Foils

[PAR]

It's a 13' warped bottom with little to no deadrise at the transom and an 18 HP 2 stroke pushing it, so high speed isn't going to be an issue.

Valve a 30" - 32" wide cutout, is the norm for your engine size, which does include room for controls and steering gear. You could go down to 26" - 28", but should check the "swing" of the engine with the controls and steering attached to see if anything hits or binds. Generally, you can use a narrower cutout if tiller steered, not so much with remote controls and sheering.

[valvebounce]

Originally Posted by PAR

Both of these ventilation plate foils work the same way. Some are designed for higher speeds and typically use a delta shape, while the lower speed versions look like stubby aircraft wings.

The logical thing would be to launch and try her out. The 18 may be just what you want, though the DoelFin will help you stay on plane at lower speeds.

Thanks PAR,trying the boat would be the answer,staying on the plane at lower speeds is my goal.

[valvebounce]

Originally Posted by PAR

It's a 13' warped bottom with little to no deadrise at the transom and an 18 HP 2 stroke pushing it, so high speed isn't going to be an issue.

Valve a 30" - 32" wide cutout, is the norm for your engine size, which does include room for controls and steering gear. You could go down to 26" - 28", but should check the "swing" of the engine with the controls and steering attached to see if anything hits or binds. Generally, you can use a narrower cutout if tiller steered, not so much with remote controls and sheering.

Thanks PAR,I will note the measurements down this time.
Best regards
V

[valvebounce]

Hi,
these are the pics of the boat when I first got it.
It is having a complete re-furb.The transom is being replaced with one that suits a longshaft outboard,new stringers that run lengthways only,a new deck,gunnels and seats.

[valvebounce]

Second attempt,I only uploaded one pic on the first one

[valvebounce]

Originally Posted by Jimboat

V - if you can send me a picture (email or PM) of your boat or post photo here, i will try to help. the effects of the fins will depend on the hull design and setup. They can help with getting on-plane, but can affect handling and performance at higher speeds. will help if i can see pic of boat.

Hi JB,I have posted a few pics of the boat,PAR says it is a 13ft warped bottom with little or no deadrise at the transom.
I am not having problems with it,but trying to find out the best way to set it up.
Best regards
V

[Jimboat]

very low deadrise, show should be very lift-efficient even at low velocities. Weight may be an issue to consider. if quick on-plane is your objective, then you should be able to prop for this performance. i suggest that you test the boat first, before implementing something like the "fins" or "foils".

[PAR]

Agreed Jim, but 18 HP is a bit on the low side for this little puppy. She should plane off, but may not have much reserve. The wise thing is to splash and see what happens, optimize the prop, then consider options, like anti-ventilation plate foils.

[Jimboat]

Originally Posted by PAR

Agreed Jim...The wise thing is to splash and see what happens, optimize the prop, then consider options.

Agree completely PAR. Performance could be analyzed, but it's much less expensive to test when complete, when the only consideration is use of foils or such.

[tunnels]

What are those things along the bottom of the hull ?? pads ?? Are they really nessasary ??

[valvebounce]

Thanks for your replies gentlemen,they are much appreciated,the weather here is looking more favourable,so I intend to carry on with the re-furb.
Getting the boat in the water to test it is paramount I can see.
I'll post pics as it progresses.
Best regards
V

[valvebounce]

Originally Posted by tunnels

What are those things along the bottom of the hull ?? pads ?? Are they really nessasary ??

Hi T,
They are the base stringers set in the original hull,the internal stringers are set on them.I am in the process of changing all the internal stringers in order to fit a new deck.The last owner had fitted crossways supports that followed the hull shape below the deck area,these had blocked the bilge water flow from bow to stern,which had caused them to rot.The new stringers will run bow to stern and be calibrated in height to enable the fitting of a flat deck,the deck will be the crossways support at that level.
The seat supports above deck will follow the hull side curvature and brace the sides of the hull,these will be fitted to the deck with s/steel brackets,and let into the gunnels with a mortice and tenon joint.[or similar]
A bit more than you asked I know,but as quoted here,building boats is a passion,not a chore.

[tunnels]

Bits of ???? or pads on the outside of the hull im talking about !!

[valvebounce]

Originally Posted by tunnels

Bits of ???? or pads on the outside of the hull im talking about !!

If you mean the white peices,they are home made rollers on the trailer and are not part of the hull.They will be replaced when I re-furb the trailer.

[PAR]

Yep Tunnels, we've discussed these "pads" before and they're part of the laminate, likely to stiffen the large, flat areas aft. The hull seems way over built, as far as laminate is concerned. You and I would cut those things off, but it's not necessary, so long as he's not interested in blasting past 30 - 35 knots.