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boredom.is.me
04-30-2016, 11:48 PM
Hey guys,

I'm kinda looking for some help on where to get some props from. There are a million threads on my setup or similar so I have made a decision.

Daytona 37" Cat
Leo 4082 1600kv
6s 5400mAh
180A Turnigy Marine (the older version)

ALL PROPS BEING DISCUSSED ARE CNC BASED PROPS. Due to possible running conditions, I'm not interested in $50 props. (I do have for my smaller hydro though. :) )

I have tested this with an X442 as that's all I had from my smaller boat. I want to move up to an M645, but can't seem to find one. I'd even take an M445 or M545. Kintec has an M744 and an M745. OSE has an X945. Both shops have the standard X445. The X945 is way more than I want to put on my system, and I'm honestly trying to get away from the X props.

Any recommendations? I've been out of it for a while and have noticed a few shops have closed down.

Thanks,
Kev

785boats
05-01-2016, 12:49 AM
RC Boat bitz sell a large range of cnc props. Here's the one you are looking for.
http://www.rcboatbitz.com/index.php?main_page=product_info&cPath=48_67&products_id=2382

boredom.is.me
05-01-2016, 02:15 AM
That would indeed work. The downside is that it would be coming from down under and I'm in the US. I also wanted a new 42mm prop. I'll probably just compromise on the 45 and grab the X445 and M642 from Kintec.

Fluid
05-01-2016, 09:14 AM
I am puzzled, why use tiny 42mm props on a 37" cat? Prop efficiency will be poor as will speed compared to what a larger prop would provide on that easy-to-push hull. That setup should be able to turn at least an x447 or x648 with the T180. A better ESC would allow an even larger prop. Just a thought.



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boredom.is.me
05-01-2016, 11:38 AM
With that said, do you think the M745 would be fine?
The 42 is for my 26" hydro.

Fluid
05-01-2016, 12:10 PM
I don't know what an M745 is. IMO a 45mm prop is just too small for that big boat. A CNC 4814 would be worth a try. IMO the motor Kv is probably too high - but that is what you have.

What prop is safe to run can also depend on boat setup. A wet running boat will pull a lot of amps, loosening it up will increase speed and drop amps. How you drive effects this too, too much on/off the throttle can cause excess heating that a more constant throttle use would not. Driveline alignment and strut/drive dog gap are also players. Then there is battery capacity and discharge rating, too little of either and the boat may not plane out well. It is a system, not just the prop.


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kfxguy
05-01-2016, 12:32 PM
I am puzzled, why use tiny 42mm props on a 37" cat? Prop efficiency will be poor as will speed compared to what a larger prop would provide on that easy-to-push hull. That setup should be able to turn at least an x447 or x648 with the T180. A better ESC would allow an even larger prop. Just a thought.



.

Part of the reason a 45mm or less works well on this boat is because it's very narrow. It has a lot of torque roll with bigger props. The x648 I had on it did not drive well at all (it wanted to roll badly) but when I put a 645 on it, it was much better. Just my experience I'm speaking from.



Also....say we were talking about a hull like my shocker (37" but a good bit wider) I'd say definitely run a 48-50mm prop. I run a 48m prop on my shocker. But was running a m645 on my Daytona. Went like 87-88mph. For straight up speed runs, you could use a 48mm. A guy I know, I setup his Genesis and with a 48mm abc is runs 103mph but I don't think the op is looking for that. Lol

Fluid
05-01-2016, 01:48 PM
The torque roll can be fixed by offsetting the drive to the right and the packs to the left - I did this on two narrow cats but then neither of them was a Daytona. All it takes is an analysis of the most efficient drive system, what the cause of torque roll is, and what can be done to eliminate it.

But of course if the OP just wants a clone of so many other cookie cutter narrow cats, then I guess he can use little props too. :noidea:


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boredom.is.me
05-01-2016, 02:20 PM
Here is my cookie cutter build. It's not much to show, but then again, I wasn't trying to impress anyone. This was just a fun, simple and straightforward build for someone else. I have a second hull that I may build as a twin.
http://forums.offshoreelectrics.com/showthread.php?46172-Kev-s-Daytona-37&p=562051&highlight=#post562051

M and X are prop types. M does not have the tongues while X does.

Either way, thanks everyone. I made my decision and I'll let you know how it runs.

dasboata
05-02-2016, 09:56 PM
I have the m 645 in stock PM me if interested the 600 series are fast A$$ PROPS !

boredom.is.me
05-05-2016, 09:14 PM
I missed your post, but I definitely know where I can find a pro prop magician. :thumbup1:

boredom.is.me
05-08-2016, 07:14 PM
My choice was an M642 and an M745. It's blazing fast on the 42 and came in cold to the touch. I didn't really get to play with the 45 as I dropped the allen key off of the dock. The prop was running way too deep.