Letter Designators for Prop sizes

[peells]

Hi there,
As I am rather new to the sport I was wondering what the Letters stand for on the propeller packages? example; X438 ( I have this prop) but have no Idea what the letter means. I have also seen Y and I am not sure what others are out there, if you all do not mind please give me a clue, but my all time favorite just tell me.

Thanks,
Pete

[robby76]

go to page 3 of this main forum thread and look for the topic of different in x & y props. this link might get you there;
http://forums.offshoreelectrics.com/...read.php?t=573

[ReddyWatts]

Different types of Octura props

12 are low lift ideal for submerged drive
X4 are medium lift general purpose props
M4 are like X4 but with the tongues removed to unload the prop
Y are like X series but have 10% more pitch
X5 are general all purpose med lift prop
X6 are higher lift than X4 and suitable for surface/semi surface use
14 are moderatley high lift for hydros and deep V's
16 are high lift props for riggers and hydro's
17 are the highest lift prop for riggers and outboards
P7 are similar to 17 series but more rake and less lifti
19 are high lift for riggers and hydro's
V9 are moderate lift suitable for riggers, hydros and SAW racing
20 are moderatley high lift suitable for riggers
21 are high lift for riggers and hydro's 22 are high lift surface drive only good straight line speed

[NativePaul]

There is one that I don't know, I just saw one an Octura N series for the first time on OSE and ordered it so I guess I will find out what its like soon enough, but does anyone know what a N series prop is like? From the picture it looks like it could be related to the M series like the Y is to the X, ie a little more pitch, but the looks of a 1 dimentional picture can be deceiving, and it also looks quite similar to a 19 series.

[peells]

Reedy- thank you for the information it is really helpfull not only for my self but for other nubies like my self.

[peells]

Prop sizes

OK now that I am armed with your custom prop sizing chart here is what I have...
a 28 1/2 inch mono with a 8 1/2 inch beam, I am running a x438 metal prop and 6s lipo so far I have only been able to open it up half way and it does an honest 40-45 mph, I tried the next 3 sizes up but my boat would do 360 degree cork screws do you have any other recommendations?

[OBX OSE]

Too much prop mabye, when you stepped up the prop diameter.To much prop=to much grip and will try to turn the boat insted of the prop.You could also try spin fins which will keep the boat from spinning out.When you said you tried the next 3 sizes up do you mean x438 to x4

[OBX OSE]

My cat ended my post early.lol If you increased your prop size from a x438 (38mm dia. 2.100in of pitch) to a x445 (45mm dia. 2.487in of pitch) the prop might be too big.

[peells]

prop sizes

Sorry about your cat... but I did go back to the x438 and it did calm down the cork screw affect and since then I fried my motor bench testing my system so... I need a new motor I am thinking about getting a KB45xl 1700kva to try and slow down on the revs a little from what I have now. Then maybe I will be able to get full throttle and about 50+ out of it.
I had done some serious mods to motor position stuffing tube location and battery tray location for the 30% C.G. my stuffing tube was under the boat and at the speeds this thing was running I think with the stuffing tube under the boat it was causing a hydrofoil effect and not to mention some added drag because the boat was rocking from side to side at high speed. and as luck would have it after making the changes the motor fries before I could test it (rats)

Thank you for your help,
Pete

[OBX OSE]

Sorry to hear about your motor, do you know why the motor fried is it water cooled?What boat do you have?I took a 1 1/2 ft piece of fuel/water cooling tubing and took off the spray nozzle on my kitchen sink hose.I then had to slightly drill the hole out where the nozzle connects to the hose on the sink.All i did next was push the fuel hose into the larger hole in the sink nozzle hook it up to the boat turn the water on low.Now when i want to bench test i can cool my motor with the faucet water pressure it works great.Just an idea if the motor over heated when testing out of the water.:) When you say your stuffing tube was under your boat do you mean on the very bottom (outside the hull).If the suffing tube was on the outside of the boat that would defenitly cause a stability problem.Good luck man!

[peells]

Nice idea about the kitchen sink but my wife would have my head I up graded it a couple years ago with an expensive faucet! but it may be worth considering for my garage sink thanks for the idea. But as far as the motor goes it should not have burned up for the few seconds I ran it. Some time ago I hit a rock when I lost control (stupid glitches) and it bent the motor shaft slightly. I just noticed this a week ago before it burnt up I tried to straighten it but no such luck.
My boat is a home built from scratch no kit I drew the plans and made it. I had great fun making it, my oldest son and I were building boats at the same time and were having a great time of son and Dad time I would not trade that for anything.
And I did have the stuffing tube out the bottom in the keel about three inches back from the transom (but not any more that is one of the mods I made)

Pete

[Bill-SOCAL]

I use an old glow fuel hand crank pump to check cooling systems. Just connect it to the end of the rudder end of the tubing and hang the pick up from the pump in a container of water. You can do it outside and generate WAY more pressure than your cooling system will ever see. I can shoot the water several feet out of the exit point.

http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXJGS5&P=ML

http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXMA93&P=ML