Trailer build ep10 - Hull side supports

 Teria's "Hull side supports" needed to be redesigned and built.

These are pieces of wood held up by steel posts off the trailer. The wood which can be carpet covered, rests under the bilge of the hull to hold the boat level on the trailer - important items of gear. (some boats use wobble-roller clusters in leiu of wood pieces)

The wood parts and  the steel yolks that held them were re-used. But below that everything was changed.

The support posts went from 15x15mm soilid square bars to 40x40x3mm SHS (square hollow section) allot stronger looking.

The attachment or mounts to the trailer had to be changed too. The original mounts were welded on 20x20mm SHS with a lock bolt which were discarded in favor of U-bolts and plates to grip the trailer frame.

Dismantled original hull side supports

New and old support posts and yolks - note angle of yolks

Before cutting off the old yolks, the angle was measured and transferred to the new steel posts.

Old yolks cut off and cleaned up a bit

As well as the tops being angled, some holes were made to allow for hot dip galvanizing process in future.

Tops of 40x40mm posts prepared - note galvanizing holes cut in before assembly

Yolks welded to posts

 The support posts were attached to the trailer frame by U-bolts and plates. No such plates were available in all the marine stores or even a trailer manufacturers. so had to design and build my own ones.

I563 trailer - Dimensions of plates for U-bolts holding hull side support posts.

I took the design to a local steel engineering workshop (Les Wells steel) and had the plates made up for $17 each.  The service is great. My original plan didn't make the holes large enough, so had to round file the holes larger at my workshop. The revised plan above specifies 15mm diameter holes (to take 12.5mm U-bolt stems after galvanizing of plates)

The system bolted together OK. The U-bolts are made of heavy duty 12mm rod , are about 5" long and 40mm wide inside. (some i looked at were far lighter). Ny-lock style nuts are used.

New galvanized bolts were fitted to the yolks, through the wood hull support.

Forward Hull side support, loosely fitted.

Four hull side supports

The length of the 4 posts is a bit long for now. Once the boat is on trailer then can cut off the excess post below the frame if required.

Aft Hull side supports

I'd like to thank the investigator owners on the I563 forum for the discussion about how to build such devices, many if not all the ideas for these hull supports (also known as 'Bunks") came from Investigator 563 forum members.

One reason for this choice of design is that they can be moved about on the frame (as well as critical height adjustment) and also removed easily for maintenance. Another is they're far stronger.

Trailer Build Ep9 - Keel rollers

Bought and fitted new 8" keel rollers to the lower main frame. Red for fiberglass hulls. The rollers support frames attached with galvanized saddles welded to the frames. These have 12mm bolts which tighten onto square solid bar posts.

Fitting the first roller set on the aft frame (F1)

I bought these from NQ wheels and Castors in Townsville, which sell high quality products and the service is quick and efficient.

The aft double rollers can tilt..

..to match the angle of the stem

Fitted 3 double roller sets aft to take the bulk of the keels weight, so 6 rollers to replace 3 previously. Hope that the load is more evenly distributed this time around and no roller pins get bent again.

Keel red rollers fitted - Blue keel guide rollers have double saddles.

Aligned the keel rollers with a stringline running down one side of the rollers. Clamped the saddles to the frames and weld tacked in position. The forward 6" red roller and gal frames were new, but used recycled frames on single 8" rollers F4 and F5 and recycled the F5 red roller.

Once everything was aligned, all the rollers and supports were removed. Then the main frame tilted onto it's sides so the saddled could be fully fillet welded on (downhand)

Saddles tacked on and ready for downhand fillet welding to frames.

Wreck of the SS City of Adelaide (Dinghy sail-row #45)

There are quite a few shipwrecks on Magnetic Island, so decided to visit one on 4th June 2018 -

The wreck of the SS City of Adelaide  rests on the tidal flats about 300 m from Cockle Bay, near the SE corner of Magnetic Island. I first found out about it in a news article, (then found that there's a "wreck trail" for visitors to the Island)

A brief History

The SS City of Adelaide was built in Glasgow, Scotland in 1863 and launched as a 263 ft passenger steam-ship operating between Melbourne, Sydney and across the pacific to Honolulu and San Francisco until 1890.

SS City of Adelaide circa 1864 (credit, Wikipedia)

In Sydney she was converted an operated as an engineless 4 masted sailing Barque through the 1890's.

City of Adelaide Barque rigged circa 1892 (credit, ABC net au)

In 1902 she was stripped and became a coal storage hulk in Townsville, until she caught fire and burnt out in 1912. In 1915 the hull was being towed to picnic bay to be scuttled as a breakwater, but it grounded permanently at Cockle Bay where it remains to this day.

Dinghy trip #45


On the day the tide and winds were right and the family was busy, so snuck off for an afternoons sail to visit the wreck site.

Cape Palleranda ramp is about the closest point on the mainland. The ramp was sand free which is fairly unusual, the city council workers had pushed the sand off recently, so my 2WD trayback ute could drive the trailer all the way down. Set off around 11am into a total flat calm, so rowed all the way across. The only mishap was an oar rowlock repair but fixed that with some braided twine. It took over an hour as it's about 4 nautical miles.

Palleranda ramp -  View to Magnetic Island 

Oar repair

Middle reef navigation marker, Townsville coastline behind

I also planned the trip so the tide was rising near high tide , so the crossing of the extensive reef flat area was safe with no chance of being stranded.

Magnetic Island fringing coral reef

It was nice to glide over the coral reef under oar power and eerie stillness, the surface like a huge glass pane. Had about 1-2 foot of water under the dinghy. The coral reef seemed to be in reasonable condition, coral bleaching was minimal. It's not something you would try when the usual wind is blowing and the wave chop makes the coral hard to see and easier to strike.

The 103 year old wreck is well camouflaged when approaching over the reef flat from the south west

The wreck is well camouflaged against the Islands hills - it is nearly dead ahead

Wreck becoming more discernible from a few hundred meters away

Finally got alongside and was able to row (and scull) around. The wrecks on a sandy/muddy bottom about 100 m out from the mangroves on the island. The was about 3-4 feet deep of water around the high tide of the day.

Only the bottom quarter of the hull is now left, all above that has collapsed into the sea. Mangrove trees grow up from the muddy hull and it forms an artificial island in which sea birds roosted.

The stern post and propeller aperture

Exposed ribs along the port side

Sea bird fly off, mangrove roots growing through

A section of fallen hull side

The bow - the stem post fell away to the side

A gaping hole in the starboard side with some fallen hull ribs in front (also some steel mast remains)

Dinghy anchored along starboard side into shade of mangrove tree

A nice place to have a peaceful lunch break

View looking away from Island

The view of wreck if approaching from Picnic Bay through the Cockle Bay channel.

It was good place to have lunch given the flat calm conditions and shady Mangrove trees growing conveniently out of the wrecks hull.


To Picnic Bay and home

Shipped both oars again and rowed along the coastline to Picnic Bay, turning every now and then to peer over the shoulder for navigation. Passed Cockle Bay which has a nice a hard gently sloped beach, good for drying a boat out between tides.

There's a shallow tidal boat channel, with a sandy - loose rock bottom, near the rock shore which runs around the headland into Picnic Bay (inside the fringing reefs)

The coastline from Cockle Bay towards Picnic Bay.

Rested up at Picnic bay beach, then sailed out and caught an easterly wind back towards Palleranda.
The wind died a mile or so out, so rowed the final bit to the mainland.

Sailing from Picnic Bay

Back at Palleranda ramp

On the trailer, heading home for a good rest.

References

ABC news article - "Magnetic Islands forgotten shipwrecks.."

Whats on Magnetic Island - Shipwreck trail

Wreck of SS City of Adelaide (credit, ABC news)

A good drone video of SS City of Adelaide wreck by DroneHack productions


Recently found that there is another surviving ship with a similar name from the same era

Clipper ship "City of Adelaide"  which was saved from demolition in Scotland and bought back by barge to Adelaide, South Australia for restoration. This ship did 25 runs from UK to Adelaide bringing early settlers over and transporting cargo back. She is the only surviving "composite" ship in the world (the other being the famous "Cutty Sark" which was partially destroyed by fire)

She is opening to the public as a museum ship in March 2022

Clipper Ship "City of Adelaide" website

Trailer build Ep8_extra frame bracing

Added increased strength to the trailers frame and drawbar in the form of extra bracing.

The ideas i used came from trailer sauce website (draw bar design) and the investigator 563 forum.

Used 12mm solid rod bracing ("ladder style") on top of the main frame. The uprights were 75mm (3") long.

The idea is to prevent any chance of  frame failure when loading or offloading the boat. The vertical height of frame and brace is now 6" (150mm) so should be at least twice as strong to bending force as the original 3" RHS design (but extra weight is minimal).

Ladder style bracing 

The drawbars 25x6mm flat bar brace was offset to one side. It was intermittently welded (1" welds) on alternate sides at 6" spacings. The flat bar was grinded and zinc primed where it contacts the RHS before attachment so no rust can develop in the join crevice.

The 1" brace (and not a rod ladder) was used to maintain the lowest possible profile and have some strength if the lengthy draw-bar ever grounds out (eg if going over a sharp crest , like where a boat ramp joins the tarmac roadway)

Drawbar pivot end for tilt trailer, holes are for hot dip galvanizing process. Flat bar Bracing extends full length of draw bar.

Back to the main frame - Welding the rod bracing was aided by tipping the frame over on either side and also upside down, so downhand welding could be done. Although i began by using an overhead chainblock, soon realized i could do some free weightlifting training too and lift the frame sideways by and just prop it up with a timber.

frame upside down for downhand welding of the underside.

Close up of ladder frame welding

Side propped for more down hand welding

Trailer rebuild Ep7 - frame welds, wheel assembly

Used a 1/2 ton chain block slung off a stout rope to lift/ flip the frame over easily.

Frame separation _the old and new

Cutting up the old frame

Welding joins up with 2.5 mm rods

Welding all joins down hand - flip frame over to do other sides

Fillet welds

The running gear needed a clean up, one wheel was seized. So dismantled everything there.

Hub and spring assembly inverted for disassembly, axle u-bolts at top

The wheel seizure was caused by rusted (and expanded) brake pad backing plates. Unbolted the U bolts holding the wheel assembly's on, unbolted the leaf springs. Bolt threads etc were a bit corroded so it took awhile with penetrating oil and elbow grease.

Dismantled for maintenance_axle and hubs

Unbolted the brake calipers and removed the brake pads. These needed rust treatment, chipping layers of rust away, one pad was de-laminated from its steel backing plate so epoxy glued it together. Cleaned axle grease out of the inner hub with old newspaper (it squeezed past the inner seals due to bearing buddy grease pressurization) The bearings seemed OK as they always were well greased by the bearing buddies. The hub housing and brake discs are a very robust looking design, (the brake discs are about twice as thick and smaller diameter than the ute's front disks_which, by the way, were recently honed and re-padded by a local mobile wheel specialist)

Temporarily reassembled the brake callipers and pads so as not to loose any critical components (being a vintage era trailer they could be hard to find)

Wheel hub bearing housing and disc brakes

Started rust treatment on the parts. Chipping and phosphoric acid. The axle wasn't too bad_ its made of 40 mm solid rod bars, very heavy construction.

 The box beam (for the leaf spring attachment) on the mudguard needed more work. These fittings have probably never been separated from the trailer frame for decades, so crevice corrosion occurred between them. The trailer was coated in a high build epoxy paint though which kept allot of corrosion at bay but once rust get underneath the paint it is lifted off.

The mudguard box bar_hollow and sealed at ends so no internal rust. Good for a restoration on the exterior surfaces.

Trailer frame finishing work. Trimmed the end beams off, welded on brake wire eyes (made from heavy chain link) and ground-off welded joins and sharp edges etc.

Possible keel slide beams with an aft roller

Started thinking about the keel roller refit. There is nearly a ton of boat plus gear weight concentrated over the aft three frames, at least one roller pin had bent which prevented turning under load which was probably one of the the hidden causes of the boat getting stuck on the trailer when launching.

Found that 4x2" hardwood beams fit nicely on the aft frames, leaving a 15 mm gap between (for a water hose jet to clean the centerboard case). These can bolt on to the beams channel flange and would be capped with teflon-like plastic for easy keel sliding. Rollers can then be fitted fore and aft the keel slide woods. The only downside would be crevice corrosion between wood and galvanized steel beams_ maybe some mastic could keep the salt water out between maintenance checks.