rigger help

[elijah]

I took the plans from the Predater outrigger and enlarged them and made it out of balsa covered with a thin coat of fiberglass cloth and resin it came out very durable and light it is 32'' long and 19'' from out side to out side on the sponsons redy to run with out the batt. it weighs 4.2 lb. I am runing the ul1 motor and esc my batt. is the turnigy 5.0 40-50c brick it weighs 20.6 oz I am runing the octura m447 and am runing in the high 50s low 60s but after the five laps we run in the race in our club the caps and the back of the motor get blistering hot I am not getting a smocking genie at all but I am woryed about burning the motor or esc out I think I need to go to a smoller prop but cant figure out whitch one to go with wanting to keep as mutch of my speed as posable but loose the heat can any one help.

[NativePaul]

You can probably mod your existing prop and lower the temps a bit, over here we race hydros for 5 minutes not 5 laps, worthwhile increases in runtime (due to lower average amp draw (which is good for temps)) can be had by modding the prop you have rather than propping down, I'm not a big fan of the Mseries of props they do work but the blades tend to be thicker than X series, which puts more load on (if you de-tongue an Xseries to Mseries shape the X will give you more runtime and less prop walk) if you havent already thin the blades down. On most boats the tongue can be cut back further than Mseries with no ill effects most of my boats wont take a full bore start leaping out of the water if they get one so a slight degredation in the hole shot is no disadvantage. you can also backcut the trailing edge, by fileing it down at an angle so its stock at the tip but 2-3mm down at the hub, this does have the side effect of reducing lift a touch so you may have to nudge the CoG forward or put a hair of down trim on the strut. All 3 together will lower the amp draw significantly and as you have lowered the blade area but not the pitch, if the lowered amp draw allows the motor to unload and spin faster you may well see a higher speed than before.

[martin]

Nativepaul have you compared the Etti props with Octura X series as the Etti is much reduced in blade area for a comparable size prop especially in the tongue area. Im still waiting for very flat water at the moment before running the Etti props to get a comparison. Martin.

[NativePaul]

I have seen them at races and they look better in the flesh than they do in pics but have not compared one side by side with an Octura or run one myself. From my brief gander they look like they have more in common with Graupner carbons than Octura, having low blade area and very low lift, I didn't really pay a whole lot of attention to them as I'm cheap and it's a lot of money to pay for an aluminium prop, though I don't like cutting props at all id rather put half a day into cutting one than pay three times as much for one that doesn't need cutting, if they milled them from stainless that wont break if it hits a twig instead of alloy I'd probably change my mind as that's a full day of hand aching graft for me, but I know a guy that has bought them, liked them, broken them, and gone back to carbon saying there just as strong but cheaper.

[martin]

On something like an Octura x435 that im using at the moment if its detongued does it increase top end a bit & decrease excelleration some. Martin.

[NativePaul]

On an X series the tongue is lower pitch than the rest of the blade, it helps reduce cavitation when stationary but once your moving at a reasonable speed its backpedaling and fighting against the higher pitch areas of the blade.
You should get better top end and better mid to high speed acceleration from taking the tongue off an X series prop.

[elijah]

I thank you fore you knolidg but I am a newbe only ben boating a cople of months I don't rill understand everything you are trying to tell me is it posable fore you to dumb it down a little so I can make sence of it all thanks again. Eli