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Re: My cx 25

Posted: Wed Jul 05, 2017 2:25 am
by dalnilo
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All the way and rewind as in the picture?

Re: My cx 25

Posted: Wed Jul 05, 2017 2:38 am
by dalnilo
Perhaps it is better to do so
Perhaps it is better to do so

Re: My cx 25

Posted: Mon Jul 17, 2017 3:42 pm
by dalnilo
Hello, i thought about changing splash rail, what do you think? For you as the best solution.
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Re: My cx 25

Posted: Tue Jul 18, 2017 2:42 pm
by dalnilo
can someone help me? how to do

Re: My cx 25

Posted: Tue Jul 18, 2017 4:31 pm
by narfi
I wish I knew more to help you.
In my HC14 and FS17 plans, it specifies a 1/2" radius needed for the glass to be able to lay over.

Maybe your CX25 plans specify a radius size for the weight of glass you are using?
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Sand down the point of your triangle to the shape of the circle on the outside, then glass it in.
Once that is done you can build up your point again with the appropriate filler to get your sharp triangle again if that is what you want.

Hopefully I am telling you the right thing, I have not done this, only studied alot :)

Re: My cx 25

Posted: Wed Jul 19, 2017 2:35 am
by Fuzz
Jeff can you make sure JM sees this? Thanks.

Re: My cx 25

Posted: Wed Jul 19, 2017 6:27 am
by Jeff
Fuzz, absolutely!! He will get this thread a little later this morning!! Jeff

Re: My cx 25

Posted: Wed Jul 19, 2017 12:44 pm
by jacquesmm
Let's not get too worried about strakes and spray rails. They are a good addition to a fast planing hull, not necessary on a slower one and the exact cross section does not matter too much.
The strakes full fill several functions. The most important one is to separate the water from the hull while on plane. This will happen with almost any section as long as the edge is sharp.
The strakes also help with dynamic stability: the tiny little bit of lift they provide add some stability but that lift is very small.
The last function is to divert sprays, again, no big difference between shapes.
Ideally, for the best lift, the surface should be parallel to the water but if I were to calculate the difference over the whole boat, we would be looking at something with 3 or 4 decimals.
For the best water separation, the surface should be angled a tiny little bit down but again, how much difference will it make?
To cut a square section along the diagonal puts you very close to the ideal strake. It will angled down a little bit and provide some lift.
It is a good compromise between water separation, lift and ease of building.
If you want more lift and less deflection, you can fill that corner as I see in the picture but I would not bother.
Each shape is good.
Two more points: you need a radius to glass them. Later, when faring, you should build up a sharp angle with resin plus a strong filler like glass strands.
That sharpness is more important than the angle.
Last point: don't compare to the strakes in production boats. Their size and shape is dictated by lamination requirements: you can't push glass in a small sharp corner (too much labor) and they don't want the gel coat to build up and crack. Do not compare, your strakes will be better.

Re: My cx 25

Posted: Wed Jul 19, 2017 2:15 pm
by dalnilo
Thank you so much for an explanation that leaves me no doubts.
Now I can proceed with more tranquility.
Since I have already glued one part is cut off the rest of the woods, I will proceed as you explained it to you without too much trouble.
Thank you again and sorry if I insisted for a clearer explanation.

With the translation from English to Italian it becomes all the more difficult.

Re: My cx 25

Posted: Wed Jul 26, 2017 4:15 am
by Bischoff
dalneilo wrote: Wed Jul 19, 2017 2:15 pm Thank you so much for an explanation that leaves me no doubts.
Now I can proceed with more tranquility.

With the translation from English to Italian it becomes all the more difficult.
Nice CX25!