Re-maiden of a Racing Sparrow prototype
Refurbishing my RS750 model yacht has been a fun little project for me, as I have always loved sailing and working on boats. When I first acquired the boat, it was in a sorry state, with a dirty hull, damaged rudder, and missing spreader. However, I was excited about the prospect of bringing this cool old model back to life.
The first thing I did was to take it back to my little workbench and inspect it thoroughly. I carefully examined each part, looking for any damage or wear and tear. I then gave the boat a quick clean, removing all the dirt and grime that had accumulated on it over the years in my Dad's garage.
Next, I tackled the damaged rudder. It had been chewed up by a small dog at some point plus the diameter of the rudder was about 8mm. Very large with lots of play in the rudder and linkages. Not to mention a sinking hazard!
I used 15min epoxy to fix the old rudder. I dug out the old rudder stock and installed a new smaller brass rod 4mm. I also patched up the dog bites with epoxy, using gaffer tape to mask off the aerofoil shape. Wait 15 minutes then peel back the tape and you have very little sanding to do have a smooth rudder blade. A great technique for fibreglassing work or patching small scratches or holes. The epoxy won't stick or bond to many types of tape.
I also needed to install a new rudder stock into the hull. I simply super glued the smaller tube into the larger tube. Once in place I filled the gap around the new stock with epoxy. It was quite a simple job in the end to reduce the rudder stock diameter.
All up the new rudder upgrade has made the boat far more responsive and easier to control. It has nice firm linkages with little play and a large rudder blade.
I used some brass rod to create a new spreader that was identical to the original. This was missing when I found the boat. A simple part to make and replace.
To keep costs down, I decided to use the same servos that were mounted in the boat from 13 years ago. These servos had held up well over the years, and I was confident they would continue to perform well. However, I did replace the old 27mhz receiver with a new radio master R86C receiver. This new receiver had better range and was more reliable than the old one.
I also decided to upgrade the transmitter, as the old Futaba Attack 2ER kit was outdated and no longer met my needs. I opted for a new Radio Master Zoro transmitter, which was a huge upgrade. This new transmitter had more channels, better range, and was more reliable than the old one. I then programmed the new receiver with the old servos, and everything worked perfectly.
I restrung the sails using fishing lure rope and re-tuned the sails. I created hatches from plastic sheet and used scotch tape to adhere to the painted epoxy decking. They work well and keep the water out. With all the components in place, I was ready to test sail the boat on Lake Victoria in Christchurch.
I had two separate test sails, and the boat performed really well. The first sail was in lighter winds and the boat was dry inside at the end. The second sail was more sporty and I did some good submarines and knock overs in the big gusts. A very small amount of water was in the hull but not enough to be a concern. A piece of sponge in the boat would be a good idea as protection. The jib foot is actually bigger than the main sail on this boat which gave the boat plenty of power. The rudder is also really large, which makes the boat very responsive and easy to control. The boat tacked well, but I had to sheet out just before the tack to spill the air, as the jib is so large it really stopped the boat heading to windward.
Overall, I am really happy with how my RS750 model yacht performed on the lake. It wasn't too challenging in the end to get it sailing once again. It's easy to overthink things and often it's good to simply dive in and tackle each issue if they arise. Overall a lot of fun and satisfaction. I enjoyed the process of taking the boat apart, inspecting each part, and refurbing it to make it better than ever. I am looking forward to many more hours of sailing my cool wee model yacht.
While I did get the boat sailing, functional and water tight it still looks a bit old and grimey. I might re-paint the hull and build a new rig at some point. Or build a new boat all together! Now there's an idea! Hmmm.
Happy sailing! Onwards.