That sound better with a 5 mm shaft. But still be sure to support the shaft under the boat and if possible also under the shaft inside the boat. This way you shouldn't have any trouble with vibration though the shaft to loosen it.
It's nice and fast but doesn't seem to want to turn very well. What is the rudder like is it too big and also how much leading edge has the rudder got. I used to have this sort of trouble and went for a slightly smaller rudder and cut away the leading edge and it solved my problems.
When you say leaks from the jet drive, is it not seal able yourself. I know you shouldn't need to being a new boat but is it just a bad seal that can be rectified with sealant ? I like the look of the boat it rides the water well at speed. But it does seem to sit very low in the water at slow speeds.
I was also told about cutting away the front edge for the same reason, digging in on turn's. I have found on hulls like the Vosper RAF Crash Tenders and MTB hulls they sit on the water on a turn as if they are stuck on the water no roll at all. Also on the Huntsman style hull they also turn a lot better with minimal roll. It was told to me on her the other day that the rudders were meant to be the way they are and there was no need to cut away the leading edge. I have done this for many years now, since the mid 70's and had great results I even put a 10cc engine in a hull rated for 5 to 7.5cc and it was an amazing boat to run. I turned a couple of boats upside down until the rudders were trimmed and then good to turn. I'm glad I have found someone that thinks it's alright to do. 👍😊
you could use a dremel and grind some away. I have used the brute force and Tapped the shaft inwards if a few taps aren't enough then a couple of harder whacks should do the trick to loosen it. then pull it out from under the boat. It has always worked for me.
Great bit of information , Many thanks pmdevlin. I have only ever used 5mm shaft's and gone out with a variation of small to medium nylon prop's and played on the pond bank with them until I got one suitable. Then I would go for a cast alloy or bronze to that size. But this has been on IC engines, up until about 3 years ago. I have used the same way on brushless since. I have seen others using thinner 4 mm shafts and having problems. I have also always used a prop shaft support under the boat and if I have any type of gap between the coupling and where the shaft goes through the hull I would always add a wedge of wood epoxied in. Once again no backlash on the shaft to make it come loose. The only time I have damaged shafts has been through sheer stupidity racing round a pond with others and misjudging the distance and the bank jumps out and collides with the boat. Whoops broadsides with a nice hard concrete bank and, Yep new shaft needed. But as you say the throttle stick will take you from as slow as you want to flat out. Except when it's IC slow isn't always possible if you do not have a clutch fitted.
Personally I wouldn't say you were nut's. It's people like me that are probably the nutty ones. Without your help some of us would be left in the dark with some of these small motor's. I do not understand how to work out the electrics. So your help that you give is a great thing for numpties like me. To buy a IC engine and stick in a boat was an easy task. But Brushless i'm lost. So many places have banned IC's we have to now rethink. Keep you help coming PLEASE.
Thank's RNinMunich, Dave M, canabus, reilly4. for the information you have added in your post's. That will be very helpful for me with a couple of boats I am hoping to get set up in the future with brushless motors. An Aeorokits Sea Commander, Sea Queen and an MFA Spearfish.
I always use as smaller rudder as I can get away with. I had been running model boats for many years then one day when on Blackheath pond someone was watching my boat and remarked on how it turned. badly, and I replied that's how it had always turned. The guy had a boat the same as mine it was a MFA Spearfish, He asked if he could swap rudders on my boat and try his on my boat so that's what I done and it performed much better on the water. I then tried it on my Vosper RAF Crash Tender and it just stuck to the water on any turn tight or wide. So I have done this ever since. On my Huntsman I had turned it over several times before trying this so I done the same on this and once again it was a lot better turning and didn't turn over. I don't like using large rudders if I cannot get one small enough for what I wan't I will get one and then cut it down. We used to race 5 or 6 boats on the water at a time and always needed to turn tight turns to get round the pond. Even watching Power Boat racing on the telly in the past they make tight turns to get round. I have a Probaot Miss Geico tunnel hull and straight from the box brand new the rudder on that has no leading edge and I can turn that flat out on the water with no roll at all. I suppose I am a speed freak and it has worked fine for me. Even if it is the wrong thing to do. The small avatar picture on my posts is a boat I have in Norfolk. This has a 1960 Volvo Penta outdrive probably one of the earliest one's made and that doesn't like to turn on 3/4 throttle without the engine revs dropping and digging in on a turn. I have tried this when out on open water up there. Don't try it now as got a warning from the Norfolk River Constabulary. Don't want to loose my river licence.
I find it hard to believe that people pay this sort of money for bottles of whiskey or even wines, just to drink them. Makes no sense to me. £12k is sheer madness. Does it make your Pee woth lots of money as well ??😤
What about adding a prop shaft support under the boat I useually add one something like this. I have never had one this strong looking but all ways had one just before the end of the shaft. you could also add one inside the boat or even a shaped wedge under the prop tube inside the boat. This will also help to stop any side whip on the tube.Another thing that I was taught was to do away with the leading edge of the rudder. Only have about one 16th of leading edge as this stops the braking effect when turning the boat at speed. That worked wonders on stopping the boat from digging into the water and doing tight turns as well. I'm not as experienced as a lot of the people on here but these are tip's I have learnt from others. Happy boating.
Hi canabus, could you please tell me what brushless motor's you have in your, Sea Hornet,Sea Commander and Sea Queen pelese. I have all three of these as well. Somewhere down the line I will be converting those to brushless. I don't understand all the electrical data myself. I do have a Proboat Miss Geico and she is awesome on the water at full speed. I have purchased the same motor and speed controller as what is in her to put in a new MFA Spearfish that I still have on the shelf in my work shed. I look forward to your set up's.
I think that we all have to do a bit of adjustment to the parts of most model's when building them. I cannot think of any model in the past that has not had to have any trimming of part's to fit correctly. I haven't purchased a laser cut model so I wouldn't know about them. But I would also assume that purchasing a paper plan this would also mean that there would need to be some trimming to part's after cutting them out. So if you are buying a plan then why not realise that you would need to trim part's once you have transfered them to wood or what ever you are making it from.I have purchased quite a few plans that were folded and once unfolded and then cut out and started building i have had to trim parts to fit. Why buy a paper plan if you are not happy with the way it is folded and arrives.