[Score: 9/10] 29"/1200g Avanti Capable of 15mph and a runtime of 5mins Single Propellor (2 Blade X Type 35mm) Direct Drive to a OBL29/19-15M (2 Blade X Type) Powered by LiPoly (11.1v) 15Amp/h Batteries Controlled Through BLC-40M (25Amps) ESC - Comments: ARTR fast electric by Thunder Tiger. Deep vee powered by Ripper Brushless outrunner. Will reach 30mph+ when flat out. I replaced the radio that came with the boat with stick operated Futaba T2HR as I preferred "stick" to wheel for sailing fast boats. Initial problem was slight leak where stern tube passes through the transom but soon fixed it with epoxy. Electrics are in a box at the stern which is appears to be water resistant. Though not for a raw beginner, it is great for a second boat especially if someone is hoping to move on to a 6S . If not , it makes a good all rounder and is ideal for club fast electric racing and it performs well when doing tight turns. Boaty
Im not on here that much, so a little late picking this up. Are you talking about TT25 transducers like the ones Mrrcsound sell/ I suppose they all work the same, I've used these a lot, in planes mostly, and experimented with boats, so can offer some hands on advice. Firstly, you don't cut any holes to let sound out, as this isn't how they work. Its all about the vibrations. The centre ring is epoxied (that's the best way, they have to be permanent, but with some teasing they can be removed it required, rather than cyno) to the surface, which obviously needs to be flat. The thinner the material, the more sound, but its marginal, as the thinner you go, the less bass, or deeper tones. With planes, the best material by far is the epo foam, so when mounting into a ply or balsa plane they work best going to foam, then the ply, and the same will apply for a boat. 2-3mm is generally the optimum thickness. Remember, the area is going to vibrate, so use an area that can do this, the sides of a hull are ideal. The back of the transducers get hot, so don't cover the back, the heat has to dissipate and once secure, make sure the unit can move in and out, its easy to drip glue in the wrong place and the whole thing gets stuck, it wont vibrate now, so won't do the job. Also, its worth epoxying the transducer to 2mm foam, epo that the ready to fly planes works best, its close density, the stuff that packs white goods is poor as its a more open density and falls apart. Once you have this, you can move it around by just holding it against the hull to see where the best sound is. All this is relevant to the Mrrcsound transducers, I use a number of his sound units, so cant really comment on what you are using as I cant find that info on this thread (did a man read!) Here are a couple of my models to give you an idea👍 https://www.youtube.com/watch?v=jXFvrkDl7ow&t=207shttps://www.youtube.com/watch?v=_OITvPabFHY&t=165s so these are all Mrrcsound units, and both have two tt25 transducers either side ogf the hull and fuselage. With the Mrrcsound systems, you can use two tt25, if you want an additional two, then an aux amp is required hope that helps! Paul
Huson 24 RC sailboat wooden hull. I have a small fleet of these. They are extremely stable in high wind. Bought this one online in pretty good condition. Did a lot of smoothing on the epoxy coated hull. I use West Systems epoxy because it flows so well - like paint - and doesn’t stink. Finished the MD flag on the sails.
Boat lifting eyes As has been said by others the boat lifting eyes are a small detail but an important one, somehow when detailing gets in your head its difficult not to seek it out. Anyway, there are six eyes three on each side, which I presume, are for lifting the boat out of the water, unfortunately there isn’t any detail on size so it’s down to “builders eye”. I made the six in a batch, that’s to say I first made six identical pieces 10.5mm x 20.5mm x 2mm thick and drilled the hole in each then the six pieces fastened together with an M4 screw and then machined together to ensure uniformity and ease of production. I then skimmed them to final size 10 x 20 followed by milling the concave and convex radii on the top. I intend to sink the eye into the deck and secure using a brass pin sideways into the gunwhale stringers and epoxied into position. To ease fitting I made a small jig, which will allow a 2mm slot to be cut in the exact position on the deck along with a drilled hole at 90 degrees. Two small grub screws fasten the jig to the gunwale stringers while the slot and holes are machined. After all the slots had been prepared I then made all the foot rails that run along the edge of the deck from bow to stern, the first set I used the obeche supplied in the kit, however as they are in a place that could get knocked I decided to rework then in walnut. Finally I pre drilled all the foot rails ready for temporary pinning. Having all the components ready it is time to assemble with epoxy resin, using sparingly and making sure not to get any on the visible part of the brass lifting eyes and using pins to hold in position while curing. PS sorry about some of the picture quality but I didn't check them until after assembly
The sails need a little repair and Singers fabric glue really worked well. Still have fittings to add to main boom, but you get the idea. Thinking about how the plans rig the sheets. Will try it their way first, but looks like the servo is at a mechanical disadvantage. Plans say max wind is 10 mph! That’s way too low. Black booms are made from aluminum arrow with fittings made from brass sheet and copper wire. Reinforced keel to bulb connection with fiberglass cloth and West Systems epoxy.
ABC Hobbies put out this ABS hull kit with mostly ABS fittings. I bought one used on eBay and it had a broken bulb to keep connection. I bought another on eBay with the same problem. I roger one up and the normal tension broke the jib boom as it sat overnight. So the kit has design flaws. But the hull lines are beautiful- she’s a fine looking racer. Making aluminum beams and reinforcing bulb joint with 3/4 glass and epoxy.
Depends on the resin, NPJ. If it's epoxy you've bought, you need to weigh out 1/5th of the hardener to any amount of resin. Ergo...20 grams of resin, 4 grams of hardener. So get some electronic scales (very cheap and essential to the use of resin)put 20 grams in of resin and then, without touching the scales pour in drips of hardener till you have 24 or 25 grams showing on the scales. Don't go above that. Epoxy requires accuracy of measurement and endless mixing. Just mix and mix till you're fed up with it, then mix a bit more. Don't use large amounts as the heat from the curing of a large amount will set it off even quicker. Looking at your bottom picture, I see bubbles in the paint. Scrape them right off and see what's below. Probably soft wood, so scrape that out too and allow to dry thoroughly. Then in with the resin. If there's a bit of a dip, you can make your own filler by mixing fine sawdust with the resin into a peanut butter consistency and look and apply that to already wetted out surfaces. I used that on a full sized wooden canal boat. Worked a treat. When that's set, you can file it flat with a rasp and a second cut then wet'n'dry on a block to finish. Finally repaint and wax. But, as Doug says, you need to see if the water's getting in somewhere else like the shaft or rudder areas. Good luck, Martin
Maybe I should write one, eh, Colin? For the scratchbuilders among us. A treatise on brass bashing and woodwork. Nobody would be interested. I've just epoxied my Sea Hornet, which I'm modifying as a Chris Craft Custom Runabout. One cockpit, big hatch. Cost me 99p off ebay a few years ago. I just had to scrape all the old red paint off it as it wanted to fall off anyway! Then a huge rub down, a wipe with cellulose thinner and a coat of epoxy applied with a square of styrene sheet because I couldn't find an old credit card on the quick, just as good though. Next, rub down and 2 coats of cellulose primer surfacer, then the top coats. This one is to be one of the painted CCs. There were quite a few. But the deck will be veneered in the correct style and varnished. Martin
Have added reinforcing to the frame supporting the end of the shaft tubes, 3 pictures show dry fit. and once dry glue in shafts with epoxy resin, 3 pictures of fixed shaft tubes. Now looking at an extra part frame to support the three motor brushless out-runners.
Continuing with the cabin, trying to keep it light in weight. The sides and inner former's made up, started on the front windscreen's. Forgot the procedure about cutting the windows and then fitting the veneer, fitted the veneer and had to cut out the windows veneer and 3mm ply all glued up. Once the apertures were marked out, purposely drilled though from the veneer side just trying to avoid any splitting of the veneer, it worked. Fitted the front screens and reinforced the framework with 5 min epoxy, a quick sand down and all was well. Next item was the roof, as i wanted a light as possible upper works decided on .8mm ply, it looked and felt a little fragile, but once the Titebond glue was applyed all held down with elastic bands, also using 3 strips of 3/8" x 1/8" Obechie longitudinally down the top of the cabin roof to help stop ant edge "Barrelling" at formers. Regards Muddy.
Yep,I get Pinterest too, but they also mix in some of that cargo, too, which is a bit embarrassing if the Mrs. just walks in. On another boaty place people are saying the finish is too difficult! Epoxy and yacht varnish is all I ever used. Yes,if it's to be varnished it has to be well made, but so what? Does that mean all the tankers and lifeboats are badly made and covered in filler and paint? Anyway, thanks for your efforts, Doug. All encouragements to make woodies gratefully received. This is one I'm working on currently, when I can reach it off the top shelf! A Greavette Gent's racer, Double Time. Canadian graceful of Gravenhurst. Cheers, Martin
[Score: 8/10] 36"/6400g Adele Capable of 12mph and a runtime of 30mins Twin Propellors (2 Blade S Type 40mm) Direct Drive to a MACK 5045 (2 Blade S Type) Powered by NiMH (14.4v) 5Amp/h Batteries Controlled Through MACK 35 (35Amps) ESC - Comments: Model is from Dumas kit hull covered with 2 layers or 2 oz. fiberglass cloth and resin. Deck mahogany covered with 3/4 oz. cloth and resin, painted with klass Coat epoxy paints. Running lights and cabin light. Built with removable interchangeable bridge windscreen or windscreen with roof.
Doug: You’re right about halogen lights. They’re mentioned as halogen in one article but as mercury vapor in a few others. Over here mercury vapor lamps are used for highway & parking lot lights & they do have a soft, yellowish glow. Halogen would be quite harsh & hard on drivers’ eyes. Maybe a tug or similar boats would prefer mercury vapor lighting in deck areas because they’re quite effective at cutting through fog? MVs are a good choice for highways & parking areas for the same reasons, I guess. By the way, in your spreadsheet’s Notes column I noticed that you wrote “Clear” for the two deck light LEDs when in fact they’re yellow when operating. It shouldn’t make any difference to your calculations because you used the actual measured voltage in your calculations. Here’s a question. Suppose you were given a box containing dozens of clear & different colored LEDs, both the cheap tinted epoxy kind & the ones that have clear domes with different innards to give various colors. How do you tell what voltage they require? From what I’ve seen LEDs aren’t marked in any way with a tiny numbers or letters so how do you know their power requirements if they’re not in their original packaging? Are LED supply voltage requirements standardized? Thanks, The Eternal Questioner (AKA Pete)
Hi Pete, Yep, the colour of the LEDs can be determined by doping the diode chip with various elements. The early ones were either red or clear, so the colour was added in the epoxy dome around the chip. Cheap ones still are like that. Nowadays you can get LEDs that light different colours according to the voltage applied! For instance in those irritating shelf / vitrine light strings that rotate through a variety of colours all the time.😡 I have some that are red or green depending on which way round you apply the voltage! They are milky white when off. Useful for checking the operation and setup in the boat of brushed ESCs and motors, esp for multi-screw boats, and the output of switching circuits. Funny I always thought halogen lights were a hard white with a blue tint, like some car headlights. Cool on the Kelvin temp range. Yellow is more like the warm white light of a tungsten bulb to me. Yellow deck floodlights are more likely to be sodium lamps, like many street lamps. The measurements you sent me indicated that the switch on voltage (Vf) of the searchlight was 3V and all the others 2V. So I based my final calc on that. If any of your LEDs don't 'strike' with 150Ohm just reduce the resistor to 120 to give it a 'shove'😁 I don't expect that though. I have a box of 300 various LEDs and 1000 various resistors in front of me (and the mast from my Southampton tug😉) so will do some practical tests. Cheers, Doug 😎 BTW: I can strongly recommend that you buy a simple LED Tester, like one of these- https://www.ebay.com/bhp/led-tester I'll help you get the LEDs the right way round in your circuits and tell you how much current they need for a decent brightness, and at what voltage they will turn on! Only a few bucks and saves a lot of aggro. It'll also tell you what colour a 'clear or white' one will be when it turns on😊