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View Full Version : What's a better prop for sport running?



wparsons
06-18-2011, 09:59 AM
I've read good things about the grim 42x55, the octura x442 and m445, with the best reliable speeds seeming to come from the m445.

I'm not racing it, so I don't need 4 minutes of WOT good power but I also don't want a setup that is only good for a couple SAW passes.

Stock motor/esc, 40c 5000mah 2s packs in series, so heat is the only concern. It came in barely above ambient temperatures this morning on the maiden run with the stock prop, so I've got a lot of breathing room.

Fluid
06-18-2011, 07:09 PM
A metal prop is a natural upgrade, but which one? I tried the AQUB9725 42X55 2-Bladed Prop and the M445. The latter was faster but the former was still very good. You will probably have to change the strut setting or CG with a different prop. I like the m445 best and got good run time, but it will depend on what you really want, the temperature of the water and what you really want.


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wparsons
06-18-2011, 09:03 PM
Were you running it on 1p or 2p? I think I'm convinced on the m445, seems to be the super prop for all boats lately :p

jeepme
06-20-2011, 10:51 AM
I am very happy with my Grim 42x55 for sport running. I am getting good run times, good speed, and heat is good also. Still trying to find the sweet spot for battery placement though.

Stinger9D9
06-25-2011, 06:08 PM
I managed to pick up an x445 at a new LHS I found out about today, which was a major score as finding any type of prop locally is pretty tough around the GTA. It was the 2nd store I tried. The first one had either everything that was way too small, or way too big.

When I was at the store and saw the x445 - and remembered that the M series is basically a detongued X series, I figured I could just detongue the prop while sharpening it anyway.

I ran a detongued x642 today on my cheapo interim Turnigy 1800kv motor (a proper AQ motor is on the way), and the X642, though larger than the stock prop, ran cooler. Maybe because it was so sharp (the stock plastic prop is pretty dull and probably has a fair amount of drag).

Oh yeah, I also picked up a couple Octura plastic 1445 props for a couple bucks a piece. They are the same diameter and pitch as the m445 and they look to be slightly detongued too:

http://www.funrcboats.com/ProductInfo.aspx?productid=OC1445PL

Of course they would flex more than a metal prop, but for the price they'll be worth a shot - no sharpening or balancing on them either.

wparsons
06-25-2011, 09:35 PM
What store did you find that carries props?? I haven't found anywhere in the GTA that carries anything beyond the stock RTR props.

PS - I'm the guy that was at Humber Bay today with the other Motley Crew, nice meeting you! I've got pictures and video coming soon.

Stinger9D9
06-25-2011, 10:39 PM
The store is up in Woodbridge:

http://www.rcsports.ca
They have a pretty good selection of props (but unfortunately no x642, m445 or x440/3 blades). They do have a good selection of Grimracer props though.
Oh yeah, they also had a Motley Crew on the shelf! I couldn't believe that!

The other shop I went to that had quite a few props (just none of the Octura props that I needed) is:

http://www.johnshobbies.ca/main/
They do have quite a few Aquacraft too and the shop is just down on the Danforth.

Yeah, it was nice to meet a few local guys running electric hulls just for fun - I'm not really into the racing side of it. That being said, the racing guys I have met (Metro Marine Modelers - now some of which are with the Northern Lights Model Boat Club) are all great as well. Like I said, I'm just not a racer.

I may put one of those 1445 props on the boat and the blue SV motor back in the MC for a run at one of the ponds I use in Brampton tomorrow. The Turnigy was just running WAY too hot today.

wparsons
06-25-2011, 11:01 PM
What ponds in brampton? I work in the north end of Mississauga (Derry/Hurontario). There's a pond right behind our office that I've run in a few times, and I've found a few others on google maps as well.

I wouldn't mind finding a pond with some buoys in it, but I'm not into actual racing at this point.

GP73
06-25-2011, 11:06 PM
Hey guys, great to see you at the pond today!

Make sure to come down again, we don't race, just have fun and break some stuff in the process... :biggrin:

Nice meeting you! :beerchug:

Stinger: we might be able to get RC sports to order more props for us if there is enough demand, I was trying to talk the owner into doing some prop work for me last year and then the winter arrived...

Barbossa
07-03-2011, 08:07 PM
This weekend I tried the M445 prop on the stock ESC, stock motor and 4S; it was very good. The speed was 45.2mph, the temps we all under 100degF, the takeoff was good also. I could maybe adjust the CoG and get a little better, but for now I am happy with the speed, the temps and handling. It was damn good fun!

wparsons
07-03-2011, 08:16 PM
Excellent, can't wait for my m445 to show up!

bruce5385
07-23-2011, 08:49 PM
what was your strut depth/battery placement when you ran the m445 and got 45mph. i ran that prop and ony got 40mph. has anyone ran the m545?

Barbossa
07-25-2011, 09:51 AM
There is another Motley Crew thread called “What strut depth would be best to get the nose up”. In this Grimracer wrote –

“I run mine with the bottom of the strut touching the table with the sponson on the table.
Make sure you pull up the water PU (and put it back down) when adjusting this way.
I also have my strut set FLAT on the table.

Then my favorite props
Stock, 42x55, L45x66

Batteries in the center of the velcro.

Hope this helps, Grim”

I set mine up like this also. It was going fast but a little loose. I did have a blow over so I dropped strut by about 1/8” to hold the nose down, this was a bit better.

The M445 prop does make everything run hotter than the stock prop, but just keep this in mind and do not go full throttle all the time, spend some time cursing at half throttle to cool things down a bit too.

Stinger9D9
07-29-2011, 05:43 PM
The M445 prop does make everything run hotter than the stock prop, but just keep this in mind and do not go full throttle all the time, spend some time cursing at half throttle to cool things down a bit too.

That may cool the motor down, but it could overheat your ESC. Brushless ESCs are meant to run wide open with all the power going straight through, otherwise they get hot scrubbing off excess voltage while running at part throttle. Be careful with extended part throttle running.

Fluid
07-29-2011, 06:48 PM
Stinger is right, however the better solution if you want the speed of the m445 is to limit your run time. But how hot is too hot? All serious FE boaters need a temp gauge of some kind to measure their motor, ESC and packs after a run. Maximum temp for good LiPos is 135-140*F, and 140-150*F for the motor and ESC. This is taken immediately after a run, within a minute of bringing the boat to shore. Measure the ESC on the caps and the board, and the motor on the endbell. 100*F is not "hot" at all. Heck, this time of year the motor, pack and ESC are 105*F when they leave the beach....


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Stinger9D9
08-01-2011, 10:24 PM
So far the props I have tried on the Motley Crew are the stock prop (of course), a detongued x642, a Grimracer 40x52/3, m445, Grimracer 42x55, Prather 220 and OSE Glass filled 45mm.

The m445 was probably the fastest - because when I ran the x642 I was running a blue can (about 1600kv) Supervee (waiting for a stock motor replacement). Considering how warm stuff runs (on the actual 1800kv stock motor) with the m445 I think the x642 may really ratchet the temps up there.

I like the 40x52/3, it just seems smooth and nice in the turns, but it's not that fast.

I was running the 42x55 today quite a bit, the boat looked pretty buttoned down, but I did have a blowover (caught a crosswind) so it must have been hauling pretty well. Everything kept nice and cool with that prop though, with an outside temp of 94F, the motor didn't even hit 120F. With the amount of wind today, the m445 would not have been usable.

Then I tried the Prather 220. It reminded me alot of how it ran on the SV. Nice and quick, while seemingly keeping the front end down. Once you really laid into it though, it still got up enough speed to really pick the nose up.

So far I guess (because I haven't tried the x642 with the stock motor) the m445 is plenty of prop. I really like the 42x55 though - I also like how cool everything runs with it.

jeepme
08-03-2011, 01:14 PM
Stinger are you still running the stock strut depth?? I raised my strut a bit with the M445 and it cut my temps down a bit and the speed was still better than the 42x55. Motor was 115* speed control 113* and packs where 125-130*. The only thying that really gets warm are my EC5 plugs, they are 150-155* I ve never seen anyone post plug temps so I dont know if thats good or not. Anyone know what exceptable plug temps are???

babflyer
09-04-2011, 10:15 PM
thats sad to hear as I just invested in a bunch of ec5 plugs. I have been haveing deans and traxxas plugs get so hot they desolder. The plugs are always the warmest stuff in the boat after a run. It was my first time trying out traxxas plugs. I hate them and think they difficult to solder, I think they would be nearly impossilbe for a new rc'er and pluging them in is down right dangerous. I kept imagining what would happen if I sliped trying to press the tabs into their receptacles.

babflyer
09-05-2011, 12:48 PM
i liked the ec5 plugs, they get my vote over deans and deffinatley over traxxas

jeepme
09-05-2011, 02:01 PM
i figured out my heat problem with the plugs. My battery wires are 12awg and the ESC battery leads are 14awg. I changed out the ESC to a seaking 120 which has 12awg wire and less internal resistance and now my temps are much cooler.