Episode 5: Front and Rear Beams

 Episode 5:

 Right, so I have been forced by Brian (he thinks he is captain for some reason) to write something about the beams that hold the hulls apart, support the mast and the front edge of the trampoline!  He dumped them on me right at the beginning of lockdown (just when I thought I could have a nice quiet sabbatical.) so that I could not get bored.

They were looking like they needed some attention, and we were aware of a welded repair to the front beam on one side that needed checking to see if it would be strong enough for the trip. In my gusto I drilled out every rivet in the front beam and completely stripped it – discovering on the way that this beam has had a welded repair to both sides about 750mm in from the ends.

Also, the dolphin striker preload tube that locates just under the mast had snapped off inside the beam. (Man, am I glad we decided to strip the beam right down!)

                         


                                        

There were also some rather untidy aluminium plates fitted inside, around the weld repairs.  After some debate I removed these and we came up with a design for strengthening the beam internally at the repair points using some 6082 aluminium channel and box section.

The beam also had two preloading aluminium support tubes fitted to the inner beam bolt fixings – one had partly corroded away, so I made a new one using my very old pillar drill as a makeshift lathe.

Cutting and assembling of the beam reinforcement was a bit fiddly, but worked OK in the end with several dry fittings and minor adjustments. I finally fitted it in position with a bit of Sikaflex 292i.

The aluminium was a bit thicker than we really needed, but getting channel to fit box section and fit inside the beam proved to be a bit of a juggling act. (Ropes and shock cord also go right through the inside of this beam.)

                            

The mast foot had a ball bearing that felt as rough as my chin at the moment. Luckily the Tornado forum came up trumps and we were able to source a good second hand unit.

I then discovered you cannot use standard (cheap) rivets on boats! You must use Monel (expensive) rivets to hold everything together!  Stronger and corrosion free. I wished I had not been so active with the drill. (: 

However, the front beam all went back together with a few cleats and hooks left off. They will be refitted later when the boat is reassembled and position confirmed ones all our gear is fitted.

The rear beam was less problematic, but was also found to have had a welding repair, but in the middle this time.

I added a simpler reinforcement to the inside of the beam – all having to be glued in place right in the middle of the beam. (The beams are ten feet long.) This proved to be fun with everything having to be fitted using long bits of wood to get the aluminium in the middle and without getting Sikaflex everywhere. 

The main sheet traveller was found to have a mixture of 3/16^th and 5mm Torlon ball bearings. They are about half a mm different in size, so I have replaced the 3/16^th ones with 5mm.  There are 72 of these little chaps in the traveller and they are so easy to lose being camouflage brown in colour. Why aren’t they bright orange or something! Grrrr.  You have to work over an upside-down golf umbrella so you can find them when they ping out.

The rear beam did NOT have all its rivets removed, so was reassembled quickly.

 My next blog will be on the construction of the ‘racks’ that we will sit on when the wind is up. Apparently, we will need to go on ladder training to use them.  I’m not sure why we need them really as I know I’M strong enough to trapeze all the way round.

Sorry Skipper ):