Cavitating Cat

[rockwerks]

Hi,

appreciate all your advice, i have always had the esc set to soft start to help minimise cavitation.

Rockwerks i bought the rudder and strut combo, i didnt know that there was a distance the rudder had to be relative to the prop? I cannot adjust there distance from the transom.

I have an 1800kv motor but thought i would cavatiate more because it would be turning almost twice the speed, with a smaller prop? I am not sure how thrust works, is (small prop + high rpm) = (large prop + low rpm)?

prop design has as much to do with cavatation as anything else. a flatter pitch with more rake will give you less rooster tail and tighter thrust cone.........what combo is it?

[r1wheel]

i purchased the strut and rudder from the same place i got the hull (ebay), there is no brand on either. I have attached photo from different angles, i prop too close to rudder?

[domwilson]

I would try reducing the weight. Try a Feigo 9xl with 4s1p. 8lbs seems kind of heavy for a 29" cat. I have a 30" cat that doesn't weigh that much fully loaded.

[rockwerks]

i purchased the strut and rudder from the same place i got the hull (ebay), there is no brand on either. I have attached photo from different angles, i prop too close to rudder?

IM not the biggest expert but have read alot on the subject and believe that you have several things going on here. one is the strut is sitting about 1/4" too high or more. running the prop wetter will give you less cavatation and higher speeds...within reason

as for rudder orientation it appears not too close but too far back, (maybe off base here anyone else?)

this is what I was reading along with many other sites:

http://rcprops.com/TechNotes/rcprop_tech_info.htm

[eboat]

I do not think you need to run an 8S setup but I think you need a larger prop

I run a KB 10XL (1200 KV) on 6S and the same 200 amp esc in a 36" hydro and had alot of trouble with cavitation untill I started to get a bigger prop

I am now up to a X450/3 and it jumps up on plane as soon as you start
My average amp draw is a little less than 90 amps (kept track of time and how much to recharge) at just over 53MPH

If you have a smaller boat and a smaller prop and lower rpm something is drawing too much amps ( but this is a cat vs hydro and how much differance that makes?)

[domwilson]

Take a look at this thread. The Skunkworks cat looks similar.

http://forums.offshoreelectrics.com/...ght=skunkworks