Adjusting to keep nose up a tad?

[izcain]

So this should be like 30% or so by what I think your lookin for

[izcain]

I guess I dont understand how when I have the batteries in this spot the boat seems to do as described in the first post. Maybe something strut wise?

[properchopper]

Here are a couple of pics of the strut and the where the bat trays are mounted right now.

Here's my take : While strut depth & angle and CG play a role in ride attitude, one thing not mentioned so far is the lifting effect of the prop and rudder on the back. If your prop provides too much lift, it raises the tail and dunks the nose no matter where you set the CG. Likewise, a rudder set back as far as on your inline setup also provides a fair amount of lifting leverage and also dunks the nose.
I'd de-lift the prop and try an offset rudder which brings it in some. Of course offset rudders may not turn as well as an inline (depends on the hull), but cats like the Daytona aren't really known for carving turns at speed anyway.

[izcain]

What could be done to the prop to lose some lift. It has already been detouged so what other way would you suggest? maybe further detounging? Maybe another prop entirely?

I am interested in more of the top speed performance then the turning anyways.

Thanks for the replies I appreciate the input.

[properchopper]

What could be done to the prop to lose some lift. It has already been detouged so what other way would you suggest? maybe further detounging? Maybe another prop entirely?

I am interested in more of the top speed performance then the turning anyways.

Thanks for the replies I appreciate the input.

I'm relatively unschooled in prop modding; what I've learned so far is that de-lifting isn't done at the tongue, but at the trailing edge. Back-cutting the trailing edge (or Barr/hub/Texas) cutting is what reduces lift. Higher pitch props have more lift as well. Hopefully a good prop "knower" can give more input. I'd side-mount the rudder as well-way too much lift/leverage sitting as far back as it now sits. At least round the bottom.

[JonD]

Something sure is strange here. I have virtually identical set up in a Genesis (not a Daytona, so there may be some differences in hull weight or weight distribution etc)
4082 1550kv
Seaking 180
3s Turnegy 40C 5000 packs running at 6s1p
Strut is set even with the bottom of the sponsen
M445 Prop (balanced and polished)
and this runs fine at 33% COG, with stock in-line rudder, bottom of strut level with bottom of sponsons. I have about 1/4 - 1/2 degree prop shaft down at the rear - almost horizonatal.

I did enlarge the water inlet slots in the rudder quite considerably and this no doubt adds more drag, and hence may push the front of the boat down a bit. Never considered this before - thanks Propperchopper!

Sorry - I've run out of ideas.

Jon

[izcain]

Well maybe the extra 3 percent of cog would be what it needs also. I will look into the prop and rudder propperchopper! I want to change only one thing at a time though so I can see how it reacts and learn from it. I will start with moving the cog some to give me some more percentage and also maybe look at enlarging the hole as you have done also Jon.

You have almost the identical setup as me by the sound of it. It should work the same I would think.

[JonD]

I enlarged the rudder water inlet holes because I didn't feel that there was enough (or any) water getting through. That may have just been me being over cautious. I burnt the original stock motor out on its first run. Others don't seem to have had the same problem using the standard rudder. But I certainly have heaps of cooling water going through it now. Even at say 20% of maximum speed you can see it coming out of the outlet.

Rudder mod.JPG

Jon

[egneg]

If you cup the last 1/3rd of the leading edge it will narrow the thrust cone and you will have less lift.

[izcain]

Jon would it be possible to see a pic of what you did with your rudder please?

I will look into doing something with the prop. Temps are still very low with the M445 on there. I was wanting to prop up but I dont want to do that until I get it to handle what power it already has. Maybe I will change do as you suggest egneg and get that portion cupped but also get a M545 and M645 and have the same mods to them as well for a later date to run them.

[JonD]

Jon would it be possible to see a pic of what you did with your rudder please?

See two post below.

[properchopper]

Here's an example of a rounded rudder tip:

DSC03156.JPG

[izcain]

ok tonight I rounded the rudder just like in the picture you show and am now working on the cooling area

[izcain]

So today I went out and did some testing. With the cog at a much better spot (33 percent) and the rounded rudder tip and enlarged water pickup the boat worked great. It was much more stable and today I was able to finally get it going wide open. The system seemed much cooler also! Thanks for all the input guys!

[izcain]

I did end up having the move the strut up a touch as well.