Are you moved by your beam clips?
by Brian Phipps
This article originally appeared in the Winter ’97 Issue of “The Art of Dart”, UKIDA’s Class Association Newsletter.
The Dart, being a “one design” craft with accepted tolerances, sometimes needs a bit of attention to keep it operating at full performance. The rear beam clips often get ignored, viewed as the things that hold the hulls together.In fact they are much more important than that, they are a tuning device allowing small movements of the rear beam position, securing hull alignment. To check that they are doing their job correctly, measure your hulls centre line to centre line, and adjust the clip (DB165) so that it just slides over the edge of the hull. This can be done by loosening the adjustment nut (DB166), sliding the clip and re-tensioning.
Packing out the inner thrust pad to prevent excessive hull movement is optional but normally not required. Having secured the alignment of your hulls you may wish to prevent the beam clips from re-adjusting under load, this is best done by’filling the slotted holes in DB164, around the adjuster nut, with epoxy and allowing it to cure. When inspecting a rear beam, especially on older craft, if the tolerance between the beam housings and the beam is becoming excessive it can cause large amounts of hull movement. This can often be observed by bent beam clips or a solid “clunk” after each tack, as the hull is forced back in against the thrust pad on the leeward side. To rectify the situation re-gelcoat the inside of your beam housing and carefully re-file the aperture. Hull alignment is the first step before checking rudder alignment, as it directly relates to the required length of the connecting bar. So next time you go up the beat in a force 4, cranked in with your crew on the wire, give a little sympathy to your rear beam clips and check they are doing their job.