STRAKES what are the there for and what do they do and can they do anything for you??

[tunnels]

WHY HAVE STRAKES ??
what are the really doing for you?? they come in all sort of shapes and are in all sorts of places on any hull ! some are just classed as spray rails and nothing else ! some go from the front all way to the transom, others are cut short why ???, some are just short strakes right at the back !! there doesn't seem to be any set pattern as to there actual use so why have them at all ??

To me they can be very useful if used properly and how I think the should be used ! they are all to narrow ! and need to be wider and with shape ! the last part of a hull that's planning is where they should be and made to work and help lift the load up out of the water to reduce water drag . Yip water friction slows the boat and caused drag ! Experimenting with small boat its possible to completely change how the perform simply by making the old narrow strakes 1 1/2 wide strakes and making the 4 inchs wide ! the difference was amazing No im not into planning pads for every day use Strakes can help with chine walking as well !and with no pads boats in rough seas track dead straight and go where they are pointed and don't slip and slide all over the place !
So what are your thoughts and views on the subject !!

[XstreamVking]

Ask these guys about strakes, they could teach you all about them. If you want to know what works.

http://www.screamandfly.com/attachment.php?attachmentid=383095&d=1502223689

[tunnels]

[QUOTE=XstreamVking;2978818]Ask these guys about strakes, they could teach you all about them. If you want to know what works.

http://www.screamandfly.com/attachment.php?attachmentid=383095&d=1502223689[/QUO

Everything works its just a question of how well and does it do what its supposed to !!
Do you know all about those strakes ! why so there are many ??does it need that many???
Iv been there spent 4 years doing that kind of work , Including making steps building tunnel boats ! and introducing rocker with the high points of the steps !!

[AZMIDLYF]

383349

[tunnels]

383349
wow looks totally impressive and so many !! must be a hobby boat !!

[tunnels]

the actual shape of a strake is quite interesting and there's a few small things that no one thinks about !
should they be 90 degrees to the water surface or be turned down slightly maybe 2 degrees ? which would be better ?
Should the have a nice neat smooth rounded transition from the hull and out ?? or a prominent definite corner that is not rounded ?? what difference could that make ??
What about the very out side edge ! should it have a radius ?? or should it be a sharp corner ??
what about a very small kick down just at the very edge hardly even noticeable could that have any effect ??

[Jimboat]

the actual shape of a strake is quite interesting and there's a few small things that no one thinks about !
should they be 90 degrees to the water surface or be turned down slightly maybe 2 degrees ? which would be better ?
Should the have a nice neat smooth rounded transition from the hull and out ?? or a prominent definite corner that is not rounded ?? what difference could that make ??
What about the very out side edge ! should it have a radius ?? or should it be a sharp corner ??
what about a very small kick down just at the very edge hardly even noticeable could that have any effect ??
Here's some references to articles on 'Spray Rails (http://www.aeromarineresearch.com/tbdp6/strakes_and_sprayrails.html#Spray_rails)' and 'Lifting Strakes (http://www.aeromarineresearch.com/tbdp6/strakes_and_sprayrails.html#Lifting_Strakes)' and 'Spray Rail/Lifting Strake Design (http://www.aeromarineresearch.com/publications/PBR_feb2015.html)' that may be helpful. Info on differences in strakes and spray rails, also optimum shape/design/application of each.

[tunnels]

Here's an article on 'Spray Rail and Lifting Strake Design (http://www.aeromarineresearch.com/publications/PBR_feb2015.html)' that may be helpful.

Thank you Jim !! I have one of you older books some where from long time ago .
ME im a tunnel person and a total convert after spending 4 years working making plugs moulds and tunnel boats for Mr Scott Robson in new Zealand . Like nothing I have experience before or since !!

[wicheckmate]

Turned down 2 degrees, rounded transition, radius..... All small things all make big differences .

[AZMIDLYF]

Robson made some great hulls!

[tunnels]

38343232 foot 80 mph in any sea conditions, had accommodation for 4 adults with galley shower and toilet and performance that was unmatchable for any boat of its size !! WON best Boat of the year twice two years in a row at the BOAT SHOWs !!
383433 a small 5.1 mtr that could out perform any mono hull any where almost twice it size effortlessly!!! , best motor size was twin 70 hp Yamaha's !this was a very popular sized boat and after its face lift became a really nice boat !could be towed with a 1.6 liter car no problems
383434and my favourite the 23 footer capable of 60 mph with a pair of 140 hp Yamaha's in all and any sea conditions !, I personally built two of these boat myself !! side by side in our workshop and had the privileged of driving each of the finished boats for a whole day when they were finished ! had galley with 2 burner stove , toilet shower hot and cold pressure water system. chart table and accommodation for 2 adults and 2 children , the owner of one of these boats used to drive it full speed every where and on the open ocean in big swells jumped it like a giant sized jet ski and never had a moment of any dangerous happens never at any time in any situation !!


Robson made some great hulls!

Scott ROBSON is one very clever designer and made some beautiful looking boats, his tunnel design I feel is unique and all the boats I had the privilege to be a part of the development and building performed beautifully !!Its not just a straight tunnel down the middle it has shape from the very front and changes in different areas as it gets closer to the back and that is the secret !! how its done progressively is very very interesting and is proven with the outstanding performance and smooth ride of all his boats !
Race boat thinking and technology built into in extraordinary nice family boat with performance like nothing else on the market .
I know of no mono hull then or now that could come close to what his tunnels could do !!
I have looked and searched and never ever seen any where a similar concept tunnel configuration that he designed it is absolutely unique !! nothing even comes close .

[AZMIDLYF]

Thank you Jim !! I have one of you older books some where from long time ago .
ME im a tunnel person and a total convert after spending 4 years working making plugs moulds and tunnel boats for Mr Scott Robson in new Zealand . Like nothing I have experience before or since !!

Sorry, must have mistaken your reference here. :leaving:

[tunnels]

Turned down 2 degrees, rounded transition, radius..... All small things all make big differences .

Add all the small seemingly insignificant things and yes makes the difference between just being good and being awesome !!!

[tunnels]

Strakes I feel are much more useful than just a spray rail is all they seemed to be used for !
I have experimented of a few small boats and used them as lifting strakes and have been quite successful instead of pads or ski planks that seem to also have a limited use !!
By using wider strakes they make the hull more stable so doesn't rock from side to side, chine walking disappears at any and all speeds , by keeping the vee of the keel running full length the hull tracks straighter in moderately to rough water regardless what angle you run to the wave pattern so you are not continually fighting with the steering wheel . The other advantage with wide strakes is the hull planes quicker and stays on the plane at lower speeds . And if the hull has weight to wards the rear the strakes lift and hold up much better !

After reading some old posts on a couple of sites there are so glaring examples of people fitting strakes and expecting miracles to happen but that never happened !! , also spray rails producing wet boats because they had been made to deflect the spray ok but had never been angled down wards . !!
SO if you don't fully understand what you are doing and how you want things to work you better to leave it alone

[tunnels]

Turned down 2 degrees, rounded transition, radius..... All small things all make big differences .
I learned long time ago that attention to fine detailing really makes the difference between being just good !! and being really remarkable !! Water cling to surface and making small details to prevent water climbing and clinging to surfaces was something else hardly no one takes any notice of !! more detailing that's real necessary to make just being good ,much much better !!