Guide to Solo Trim & Tune
I have only just started sailing the Solo after a twenty year lay-off from Sailing. They say the Solo is a relatively simple boat to trim but that boat speed advantage is very difficult to achieve thus making the racing super competitive – as a Musto Skiff sailor described it “muskets drawn, hand to hand combat”.
So as I get back into practice and learn about the Solo I will be collecting my experiences referenced against the published advice for future reference – these are my notes. For now, my experiences will be based on a 1996 Severn composite with Superspars M7 Mast flying Edge (apparently quite a flat sail) and Hood sails.
The first bit of good advice I’ve been given is to make everything reproducible. So for example have marks on the fixed piece of kicker so you can see the position of the kicker pulley (Griffiths)
In the document I will talk about normal, light, powered and over-powered conditions – although this is helm and rig dependant it is based around the following categories given by North:
- Light – 0 to 5 knots – sitting inboard
- Normal – 6 – 10 knots – sitting on the sides
- Hiking – 11 to 16 knots – hiking out
- Over Powered – 17 knots +
Mast Set Up
The default setup for a mast has varied with time and currently the trend is to maximise mast rake in order to improve upwind performance. New build plastics such as the Winder have their front bulk-heads further forward to allow for greater rake.
Depending on where you sail you will want to set different mast foot positions (North)
Flat water (inland conditions)
- 0-16 knots – 3052mm
- 16 knots + – 3065mm
Choppy/rough (sea conditions)
- 0-12 knots – 3052mm
- 12 knots + – 3065mm
Having less mast rake in light conditions is supposed to help with dead running as the boom can be pushed out further. The effect on beating is thought to be insignificant (Griffiths).
The Forestay should be set, with the sail down, so that with the mast touching the rear of the gate the stay is just in tension. If the track has been cut out to promote mast rake the mast should be 5mm from the rear of the gate (North). It is better to have it more slack than tight (McGregor).
Adjusting the Forestay as wind strength changes
In drifting conditions release the forestay 2 holes (Speed, Kimmens). This max-aft position promotes mast bend and flattens the sail which will allow the leech to open, promoting more air flow, life and hence boat speed (Greenwood). As conditions improve you may reduce this to 1 hole before setting to neutral in normal conditions.
The Shrouds should be set such that they are just in tension when the mast is pushed forward in the gate. At what position this occurs depends on the guide you read and seems dependant on rig, weight and required de-power:
- The default appears to be 5mm (Greenwood, North).
- Increased to 10mm if you are over 85kg or sail on flat water (North).
- Aim for 10mm unless you are over-powered and want the rig to breath more, in which case aim for 5mm (McGregor).
- Selden C masts should leave 10mm (Speed).
Current thinking suggests that the mast should be held ‘still’ in the mast gate. Side to side movement can be prevented with tape. Forward/Aft movement restricted with chocks.
Under normal conditions the chocks stay in front because this straightens the mast, gives the sail its natural shape and powers up the rig (Speed).
In lighter conditions chocks should be placed behind the mast to promote mast bend and flatten the sail. This is because slow moving air finds it harder to move around a curved surface (Speed, North). However, you may decide just to remove them as putting them aft reduces feel and promotes lots of lower mast bend (Greenwood). You may also choose to leave them forward (Kimmens, McGregor).
In strong conditions and when overpowered they will typically stay in front (North). However, you may decide to remove them if you can’t get the forestay to slacken (Kimmens). However, removing the chocks takes the power from the bottom of the rig and not the top which isn’t always helpful (McGregor, Griffiths). Removing them during a race if the wind strength has increased is useful. However, if you are rigging for those conditions leave them in to support the mast and direct the effect of the kicker to the middle of the mast where it will have most effect (Greenwood).
Depowering the rig
To depower the Solo rig you should apply the controls in the following order. Rather than pull each one on fully, each should be progressively adjusted before repeating 1 to 4 (Kimmens).
- Cunningham – to free the leech (Griffiths)
- Centreboard – to reduce weather helm(Griffiths)