Repair and Maintenance of a Drascombe Lugger

Replacing the Cast Iron Rudder Guides
(Page 2 of 2)

The first page of this project explained how the keel plank was partially unfastened and dropped down at the aft end of the Lugger. This enabled the old rusty iron lower rudder guide, which had worked loose, to drop out of its recess in the hull. The final part of the project was to prepare and attach the new bronze rudder guide. All this with the boat still on its trailer.

Preparing the New Bronze Rudder Guide

Next, the new bronze guide was prepared for fitting. I decided to replace the original 19 mm size 8 stainless steel self tapping screws with 30 mm long self tappers. In addition four M4 bolts were inserted through each corner of the guide, up through the hull, straddling the base of the rudder trunk in the lazarette (aft locker).

Photograph of the guide showing the guide depressions for drilling the holes Photograph of the Bronze Rudder Guide showing the depressions for drilling

The bronze rudder guides are not pre-drilled but on one side of the casting (shown in the photograph), six depressions have been thoughtfully provided which make it very easy to drill the 4 mm diameter fixing holes.

The top rudder guide is attached by four screws in each corner of the guide, represented by the four corner depressions. There are no holes made in the middle pair of depressions.

Normally, on new boats, the opposite arrangement applies to the lower rudder guide with only the middle pair of depressions being drilled out and used with two self tapping screws.

See sketch below for more details.

(Click on image for larger view)

Sketch of the Rudder Guide showing position of fixing holes Annotated sketch of the Lower Bronze Rudder Guide showing the positions of the fixing holes

Normally only the central pair of holes are used to fix the Lower Guide, using two 0.75" stainless self tapping screws. In my opinion, bearing in mind the severe knocks this guide is likely to receive when the rudder accidentally hits an obstruction, this method of fixing is inadequate. To make absolutely sure that the new lower guide would not work loose, I decided to replace the 0.75" screws with 30 mm long ones. In addition I drilled out the four corner holes and used M4 bolts to pass up through the hull and straddle the rudder trunking in the aft locker.

(Click on image for larger view)

Drilling the Holes in the Bronze Guide

All six holes were 4 mm in diameter. I found that the easiest way to make the holes was to mount the guide in a vice and use a hand drill. A slow drilling speed is essential to enable the bit to bite into the bronze and not overheat. After drilling, the holes were prepared to accept countersunk headed bolts by using a countersink drill bit.

Improving access to the Lower Rudder Guide Slot

Dropping the aft end of the keel plank a few centimetres was sufficient to remove the loose guide but did not provide enough access to allow drilling of addidtional fixing holes into the rudder-guide slot to attatch the new guide. The only way to achieve that is to pull the plank a few centimentres off-centre.

Using a looped rope to pull the keel plank to one side Using a looped rope to pull the keel plank off-centre

The easiest way to get better access to the rudder guide recess slot is to attach a rope to one of the rear mooring cleats, loop it round the dropped end of the keel plank and then pull sideways on the rope so that the plank is displaced by about 2-3 cm. The end of the rope is taken back round the rear mooring cleat so that the plank is held in its displaced position. The photograph shows the effect of doing this.

(Click on image for larger view)

Sketch showing the effect of displacing the keel plank Sketch Showing the Effect of Displacing the Keel Plank

The displacement of the keel plank by the method shown in the above photograph, is just sufficient to allow access for a drill to create new 4 mm fixing holes. This enabled the new guide to be screwed/bolted in place.

(Click on image for larger view)

Fixing the new Lower Guide in position on the hull

With the bronze guide drilled with six 4 mm holes it was time to finally screw and bolt it in position. The following sketches and photographs illustrate how this was done.

Sketch showing how the bolt holes were drilled Sketch showing how the bolt holes were drilled

The bronze rudder guide was placed in position in its slot and self tapping screws (used with the original fixing holes in the GRP), to temporary hold it in position. A drill with a long-reach 4 mm bit was then used to drill the two bolt holes through the GRP with the holes in the bronze casting acting as templates. After drilling the two holes on the one side, the rope holding the keel plank was then swapped across to the other side of the boat to displace the keel plank to the opposite side of the slot. This enabled the two holes for the other bolts to be drilled using the same method.

(Click on image for larger view)

Photograph showing one of the bolt holes being drilled Photograph showing one of the bolt holes being drilled

The rudder guide is in position temporary held by a stainless self tapper whilst the hole for one of the fixing bolts is drilled through the hull, using the casting as a template.

(Click on image for larger view)

Bolting and screwing the guide in place

With the preparation completed it was time to fix the guide in position. This was done as outlined below.

The guide is now securely attached to the boat.

Photograph showing the guide bolted and screwed in position The guide bolted/screwed in place

This photograph shows the guide secured in its slot beneath the hull with the four corner bolts and two stainless screws. The next stage is the re-attachment of the Keel Plank

(Click on image for larger view)

Sketch showing the guide bolted and screwed in position and the keel plank replaced Sketch of the completed installation

This sketch shows the completed installation with the Keel Plank re-attached. For the purposes of clarity the self tapping screw fastenings are not shown.

(Click on image for larger view)

Photo showing the four bolts securing the lower rudder guide in place at the base of the Rudder Trunk Photograph of the fixing bolts straddling the rudder trunk

This photograph looking into the aft locker/lazarette shows the base of the rudder trunking. The four fixing bolts for the lower rudder guide, bedded in Epoxy, are highlighted. To finish off, the bolts could be trimmed back to just above the nuts with a hacksaw and the tops covered with Epoxy filler.

(Click on image for larger view)

Photo showing the new bronze lower rudder guide in place above the re-fitted keel plank The completed project looking from beneath the hull

This photograph taken from beneath the Lugger on its trailer, shows the new bronze rudder guide bolted and screwed into place above the keel plank. The keel plank has been cleaned and coated with Burgess Woodsealer before being re-attached to the hull using the original two bronze bolts and three new stainless steel woodscrews. The bolts and screws were coated liberally with the mastic Sikaflex before re-attachment to maintain a waterproof seal. A cheaper alternative would be Silicone sealer.

(Click on image for larger view)

Project started and completed, May 2003

[Back to page 1, Removing the Rudder Guide]