Prop for Smash Shark and Leopard 4074 2200kv?

[Dashunde]

I'm about done building my new Smash Shark and its time finalize my OSE order for the last bits and pieces, unfortunately there isn't a whole lot of info out there on this boat.
Its 4s 5000's 50c thru a Sea King 180a.

I need a good prop. I read somewhere this hull works well with a 3-blade, but I don't know the specifics?
I dont want it running hot or short run times, this is a basher for around the dock, but I don't want to give up a bunch of top end either.

Also need..
Longer rudder (that either mounts to existing TFL bracket, or at least uses the same holes + a couple new holes if needed?)
One-piece cable/shaft
Larger turn fins
Trim tabs

I'm not overly familiar with boats (particularly what size of things I should buy) and most of the info I've found on alternative parts for this boat refer back to HKing and its old or out of stock... and I'd much rather buy from OSE anyway.

What would you add to it?

[MarkF]

I wouldn't upgrade anything until you decide it needs it. The one piece cable is a good idea but I don't know you need anything else until you run the boat. That motor combo works great on an Octura 447 prop for racing. A 3 blade pulls the corners harder for racing but eats up run time. Stick with a 2 blade. If you want more runtime you need to run a 445 or 442 prop.

Mark

[Rc4me]

I orded a dual rudder for mine from ose
Part number ose-83252 i just use one side of the bracket. Best upgrade i did to it. It turns so much better.
20170727_185034.jpg
I also installed one piece driveline...and the trim tabs...running 6s 1450kv 4082 turning a 44x1.6 temps are 117 basically around.

[Dashunde]

Ok, ran the boat on the stock 38mm prop with decent maiden results overall... by that I mean everything worked, nothing went wrong, it didn't leak from bolts or seals, and it moved out pretty well and didn't exhibit any really obnoxious behaviours.

Straights/speed
Nearing full speed on a somewhat small'ish pond the bow wont stay down, but it runs straight and doesn't lean.
Cog is at 10.5" from transom, 32" total to nose. (~32%)
Stinger is dead level with keel.

Turns:
Wallows/rocks a lot in the turns in mild chop (conditions similar to race course, our cove or pond with mild winds)
Spun out a time or two.
Turns left fairly well at speed.
Almost entirely refuses to turn left at slow speed (problematic when maneuvering around dock(s)
Stock turn fins are trailing at 45deg - should they be straight vertical?
A larger rudder is obvious and on my list, will that help correct the wallowing or is that something else?

Prop
Sorely needs a bigger prop
Lots of cavitation
All temps were barely warm and I got ~10 minutes of goofing around in the small'ish pond on new pair of GensAce 2s 5000's (20% remained when charged)

I have no idea which prop to get, or even what type.. X, M, or 3-blade.
I'll mostly run this thing in tighter areas, smaller ponds and in our cove amongst the docks.
A quick hole-shot and tight mid-speed handling is more important that pure top speed, further backed up by its tendency for bow rise at speed anyway.

Thoughts?

ps.. I do have a unusual amount of water backing up the tube between the cable and teflon when its sitting still, and it pumped plenty of grease out between the hull and stinger.
Is that normal or do I have a fit problem back there? None of my smaller boats do this..
On my smaller boats I've been using the generic blue "marine" grease from Walmart that I use on my real boats and trailer bearings, etc.

[MarkF]

If you're running a 38mm prop then a X 440 3 blade would be the next size up and give you more hole shot. But you will shorten runtime 2 or 3 minutes. Most don't get more than 4 or 5 minutes on there boats.
Put the turn fins straight down. If you're spinning out and wallowing this will help. Your cog is too far back if bow won't stay down.

Mark

[785boats]

Rob.
As mark stated, an Octura 440/3 is a good prop. I sort of half de tongue mine which still retains the torque & allows toe motor to rev out a bit more at full throttle.
Too large of a diameter prop on these slender hulls can induce excessive torque roll. I've also had good success with a CNC 4214/3 with your setup & boat size.
We found that a larger rudder certainly made a big difference in the turns with the Smash Shark.

The gap between the transom & the stinger can be sealed with some silicone sealer.

About 1 degree of negative angle on the stinger will help keep the nose down.

[Dashunde]

Thanks all.
What is the correct 1-piece cable from OSE? There are a couple 3/16 to pick from..
Long shaft or shorter shaft then there is this one for the Voracity with similar dimensions.

The stock shaft is ~3.00 inches overall including the square drive part, the bushing contact area/drive dog/plus prop/nut is about 2.25".

BUT... here is a oddity maybe you folks with much more experience can clear up.. The stock shaft measures 0.184" and its cable is ~.185" and it does NOT fit through the stinger bushing.
So... how are any of these 3/16 (.187") 1-piece assembly's supposed to fit through a ~.185" stinger bushing?

[a428q]

Had same problem. Cordless drill end sandpaper worked. Shaft in the drill sand and polish until you happy with result.

Sent from my SM-G920T using Tapatalk

[Rc4me]

I bought an ose 18in and cut to fit. I didnt have that issue. The flex was tight going in but after the first run it was fine. Im assuming it wore itself in.

[Dashunde]

Well... I bought a 440/3, put a bunch of work into it, and it ran great.. until that damn grub screw bullet that holds the prop onto the unthreaded shaft let my new prop fall 30ft to the bottom of our cove (murky, no hope). Apparently I didnt get the grub straight and tight. :/

So no matter what it takes.. its getting a one-piece ose shaft along with another 440/3.

I'm considering replacing the stock tfl stinger bushing along with the shaft for a better shaft/bushing fit without any sanding & polishing to make it fit the odd undersized stock bushing.
Anyone have a clue what the OD is on a stock TFL 3/16 stinger bushing? I'd rather sand the outside of the bushing to fit the stinger instead of sanding the new shaft and cable to fit the stock bushing.

[CraigP]

I use Locktite a Blue on all those grub screws. I also use it on the drive dog to the prop shaft. Locktite your shaft saver collar too if your using one

[rol243]

the use of Locktite is a must for any motorized craft.

[785boats]

Sorry to hear about your loss of prop.
The "Pond Gods" have stolen many of my props & shafts too over the years.
I'm glad you like the way the prop works on that set up.

[rol243]

its not a bad idea to use a small collet on the shaft as a shaft / prop saver.

[Dashunde]

So you know how some boats are just evil or doomed right? I got another 440/3 prop on it, ran it at the lake and it ran really good.. into a dock :/
I promptly ordered a new Smash Shark - cause I had it running good, the second one was $30 cheaper than the first, and I have all the upgrade parts for it already - the new one showed up today and I got all the good stuff swapped into the new hull, including marking/drilling the OSE 4-bolt rudder, in just a few hours.
This boat is already much more cooperative :)

I like the 3-blade, but its making my ESC wires pretty hot, I should probably go with bullet connectors but I use all of my 2s hard packs in my 1/8 scale buggies/trucks too, so I want to stick with the Deans.
What would be a step down from a 440/3? 440/2? Maybe a 442? or just detongue this 440/3 some more?

[rol243]

you could take some diameter off the 440 x 3 blade to bring it to around the 435 mark ; 40 mm down to 35 mm. as previously mentioned the 440 x 3 blade is a better prop for faster turns but in the straights it will eat up battery power , this could be why your wires are getting hot. if you want to try a 2 blade try something like a 447 and you can cut it down to a 445 size than maybe a 442 size ,if needed. to find the right prop you need to play with them.

[iop65]

The wires are getting hot because those deans are getting hot.
A 35mm prop is too small for a boat this size.

[Mxkid261]

I agree the dean's are probably not a good idea I would run at least a 5.5mm bullet.

[MarkF]

Take the tongue off. The tongue helps the boat get out of the hole from a dead stop but also helps torque the boat over and acts like a governor for speed. We don't need tongues any more with the amount of power we have. If your wires are getting hot then the deans plug is too small or you're running your boat to long.

Mark

[Dashunde]

Alrighty.. the wires were hot on the first boat with the 440/3 and trim tabs installed, it ran much wetter and slower with the tabs mounted ~1mm up and flat/parallel with the bottom.

On the second boat/rebuild I left the tabs off and only installed the much larger ose rudder (which works great and fits perfectly btw)
Its definitely faster, runs longer and it comes back warm but not super hot.. the trade off is its also pretty rowdy at speed (chine walk) without the tabs.
Next I'll try getting some weight in the nose instead of adding drag to the back.

Aside from that this hull seems naturally ill suited for pure speed (like the Outerlimits) or speed and good turning (like the Pursuit).

Perhaps its a better rough water all-purpose fun boat... so with that in mind I'm going to try a slow speed big wave setup to run alongside our full-size boats.
~20-25mph on 2s (2x 2s 5000's in parallel for really long run times)
Nearly zero cavitation out of the hole, looking for really good throttle response/hookup at slow speed.
What would be a good prop for that? Maybe something like a full-tongued x452/3 or 455/3?

I realize it will torque roll more, but not really worried too much about it due to going slow'ish, so long as it doesn't just lay over on it side and stay there.

[Hydrocarbon82]

If you have split tabs like the Pursuit, set the outer tabs lower. That will lift the rear in a turn, pressing the nose in a little for more bite. Give the strut more angle if it runs wet with tabs installed. My Pursuit has the tabs all the way up with a decent angle added to the stinger. My tabs came bent with 1-2 degrees which puts their tips ~1mm below the hull edge, but I've considered bending them flat.

From what I've read, the Pursuit runs circles around the SS and OL hulls. Your hull is 20mm longer but 20mm narrower, which will make it less stable at speed...but potentially faster if that 20mm adds to the lower transom. The Pursuit is down to $160 atm, I'm almost considering a 2nd. It uses all the same internal parts and the stinger is 78mm, so you may be able to swap all the parts if you change hulls.

I also would be careful if your "big wave" setup intends to actually create a large wake by not getting fully on-plane. Planing hulls like this require a lot more power before they get on-plane. Buzzing around at half throttle with a few full throttle stabs will use less juice than constant start/stop.