Review of Shetland 640
Basic specs.
Looking for a new boat? Find a Shetland 640 or similar boat for sale
Both the hull and the deck is made of fibreglass. Generally, a hull made of fibreglass requires only a minimum of maintenance during the sailing season. And outside the sailing season, just bottom cleaning and perhaps anti-fouling painting once a year - a few hours of work, that's all.
The boat is equipped with 3 berths, a galley and toilet facility.
Unknown keel type
The boat can enter even shallow marinas as the draft is just about 0.61 - 0.71 meter (2.00 - 2.30 ft) dependent on the load. See immersion rate below.
The Shetland 640 has been equipped with different engine alternatives.
Alternative 1:
Shetland 640 may be equipped with an outboard gasoline engine at 15 hp (11 kW). Cruise speed is 5.0 knots. Max speed is 9.0 knots.
Alternative 2:
The boat may be equipped with an outboard engine at 125 hp (93 kW). Calculated max speed is about 20.8 knots
The fuel tank, which is made of stainless steel, has a capacity of 50.0 liters (13 US gallons, 10 imperial gallons).
Sailing characteristics
This section covers widely used rules of thumb to describe the sailing characteristics. Please note that even though the calculations are correct, the interpretation of the results might not be valid for extreme boats.
What is Theoretical Maximum Hull Speed?
The theoretical maximal speed of a displacement boat of this length is 5.9 knots. The term "Theoretical Maximum Hull Speed" is widely used even though a boat can sail faster. The term shall be interpreted as above the theoretical speed a great additional power is necessary for a small gain in speed.
The immersion rate is defined as the weight required to sink the boat a certain level.
The immersion rate for Shetland 640 is about 102 kg/cm, alternatively 572 lbs/inch.
Meaning: if you load 102 kg cargo on the boat then it will sink 1 cm.
Alternatively, if you load 572 lbs cargo on the boat it will sink 1 inch.
Sailing statistics
This section is statistical comparison with similar boats of the same category. The basis of the following statistical computations is our unique database with more than 26,000 different boat types and 350,000 data points.
What is L/B (Length Beam Ratio)?
The l/b ratio for Shetland 640 is 2.47.
Curiosities
In Denmark, you are required to have achieved a 'powerboat driving license' in order to sail a powerboat.
In this context a boat is considered a powerboat if:
Danish definition of a powerboat
Though, if you install a motor of 43 kW (58 hp), then the boat will become a powerboat, and you will need a Danish 'powerboat driving license'
Maintenance
When buying anti-fouling bottom paint, it's nice to know how much to buy.
The surface of the wet bottom is about 16m2 (172 ft2).
Based on this, your favourite maritime shop can tell you the quantity you need.
Note: If you use a paint roller you will need more paint than if you use a paintbrush.
This section is reserved boat owner's modifications, improvements, etc. Here you might find (or contribute with) inspiration for your boat.
Do you have changes/improvements you would like to share? Upload a photo and describe what you have done.
We are always looking for new photos. If you can contribute with photos for Shetland 640 it would be a great help.
If you have any comments to the review, improvement suggestions, or the like, feel free to contact us. Criticism helps us to improve.