There are two types of flow over a surface, laminar and turbulent as well as some transition region between the two. In ideal conditions with flat water there is some area at the front of the hull which will experience laminar flow.
The foils, which are fully submerged, will also expect to see laminar flow over some region. As laminar flow generates far less drag than turbulent flow it is advantageous to try and maintain it over as much of the surface as possible.
- Even in ideal conditions, all that is needed to trip the flow from laminar to turbulent is the smallest speck of dust.
- This shows the advantages of a perfectly clean and smooth surface. Imagine if the surface was self-cleaning and no specks of dust or growth could adhere to it!
- This finish must be maintained as only small imperfections will trip the flow - particularly important in the laminar and transition zones
While it is always worth aspiring towards the perfect finish on the foils, where it will be possible for some level of laminar flow to form, in reality we spend much of the time sailing in waves and it is hard for laminar flow to establish on a hull which may be leaping from the water.
- Once the flow has become turbulent this does not mean that the surface finish does not matter. A factor known as allowable roughness comes into play.
Allowable roughness is a way to quantify how smooth a surface of a given length at a given speed must be for no extra drag. It is to do with something called the Reynolds number or RN. In summary a shorter hull or foil traveling at a higher speed (high RN) will need a much smoother finish than a longer hull or foil traveling at lower speeds (low RN).
- Sailing boats are traveling faster now than ever. They have high aspect ratio foils (deep with short chord).
- High performance dinghies will comfortably plane upwind and foiling boats are hitting never before seen speeds.
- Dinghies can travel far in excess of the speed once done by yachts three times longer.
All of this means higher RN’s requiring ever better surface finish to minimise drag. This is the concept through which BoatSpeed was borne.
- Even a highly polished surface will under the microscope appear like a mountain range.
The smoother this surface is the lower the Sheer Stresses between the water molecules and the hull will be. This equates to:
- increased region of laminar flow
- thinner boundary layer (lower form drag)
- less drag in areas of turbulent flow
The BoatSpeed 4 step process will provide a smoother, faster surface than anything you have experienced.
Before any polishing of the hull it should be clean. Dirt can easily build up in the tiny scratches found on the hull surface
- NanoWash will penetrate and remove this dirt before any polishing.
- Polishing a dirty hull is bad as the dirt is much coarser than 1500 grade so will scratch the surface (causing more scratches).
Only use BoatSpeed NanoWash on a hull which has had NanoSeal applied – this will help maintain your NanoSeal finish.
How to apply
- Mix in a bucket of water – a good glug into a bucket if fine
- Mix up the wash with water so it foams and bubbles
- Apply to hull and allow to soak
- Hose excess from hull
5. Wipe dry with a BoatSpeed Detailing Towel
NanoShine takes traditional polishing wisdom by using a cutting agent to remove the worst peaks (1500 grade is very fine so the surface will develop a deep shine). This smoother surface is also coated with a light nano layer which gives protection from dirt and forms a perfect base for NanoSeal or NanoBoost
- Removes scratches down to 1500 grade
- Provides a hydrophobic finish
- Even used on its own it is a great polish for a smooth hydrophobic finish
- Recommended to follow up with NanoBoost before events or NanoSeal at the start of the season
- Perfect Preparation for NanoSeal
How to apply
- Apply NanoShine directly to the hull – evenly spaced out blobs (can we quantify this a bit better)
- Polish hull using circular motions – in hot climates a little water can be sprayed onto the hull to prevent polish drying out
- For best results use a powered buffer – if polishing by hand a BoatSpeed detailing towel is best
- As NanoShine dries to a haze, use a fresh section of the BoatSpeed detailing towel to buff to a brilliant shine
For next level protection and speed you need NanoSeal. Microscopic scratches are filled, maintain laminar flow over a larger proportion of your hull and foils. The super smooth finish will reduce drag and work as an antifoul alternative - too smooth for growth to adhere to the hull.
On topsides, NanoSeal, provides a protective layer which will help prevent scuffing from fenders, maintaining the perfect finish created with NanoShine.
Maintenance is reduced as in most cases only a light hosing with fresh water will clear any dirt from the surface. Salt marks can’t form as due to the superhydrophobic finish, water will bead and run off the surface. Contaminates in the water are also repelled so no scum from oils or algae can adhere to the hull finish. NanoSeal is perfect for reducing the time spent washing and drying water droplets from surfaces.
- Fills microscopic imperfections
- Perfectly smooth so nothing can adhere to surface
- No growth
- Antifoul alternative
- Reduced shear force between water and hull – lower drag
- No water marks – easier to maintain a perfect finish
- Super hard
- More robust and durable finish
- Protects paint and gel
- Impact resistant
- UV protection
How to apply
- Make sure the surface is perfectly clean – a wipe with isopropanol alcohol or white spirit is best for removing any dust specks
- Take your NanoFibre and wrap around your application sponge or fold in half and then half again.
- Apply a small amount of NanoSeal to the NanoFibre – a single line from one end to the other is perfect
- Apply to the hull and foils in a crosshatch motion working in meter sections
- Leave each section for approx. 30 seconds and then buff with a BoatSpeed detailing towel. Rotate the section of towel you use every couple of sections.
- Once your hull is fully treated leave for 24hrs for the NanoSeal to harden fully.
- Do not reuse a detailing towel after it has been used with NanoSeal. Any excess, buffed off, will dry very hard on the towel and if used again can scratch the surface.
NanoBoost is a fast, effective way to top up during the season.
At an event you apply a final touch up. Maybe you missed a few spots when the boat was on the trailer. You are under time pressure before racing but with NanoBoost just spray and wipe!
NanoBoost can be applied as a final speed coat straight over a hull polished with NanoShine or for optimum results a protective layer over NanoSeal. Also perfect for maintaining NanoSeal during the season and repairing any areas where NanoSeal has been abused
- Provides a Superhydrophobic finish
- Can be used as a short-term speed polish over NanoShine
- One event before re application
- Extremely fast to apply
- Spray and wipe
- Restore performance
How to apply
- Spray BoatSpeed NanoBoost directly onto a clean hull or foils
- Use a BoatSpeed detailing towel to wipe off immediately