Propeller Scimitar for the Tiger Neptune

[deepseadiver]

Hi i wanted to know if anyone can tell me how does the Scimitar Propeller work on the Tiger Neptune compared to its original metal propeller, plus if any one has used it on any other type of submarine.

Thanks Jim

[deepseadiver]

here is some good in formation i found which i think will help me and others

A chap runs a Neptune with the 6-blade scimitar prop at some events I organise. It offers a modest improvement in performance over the stock prop, but the boat is still a bit of a slow coach.

The best type of prop for this boat would be 'kort' nozzle type prop, as the Neptune is fitted with a shroud. I would think a 35mm-40mm three or four blade prop would suffice.

Raboesch and Prop Shop both make good kort style propellers, and they're made in metal.

[deepseadiver]

I got a new propeller yahoo it works much better im a happy camper its the speed boat i always wanted not just kidding but it's faster and turns better enough power, if i wanted to put bigger front planes on but i wont. I think it tuns just fine with the original ones on changing them out i think is over kill even if you want a serious under water explorer hint hint LOL ? I think it's just about perfect right out of the box so buy one from Caswell he backs up his products know that's what matters and they have a good engineer behind the whole thing to answer technical questions David M
jim

[He Who Shall Not Be Named]

Below cavitation RPM's, the only blade geometry that matters is total projected blade area and pitch. You're not worried about audible 'thumps' produced by blade travel through turbulent flow, so skewed blades for us (hobby guys) is just for 'looks'.

Don't over-think this.

David

[deepseadiver]

so David the reason im getting more power speed out of my new prop not much more but enough so see a difference it's because it has more projected blade area and pitch am i correct or off track insure me please. ?

Hi David your QUOTE: the only blade geometry that matters is total projected blade area and pitch

[He Who Shall Not Be Named]

likely because it has less area and/or less pitch than the origional.

[Subculture]

The 4-blade prop you have fitted now has about as much blade area and pitch as you can get, judging by the photo in another thread. If you want more speed, then the only route now is a more powerful motor.

[deepseadiver]

Hi Subculture,

I dont need anymore speed other wise it starts crusing like a speed boat. I have seen now a good deal more speed by going from the orignal 3 blade prop to a 4 blade and im happy with the results, I will show a video soon. Now i can shoot across the pool pretty fast if i want to also turn's more shiftly . The new conning tower, sail that is what ever way people call it. Makes a nice wake going behind the boat like a real sub now . Compared to that original clear plastic dome it comes with did nothing.

Jim

[Subculture]

That wake is drag. The clear dome presents minimal drag as it's teardrop shaped, but it looks a bit naff. To get the boat turning really well, you could modify the fixed nozzle to a steerable one, with the rudder fixed to the nozzle.

[deepseadiver]

hay thats a great idea i will look into that, with the prop nozzel becoming a steerable nozzel . The word wake i was wondering what they called it correctly its Drag . for some reason i like the effect very much
thanks for the tips
Jim :)

[Reckless]

that extra drag of the new tower/sail you added will assist your steering too .. the extra drag will create sort of a braking pivot point ... same effect probably changed the way it reacts to surfacing movement of the planes, and makes diving a touch harder (the drag will make it want to nose up a little more then stock) ...