“Go Faster” Fairings Go faster?... well not really! But if you're feeling bored one warm afternoon and fancy “supercharging” your Catapult you could try this. It might just give you the psychological edge: Fig 1 shows my front daggerboard channel with the new fairing attached plus a modified rear daggerboard channel (see repairing centreboard and rudder foils article) for why the rear channel is modified... The fairings are made from aluminium angle off cuts 40x40mm x 2mm wall thickness, which I happened to have. If you'd like a 300mm length free for this job, send me an email and I'll bring some to a Catapult TT event for you – [email protected] Cut 2 x 100mm* 110mm lengths off the alloy angle and file off any sharp edges. Grip both outer edges in a vice and gentle squash the 90deg angle down to approx. 35degs. Fig 1 shows the 100mm length fitted. Note that mine falls short of the cross member. Cut it to 110mm if you prefer it to. Test your squashed alloy angles (now technically called “Fairings”- Woo-hoo!) Fig 1.Fairing on front daggerboard channel. against a front daggerboard channel. *100 mm length shown: 90 –110 mm options. You'll find a couple of ridges on the channel that are ideal for locating the fairings in. Gently adjust the fairing angles until they fits snugly on either side of these ridges. Depending on the length of fairing you decided to make, you may need to cut some notches out of the corners, See Fig 1: If making the short 90mm ones you won't need any notches. Leaving the fairings slightly short of being full length at the bottom should help avoid catching them when rigging the boat on a hard surface.

Fig 2: Brackets. Cut one side to 15mm and one side to 30mm before bending it over.

(Return to Catapult Home Page) (Return to Repairs and Mods Page)

To make your fixing brackets, start with two 25mm sections cut from some surplus angle alloy. Cut one leg down to 15mm and the other leg down to 30mm. Then bend the 30mm leg 15mm in from the end. When bent this will form a mini channel. Bend both legs in past 90 degs as shown in Fig 2. You'll now have to do some trial and error bending to get your brackets fitting nicely inside each fairing. Make your second bracket. Looking down inside the fairing in Fig 3, you'll see that the manufactured angle remains sharp while my own bend has a slight radius. (Don't try to obtain a sharp bend or the alloy may crack). Drill one central hole in each bracket for fixing it to the channel. If fixing through from the bracket side into the daggerboard channel with a screw, remember to break or grind the point off afterwards. If fixing through from the daggerboard channel side, the rivet or screw head will need to be countersunk to lay flush inside the daggerboard channel. Fixing the brackets. Hold the bracket positioned as shown in Fig 2, against the daggerboard channel and about 50mm down from the end. Use a pencil to mark through the hole in the bracket to indicate the position for the the fixing screw hole. Centre punch the mark, then drill through the channel. Change your drill bit size to suit the self tapping screw or pop rivet being used. Fix the bracket into position using your chosen method. Repeat on the other side front channel.

Fig 2. View to show simple bracket made from angle alloy

Temporarily fix the fairings using electrical tape or wire wrapped around the top and bottoms. Now measure the position for your fixing holes so as to meet the centre of the bracket legs.

Drill very carefully through the fairings into the fixing brackets to avoid bending them. Secure using alloy pop rivets, or stainless steel self tapping screws. Remove the temporary tape or wire.

(Return to Catapult Home Page) (Return to Repairs and Mods Page)

Don't forget to snap or grind off any projecting screw threads from the inside of the daggerboard channels, or you'll be wondering why your daggerboards won't go down. Job done... If the above seems a bit too involved, or metalworking isn't your thing, an alternative “cheap and cheerful” method has been used by Alastair Forrest (Club Chairman and Webmaster). This involves making the fairings from hardwood, which can simply be glued on, or screwed in place using stainless steel or brass countersunk screws from inside the daggerboard channel. A coat of silver paint will make them blend in to look the part. Much simpler if truth be told.

END

(Return to Catapult Home Page) (Return to Repairs and Mods Page)

First Published February 2014 Reviewed November 2016