Well it was abiut time the finger was extracted again on the 'ducer, yesterday I finally had a few hours free so it was back to work.
Work started by taking the angle grinder to the back of the mounts to cut down the overhanging thread from the rubber isolation bobbins.
With this done, I could mount the engine on the mounts and get it into the correct position in the boat (17 inches from tip of glowplug to the inside of the transom board, with a 5" legnth of 1/4" brass tube in the motor, with the end of the brass touching the bottom of the boat for the right angle). This was then marked for drilling, having checked that the engine starter belt has got enough room to slip out when the engine has started. The drop mounts allow you to get the flywheel almost touching the bottom of the boat, so it's important to make sure you can get the belt in and out.
With this marked, I could then use a right angle drill to drill out the rails. The whole lot is secured in with M5 bolts, with penny washers outside the rails. It is important to seal the wood so any water ingress won't decay the rails over time, so I just mix and poke in 5 minute epoxy whenever I drill holes through the wood.
With this done, I moved on to the transom hardware. I started by masking taping the whole transom, then drawing reference lines of where everything needs to work from. I started by drilling the 1/2" free flood / drain hole round the shaft exit. From there I lined up the strut and rudder, marked and drilled for each.
My only one complaint about the Seaducer hardware pack is that the screws aren't really the highest quality, but no matter as they'll probably never need to be removed. Jerry's machined hardware is second to none, it's of excellent quality and the material used is very high grade. What interested me about the strut in particular is that it has a 3 degree offset machined into the leg, to couter prop effects on the boat. Clever tricks - and why everyone says that if you don't use the Seaducer hardware the boat will never run right...
Lastly for the transom hardware is the pipe mount. The base is lined up with the inside of the strut so the excess arm if needed can fit in the gap between the strut mounting points. Unfortunately the on part I didn't take in to work (where I'm building the boat) was the pipe, and as it turns out all my pipes are too long to use the kit end mount (in the US they run unsilenced pipes which are a good 6" shorter than the silenced pipes we use here). No bother as Prestwich Models do a 50mm pipe mount that will hold my pipe and fit onto Jerry's mount. Win
Not pictured, I also marked up where the turn fin will place and notched the deck of the hull to fit it in to. I also marked and drilled the mounting screws, though have not mounted the fin yet as it is incredibly sharp.
Next up is cutting the rudder down to height. Using a 24" ruler along the bottom of the hull I marked the point where the rudder blade is in line with the hull, then a square line 3 3/4" down the blade from that point to cut the blade to.
Last for today was mocking up the positioning for the servos, I've gone for a total deviation on the instructions here as I despise the use of wood on glassfibre in radio boxes. I've gone for all ally mounts bolted through the bottom of the box. The throttle is top left of the picture, rudder bottom left and mixture bottom right. There is plenty of clearance top right for the 2000mah 7.4v Li-Po and reciever to be placed, with room to the right of the mixture servo for an Ian's Boats waterproof switch. I'll be replacing the macine screws in the picture with button head M3 screws from the outside in, as the washers and lock nuts foul the bottom of the boat if on the outside of the box.
Lastly for this installment was mounting the pipe pressure filter / cooler, this is a unit from Answer RC that will help to reduce the amount of detritus that will find its way from the pipe into the tanks. It came with its own clip mount that is threaded underneath for M3, so I drilled and tapped the rail M3, then epoxied in a length of threaded brass bar.
Next up will be the shaft stuffing tube, shaft bearings in the strut and mixture control mount, then it's pretty much on the home straight from there
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Topic: Seaducer 45 SD3 NM Build (Read 222 times)