
I get mine next day from them.. they are only 30 miles from me though! :cool:

RTRyder
02-17-2011, 07:13 PM
Got a chance to fly the Hexa with the new props at lunch time today, set the TX timer for 8 minutes and flew it around, tried out GPS hold, Altitude hold, and both at once. Seems to be working pretty good, motors were just barely warm at the end of the flight as were the batteries, I put back 3300 mA into each 5000mAh pack once they cooled down. If I get a chance tomorrow I'll swap back to the 10 inch Graupners and do the same flight to see how the battery usage compares.

Looking at the video out of the GoPro from the flight, I've still got some work to do dialing in the camera mount.

Ken

Bartman
02-17-2011, 07:20 PM
ken,
new graupners and spacers are finally all here and ready to go. i'm thinking a little thin CA glue at the base of the prop would be a good idea to lock the spacers to the props to keep things from spinning free under load. any opinion on that?
thanks,
bart

RTRyder
02-17-2011, 09:39 PM
ken,
new graupners and spacers are finally all here and ready to go. i'm thinking a little thin CA glue at the base of the prop would be a good idea to lock the spacers to the props to keep things from spinning free under load. any opinion on that?
thanks,
bart

So you've probably noticed the spacers are longer than the prop hub is thick, glue is not the answer here. It's a bit of a PITA, but what I do is take a file and carefully bring the spacer down to the same thickness as the hub, once you do that you can tighten the prop nut down on the washer (you do have the large hub sized washers that go between the nut and prop don't you?) and the prop will be nice and snug on the adaptor. All the spacer does is keep the prop centered on the spindle, it has nothing to do with keeping the prop from spinning on the adaptor, so file the spacers and if you don't have the proper washers to go on top of the prop you shouldn't fly until you get some, it's really the only way to make sure the prop is secure and won't slip on the shaft.

Another reason I never glue the spacer is if you break a prop the spacer can easily be popped out and used in the replacement.

Ken

Bartman
02-17-2011, 09:57 PM
too late. i don't have the prop washers you're talking about, only star washers to use as lock nuts. they don't cover much beyond the spacers so i glued the spacers. i'm going to order more of everything as soon as i get a fix on which props i like best. xoars should be here in a few weeks hopefully with a 5mm prop bore already taken care of at the factory. i requested it, we'll see if i get it.
flying is almost certain tomorrow with the okto/camera combo. wish me luck.
bart

baker55
03-28-2011, 03:04 PM
I'm using the stock props APC 12" that my hexa kit came with. They seem to work well but I don't have anything to compare them with. If I ever get my camera mount I will be lifting a 7D so would these blades be ok? SM

Droider
03-28-2011, 03:19 PM
Got to say I love my Graupners, even in fast decents they seem to keep stable and are no where near as noisy as the APC one my ADX3 came with.

I got mine here

http://www.electricwingman.com/propellers/graupner/elektro-prop.aspx

baker55
03-28-2011, 03:54 PM
I like noise... which size Graupners would replace 12 APC?

Droider
03-28-2011, 04:08 PM
Ahh not sure they go that big.. check out the website I linked you to. Drop them a line they are usually back to you very quickley. There are some new 12" carbon ones out in Australia.. will find the link

Dave

RTRyder
03-28-2011, 04:35 PM
Ahh not sure they go that big.. check out the website I linked you to. Drop them a line they are usually back to you very quickley. There are some new 12" carbon ones out in Australia.. will find the link

Dave

Aerobot has them, http://www.aerobot.com.au/shop/index.php?_a=viewProd&productId=92 or Quadrocopter in the US is stocking them as well http://shop.quadrocopter.us/Aerobot-12x38-Carbon-Fiber-Propeller-Pair_p_303.html. Be prepared to dig deep if you need 6 or 8 of them, about $50 US a pair...

As for Graupner, unfortunately they do not (yet) make what we need in a 12 inch size. I just put a set of APC 12 x 3.8 on the Droidworx Heavy lift and find they work much better than any of their smaller sizes, of course right now they're the only game in town so like 'em or not they'll be staying on the HL until something better comes along.

Ken

Bartman
03-28-2011, 05:37 PM
I received my shipment of Xoar wood props a couple of days ago and I think they're going to be just about perfect. The blade is a little deeper in chord in the outboard half and just about the same as the Graupners in the inboard half. That little bit of extra bite in the outboard half should make them close to perfect as I thought the Graupners gave up a little too much lift when I first went to them. The Xoars are also noticeably stiffer in the tips than the Graupners.
Xoar makes a variety of sizes of the PJA and PJA-P props so I suspect there is a 12" version. I'm probably going to special order a batch of the 11"x5" props for my X650 if anyone is interested.
Bart

Bartman
04-12-2011, 09:18 PM
Xoar props arrived and they're mounted but I can't get outside between rain and wind. It sounds like RTRyder has his in place but suffered a mishap. Did you like the props Ken before the mishap?
I'm hoping to get outside tomorrow to finally test them out.
Bart

RTRyder
04-12-2011, 09:50 PM
Xoar props arrived and they're mounted but I can't get outside between rain and wind. It sounds like RTRyder has his in place but suffered a mishap. Did you like the props Ken before the mishap?
I'm hoping to get outside tomorrow to finally test them out.
Bart

Well from the slightly more than 60 seconds of flight time I got on them before the MK went bonkers they seemed to be OK. One thing I noticed for certain is they're a LOT quieter than the Graupners, these have a kind of whispering sound where the Graupners sound like a swarm of angry bees.

They do survive minor mishaps quite well too! I can't find a mark on any of them though they will get a very close inspection with a magnifying glass before they fly again. Currently the Hexa is on the bench with no props on the motors for testing purposes, the flight logs show nothing unusual and everything checks out in MKtool, RX quality was between 189 and 200 for the duration of the flight so I know it wasn't loss of signal... ???...

Ken

FOX222
04-12-2011, 10:12 PM
What happened Ken?

Bartman
04-12-2011, 10:18 PM
i spun mine a little in the office last night and they did seem quiet. will fly them asap.
bart

RTRyder
04-12-2011, 10:20 PM
What happened Ken?

See my update in the Mikrokopter firmware update .84 thread...

Ken

Droider
04-13-2011, 01:51 PM
Where do the Xoar props come from? What size you guys got?

Bartman
04-13-2011, 06:45 PM
Droider,
I did a special order from www.bobshobbycenter.com, the US Xoar distributor. We are flying the 10x5 PJA and PJA-P props and though I only got to fly for about eight minutes today, I definitely think I'm making more lift than the 10x5 Graupners. All in all, I'm pretty happy but we'll see how they hold up being wood.
Bart

1001 Copters
04-15-2011, 09:39 AM
Hi, I received yesterday a new batch of 13x6.5" XOAR precision pair.
As requested to XOAR they send me several size (13x7,13x5,14x4,14x6).
I met Mr fourdan at the beginning of this week, he's the creator of the scoprion calculator freeware and He's testing most of the brushless that comes on the market.
I asked him lots of advice about testing motors and prop and we will soon publish the test we will make with:
pulso 2814/22
MK3538
AXI2814/22
AHM motor
APC 12x3.8
XOAR prop 2 blades and 3 blades.

I want to find the best combo for heavy lift multirotors ;)

Bartman
04-15-2011, 11:50 AM
what props?? if you can answer that question, you'll be my hero.
i put five flights on the new Xoar props yesterday and i think they're step above the same size graupners. it'll be interesting to see what you come up with.
bart

CopterCam
04-15-2011, 04:11 PM
This Forum is attracting innovative and forward thinking individuals who are willing to share their findings and offer words of wisdom to newcomers. Glad I stumbled across this Forum, I can think of other forums where newcomers questions are treated with disdain. I have a good feeling about the future development of this Forum ?

Sid

jes1111
04-15-2011, 05:31 PM
Hi, I received yesterday a new batch of 13x6.5" XOAR precision pair.
As requested to XOAR they send me several size (13x7,13x5,14x4,14x6).
I met Mr fourdan at the beginning of this week, he's the creator of the scoprion calculator freeware and He's testing most of the brushless that comes on the market.
I asked him lots of advice about testing motors and prop and we will soon publish the test we will make with:
pulso 2814/22
MK3538
AXI2814/22
AHM motor
APC 12x3.8
XOAR prop 2 blades and 3 blades.

I want to find the best combo for heavy lift multirotors ;)

Can't wait to see those results! My money is on 14x4 on top, 14x6 underneath - should be a good combo.

Droider
04-16-2011, 04:28 AM
This Forum is attracting innovative and forward thinking individuals who are willing to share their findings and offer words of wisdom to newcomers. Glad I stumbled across this Forum, I can think of other forums where newcomers questions are treated with disdain. I have a good feeling about the future development of this Forum ?

Sid

Aint it great... :):):)

Droider
04-16-2011, 04:29 AM
Can't wait to see those results! My money is on 14x4 on top, 14x6 underneath - should be a good combo.

Jes.. what you flying? Are you talking coaxial in quote?

RTRyder
04-21-2011, 08:47 AM
Tuesday I needed to get some still shots and since the stock Hexa hadn't fully recovered from an unintended landing event I used the Droidworx heavy lifter with my Canon SX 200 on the Pro Mini mount which is sort of like using a shotgun to kill a fly...;)

What I found when looking at the stills surprised and disappointed me, the majority were blurred from vibration which is something I've NEVER run into before when shooting stills from a multirotor. The culprit I believe to be the set of APC 12 x 3.8 props I recent put on, I was able to get great still shots when I had the Grauper 11 x 5 props on it but unfortunately Grauper doesn't yet make a 12 inch pusher prop and the 2814-22 motors on the Droidworx really need at least a 12 inch prop.

Pending the results of testing I'll be doing with the Xoar props on the stock Hexa I may consider using a properly sized set on the Droidworx though I hesitate a bit to use a wood prop on a multi with an RTF weight of over 8 pounds, or about 3.5 kilos for those of you in the metric regions of the world.

So rather than futz about for hours with a prop balancer trying to make the APC play nice I decided to take a bit of a gamble on a set of the 12 x 3.8 carbon fiber props from Simon Jardine in Australia, these are the same ones being sold by the MK shops in the US. No they're not cheap, but the total cost for a set of six is roughly comparable to what I used to pay for a set of 710mm C/F rotor blades for my gasser helis so I don't feel it's wasted $ if they do the job and are perfectly balanced as advertised.

I'll let everyone know how they work out.

Ken

jes1111
04-21-2011, 01:02 PM
Ken, sounds to me like you hit a natural resonant frequency on something near the camera. I've long wondered about "active mass dampers" on the arms - some small weight clamped to the arm so it can be slid into a "tuned" position to "catch" the vibe. On the other hand, balanced props is probably easier ;-)

Just occured to me: you didn't have AIS switched on did you?

CopterCam
04-21-2011, 07:18 PM
Ken, sounds to me like you hit a natural resonant frequency on something near the camera. I've long wondered about "active mass dampers" on the arms - some small weight clamped to the arm so it can be slid into a "tuned" position to "catch" the vibe. On the other hand, balanced props is probably easier ;-)

Just occured to me: you didn't have AIS switched on did you?

Kind of like a Wolf note on a Cello..........many quality Cellos over resonate on a particular note. usually f, f sharp or G. and it is most apparent on the G string. The fix is fit a suppressor on the G string after length(non playing side of the bridge) and tune out the offending wolf note by adjusting the position of the suppressor.

A quick fix is to crimp some light lead Fishing shot to the after length.......maybe this might work as active Mass Dampers ??

There see......I knew there was a reason for vain attempts at Cello:)

FOX222
04-21-2011, 07:29 PM
The fix is fit a suppressor on the G string

Never mind. Too easy!

Bartman
04-21-2011, 07:53 PM
There see......I knew there was a reason for vain attempts at Cello:)

yes, the bassist for your reasoning is sound

Emowillcox
05-01-2011, 11:41 PM
I want to get some props over 12 inches probably like 14 inches can someone tell me where is a good place to order?

Stacky
05-02-2011, 04:26 AM
Agree entirely, there is another forum where the childishness has got too boring.


This Forum is attracting innovative and forward thinking individuals who are willing to share their findings and offer words of wisdom to newcomers. Glad I stumbled across this Forum, I can think of other forums where newcomers questions are treated with disdain. I have a good feeling about the future development of this Forum ?

Sid

Emowillcox
05-06-2011, 05:46 AM
Hey Ken I was just wondering if you got to test those carbon props yet?
I'm still looking for a good source to get large props over 12 inches if anyone has suggestions?

Bartman
05-06-2011, 06:34 AM
Mike,
I've been using Xoar props on my Okto and I'm really happy with them. You can order them from www.bobshobbycenter.com in florida but they're special order so you have to order at least 15 of the pusher version and there's about a six week wait. 1001-copters.com may have some in stock and you can check with electricwingman.co.uk also but you're looking for a larger size so maybe, maybe not. Definitely from Bob's though if you don't mind waiting. What size are we talking about?
Bart

1001 Copters
05-06-2011, 07:57 AM
Hi,
one of my US customer pointed me that my shipping cost to US were a bit high. I watched it closely and I raised it of around 5€ (around 7.25$) because yes it was too high. It's still expensive because the shipping cost is the same for 0.2kg or 1kg but I'm doing my best to satisfy customers :)

Regarding different size props, I can place a special order for my next batch if some people are interested. Even for small quantites. I will ask for a commercial proposal to XOAR.
What I have seen about XOAR prop is that the precision pair are far better than the normal ones (not to say normal are crap ,no, but precision are beter) It's still unbalanced but the flying behavior after balancing is great (customer 's point of view).

I have launch some test one motors and propellers to see best efficiency, less vibration and best couple motor/prop and I will communicate the results on boards.
For now I have the efficiency for a few motors (AXI 2814/22, Mk 3538, pulso 2820/14, AHM 3506) but I will publish when I will have all the data.

RTRyder
05-23-2011, 12:29 PM
I've now had a chance to get some flights in on the stock Hexa with the 10 x 5 Xoar props. The biggest difference Xoar vs Graupner is the noise level, the Graupners sound like a swarm of angry bees, the Xoar have a whispering sound that is much less noticeable. Once the altitude goes above 30 feet or so its hard to even hear the props unlike the Graupners which could be heard at much higher altitudes. Balancing also seems to be very good on the Xoar, I haven't checked them on a prop balancer but I see no visible vibration in the frame while hovering nor in any of the stills or video I've taken while using then, so they're balanced at least as well as the Graupners and far better than APC.

Stiffness of both props seems to be about the same, control response doesn't differ from one to another. The Xoar may have a bit of an advantage in the amount of lift generated having a wider blade profile, they don't require quite as much throttle as the Graupner to maintain a hover and a hard push upward on the stick will send the Hexa straight up with no hesitation.

Haven't had a chance to gauge any difference in flight time and battery usage of one vs the other yet, weather has been wet and windy for the last two weeks and it appears my vacation week is going to be much of the same.

Overall I'd say the Xoar are a good choice for a stock Hexa and the reduction in the noise factor is a big plus no matter where you're flying.

Ken

Droider
05-23-2011, 02:30 PM
Ken thats very informative.. I would defo be interested in reducing noise levels. How have you got on with the carbon ones you got?

Dave

RTRyder
05-23-2011, 02:57 PM
Ken thats very informative.. I would defo be interested in reducing noise levels. How have you got on with the carbon ones you got?

Dave

The carbon fiber props are on their way back to where they came from on RMA, one out of six was close to being balanced the rest not at all. Hopefully the new set will be as advertised and fully balanced.

I did do one or two test flights with them just to see how they worked, didn't notice a lot of difference from the APC 12 x 3.8 they replaced in the limited time I had them mounted. If the timing of everything works out I should be getting the new set about the time I get the Droidworx back together, I'm trying to get all the updates done in one session so I won't need to put a wrench to it for a long time. With luck I'll have more to say about the C/F props around the middle of June.

Ken

Droider
05-23-2011, 03:49 PM
Guess the Xoer props are worth considering then.. Ill take a look in to getting some to try ready for my new build

Dave

Emowillcox
05-24-2011, 06:00 PM
Hey Ken... where did you get your APC 12x3.8 props?
Do you remember the going price?