Response

Re: Torro RTR - LCM3

Never too old....as long as you have two thumbs, can hold a scalpel steady enough, and the inclination then all is good....stay afloat.

4 years ago by POGray

Forum

Hints and Tips.

Fine Detale Sander. Hi guys another little tip. If you have some old scalpel s that are blunt and you normally replace them with new ones, how about gluing a small piece of fine sand paper or wet/dry paper on to them. Then trim to the shape of the . It then becomes a nice thin sander that will get into those little awkward places.(especially if the is a long pointed one) Martin555.

4 years ago by Martin555

Forum

Accurate hole drilling

I know the feeling Ken. We often pop in there, usually buy something like Titebond or s for my Stanley Slim Knife ( The one with which I spear my foot). I'm hankering after a scroll saw to use on the work my 1960's magnetal fret saw from Hobbies won't handle. Alice has promised me more space once the shed is finished, so I'll probably get one then. Trouble is, with my medical problems and spending nearly every day at the moment in the...........hospital, it's not getting finished. All the best, Nerys

5 years ago by Nerys

Forum

Are there fairies.

Silly boy Martin, I did a similar thing with a scrap machine, but I used a jigsaw and it worked perfectly well for about 3 years. Setting the foot about 25thou above the workpiece it cut wood, sheet brass, sheet steel and aluminium. I've now got a bandsaw, picked up at local auction for a tenner. Cheers Colin.

5 years ago by Colin H

Response

Re: HELP needed on a hull.

Back to the request! My method for hatch as l like to disguise them. After screwing down the cover planks are pressed in ( tight fit ). I use rubber from split wiper s, & window seal.depending what l have. Of course a square will be easier. You should also get or make the punt.I did post a tutorial here a while back. Note only one oar, always sculled.

5 years ago by hammer

Forum

Workshop

Perfect hobby machines, I'm in the wrong country!. We used to have a lot of small new lathes for sale here in machinery outfits for around $1200 NZ but I haven't seen any for a while. I could do with a small lathe especially for boat stuff. We had a Triumph 2000 (lathe not car) and a Bridgeport mill and all the gear when I was in the site services dept in the big woodworking co I worked for. I made good use of those, plus in my workshop I had 2 German RS2000 tool grinding machines which were great for touching up all your router bits and saw/ planer s etc and a Chinese mill which I reco'd when the other guys didn't want to use it. Made my sons cars' frame and running gear (all 10 speed bike gears modified etc', -everything adjustable for growth) while I was there . Sure great if you have the gear!

5 years ago by jbkiwi

Response

Re: Motor Questions and thanks

Hi Cash, "I’m thinking that on direct drive I’ll be pushing this motor on 7.2 volts." There are "zillions" of 550 motors! Are there any serial / type numbers printed on the can? Have a look for yours here- https://www.google.com/search?q=dc+motor+rs-550&client=firefox-b-d&tbm=isch&source=iu&ictx=1&fir=wFpgdoQt9jPTMM%253A%252Ckw1G-Gtwxi95qM%252C_&vet=1&usg=AI4_-kSsTy1M371uDM2ZqZw_SuKQqv1VnA&sa=X&ved=2ahUKEwiqjczzhv7jAhVJYlAKHQqbC5oQ9QEwAHoECAgQBg#imgrc=PXxe5eKmgAEAPM:&vet=1 I don't think any of them will have the slightest problem with 7.2V and a prop (3 I presume?) up to 40mm or so. That type of ship isn't exactly a sprinter anyway 😉 Cheers, Doug 😎

5 years ago by RNinMunich

Forum

Magnetic motors

Hi Colin Now that is interesting as it has set my mind off on a different thought path, model azipods. But that is a different story for a different thread another day. While it will do the same job, its design is different in that we are looking at putting the motor around the prop s as opposed to motor in the centre. Thus mimicking the real world that RR and Voith market solutions for with their Tunnel Thrusters. I am guessing Doug is correct with his workshop capabilities and cost observations on the tunnel drive. Maybe one day when the kit is available....... Who knows what is possible?

5 years ago by ikseno99

Forum

Magnetic motors

Err!! Not my intention. Clone the motor design and wind a waterproof one then add the scimitar s into the centre of the brushless, and you would have the tunnel drive??

5 years ago by ikseno99

Forum

46'' RAF Crash Tender

with regard to lights, white at top of mast just use an led that fits in the mast and run the wires inside. I ditched the white metal mast, its weak, and a bit of a mess imo. Its not too difficult to make one from some cheap brass. green and red nav lights (I used the tips from pens to replicate the shapes of the mountings) blue front of wheelhouse under the mast stand (see number 72 on attachment) white search light much talk of the white stern light! but no mention in any of the Vosper paperwork, (but it is on one of the pictures) Then if you want to illuminate inside the cabins etc, I used pygmy bulbs to give the yellow look It now all depends on the level of detail you want. I made my mast to fold as per the original, I read that the unusual shape of the mast legs was due to the fact they used plane propeller s (RAF boat don't forget) they do resemble this, but its a nice story!

5 years ago by pmdevlin

Blog

The Instrument Panel.

I decided that an instrument panel would enhance the appearance of the ‘Steering Wheel’ power switch so I made up a panel to go around the switch onto which I could put some dials and a throttle control. In my previous blog update I discounted using the very nice but pricey BECC transfers and looked for an alternative, Doug (RNinMunich) kindly sent me a .pdf of some instruments but the resolution was very poor when printed out. So after a bit of Googling I found a picture of some real commercially made instruments that was quite high resolution, and importantly, printed very nicely even when scaled down to the sizes I needed. I used a premium glossy photo paper in my Canon Pixma printer for this. The panel was made from some 2.0mm ply from the scrap box with the edges bevelled for neatness and after two coats of Teak stain they were ready to have the dials applied. The dials were cut out from the printed sheet as best as possible with a new scalpel , not easy I might add, as they are so small that you can’t really make a continuous circular cut so it was a case of nibbling round the edges until it was an acceptable shape. That was a test for my old eyes 🤓 I can tell you. The edges of the dials were blackened with a black ‘Sharpie’ pen before sticking down onto the panel with a light smear of canopy glue. The throttle control is just an offcut of Obeche carved and shaped and with a short piece of styrene tube and a pin head for the lever, painted in gunmetal grey it doesn’t look too bad. I used a small white ball headed pin in the final assembly. The instrument panel was given two coats of satin lacquer to protect the dials before the throttle control was stuck down and then the whole piece glued down onto the battery cover, and I also painted the aluminium switch panel black so it was less conspicuous through the slot. I had arranged the height of the wheel so that the battery cover can only be removed with the switch on the off position as a safety consideration. Also there’s room inside the battery box for a low voltage alarm attached to the battery balance connector too. Viewed through the cabin window the instrument panel looks quite acceptable and it all helps to disguise the purpose of the steering wheel and the switch can be accessed easily through the sliding cabin window without removing the cabin. Quite pleased with that 😁

5 years ago by robbob

Forum

Magnetic motors

No sweat Ed 😉 ALL you have to do is take a brushless Inrunner apart, build the stator coils into an aerofoil section nozzle ring (same cross section as an aircraft wing) with the "underside of the wing" on the inside of the nozzle and the blunt end up front,* then JUST graft some neodymium magnets onto the ends of your prop s 😮 balance and polish. Then just install your nozzles where you would normally fit the rudders. Use a 360° servo for steering control. Easy peasy 😁 Interested to see who does it first😁 Cheers, Doug 😎 * Effect of this is to increase the water pressure inside the ring and decrease it on the outside. Thus improving the efficiency of the prop / impeller.

5 years ago by RNinMunich

Forum

Propeller direction.

An opportunity for an essay! Props work like a screw. It should be fairly easy to see how the prop 'screws' through the water - this video may help: https://youtu.be/GpklBS3s7iU?t=4 Far harder is working out what 'left hand' and 'right hand' may mean for model boat props. This is because the US and Europe (essentially Germany) have (or had) opposite standards, and so 'left' for the US means 'right' for Europe! The UK generally goes with the US - but you need to be aware of the issue. It is because the same prop rotates clockwise or anticlockwise depending on whether you look at a boat from the bow or the stern, and different companies adopted different ways of viewing their props.... From PropShop: "..Where previously we only made these in left-hand rotation, all new steam props come in both left and right-hand. Please note that propeller rotation is based on the British and American standard (viewing the boat from the stern) which is the opposite to that in Germany..." There is quite a lot of discussion of this annoying feature on the boards - see here, for instance: https://www.rcgroups.com/forums/showthread.php?1993791-Prop-Rotation-North-America-vs-Europe Most of the explanations of how to determine left or right hand props seem to me to be ambiguous and liable to mislead. It would be much better to talk about clockwise or anti-clockwise rotation viewed from the bow or stern, but left and right seem to be accepted describers. The best description I know is this, and even it can be improved a bit: https://www.harbormodels.com/proprotation.html Let us try to improve it (with apologies to Harbour Models): 1 - place the prop on a flat surface with the driven end lowest. The driven end will either have a screw hole or dog groove in it. The un-driven end may taper to a point, or simply be flat. 2 - rotate the prop so that one is in the 12 o'clock position. It does not matter which this is. 3 - look at the 12 o'clock only. The will have 2 edges, a left and a right edge. Which of these edges is lower - nearer to the supporting flat surface? 4 - if the left edge is lower, the prop needs to rotate anti-clockwise to go forwards when viewing it from on the supporting surface from above. If the right edge is lower, the needs to rotate clockwise for forwards motion. 5 - For US and UK companies, the anti-clockwise prop above is 'Left', and the other one 'Right'. This seems to be becoming a world standard, but several companies may still use the opposite notation, and of course older props will be marked with whatever standard applied when they were made. To avoid confusion, describe prop rotation by including direction of travel, rotation and direction of view in your statement. Thus 'This prop drives forwards when it rotates clockwise viewed from the stern'. Avoid talking about left or right hand.

5 years ago by DodgyGeezer

Response

Re: STARLET

Markie, the makers of saw s are "starret"

5 years ago by Wingcoax

Forum

CNC boat kits...?

".....I have the files to make a dragknife that works with a stanley , it is 3D printed and has a steel shaft mounted in ball bearings. Some commercial ones are over 250 quid!....." Sounds like a lot of work. Here is the one I got - I see the price has gone up to £4.49! This comprises an aluminium housing with a magnetised steel shaft in it mounted on ball bearings, and 15 precision knife s in carbide - different angles for different thicknesses of material. I have mounted it in a Delrin collar, and it looks as if it will perform perfectly. Lot less time and trouble (and cost) than making your own... https://www.ebay.co.uk/itm/15pcs-30-45-60-Degree-For-Roland-Cricut-Plotter-Vinyl-Cutter--Holder/131906788936?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2749.l2649 I would love to get the plans I drew 'checked out' by a third party who has a precision cutter. My early ones are rather poor - I think I am getting better, but I am still likely to make mistakes. The PT boat would be a good choice - not too much wood and it makes up quite nicely. Of course you would still need to make the fittings - but direction is given on the web site. The figures shown below are cheap Chinese railway figures - about £2 for a dozen - modded and painted up...

5 years ago by DodgyGeezer

Forum

CNC boat kits...?

I have the files to make a dragknife that works with a stanley , it is 3D printed and has a steel shaft mounted in ball bearings. Some commercial ones are over 250 quid! Do you have files for the eze built torpedo boat? I could give that a go....

5 years ago by Nickthesteam

Forum

Hintsand tips - Decals made easy

"....It's a lot easier and cheaper then buying a vinyl cutter and learning how to use it. It might not cost much more than a pack of decal paper...." I can't report on the 'learning how to use it' part, since I haven't started, but having a CNC machine means that you can add all sorts of tools onto the cutting end. At the moment I just use a small router to cut balsa - I would use a bigger one or a laser to cut ply - and I have just bought a 'swiveling knife' set to cut vinyl. Cost of a mount and 15 s - £4.37. Should let me cut any size or shape character out of vinyl (or anything else) sheet...

5 years ago by DodgyGeezer

Blog

New drive Train and Oiler

Most of this actually took place last August / July! Regular readers may have seen that when Dad built this boat in the 60s he put a Taycol Target field motor in it. About 25 years ago I put a Decaperm and 'modern' transistor ESC in her to provide forward and reverse. Performance was sedate to say the least. I have since modified the Taycol (see below) so it can be run forward and reverse and decided to put it in an ancient Billings Boats Danish fish cutter (Gina) that I inherited from an Aunt. The cutter is badly in need of renovation (see pic 1) and the Taycol will be more suited to her performance requirement! On advice from Canabus in Hobart I obtained a Propdrive 2830 1000kV brushless motor, appropriate ESC and a 35mm 3 prop from Raboesch. Pic 2 shows the old and new motors. Next step was to trial fit new motor mount, coupling and prop. Pics 3 &4. While doing this it became obvious that a new shaft was in order, as mentioned in last update. Soooo, - appropriate stainless steel rod, thrust washers and set ring were acquired and back to the workshop. After cutting to length to accommodate the new coupling type a 3mm thread was cut a the prop end. At the inboard end I milled recesses for the grub screws in the set ring and the coupling, pics 5 - 7. I don't like to just file(or even mill) flats for the screws cos they have a tendency to slip and work loose😡 Trial fitted the new shaft and found I'd boobed a bit with the measurements and need extra thrust washers to make up the difference. 😲 Pic 8. No sweat, they came in a pack of 50 anyway😊 You can also see in this pic that I decided to fit an oiler pipe while everything was in bits anyway.😉 To solder it on in a cramped space without setting the boat on fire 😡 I packed a wet rag underneath and used a gas Kitchen Torch! Known as a 'Gas Gourmet Burner'. Yep, those handy little gas torches like your Missus uses to melt the brown sugar on her Crème Brûlée!! So do I, delicious 😜😉 The torches are not expensive, small, very handy, refillable with lighter gas and can be adjusted to a very small hot flame. ideal for this job. See pics 9 & 10. Pic 11 shows the new motor & mount, shaft and coupling all trial fitted after using a brass alignment tool I quickly made up on the lathe. Pic also shows the trial electrical installation after cleaning up the 'machinery compartment' a little and painting with silver Hammerite. A Quickrun BL ESC is sitting in the bottom in one of the trays my Dad originally fitted for the 2 wet cell (very wet!) 6V lead acid batteries. The home made board on the left carries the battery and ESC connectors, main ON/OFF switch with LED, fuse holder with a 20A fuse and a green LED which tells me if the fuse is blown! Stuck on the walls (OK Bulkheads!) with so called Servo Tape are a 6 ch Turnigy iA6 2.4Gig RX and the arming switch for the ESC. Battery compartment is sized to fit 2S and 3S hard case LiPos. For trials I can fit my Wattmeter forward of the switchboard and splice it into the battery supply using Tamiya connectors. Might change these to XT60s later if current drain is more than 12 to 15A. All for now, all this was pulled out again preparatory to cosmetics on the hull, decks, cabin roof and walls inside and out. But that's another chapter so, 'Tune in next week, same time same channel when once again it's time for 'WHAT DO YOU MEAN BUCK RODGERS IS APPROACHING!? 😁 Or 'The Saga of the Cabin Roof' 😉 Cheers Doug 😎 BTW: After drilling the shaft tube for the oiler pipe I flushed it out with light machine oil (pumped in from a big syringe) and shoved a few pipe cleaners through (rotating them on the way) to remove any remaining drill swarf!!

6 years ago by RNinMunich

Forum

Prop size and speed

Agreed Martin, one thing at a time! BUT: Stuart; I believe we are discussing your 24" Commander here. In which case your results mirror mine with my 24" Sea Scout. Except that my prop shaft did not bind!!😉 It was also reluctant to plane with a 2S LiPo (7.4V nominal) but went very well and planed easily with a 3S (11.1V nominal). I also was using 4000mAH batteries. I published my results using various batteries here in the Media - Video section. Go to the Media Gallery and search for Sea Scout. So, I would leave the motor and prop alone and (after fixing the prop shaft!!!) try a 3S battery. I'm sure you will be satisfied 👍 Prop technology is complex as Martin said, our old friend Bernoulli raises his head for instance🤔 But, essentially bigger is better for more speed or same speed with lower shaft revolutions when applied to real size ships. BUT 2: with our electric powered models bigger props often simply increase the load on the motor causing it to draw more current for a fractional increase in boat speed if any. In essence props with fewer s are inherently more efficient as you hinted. Minimum being 2 of course 🙄 Two rs are popular with the Fast Electric guys for that reason. I don't do speedboats, I'm a scale guy and my maxim is; If the real vessel had an XYZ screw then so will my model! Summary; first fix the propshaft; lubrication, alignment with motor shaft, ensure a few thou of clearance between prop hub / locknut and the end of the shaft tube. Preferably with a thrust washer in between. Second, fit a 3S battery preferably crosswise above the C of G of the boat. As you can see in the pic of my Sea Scout 'engine room' in your Commander thread. For those with a mathematical mind, undying curiosity and an afternoon to spare I attach a paper on the Principles of Ship Propulsion from MAN, the supplier of small to huge diesels to probably a majority of ships (commercial and naval) built today. You should find Chapter 2: Propeller Propulsion particularly illuminating! Happy reading 😉 Just remember the paper deals with real ships and real water, we have scale ships but not scale water🤔 Basic dynamics still apply though. Cheers, Doug 😎

5 years ago by RNinMunich

Forum

Prop size and speed

Hi doug and anyone out there.... you mentioned you tried 2 & 3 prop what was your conclusion?? did the boat go faster or did it accelerated faster or is there advantage 2 s are for speed,? and 3 are for power? i have a dumas CC commander 36 inch long. wondering if i should us 3 prop. comes with a 2 d and going to run twin motors. also should i revers one of the motors, for better control??? thank you samc

5 years ago by samc

Forum

Prop size and speed

Caution Martin! A larger prop may only increase the current drawn by the motor without increasing speed. in some cases less is more! Rule of thumb is prop diameter not significantly greater than the diameter of the motor. I think the solution here may well lie in the type of prop and/or the battery. Stuart hasn't revealed which battery he is using. The motor and the boat are the same size as my Sea Scout which does pretty well with a 3 35mm prop with pitch approx 1.4. Running off a 3S LiPo. Motor is a Propdrive 1kV ~30mm diameter. In the past I tried a 35 and a 40mm two (S type) prop with sedate results compared with the 3 . Shaft alignment and lubrication also plays an important role of course. Cheer, Doug 😎 PS "The pitch of the s also determine the amount of distance per rotation that the boat will travel but that also has its limitations. This subject can get extremely complex." You are so right Martin! The wood that you are putting a screw into stays put. Water doesn't🤔 So, amongst other things, you would have to know the 'Slip Ratio' of your prop design!!

5 years ago by RNinMunich

Forum

Prop size and speed

Hi, Regarding motor speed/prop size. There are so many factors to take in to consideration on this subject. Also the fact that most model boats that you see go a lot faster than there proper scale speed. After looking at your last video I would say that you have it about right, if you were to make it go faster firstly do you have the room to fit a larger propeller? If not then the only course of action you have left is the motor size or pitch. If you change the motor you could end up with the motor rotating so fast that the propeller will be next to useless. (If you imagine a wood screw going in to wood the distance per rotation) The pitch of the s also determin the amount of distance per rotation that the boat will travel but that also has its limitations. This subject can get extremely complex. If your model is sitting at it's proper waterline then removing weight will not be the answer either. Without getting technical I would personally try a different pitch first then assuming I had the room try a combination of prop size and pitch. I don't know if this has helped. Martin.

5 years ago by Martin555

Forum

Tamar Lifeboat propellers

Hi Want to change to brass propellers on Model Slipway 1/16 Tamar Lifeboat. Lost one of the original plastic propeller supplied in kit , and looking at Roboesch 40mm brass as replacements . Not sure whether to go for 3 or 4 s and type A or C Type props. Good speed from the supplied props with kit running with brushless Tornado 3536 1050kv on 3s lipo. Any recommendations of what to go for would be helpful. Thanks

5 years ago by alan50

Blog

HMS Cottesmore in 1/48 scale.

Hi Guys, As I mentioned the Bridge in my last log I thought that I would cover the Radar on top of the Bridge. As you may have gathered I quite like working with plastic card, so making the Radar was just a case of gluing some layers of card together and shaping. To make the Radar turn I modified a standard servo to continually rotate and by adjusting the pot slightly I managed to get it to rotate clockwise one full rotation at a speed of approximately two seconds. It seemed to be the correct speed, as I have seen on many models the Radars spin like a helicopters rotor s and to me that is not correct. The video is 'hidden' in the Invalid File. To view- Click on the Invalid image, Then click the Download button, white arrow on blue background at top left. Windows (App?) offers the choice of View or Save. View with Media Player or equivalent. Martin

5 years ago by Martin555

Response

Re: HMS BRAVE BORDERER

Bit of torque roll there Doug, skipper might need moving to the starboard seat. Skipper hasn't been on the Schnapps by any chance? -re failure to give way (starboard rule) and collision with tubby yellow boat. A smaller prop might lessen the roll, plus trim tab, and as you mentioned, spray rails. Sounded like the tunefull scream of a 28mm out-runner? I had one in my 36"Maiami with a 25mm 3 which did a similar speed to your Scout (with no torque roll) but I temporarily put it back to brushed as I couldn't stand the noise. Also it was useless for on board videos for obvious reasons. Smaller props plus high rev capability give much nicer slow speed control, John B

5 years ago by jbkiwi

Forum

Hints & Tips

Would it be possible to start a topic on hints & tips in building? For instance I struggled for years with filler application , and when going through my old artist type oil paints etc to pass on to my kids , came across some old W&N palette knives. They work a treat from the very small to very large applications. Had bought a cheap set before leaving UK from one of those outlets that pop up from around Christmas, dug that one out and the broad and angled s work well for the large applications. The flexible heads push the filler in very well and practically no wastage.

5 years ago by redpmg

Blog

Manufacturing of Paddles

I started with the paddles. Main reason was that I was not sure the final product would work. I ordered all the brass parts using eBay and google. Templates were photo copied from the drawing (paddle frames) and stuck to 1/32 brass sheet. Centre punched all the points that needed to be drilled. Holes drilled used a jewellers saw to cut out the frames and finish off using files. I had not done anything like this before but patience was need to replace all the broken s. I note that the saw came with 120 s. I then made all the paddles, the spider gear, etc using soft soldering technique. The wheels were then assembled and tested. small adjustments had to be made with a file as some of the paddles were fouling each other. Disassembled them and painted them using car spray paint. I was quite pleased with the paddles so could start thinking about the tug hull. ,

5 years ago by Hillro