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    Plan Sources
    Er... yes. I have also done a bit of research when drawing up the EeZeBilt PT boat. The US came late to the concept of light torpedo boats. The original doctrine, gathered from the old WW1 exploits of the MAS boats, was that these light boats would overcome capital ships by force of numbers and agility - typically in harbour defence scenarios where their lack of blue-water range was not an issue. Similarly, they could defend against prowling submarines. Since the US did not have any close maritime enemies, they did not consider light torpedo boats to be worth investing in. Strategy had moved on by WW2, and when the US finally considered them, with the 'Plywood Derby', their original raison d'etre had all but vanished. capital ships were surrounded by Torpedo Boat Destroyers, and radar meant that it would be suicide to consider approaching a 'big gun' enemy on the high seas. Nevertheless, the initial US PTB purchase specified armament for just this function - standard US Mk VIII tube-launched torpedos, smoke for concealment and 0.5 calibre
    machine
    guns for local/AA defence. This turned out to be almost completely useless in practice. The tactical doctrine makes engrossing reading: "...3401. Unsupported attack on enemy task force.-The plans for attacking an enemy convoy apply equally to attacking an enemy task force, the only material difference being that stiffer resistance may be expected and a great number of boats should normally be employed. 3402. Supported attacks in fleet action.-This type of attack has such a wide range of possibilities which depend on so many factors that it is not possible to recommend any general plan. Some of the possibilities, however, are listed below. (a) Night action with destroyer support where MTB's first attack the enemy screen, permitting destroyers to penetrate the screen and attack the - main body. (b) Night action with destroyer or light cruiser support where the DD's and CL's engage the screen, permitting MTB's to pierce the screen and attack the main body. (c) Day action where destroyers, aircraft and MTB's attack enemy main body simultaneously. MTB's launched from a carrier or operating from a fleet base. 3403. Attacks coordinated with aircraft.-Attacks by large numbers of motor torpedo boats and aircraft made simultaneously on enemy forces should be highly successful, as such attacks will present a great multiplicity of targets for enemy anti-aircraft and secondary batteries and will bring heavy striking power to bear on the enemy. The time of the attack will depend upon the motor torpedo boats, as aircraft can control their timing more readily. The aircraft attack may be a dive-bombing, strafing, or torpedo attack or any combination thereof. An aircraft torpedo attack, coordinated, should be made on opposite side from the MTB attack. A high altitude horizontal bombing attack will not divide the enemy's fire to the maximum extent, as he will not divert the use of his
    machine
    guns toward the bombers. In this type of attack all available motor torpedo boats should attack simultaneously...." !!! There are a number of propaganda stories during the early part of WW2 suggesting that PT boats were engaging and sinking Japanese cruisers. These all seem to be untrue, and circulated as 'morale boosters'. I can find few examples of a successful attack on a big ship - the strike on the light cruiser Abukuma by PT137 during the Battle of Surigao Strait (which was almost certainly a mistake!) is one notable example. The PT boats came into their own as shore harassing gunboats and inter-island supply interdiction once the initial Japanese advance halted, and that was when they began needing to add more guns. The Toku Daihatsu barges used for Japanese supply were almost immune to torpedoes, drawing only a foot or so, and were heavily armoured, so the 'Ma Deuces' were of limited use. Some early PT boats had a 20mm Oerlikon mounted on the stern. I have never seen one with twin Oerlikons mounted this way, though there might have been occasional one-offs. Invariably the armour plate on the gun was discarded for weight reasons. Single 20mm Oerlikons were also mounted on the front quarters, together with the distinctive 'horse-collar' M4 37mm cannon, initially from u/s Bell P-39 Airacobras, but later as a standard fitting. By 1945 they were adding 5" rockets... On the stern the boats were rapidly updated to carry a Bofors 40mm, which they could do when the heavy MkVIII torpedo tubes were replaced with light Mk XIII aircraft 'roll-off' torpedoes. A bit of a misnomer, this, as the torpedoes did not actually roll.... But I have never seen a PT Boat with a 35mm cannon on it. The radar fitting was one of three types: 1 - no radar 2 - SO dome 3 - SO-3 with rotating parabola. I wish there was a simple, cheap way to get a 1:48 Bofors gun. The EeZeBilt PT boats need a Bofors on the back, but I haven't managed to source one yet. And I suppose I should add torpedo tubes to provide accuracy across the whole PT range... Below is a picture of two EeZeBilt PT boats. The far one is an 1940 model with no radar mast and a single Oerlikon on the stern. It should really have tubes as well, of course. Note the position of the life-raft on the bow. The near one is a 1944 fit, with an M4 at the front and SO radar. The life-raft has moved back to the top of the chart cabin. It should really have a Bofors on the stern, and a small boat on the day cabin, but I haven't made these yet. And, of course, no PT Boat had varnished wooden planking. But I just thought that it looked nice... ๐Ÿค—
    24 days ago by DodgyGeezer
    Forum
    Plan Sources
    Hi DG, I'd be MOST interested to see what you consider to be the 'relevant plan'! So here is your 'Round to It' ๐Ÿ˜‰ I heartily agree with you regarding the portholes / glazed units! But as far as armament goes - Anything goes, especially for those operated in the Pacific theatre - which was the vast majority. Crews scrounged and used whatever they could get their hands on. The classic example is the 37mm Army Anti Tank gun JFK scrounged and fitted to PT109. To no avail; they were rammed and sunk the day after by the Japanese destroyer IJN Amagiri. If it worked it was introduced in the next production class. As far as your 'relevant plan' goes; I guess that depends on which boat of which class in which of 30 squadrons (RONS) of 80' ELCOS built at which stage of the war was taken as the basis of the plan. The early classes, up to about the 103 class (to which JFK's infamous boat belonged) had no radar at all. You are correct that there was a large radar pod on some PTB's. As built probably from the 200 class at the earliest. Earliest pics and references I can find indicate that the radar pods may have been first fitted to the 500 series. Highly likely that such such details were still secret and not available to Les & Co in the late 40s early 50s. I have seen some photos of PTBs with that odd 'button' on the mast top but haven't yet fathomed what it could be. Don't fit no radar antenna that I know of and it's way too small for the radar of the time anyway. Some earlier boats may have been retrofitted but not many. Most squadrons only had one or two boats fitted with radar at all (destroyers and upwards took precedence in the early days of radar, until centimetric and corresponding smaller antennas were introduced and could be mass produced) and most PTB skippers switched them off at night and lowered the mast anyway to reduce the risk of detection. The early classes also had no armament on the foredeck. As the official model of PT109 shows. Only the Carley Floats or some other form of liferaft. I also attach drawings from the USN Bureau Of Ships deck plan and profile drawings as designed and originally built. (Thanks for the pointer Maurice๐Ÿ‘). They and all subsequent classes were, consequent to operational experience esp. in the Pacific, rapidly fitted with a colourful assortment of single and twin barrel cannons fore and aft as well as single and /or twin 20mm Oerlikons midships and/or on the torpedo mounts - similar to British MTBs, e.g. Vosper. Later versions had all sorts of guns on the foredeck and a single 0.5"
    machine
    to port just forward of the cabin. so as far as a PTB model goes; Yer pays yer money and yer takes yer choice. You can fit a model with virtually anything less than a 3" QF/HA and probably be right for at least one boat somewhere at some time! In my archive I have dozens of photos of PTBs of various types and classes; as built, in operation, and as restored, if anyone needs 'em.๐Ÿ˜‰ Wrt the straight or front cabin; difficult to see what was intended in the Aerokits plan๐Ÿ˜ฎ I agree with you that the ELCOs had a cabin front slanted backward. The Huckins PTBs did have a straight cabin front. Not many were built and never saw war service being stationed mostly in Florida, Pearl Harbour and Midway and used for training. Maybe someone got their plans mixed up. Cheers and G'night, Doug ๐Ÿ˜Ž PS Have a look at Battleship Cove for lots of photos of the restored PT617. There you can see the later radar pod.๐Ÿ˜‰ "Armament The primary anti-ship armament was two to four Mark 8 torpedoes, which weighed 2,600 pounds (1,179 kg) and contained a 466-pound (211 kg) TNT warhead. These torpedoes were launched by Mark 18 21-inch (530 mm) steel torpedo tubes. Mark 8 torpedoes had a range of 16,000 yards (14,630 m) at 36 knots (67 km/h; 41 mph). These torpedoes and tubes were replaced in mid-1943 by four lightweight 22.5-inch-diameter (570 mm) Mark 13 torpedoes, which weighed 2,216 pounds (1,005 kg) and contained a 600-pound (270 kg) Torpex-filled warhead. These torpedoes were carried on lightweight Mark 1 roll-off style torpedo launching racks. The Mk13 torpedo had a range of 6,300 yards (5,800 m) and a speed of 33.5 knots (62.0 km/h; 38.6 mph). PT boats were also well armed with numerous automatic weapons. Common to all US PT boats were the two twin M2 .50 cal (12.7 mm)
    machine
    guns. Early PT boats (Elco PT20 through PT44) mounted Dewandre plexiglas-enclosed hydraulically operated rotating turrets.[12] Almost immediately after the attack on Pearl Harbor, the Dewandre turrets were replaced on the entire PT boat fleet with open ring twin mounts. The ring mount was designed by both Elco and Bell, and designated Mark 17 Twin 50 caliber aircraft mount.[13] Part of the Mark 17 Mod 1 and Mod 2 ring mount consisted of the Bell Mark 9 twin cradle.[14][15] Another automatic weapon commonly mounted on PT boats was the 20 mm Oerlikon cannon. On early series of boats, this cannon was mounted on the stern. Later in the war, several more of these 20 mm cannons were added amidships and on the forward deck. Forward of the chart house of some early Elco 77-foot (23 m) boats (PT20 through PT44) were twin .30 cal (7.62 mm) Lewis
    machine
    guns on pedestal mounts. Beginning in mid-1943, some boats were fitted with one or two .30 cal Browning
    machine
    guns on the forward torpedo racks on pedestal mounts. Occasionally, some front line PT boats received ad hoc up-fits at forward bases, where they mounted such weapons as 37mm aircraft cannons, rocket launchers, or mortars. When these weapons were found to be successful, they were incorporated onto the PT boats as original armament. One such field modification was made to Kennedy's PT-109, which was equipped with a single-shot Army M3 37mm anti-tank gun that her crew had commandeered; they removed the wheels and lashed it to 2x8 timbers placed on the bow only one night before she was lost. The larger punch of the 37mm round was desirable, but the crews looked for something that could fire faster than the single-shot army anti-tank weapon. Their answer was found in the 37mm Oldsmobile M4 aircraft automatic cannon cannibalized from crashed P-39 Airacobra fighter planes on Henderson Field, Guadalcanal. After having demonstrated its value on board PT boats, the M4 (and later M9) cannon was installed at the factory. The M4/M9 37mm auto cannon had a relatively high rate of fire (125 rounds per minute) and large magazine (30 rounds). These features made it highly desirable due to the PT boat's ever-increasing requirement for increased firepower to deal effectively with the Japanese Daihatsu-class barges, which were largely immune to torpedoes due to their shallow draft. By the war's end, most PTs had these weapons. The installation of larger-bore cannons culminated in the fitting of the 40mm Bofors gun[16] on the aft deck. Starting in mid-1943, the installation of this gun had an immediate positive effect on the firepower available from a PT boat. The Bofors cannon had a firing rate of 120 rounds/min (using 4-round clips) and had a range of 5,420 yards (4,960 m). This gun was served by a crew of 4 men, and was used against aircraft targets, as well as shore bombardment or enemy surface craft. Gunboats In the Solomon Islands in 1943, three 77-foot (23 m) PT boats, PT-59, PT-60, and PT-61, were converted into "PT gunboats" by stripping them of all original armament except the two twin .50 cal (12.7 mm) gun mounts, then adding two 40mm and four twin .50 cal (12.7 mm) mounts. Lieutenant Kennedy was the first commanding officer of PT-59 after its conversion. On 2 November 1943, PT-59 participated in the rescue of 40 to 50 Marines from Choiseul Island and a foundering landing craft (LCP(R)) which was under fire from Japanese soldiers on the beach.[17] Towards the end of the war, beginning in 1945, PTs received two eight-cell Mark 50 rocket launchers,[18] launching 5 in (130 mm) spin-stabilized flat trajectory Mark 7 and/or Mark 10 rockets[19] with a range of 11,000 yards (10,000 m). These 16 rockets plus 16 reloads gave them as much firepower as a destroyer's 5-inch (127 mm) guns. By war's end, the PT boat had more "firepower-per-ton" than any other vessel in the U.S. Navy. PT boats also commonly carried between two and eight U.S. Navy Mark 6 depth charges in roll-off racks. Sometimes they were used as a last-ditch weapon to deter pursuing destroyers. The depth charge could be set to go off at 100 feet (30 m), and by the time it exploded, the pursuing destroyer might be above it. Additionally, a few PT boats were equipped to carry naval mines launched from mine racks, but these were not commonly used. "
    24 days ago by RNinMunich
    Forum
    Look for a simple balsa build
    "........I have found that most old hand drawn plans are inaccurate......." I bow to your experience, of course! My rather more limited exposure to vintage model plans is that they are indeed inaccurate. Your points are all true, and on top of that wood and paper can shrink and warp over the years. I handled that on the initial EeZeBilts by providing a copy of the die-cut sheets as well as the 'improved' cutting lines, which were 'what I thought the designer meant'. It was still hard to be sure that I had got things right, because manual cutting from plans introduces more errors - but now that I have a cutting
    machine
    that source of errors should be minimised. I originally thought that PDF format was a good one to use for distribution, since it was meant to be a 'facsimile image' - but I didn't realise that people can set their printers up to do all sorts of default formatting, which can alter sizes...
    30 days ago by DodgyGeezer
    Blog
    Pulley blocks and Deck Rigging Screw Eyes
    Been away on holiday for a few weeks so not been doing much but back at it again - Pulley blocks The mast has a small pulley block on each end of the cross bar, but I wanted to have a go at making them so using some 0.5mm I marked out the profile and then bent the flat pieces into a channel this was followed by drilling an 8BA clearance hole through both sides. Next I
    machine
    d the centre pulley out of brass with a 2mm rad to suit the rope I will be using; I also did an extra round dummy pulley in steel to use as the template to file the radius on the frame and use as a guide for the width of the block. Using a smooth file I carefully filed the radius on each piece using the dummy pulley as a guide and trimmed the width, this was followed using wet and dry paper to finish. To fasten the blocks to the cross bar they need a screw fastening on the top, this was done by soldering an 8BA nut on the top. Finally the brass pulley wheel was secured in place with an 8BA nut and bolt, with a threaded stud in the top. Deck rigging screw eyes - can be bought, but again, I had to have a go, so first I ground a tool to form the end ball which would also part the piece off after it had been turned and threaded. The bar was turned down to the thread o/d and then using an 8BA die the diameter was threaded. I then used the form tool to produce the ball end, this worked OK but could be improved on as the final turned finish wasnโ€™t as good as Iโ€™d hoped for, but I donโ€™t have time to spend on this as I only wanted six eyes so the diameters will be finished with a small file and wet and dry. Turned pieces finished, next I set up a gang of slitting saws to mill the flats, holding each part in a split threaded clamp in the
    machine
    vice the flats were milled in parallel. Finally using the same clamp jig the ball was drilled with a 2mm hole again to suit the 2mm rope. Thereโ€™s some final dressing to do before the parts are clear lacquered.
    1 month ago by mturpin013
    Forum
    CNC boat kits...?
    ".......I am on a bitof a learning curve at the moment........" A few lessons I learned: 1 - Get a good, solid base-board which isn't warped. The local timber yard may have off-cuts of 3/4" ply. You will want to assemble the mechanics on a proper base, and it helps to have it available first. You will want to paint it anyway, so it will need time to dry. 2 - Get a dial indicator. An easy way to check for precision in assembly is to attach a dial indicator to the end of the Z axis and run it over the base board. It's good for other fault-finding and calibration as well. There are cheap ones on Ebay. 3 - Plan out all the wiring. I put my limit switches in as an afterthought, and found that I had wires which couldn't go in the places I wanted them to go. 4 - Wiring loom control. Consider Drag Chains, Heat-shrink tubing and Braiding. All items are very cheap from Ebay. If you don't put the wiring in at assembly you won't be able to put it in later once everything is connected up... 5 - If you use a drag chain for the USB connection, you will either have to make sure that it's wide enough to take a USB plug passing through it, or cut the plug off, pass it through and re-solder it afterwards. If you do the latter, note that the shielding in a USB cable is aluminium, and won't solder. So you will need to use a connector plug which has a physical connection to the shielding, because interference can ba a problem on these
    machine
    s....
    1 month ago by DodgyGeezer
    Forum
    CNC boat kits...?
    Oak or Mahogany for stable signs, I do plan on fitting limit switches at first anyway. I am on a bitof a learning curve at the moment. Once I have the
    machine
    up and running I will no doubt get the hang of it. Good cheap screw supplier.. https://www.gwr-fasteners.co.uk/m3-socket-cup-point-grub-screws---high-tensile-17166-p.asp
    1 month ago by Nickthesteam
    Forum
    CNC boat kits...?
    My plan is to trace PDF files into DSM and output as DXF, or work up my own drawings. I have DXF to G code so I guess I could deal with your files. When finished, my OX will be used for all sorts, cutting aluminium is a must, Daughter has demanded name plaques for her horses stable, she reckons her horsey pals will pay for nice carved name plaques so who am I to argue! ply and balsa cutting will be essential and possibly light brass sheet, hence my first choice of the 900 Watt DeWalt router. I may well end up with an arsenal of spindles/routers and eventually a laser head. I am using the CNC shield for now but the intention is to use a Rumba board, a versatile Arduino mega 2560 based board with loads of output options more commonly used on 3D printers, I have upgraded 2 of my printers with them already. Like 3D printers, the options for modifying/tweaking are endless. I will be fitting endstops, but I may use TMC 2130 drivers, which do not need endstops, as soon as they detect a substancial increase in current they switch off. My Mk3 Prusa has them, certainly reduces the ammount of wiring! I have a notion to draw up some plans for a series of warship boats at rc able size, ie, 47ft Whaler, Skimming Dish FML Cheverton Launch etc, interesting boats but rarely seen actually on the water as working models. I have a milling
    machine
    so a plentiful supply of milling cutters is available for a range of jobs.
    1 month ago by Nickthesteam
    Forum
    CNC boat kits...?
    Hi. This
    machine
    is called the Ox, a full set of plates, anodised in black, is on sale at Oozenest at half price, I am building it bit by bit as I do not have funds for a kit. All parts are sourced in the UK, either from Oozenest, plates, extrusion some bolts and other Ox specific parts, Arduino Uno and CNC shield, the rest, Nema 23s, Toshiba motor drivers, bolts, some extrusions, 30 wheels, spacers etc from WE Do 3D Printing in Sheffield. Control will be via Arduino Uno and CNC shield, with Toshiba 5 amp drivers on a 24 volt PSU. This
    machine
    can be made as big as you want just by increasing the length of the extrusions, which consist of 20 x 80, 20 x 60, and 20 x 40 V slot. Mine will have a footprint of 750mm x 550mm, which will give me a build area of around 380mm x 650mm. Big enough for me, I have very little space and I am going to have to sell a couple of 3D printers to make room. I will be using GRBL firmware, Designspark Mechanical for design, DXF2Gcode for converting and Universal G code sender to cut. I don't anticipate needing a bigger
    machine
    as I cannot lift big models any more so 600 mm long will do me. I have not thought about work holding and my designs, If I manage to get ant sorted that work, will be there for anyone to use.I have not fully mastered the art of CAD yet, I learned Tech Drawing on a drawing board with T square and compass. This weekend will be a laugh as I am going to get the electrics sorted, I have mastered Marlin, used in 3D printing, and I have been laboring on the misapprehension that CNC would be the same, so it's teach meself GRBL time! https://ooznest.co.uk/product/ox-cnc-aluminium-plates/ https://shop.wedo3dprinting.com/ Please note, I have nothing to do with the suppliers I have linked to other than as a satisfied customer...
    1 month ago by Nickthesteam
    Forum
    CNC boat kits...?
    Hi, I am in the process of building an Openbuilds Ox
    machine
    . So far I have built the gantry and Z axis. The drivers for the Nema 23 motors should arrive on Saturday so I can spend the bank holiday weekend fiddling about with the electrics. I will use a Dewalt 900Watt router for the spindle so there will be enough power to cut aluminium sheet. I have been using 3D printers tobuild a minesweeper with great success so a CNC router will add to mt arsenal...
    1 month ago by Nickthesteam
    Forum
    CNC boat kits...?
    Having successfully used the
    machine
    to make the workholding support for the wood sheets, I started on the final leg - getting the
    machine
    to actually produce parts for a model boat. It's just going to be used for EeZeBilt balsa parts initially, until I understand a bit more about cutting tools and feed rates. I'm not using a 'professional' spindle motor (which can cost well north of ยฃ100), but just an old model boat motor with a cheap Chinese chuck and milling head. You can see a couple of examples in the pictures below. The first material I tried to cut was cardboard. I wanted something really weak, because the cutting tools are very narrow, and I did not know how much sideways force they would take. Turned out fine, though. Further pictures show the first attempt at cutting balsa sheet, a whole sheet of 1/8 balsa being cut, and a couple of parts which have just been cut. Points to make: 1 - you need a high RPM from the cutting motor if you want a fast feed speed. Boat motors work, but a high speed brushless would be better. As it is the edges of the balsa are a bit ragged... 2 - Probably the best way to keep all the parts in the balsa sheet is not to use tabs, but just to cut 90% of the way through. I left about 5 thou on the balsa part, which meant it stayed in place but could easily be pushed out... 3 - you need a soft surface under the balsa sheet in case you do cut deeper by mistake. I thought of felt but that gets caught up in the blade too easily. You could use another balsa sheet, but I used a bit of Correx. Depron would be fine... So there we are. I have now cut a complete kit out of balsa and will start to make it up. I can recommend this
    machine
    if you want to just sit and have a beer while all the hard work of cutting parts is done for you...!
    1 month ago by DodgyGeezer
    Blog
    Detailing the cabin โ€“ Part 2. The Roof Rails.
    Some hardwood dowel is supplied in the Vintage Model Works kit for the handrails that would look perfectly acceptable for most builders but as Iโ€™m going a bit overboard with the detailing of my boat I chose to fabricate mine differently to look a little more authentic. This involved selecting some obeche stripwood of suitable dimensions and carefully measuring and marking out the positions of the supporting legs and the spacing between them. Again I used some โ€˜photos of the NMM model as a guide for this. Fortunately I had previously treated myself to a vertical stand accessory for my Dremmel drill and I used this as a milling
    machine
    with the addition of a suitably sized sanding drum and an improvised โ€˜fenceโ€™ attached to the base of the stand. After making a test piece I also chose to attach a vacuum cleaner hose to the stand to extract the dust as the process generates quite a lot! Milling out the recesses in the obeche strip was a remarkably quick process but the subsequent hand finishing using abrasive paper glued around a dowel and some abrasive pads took a great deal longer to achieve the final profiles. I was very pleased with the final result and so I applied several coats of Teak stain before hand drilling a 2mm hole in each of the supporting legs to take a plasticard rod which was superglued in place. These form fixing spigots that will enable me to easily fix the rails through the roof without using epoxy or superglue on the roof surface but on the underside of the roof instead. The legs at each end of the handrails were drilled to take 1mm rods as the legs are a bit smaller. The rails were then laid out on the cabin roof and with the aid of some masking tape the position of each plasticard rod was marked and then the drilling centres marked with an indent through the tape onto the roof. The fixing holes were all hand drilled through the roof and the handrails pushed into place before being secured with a drop of superglue on the underside. When set the excess plastic rod was cut flush with the roof panel. The finished result is very pleasing ๐Ÿ˜€ as seen in the last pic along with a sneak preview of the searchlight.
    2 months ago by robbob
    Forum
    CNC boat kits...?
    While it helps to be accurate, the final trimming of the work holder is done by the
    machine
    itself. Here I am cutting the edges of the holder so that a sheet of 4" balsa will be neatly held. That's about 1.6mm wider than a 100mm sheet, so I will need a packing strip if I use the metric sizes. It's surprising how precise these
    machine
    s are - I'm moving the cutter in by 0.1mm each pass, but it can move in much smaller steps - one microstep is 6.25 microns, which is about 2.5 ten thousandths of an inch. The balsa will be held between some raised sides made of hard balsa, so that they can be cut easily by the
    machine
    if I get a command wrong and move the cutter out of the work area. I expect to put a 2mm felt layer below so that the cutter will have something soft if it goes completely through the workpiece.
    2 months ago by DodgyGeezer
    Forum
    CNC boat kits...?
    Once the
    machine
    is set up, we run into the two classic workshop requirements - tooling and work-holding. We hardly need a powerful spindle or Dremel for cutting balsa, which is what I am going to start with. I am going to use an old brushed boat motor with a small chuck added. But I need an easy way to hold the workpiece. Here I am making up an experimental vacuum holder. It's sized to take a 4" x 36" sheet of balsa. I hope to slip a blank sheet in, run the
    machine
    and take out the equivalent of a die-cut kit sheet an hour later. Note the requirement for everything to be massive and rigid, so that items can be held exactly in a repeatable position without movement while the cutting forces are applied....
    2 months ago by DodgyGeezer
    Blog
    new sails
    the other half has been a busy bee with her sewing
    machine
    so today i set about fully rigging her
    6 months ago by jacko
    Response
    Dressed overall for launch party back in June 2018
    Very pretty ๐Ÿ‘ "Splice the mainbrace chaps" ๐Ÿ˜‹ Is that a converted Singer treadle sewing
    machine
    table I see before me? Cheers, Doug ๐Ÿ˜Ž
    7 months ago by RNinMunich
    Blog
    Gina 2 Billing Boats Fish Cutter - Restoration & Conversion
    As promised (or threatened?๐Ÿ˜) stage two of the hull work and thoughts on motorisation. The hull was sprayed with two coats of grey primer/filler. Pic1. As usual this showed up the remaining imperfections (pics 2 & 3), but I'm not going to worry about them until I've got prop shaft tube and rudder stock sorted out and permanently fitted ๐Ÿ˜‰ After my attempts to make and thread a 3mm prop shaft went awry Martin (Westway the Mechanicals Master๐Ÿ‘) stepped in and made me a decent one complete with a bushed stuffing tube ๐Ÿ‘ Vielen Dank Meister๐Ÿ˜Š I did however manage to make a 4mm to 3mm reducer so that I could fit a Rabeosch 35mm prop as seen in pics 2 & 3. The tube and shaft from Martin, arrived Saturday an' he only made it on Monday๐Ÿ˜Š, have been dry fitted so that I can start setting up the gears, necessary to bring the drive down to the prop shaft fitted very low down in the hull, and motor mount. Pic 4. Motorisation: (Remember folks - this kit was designed and built as a static model!) I want to use the old 1950s Taycol Target motor which my Dad originally fitted in the Sea Scout which I have renovated and upgraded to work forward and reverse with a standard ESC. See Build blog 'Sea Scout - Jessica' Many of you will know that the Taycol motors were field coil motors, meaning that they have no permanent magnet around the rotor coil, and thus reversing the battery connections to the brushes had no effect on the direction of rotation, as this simply reversed the magnetic fields of both stator and rotor coils๐Ÿค” To counteract this so that the motor could be used in both forward and reverse with a conventional brushed ESC I modified the motor slightly (separated the two coils) and built a simple converter board to connect it to the ESC. Again see the Sea Scout blog for the details of the conversion. Basically; once the field coil and brush-gear (rotor coil) have been separated a simple diode bridge can be used to apply the output of the ESC to the motor. This enables the reversal of EITHER field OR rotor coil polarity, depending on how you connect the converter to the motor. Thus reversing the direction of rotation of the motor. Beneficial side effect is that the diodes also suppress the commutator sparking๐Ÿ˜Š In my case, with the Taycol Target, I also cleaned, flattened and polished the commutator. Thus significantly reducing the potential for spark generation in the first place! A peculiarity of the Taycol motors is that they all use metal brushes, pressed phosphor bronze strip, so they need oiling! DO NOT oil conventional brushed motors with carbon brushes unless the brushes are exchangeable or you want to have to buy a new motor!!!!! Pics 5 & 6 show the proposed position of the Taycol in Gina 2 and pic 7 the prototype converter board I knocked up to test the motor, together with a Graupner Navy V30R Marine Brushed ESC. Details and results in the Sea Scout blog, including video of the sparks and oscilloscope pics of the drive waveforms before and after conversion! The latter showing the spark suppression effect of the converter๐Ÿ˜Š Some samples attached - last 3 pics. Pic 8 pic shows a more compact version of the converter, one of a few types I'm doing for Martin's various Taycols as a trade for the prop shaft he made for me and some useful material he sent. Thanks mate๐Ÿ‘ Next steps will be 1) mounting the gears correctly on the shafts, requiring the manufacture of a 3/32" to 4mm adaptor and a 1/8" to 4mm adaptor, and keying them to the shafts - Hooray for mini milling
    machine
    s ๐Ÿ˜‰ 2) manufacturing bushed end plates to hold the gears in place, 3) fitting the motor mounting platform. I'll probably borrow from my experiences of real shipbuilding and do this as a suspended 'false floor', i.e. mounted on stiff springs to enable adjustments to optimise the gearing mesh! On real naval ships this is done to improve shock resistance and to minimise engine noise / vibration conduction to the hull, thus significantly reducing the acoustic signature of the ship. Not that I'm tooo worried about being torpedoed ๐Ÿ˜ Worth a try๐Ÿ˜‰ Pic 9 shows the cleaned up and renovated Taycol Target motor. Pic 10 shows the drive waveform complete with sparks before modification.๐Ÿค” Pic 11 the cleaned 'forward' waveform with the converter board. Pic 12 the cleaned 'reverse' waveform, no suppression capacitors needed ๐Ÿ˜‰ More soon folks, Cheers, Doug ๐Ÿ˜Ž PS Along the way a new keel was fitted as can be seen in pics 1 to 3. The original builder had 'buried' the keel in the hull planking! ๐Ÿ˜ฒ
    10 months ago by RNinMunich
    Forum
    Prop Shaft Grease
    Overall I would go for the silicone clear grease. it isn't actually clear but greyish appearance en mass but seems clear when spread thinly.I repeat that WD40 does not contain any silicone and never has done. it is not a lubricant but a release fluid and a moisture dispersant. it works well in conjunction with a light oil. Sewing
    machine
    oil is ideal. Very low drag factor and good corrosion resistance.3 in 1 as good second choice for the mixture. Believe me from experience
    1 year ago by onetenor
    Blog
    water, paint, copper
    The gun deck isn't modeled. I was building a model intended to sail in open water and didn't want to deal with open gun ports, hatches, etc. After glassing the hull, she got beams for the spar deck installed. 3/4" x 3/4", they're probably a bit more than was needed. Tubes were installed for 5/16" stainless threaded rods that would hold her external ballast on. The forward one will be disguised as her galley stovepipe, the aft one is hidden under the cabin skylight. The ballast is a 2" i.d. PVC pipe about 4 feet long, filled with lead bird-shot, and weighing some 42 pounds. With that much done, I took her to the creek to see her float, but I forgot the rods. A few days later I took her out again, remembering the rods, and put her lower masts in her. Now baptized, I applied the moldings and trim on her stern, and built up her enclosed head. Her gunport were molded in resin in the closed position with the guns clamped in the openings and a tampion in the muzzles. These were epoxied into gunports cut from the outer layer of glass and wood battens, leaving the matting in place as a backer. Then she got some paint, mainly because I was getting tired of her looking like a barkless log. The bottom was painted with copper paint, but three rolls of 1/2" wide peel-n-stick tape had just arrived and I started into coppering her bottom right off. Copper plates are nailed on with copper nails with counter-sunk heads through pre-punched holes in the copper sheets. The are FLAT with with a little hollow where they're driven in just beyond flush with the surface. They are NOT round headed nor look like rivets as so many models insist are doing. I pressed an impression of the nails into the face of each plate. installing them pushes this dent back out and leaves a little circle that looks as it should. It took about a week to do one side, and I took a break to make the tops for the lower masts, then continued onto coppering the other side. it was bright and beautiful when finished, but it wouldn't stay that way. Copper doesn't turn green when submerged, any copper coin will show you it turns brown. I wanted her bottom to brown somewhat, but not too much, and I figured to let that happen naturally. When it got where I wanted it, I'd clear-coat it to lock it in. Two yards of Dupont Supplex cloth was ordered to make her sails. This is the stuff SC&H used on their square-rigger kits and it's great for making sails. Being a nylon, you cut it with a hot-knife, and use a pointed tip in a soldering iron to make grommets. I drew on the panel seams with a .03 marker as even the finest stitching is over scale even at 1:36. Top-cloths, corner reinforces, reef bands, etc, are all cut from the same cloth and glued on with fabric adhesive. The only sewing was of the bolt-ropes. These are done by hand much the way real ones are - I've sewn a few miles of real bolt ropes in my time. There's really no substitute for this if you want a functional scale appearing sail. A
    machine
    can't sew it properly, in the right position, or securely.
    2 years ago by Jerry Todd
    Directory
    (Tug Boat) TBC
    Scratch built loosely based on the St Chanute ,made from recycled wood the winch is made from parts of an old sewing
    machine
    the mast is copper pipe and an artists paint brush handle the rails are split pins with 1.6welding rod soldered the rigging is cord from a venetian blind dyed using indian ink ,the only bought items were the propeller ,anchors ,paint and glue (ESC: scratch build) (5/10)
    2 years ago by marky
    Forum
    Oil Sump for Gearbox?
    Dave Looks to be well made. I would ask Maritime as they may have experience of using the unit. it rather looks like the gears are carried on brass/Bronze shafts with similar bearings mounted in the ali side plates. Whatever you use you will need to keep any grit etc out of the mechanism. A simple removable plasticard cover would help. A spot of light
    machine
    oil (not 3-in-one) on each bearing before each sail would be my guess. Sewing
    machine
    and model train shops sell light oils. But do ask the supplier. Cheers Dave
    2 years ago by Dave M
    Response
    s.b. Vigilant
    That look great, I saw boats like that at a model engineering show earlier this year, I can't remember the name of where it was, but it was at some race course Anyway I was very Impressed with the boats on display, the sails colours look cool lol ๐Ÿ˜€ Can I ask how long did it take to plan/build, also did you use a sewing
    machine
    on the sails? Thanks for reading & the time you spend on it ๐Ÿ˜Š
    4 years ago by Damon
    Forum
    diesel help
    Mate , Peter Dimberline wrote to me to offer some help from a colonial in suggestions for you , has somebody taken the backplate off and re bolted it back without the crank pin engaging in the rotor hole in the fuel induction pin hole ? maybe the fuel needle has been replaced without a taper in the end of the needle and the pin being manufactured in the motor is a non genuine needle replacement ? is there any ether in the fuel mix as the ether may have been evaporated off in storage ? maybe the needle hole in the needle air carby throat valve outer tube is glugged up over storage time and the engine seems to run on the prime only , ( soak motor in ether or acetone or methylated spirits overnight to de glug old castor residue then drain shake dry remove partly the backplate just enough for solvent to dribble all out then retighten backplate screws , then put some light type oil sewing
    machine
    type light oil drops in holes of motor and finger turn over to get oil in the innards etc , the old racers tended to have the needle open from about 2 turns out to near 2 !/2 turns out to be at the sort of general running setting , maybe the needle was tooooooo far open ? maybe the induction hole in the carby is not in line to the throat into the rear crankcase induction so that fuel air is drawn horizontally into the chamber ( hard to describe but easy to mis assemble if someone previously has readjusted and misaligned the induction flow) ? sorry for so many ideas to you but as regards fuel level, I have had engines suck up fuel from the bottom pipe inlet easily an inch below the needle level , but even a half inch uphill suck up is ok even if the tank is say 2 inches thick as you get a sort of pressure head effect which is rich to lean in run . A better idea is to fit/build in a "chicken hopper effect" in the main tank to give an EVEN fuel flow rate of delivery to the carby. Old Team racers did this successfully and it is good for diesels. All the best Lyle.
    7 years ago by Lyle
    Response
    riavarama
    HI Gregg, No I'm not sure whether there will be enough bite on these rudders (never gave it a though if I'm honest!) all I can say in my defence is that I copied them direct of off the plan that I have, hoping wherever the plan came from got it right, it will be a case of suck it and see, if not I have provision to change the size. Thank you for your interest. Well I had a bit of a result today I bought 6 sheets of .6mm x 12" x 48" teak veneer for ยฃ10. An art shop just wanted to get rid of it, and they have more in stock. it has all come from the same tree, so the patterns match as well. I also bought the blue leather for the upholstery for ยฃ10. Just got to persuade my wife to do the stitching, I could do it myself but I'm only allowed to service her sewing
    machine
    ! Well tomorrow looks as though no sailing or flying so I shall get on with sorting out the hull bottom first skinning, the hull has been rub down and the first thing to do is hoover the workshop out, there is dust everywhere!! Brian
    7 years ago by sharpy1071
    Forum
    fireboat cof g
    It's been interesting to read the various views about lubrication. On some of my boats I've used vaseline mixed into a light froth with sewing
    machine
    oil, it seems much less prone than grease to drag and 'caking up' away from the surfaces it is supposed to lubricate and protect. has anybody else heard of or tried this ?
    10 years ago by thelegos
    Forum
    fireboat cof g
    Good advice Peter. Regarding the outer shaft, if the steel inner was bent it is possible that the outer has also been damaged. Replacing the shaft and bearings will only be successful if everything lines up and the shaft can rotate freely with no tight spots. The shafts pictured showing oiling tubes would be ideal - but as Peter advises use a light oil. When you have set it up the running sound should be similar to a well oiled sewing
    machine
    . Any rattles, squeaks or vibration should be identified and removed. There are different varieties of stainless steel, 303 grade will rust in time so try for 316 (marine grade) it is much more resilient to rust.
    10 years ago by Dave M


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