The Orange Roughy project is quickly approaching the point where it actually looks like a finished boat.
The transom is done, the floor is done and the stringers and finished. The trailer is pretty much at the bolt-together stage and a 125hp Mercury Optimax is on its way to sunny Tasmania.
The guys at Penguin Composites have done an awesome job at doing the structural work on the boat, and as we approached Christmas the attention turned to getting the deck layout sorted and the positioning completed for the console and the other sundry elements.
The stringers were a big job – cleaning the old ones out was hard work, but fitting the new ones requires a keen eye and a steady hand.
Darryn Burr set the stringers up, ensuring that they were in the best position to handle the torque of the engine and the lateral and torsion stress that boats come under when thumping into rough water. These are significant stresses, and with such an excellent job done I have every confidence pushing the Roughy into some gnarly water.
The same goes with the transom – here hangs a 170kg engine plus all the thrust and torque that such a beast delivers. A 50mm double-glassed piece of marine ply takes the stress, which has been precision fitted to both look awesome and take the stress. It is made to fit a long shaft (25”) engine so as to eliminate as much as possible water coming over the transom.
This is important for the style of fishing that we like to do, which involves drifting and puttering around on Great Lake in a fairly decent chop looking for those surface feeding trout – the last thing we need is to be worried about water coming over the stern.
The trailer is pretty much ready for the various bits to be bolted to it and then registered.
The frame was welded up over a few days, and then another day was taken to weld in gussets to make it even stronger. The whole structure is made of 100x50mm RHS (rectangular hollow section) with a 3mm wall of good old Australian made steel.
As steel tends to move quite a lot as soon as heat of any sort is applied to it, it is important to be able to keep everything clamped tight in ‘jigs’ to prevent any distortion of the sections being made. If twists and misalignments occur at this stage then the trailer will never track truly behind the tow vehicle, which at best means excess tire wear and fuel consumption, at worst means upside down on the highway.
This is where the thought goes into trailers, as provision needs to be made for tail lights, wires, spring hanger position and where the coupling will go and so on.
The trailer has been fully hot dipped galvanised by Launceston’s Galvline, part of a national company. Mathew at Galvline in Launceston couldn’t have been more helpful, and his advice was great in getting a top job done. Holes and notches were put into the build so that two things could happen – one than the molten zinc can flow into and out of all the sections, and that the saltwater can also get out easily to eliminate corrosion spots.
Galvanising is a three stage process, with an acid bath to get rid of the scale, paint on the steel and any other nasties, a flux bath to make the zinc stick to the steel and finally the zinc dip. The ‘kettle’ in Launceston is 6.5m long, but only 1.2m deep, which means that it has to be double dipped. The trailer is 6m long, but 1.9m wide (without guards), so it had a lateral double dip.
Mathew’s advice was also to use a gasless mig welder or similar, it is almost impossible to get the flux from stick welding out of the welds, which can leave some points where salt can get in. My budget didn’t stretch to a mig, so I have a few spots to go over with cold gal paint.
I have opted to go with carpet skids as per the American bass style boat trailers use, and David at Penguin Composites assures me that the paint used is extremely tough and will stand up to it.
I made a template of the hull angle and marked the position of the strakes on it to ensure that the skids sit nicely between the strakes so as not to have any stress points. I can easily ‘shim’ the skids to ensure a perfect fit to the hull, and in any case, once the skids get wet they will conform to the hull as they dry.
The trailer is built in such a way that I can easily convert it to Teflon skids or rollers if I need to – hopefully I’ve got it right.
The way things are travelling we are well on track to have the maiden voyage sometime in February, fingers crossed.Reads: 1143