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I know that after this long I should know all of this but I am not sure I do. I want to try to consolidate a theory of mine.
We know that the strut makes all the main adjustments, yes there is the Cg or CofG to deal with but that is another subject as far as this is concerned.
My mind tells me this.
Assuming the strut to be level the depth will alter the AoA of the hull, lower will raise the stern and load the props and higher will raise the bow and unload the props.
At the extremes we get it blowing out (too high) or over loading (too low)
I have also observed with my mini cat that if the strut is low the whole hull will ride higher and the chance of blowover is increased.
Now we can alter the AoA with the depth and also the angle of the shaft. prop end up naturally raises the bow and blowovers can happen if we go too high.
It is fair to say that these two adjustments need to be done incrementally to make changes and be observed or measured.
Here is the big bit.
My Big Cat runs real nice with the shafts 5mm above the sponson line and with 1.5 deg positive AoA on the hull. It is on the edge of blowover and a good gust of wind will do just that.
I have now hit it with more rpm 1800+kv instead of the older 1600kv and am concerned that it will blowover.
I know I can reduce the AoA or move the strut up or down.
Assume I keep the AoA the same, it rides nice this way. Do I go down on the struts to load the props and keep the bow down or do I reduce the AoA and start the whole tuning process form scratch.
I have so many ideas and scenarios in my head it hurts.
..............Yes I know I am a slow learner !!
Anyone want to shoot an opinion in here ?
We know that the strut makes all the main adjustments, yes there is the Cg or CofG to deal with but that is another subject as far as this is concerned.
My mind tells me this.
Assuming the strut to be level the depth will alter the AoA of the hull, lower will raise the stern and load the props and higher will raise the bow and unload the props.
At the extremes we get it blowing out (too high) or over loading (too low)
I have also observed with my mini cat that if the strut is low the whole hull will ride higher and the chance of blowover is increased.
Now we can alter the AoA with the depth and also the angle of the shaft. prop end up naturally raises the bow and blowovers can happen if we go too high.
It is fair to say that these two adjustments need to be done incrementally to make changes and be observed or measured.
Here is the big bit.
My Big Cat runs real nice with the shafts 5mm above the sponson line and with 1.5 deg positive AoA on the hull. It is on the edge of blowover and a good gust of wind will do just that.
I have now hit it with more rpm 1800+kv instead of the older 1600kv and am concerned that it will blowover.
I know I can reduce the AoA or move the strut up or down.
Assume I keep the AoA the same, it rides nice this way. Do I go down on the struts to load the props and keep the bow down or do I reduce the AoA and start the whole tuning process form scratch.
I have so many ideas and scenarios in my head it hurts.
..............Yes I know I am a slow learner !!Anyone want to shoot an opinion in here ?
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