Cookies used in this website are gluten free, wheat free and dairy free. By using this website you agree to our use of cookies. More Info
Guest
Login Below
Join Us On Social Media!
   
Get The Model Boats App!
Apple App Store
Android app on Google Play


Help Support This Website
£
or enter custom amount

(Non Contributor)

Help support this free
website and donate.



£285 a year is needed to keep the website and apps online. Please consider donating £5 or more to help towards these fees.
All donations are securely managed through PayPal. Amounts donated are not published online.

Many thanks for your kind support.

Model Boats Website Team


Donation History
October 2018: 5 people
September 2018: 13 people
August 2018: 5 people
July 2018: 8 people
June 2018: 8 people
May 2018: 7 people
April 2018: 24 people
March 2018: 13 people
February 2018: 8 people
January 2018: 9 people


Unique Visitors This Month

Website Members

Terms and Conditions
Privacy Policy
Advertising
Contact


Model Boats Website
Active Users (13)
Login or Register
To Remove This Ad

Login or Register
To Remove This Ad
>> Home > Tags > shaft diameter

shaft diameter
shaft diameter
prop shaft
propshaft
propshaft alignment
shaft diameter
Rudders and Propellers by RNinMunich Fleet Admiral!   Posted: 4 days ago
BTW; I copied your above massive text block into a document file and split it up into paragraphs so I could see where you're at! My conclusion: so far so good BUT! You made the one classic mistake of many model boat / ship builders 🤔 You continued the prop shaft tube right back to the propeller and hence you had to make oversize struts to support them. This is fundamental wrong and creates unnecessary work.😉 On real ships, including the Schnellboote, the so called 'stuffing tube' is JUST THAT, it 'stuffs' the shaft through the hull and includes stuffing glands to prevent the ingress of sea water. Outside the hull ONLY the rotating shaft itself continues on through the bearing in the support strut and to the prop. See attached pics of my HMS Belfast as an example. There was actually no reason for you to make oversize strut bearings, simply bushes to match your prop SHAFT not the tube would have been correct. Inside the real ship there is also NO TUBE, only bearings at suitable intervals. They look like gigantic versions of the big ends in your car. Imagine on really big ships, carriers, container ships, bulk tankers etc, with shaft diameters of 1metre or so how big the 'tube' would be, how much weight that would add and how difficult it would be to service and maintain! I've often noticed in posts here that folk confuse shaft and tube, often referring to the whole assembly as 'the shaft'. For convenience we modellers use prop tubes, who wants to fiddle about making a row of internal shaft bearings no one will ever see and will most likely never be really concentric? The downside is that continuing this 'convenience' outside the hull is wrong, adds weight and detracts from the scale appearance of the model. 😭 OK, it's 3am here now so - orf me 'obby 'orse and up (in my case down!) the wooden stairs to Bedfordshire, G'night all, cheers, Doug😎 Re shaft length: What fits fits, what don't don't! Such a question is like asking 'How long is a piece of string?'! If all three motors abreast won't fit you have to decide if the central motor should / will fit fore or aft of the outer motors. Then measure / adjust the shaft length accordingly. Before you start fitting the centre motor check what length shafts are commercially available and adjust your motor fit to suit. Otherwise make your own shafts and tubes to fit as required, as I've started doing cos I got fed up with 'standard sizes' wot don' wanna fit my ship. 🤔 G'night All, cheers, Doug 😎

Rudders and Propellers by teejay Commander   Posted: 12 days ago
Hi all for the second blog report on the schnellboot I am going to go over the rudder a propeller shaft assembly in more detail. The first stage was to make the rudders which were made of brass ,and having taken note of what has been said about the increase in size needed for the kit by other members I have increased the size of the rudders by 50% so that they have more effect and hopefully the boat will be more agile .I fitted 3mm treaded rod on to the rudder and in a 4mm flanged tube to reinforce the brass rod. The second stage was to make and fit 5mm flanged tube in the location for the rudders in the boat, these were made to be above the water line and will be sealed in place to reduce the possibility of leaks. These were fitted to a rudder platform inside the boat which was fitted to the kit moulding for the rubbing strip that runs the length on the boat and secured by making resin blocks which were fitted with computer extension nuts. which were then superglue in place to secure the rudder platform. The rudders were then fitted in place and held in position with the tiller collars which were made from 8mm rod and fitted the tiller arms and locked in place with 3mm computer screws and ni-lock nuts, a connecting plate was then fitted to connect the three tillers together, I also fitted rubberised washers to seal the rudder tubes. The third stage was to make the propeller supports. The centre support was a direct copy of the kit part made of brass and fitted to the kit with a plate and screws (this plate and the rudder plate were made from galvanised steel) and will sealed with resin after the I test the boat for leaks. The port and starboard supports were made by taking the kit parts and cutting them in have along the joint line or mould seam this gave me a template ,which I used to make cross-section segments but I did alter the template by increasing the boss diameter to 10mm and extending the support legs so that the finished support could be fitted through the hull (the picture of these show the mk1 version where I forgot to allow for the 4mm prop shaft which has a 6mm tube) any way the boss of these segments were drilled out with a 7mm drill and a length of 7mm brass tube fitted through the boss to assemble the segments, all of which were coated in soldering flux at this stage of the assembly which were riveted at both ends to hold it all together during soldering, after soldering the supports were then filed to the size and shape to resemble the kit parts as close as possible and fitted to the hull using a superglue and talcum powder mix and then I cast resin around the extensions to secure the prop supports in place. The fourth stage is the propeller shaft housing for the centre propeller housing I place a brass rod in a plastic straw and place in position in hull and using resin I sealed the hull with the rod in place this gave me a pilot hole for the centre prop shaft after I removed the brass rod. For the port and starboard shafts I used the kit parts which had hole place when assembled, this when I reinforced the housings ,the centre housing I glue 2mm of plasticard on each side and for the port and starboard I made a brass tube shroud which covered the housings which left gaps between the kit part and the brass which was filled by casting resin in the gap this increased the diameter to 10 mm so that there were little chance of breaking throw with the drill and finished these off by fill-in the outside with body filler and sanded to shape and finish . I then drilled through the pilot hole in the housings using very long extended drills and a wheel brace ( if I had use a power drill the heat would have melted the plastic of the kit and may have caused problems) I drill the shaft housings out 6mm them filed them out with 6mm file so that I could insert a length of 6mm brass tube. After all this was done I fitted a flanged bush made from 7mm tube and 2mm brass plate turned to 11mm to the ends or the propeller shaft housings. And now it is time I must ask for some help could anyone advise me on the length of propeller shafts, I know I can use a 300mm shaft for the centre shaft, but port and starboard will have to be longer. and I also need advice on selecting the motors, I want to use 4mm prop shaft with 35mm propellers. Any opinions welcome.

VOSPER 46" Crash Tender by RNinMunich Fleet Admiral!   Posted: 12 days ago
Actually 4 pole , "Graupner HPD 2920-4000 High-end brushless motor Particularly suitable for: MiniMono, MiniHydro, MiniCats, MiniHydroplanes, aircraft with wingspan up to 1 m, off-road and on-road 1:12 Features ?Special CNC-machined housing for maximum heat dissipation ?High-efficiency 4-pole 12-slot brushless motor ?High-performance rotor with Kevlar reinforcement ?High-purity copper coils for optimised conductivity ?Extremely strong sintered neodymium magnets ?Intense torque at low weight Specification Operating voltage range : 4,2-16,8 V No-load speed: 29600 U/min All-up weight, approx. : 90 g Free shaft length: 10 mm Recommended controller: Navy V75 G7257 Output : 650 W Number of poles: 4 Permissible motor direction : R und L Nominal voltage: 7,4 V Case length: 30 mm Shaft diameter: 4 mm Case diameter: 29 mm Revolutions/Volt: 4000 " Taken from one Google, first response at Cornwall Models Boats!😉 Note. 650W, Nominal voltage 7.4V. No wonder it's a bit quick on 11.1V 😲 Cheers, Doug 😎

Taycol Supemarine Resurrection by RNinMunich Fleet Admiral!   Posted: 1 month ago
Evenin' Colin, Thanks for the offer. I'm going to use some stuff the Martin sent me, called Chrodite apparently, although I can't find any description or reference to Chrodite anywhere! Looks like brass with an extra ration of tin. Supposedly harder wearing. Anyway, stator and frame spacers etc are now finished.👍 So after feeding the inner man I'll start measuring up for the bushes and see what I can do about tidying up the drive shafts. Have just sorted out a 'Live Centre' for the mini lathe which should help. I want to hide the bushes inside the original Paxolin cards and the external end plates which contain the felt oiling pad. So ball races are out of the question unfortunately; too large diameter and too thick 🤔 Needle roller bearings would be nice, but I ain't got none that small😭 (Nah, admit it Doug you ain't got none at all, they're way too expensive😭) Amused myself today polishing up all the brass nuts and bolts! Confucius he say "Polishing nuts - very painful" 😁 Weather should be good for spraying tomorrow so I might fire up the compressor and give my PTB a blast of Pacific Green. 😊 Cheers All, Doug 😎 BTW: where are the pics of your Avanti? Harbour posts without pics are pretty dead 🤔 Cheers, Doug 😎 Oops! This doesn't belong here!🤔

54" long Cervia tug. by tysonyoung Petty Officer   Posted: 2 months ago
My Cervia was ready built. I have replaced the Electric motor with a large servo motor (Brushed) .Direct drive and being heavy helps with ballasting. lead acid gel cells are power source. Motor rated voltage24 v but run it on 12v . low rev high torque no load current 1 amp. Shaft diameter 0.5 in. Gives some idea of power out. Being servo motor (ex computer drive 30 years old) well balanced no vibration. Photo near shore shows power of motor.

Help with a 4BA prop by Westquay Fleet Admiral!   Posted: 2 months ago
Hi all, just measure the shaft in my Chris-Craft and blowed if it ain't 4BA thread on a 3.5mm shaft. Can't change it as it's well buried in the hull, but I don't have any props with a 4BA thread. Does anyone have any spare 2 or three blade props of about 30-35mm diameter with a 4BA thread. I'm sure somebody must have one tucked away somewhere and I could always do a bit of modelmaking by way of a swappsy. Cheers, Martin

HMS Sabre, Scimitar-class preceded by Archer-Class by CB90 Fleet Admiral!   Posted: 2 months ago
[Score: 5/10] 26"/1400g HMS Sabre, Scimitar-class preceded by Archer-Class Capable of 12mph and a runtime of 15mins Single Propellor (3 Blade 35mm) Direct Drive Powered by LiPoly (7.4v) 3Amp/h Batteries Controlled Through China 60A (30Amps) ESC - Comments: Just finish this little boat, need to have its first trial on the water to measure current draw and perhaps modify the prop size. Make sure water cooling works, and the thing steers ok, as rudder is off set. and may have to be move into the prop wash. The Motor 3650 4Poles 3060KV Brushless RC Motor for 1/10 RC Car Boat 1. 4Poles design, high torque and high efficiency. The overall efficiency exceed 90 percent. 2. Low heat production, long lifetime, strong overload protection and it can function 95% of its features without any heat sink appliance. 3. High quality materials adopted: high intense aluminum alloy anodizing shell , front and back cover , high-performance temperature-resistant magnetic steel and imported high-speed bearing. Specifications: Model: XTI-3650/4.5D Dimension: 50 * 36mm KV(RPM/V): 3060KV Poles: 4 Max Power: 1300W Max Voltage: 19V Max Amps: 68A Shaft Diameter: 3.2mm Shaft Length: 15mm Connector: 5.0mm Banana Connector. The real boat Builders: Halmatic Operators:  Royal Navy Preceded by: Archer class In commission: 2003 – Active: 2 General characteristics Type: Patrol boat Displacement: 24 tonnes (24 long tons) Length: 16 m (52 ft 6 in) Beam: 3.1 m (10 ft 2 in) Draught: 1.2 m (3 ft 11 in) Propulsion: 2 × MAN 2480LXE diesels, 2 shafts Speed: 32 knots (37 mph; 59 km/h) Range: 260 nm (480 km) at 19 kn (35 km/h) Complement: 5 (1 officer, 4 ratings) Sensors and processing systems: Racal-Decca Bridge-master 360, I band navigation radar Armament: 2 × General purpose machine guns (stern-mounted)

Chinese props by Westquay Fleet Admiral!   Posted: 2 months ago
Just received a prop for my outboard motor from China as I couldn't find one for dog drive and the right shaft diameter over here. It wasn't the cheapest, but ye Gods, somebody has seriously specced up this baby. It is superb, light as a feather, completely CNC machined, sharp as a razor. Couldn't be happier with it for an ebay purchase. Now, with brushless and prop, I suppose I will have to get the boat finished! Cheers, Martin

Cheap motor for a quick fit, but what prop gents?... by RNinMunich Fleet Admiral!   Posted: 2 months ago
OK, found one, 'discontinued product' 🤔 Seems Tower pro only make gas engines these days. https://hobbyking.com/en_us/towerpro-brushless-outrunner-240... Specs "TP 2408-21 The most widely used towerpro motor available today. the 2408-21T is often used in GWS (means Grand Wing System, USA apparently!) upgrades. Paired with just an 18A besc, this motor is an excellent and cheap way to upgrade small planes to brushless. An RD1047, RD9070 or 8040 size propeller are the best choice, with the RD9070 and 8040 giving the best thrust and amp draw balance. For 2-3 Li-Poly Cells (7.2-12.6V) 31 mm diameter x 62 mm length Maximum current: 13A Weight: 50.2 grams / 1.77 oz Comes with stick mount plastic frame Firewall mount capable Comes with two prop nuts and one washer 3mm shaft diameter 10mm x 10mm stick mount Kv: 1750 9 Stator Poles, 12 Magnets" So it's OK for a 3S LiPo, which will give about 19.400rpm OFF LOAD. Max current 13A ON LOAD. No way of finding the other little one without at least a hint🤔 Looks like an Outrunner plane motor as well. Suck it and see! Probably similar specs to the Tower motor. The two brushed ESCs should be good for your Taycols as none of them should take much more than 10A or so. Use 15A fuses, as I have already fitted to your converter boards.😉 Bon chance mon ami, Cheers, Doug 😎 Re GWS; https://www.google.com/search?q=GWS+models&client=firefox-b&... Pic is a typical GWS small plane, called 'Slow Stick'. If I had one I would name it 'Spindle-shanks' 😁

Painted outside by CB90 Fleet Admiral!   Posted: 2 months ago
Finish painting and adding some stickers, and a couple of pictures of the real thing. Fitted Motor in a water cooled jacket and motor mount. The motor is a 3650 and is rated as 3060kv Max Power: 1300W Max Voltage: 19V Max Amps: 68A Shaft Diameter: 3.2mm Shaft Length: 15mm Connector: 5.0mm Banana Connector Net Weight: 181g Servo fitted sideways via rubber bellows to external rudder fixed to transom.

20th Scale ELCO 80ft PT boat part 5 by CB90 Fleet Admiral!   Posted: 3 months ago
After some calculations I find I need to extend the reinforcing for the port & starboard shafts forward towards the bow. Created some wooden guides when drilling the prop-shaft holes and glued them in position temporarily, as you make expect the drill needs to be rather long, so I made one out of an old brass shaft basically sharpening it so it could cut wood. Next job will be to cut out for integrated shaft support brackets (2mm wide and minimum of 35mm long slot) and the tube shafts are 8.5mm in diameter.

ELCO 80ft PT boat Jumping the gun by CB90 Fleet Admiral!   Posted: 3 months ago
Yes, jumped the gun and brought the motors. Already have 3 light weight Aluminium prop-shafts that I intend to use: Tube Length:25CM/9.84inch Tube diameter:8.5mm/0.33inch Shaft diameter:4mm/0.15inch Stainless steel Weight:67 g The Motors will run on 3s -11.1v Three of these (one as spare): High Performance 2808 1400KV 14 Poles Brushless Motor Max Watt: 350W Voltage range: 7-15V Max amps: 35A No load: 1.2A One of these as centre motor or my swap for spare of above: High Performance 2826 900KV 14 Poles Brushless Motor KV(RPM/Volt): 900KV Max Watt: 1000W Voltage range: 7-18V Max amps: 60A no load : 2.2A

Brushless outboard... by Westquay Fleet Admiral!   Posted: 3 months ago
As Doug suggests, a new topic for this. The Motor is a 2845 of 2600Kv. I have no idea what the shaft diameter is so may have an adaptor to turn there. The guys what makes the rules for 152VO say 2 or 3 S, but there is a formula that takes in S number, prop size and Kv and it should all add up to some magic figure which escapes me. If anyone's interested, I'll look it up. The website, a very good one, is in German and really doesn't translate well! Martin

Lifeboat plans by Westquay Fleet Admiral!   Posted: 3 months ago
Doug, the outboards are made to take a 28mm brushless. There's an angled pre-drilled plate comes with it, to which I assume a 28mm brushless screws. They tend to use 2S LiPos on their boats with 23-2800KV, so about 18,5oo revs or a bit more. Can a brushed motor do that? I have a speed 400 from an aeroplane. Not sure what the shaft diameter is. I want it to go well, although, no I won't be racing it. As far as I know nobody does 152VO in England. I just need to fit a usable motor that I can build the Godiva casing round it. I don't want to HAVE to spend 30 quid on a motor, when I have one here, but I don't know what the performance would be. Martin

Brushless motor selection by canabus Fleet Admiral!   Posted: 4 months ago
Hi robhenry What volt battery are you running at present ?? 12 or 24 volts. If 24 volts those motors spec at 24,000rpm. Power is 511 Watts on 24 volts. 24,000 divide by 14.8(4S Lipo batteries) equal 1612 kv. So the closest motor would be 1700kv, eg water cooled 3660SL-1700kv which has a 5mm shaft and 44mm diameter with a length of 60mm( from Hobbyking). Power rated at 1800 Watts on 6S, so it would be lower than that. But if you are running 12 volts on the Graupner motor it would be about half the rpms. These brushless motors are far more powerful so check out the specs on the motors you are looking at !!! Canabus