Review of Malö 40

Malö 40 anno 1977. Dragør Havn, DK, May 2025

Basic specs.

The Malö 40 is a sailboat designed by the Swedish maritime architect Bo Olsson in the mid seventies. The Malö 40 is built by the Swedish yard Malö Yachts AB.

In 1979 the Malö 40 got a taller rig and seperated keel and rudder. Hereafter named Malö 40 H.

Looking for a new boat? Find a Malö 40 or similar boat for sale

Hull

Both the hull and the deck is made of fibreglass. 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 deck is a sandwich construction which improves the indoor climate. Especially when the water is colder than the air in the cabin, then the double hull insulates against cold water and reduce the condense water in the cabin.

Interior

The boat is equipped with 2 cabins, 6 berths, a galley, 250 liters (66 US gallons, 54 imperial gallons) fresh water capacity and toilet facility.

The interior is like many other boats made of mahogany. Mahogany belongs to the hardwood species, known for being water-repellent and resistant to decay. It has an attractive wood grain and holds wood polish and varnish well.

Rig

The Malö 40 is built with a masthead rig. The sail area for the mailsail + jib is 44.0 m² (473.6 ft²). The advantage of a masthead rig is its simplicity and the fact that a given sail area - compared with a fractional rig - can be carried lower and thus with less heeling moment.

Keel

Keel of Malö 40 anno 1977. Kolding, DenmarK, June 2024

Full keel

The Malö 40 is built with a long keel. A long keel provide a better directional stability than a similar boat with a fin keel; on the other hand, better directional stability means also that the boat is more difficult to handle in a harbour with less space.

The keel is made of iron. Many people prefer lead keel in favour of iron. The main argument is that lead is much heavier than iron and a lead keel can therefore be made smaller which again result in less wet surface, i.e. less drag. In fact iron is quite heavy, just 30% less heavy than lead, so the advantage of a lead keel is often overstated.

The boat can enter even shallow marinas as the draft is just about 1.35 - 1.45 meter (4.43 - 4.73 ft) dependent on the load. See immersion rate below.

Engine

The fuel tank, which is made of stainless steel, has a capacity of 200 liters (52 US gallons, 43 imperial gallons).

Malö 40 may be equipped with an inboard Volvo Penta MD17C diesel engine at 35 hp (26 kW). The speed is 8.0 knots.

The transmission is a shaft drive. A shaft drive will in the long run require less maintenance than other types of drive e.g. a sail drive.

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.

Stability and Safety

What is Capsize Screening Formula (CSF)?

The capsize screening value for Malö 40 is 1.69, indicating that this boat could - if evaluated by this formula alone - be accepted to participate in ocean races.

Theoretical Maximum Hull Speed

What is Theoretical Maximum Hull Speed?

The theoretical maximal speed of a displacement boat of this length is 7.1 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.

Immersion rate

The immersion rate is defined as the weight required to sink the boat a certain level. The immersion rate for Malö 40 is about 173 kg/cm, alternatively 972 lbs/inch.
Meaning: if you load 173 kg cargo on the boat then it will sink 1 cm. Alternatively, if you load 972 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.

Motion Comfort Ratio

What is Motion Comfort Ratio (MCR)?

The Motion Comfort Ratio for Malö 40 is 25.0 - 32.8.

Comparing this ratio with similar sailboats show that it is more comfortable than 90% of all similar sailboat designs. This is a comfort value significantly above average.

L/B (Length Beam Ratio)

What is L/B (Length Beam Ratio)?

The l/b ratio for Malö 40 is 3.13.

Compared with other similar sailboats it is more spacy than 54% of all other designs. It seems that the designer has chosen a slightly more spacy hull design.

Ballast Ratio

What is a Ballast Ratio?

The ballast ratio for Malö 40 is 43%.

This ballast ratio shows a righting moment that is higher than 62% of all similar sailboat designs. A righting moment (ability to resist heeling) just above average.

D/L (Displacement Length Ratio)

What is Displacement Length Ratio?

The DL-ratio for Malö 40 is 240 which categorizes this boat among 'light crusers & offshore racers'.

54% of all similar sailboat designs are categorized as heavier. A light displacement requires less sailarea and has higher accellerations.

SA/D (Sail Area Displacement ratio)

SA/D (Sail Area Displacement ratio)
Indicates how fast the boat is in light wind:
- Cruising Boats have ratios 10-15
- Cruiser-Racers have ratios 16-20
- Racers have ratios above 20
- High-Performance Racers have ratios above 24
Sail-area/displacement ratio (SA/D ratio): 13.52

Over- / underrigged

The Malö 40 has more rig than 42% of all similar sailboats, which indicates that the boat is slightly underrigged.

RSP (Relative Speed Performance)

What is Relative Speed Performance?

The Relative Speed Performance for Malö 40 is 2

The relative speed performance is 2 which means that a it is faster than 2% of all similar sailboat designs.

Maintenance

Bottom Paint

When buying anti-fouling bottom paint, it's nice to know how much to buy. The surface of the wet bottom is about 28m² (301 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.

Rig

Dimensions of sail.

Are your sails worn out? You might find your next sail here: Sails for Sale

If you need to renew parts of your running rig and is not quite sure of the dimensions, you may find the estimates computed below useful.

**Guiding dimensions of running rig**
Usage	Length		Diameter
Mainsail halyard	24.6 m	(80.5 feet)	10 mm	(3/8 inch)
Jib/genoa halyard	24.6 m	(80.5 feet)	10 mm	(3/8 inch)
Spinnaker halyard	24.6 m	(80.5 feet)	10 mm	(3/8 inch)
Jib sheet	9.5 m	(31.3 feet)	12 mm	(1/2 inch)
Genoa sheet	9.5 m	(31.3 feet)	12 mm	(1/2 inch)
Mainsheet	23.8 m	(78.2 feet)	12 mm	(1/2 inch)
Spinnaker sheet	21.0 m	(68.9 feet)	12 mm	(1/2 inch)
Cunningham	3.6 m	(12.0 feet)	10 mm	(3/8 inch)
Kickingstrap	7.3 m	(24.0 feet)	10 mm	(3/8 inch)
Clew-outhaul	7.3 m	(24.0 feet)	10 mm	(3/8 inch)

Boat owner's ideas

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.

Finally

We are always looking for new photos. If you can contribute with photos for Malö 40 (Olsson) 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.

References

[Ref 1]: ISO 8666 Small craft — Principal data.
[Ref 3]: ISO 12215-5 Small craft — Hull construction and scantlings.