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[tonyH]

Just to add to Derek's note about alignment between the motor and the propshaft, I don't know whether you've seen one of these but they are rather useful and if you then mount the motor in place with something like silicone sealant, rather than screws, you can just let it set while the alignment tool is in place and then just replace it with the u/j.
https://www.modelboatbits.com/UNIVERSAL-ALIGNMENT-TOOL

[Allen A]

My thanks to all for the comments and tips, I have info that the 'dog-bone' type of connector works well at angles and in fact doing some work on my 1/6 jeep last night I noticed that the main connector there for the 4WD is a semi 'dog-bone' type and well offset too and that does run well I have to admit, so I may leave well enough alone for now, or at least until the boat has had its first outing, not to say 'shake down cruise' before making any changes  ..   


Well .. its as finished as I think I want to take it, just the waterline painting to neaten up and I may well add some small deck dressings as and when I can find them, life jackets, rope coils etc etc .. but for now I have added the crew, painted one of them to look like an Officer, (chose him as he had some binocs. in his hand)  ..  what    ... and also used a little bit of imagination in placing the other crew members, so at the risk of 'soliciting feedback' here she is ...

[frogman3]

HI Aleen well she looks good love the crew  figs as these bring a model to life an it dont look static well done an i hope your first shake down criuse goes better than my tiger's did
lovely model
atb
chrisb

[Allen A]

Thanks ..  soooo ... as a prelude to actually sailing her under power, I thought I would do the next (or first) best thing and do a float test ... and she seems to sit with an even keel and trim, also in getting a smaller battery and being able to place it to the rear of the motor instead of in front as the other larger battery was, it has bought the nose up a little to a more realistic stance I think .... I don't really know from boats but it looks right to me ..??

[Allen A]

Been a while but still here and still working on things ... I got the one in this topic where I want it and it runs well, made a couple of changes in that I hid the on/off switch and added lights where I could, mast, searchlight nav. lights etc .. thing being I got another one that had been started, not overly so but it was all there and had twin motors/rudders whereas the original had been somewhat botched to a single motor and rudder.
Anyway completed it but have a problem, whereas it will run in fwd and reverse on its stand, it wont on water, runs forward OK, but also runs fwd when reverse command is applied .. and its puzzling to say the least so wondering if anyone has any ideas please ... the transmitter is a Hobby King HK-T4A  V2 and the ESC a Hobby wing quick run 1060 ... a pic of the motor etc layout is attached ..

[Allen A]

Here's the on/off switch ... now you see it ... now you dont ...

[Backerther]

Hi Allen A,
To begin with, please allow me to post many pics in your thread of the PT boat.
I am putting the pics here taken in my crucial experience to cope with water leakage generated in a PT boat-like speed run
on the lake, expecting to be of some reference for your future test run. The Lindberg kit of this boat might have been intended
for use on the pond like water at slow speed, judging from the design and construction put into market so many years ago.
You are ready to start the test run on the water (pond?)which will be comparatively easy to go.
But if you should intend to get her to run at a PT boat like speed on the water (large pond or lake) in the future, intensive
countermeasures against water leakage may be required from my own experience. Unless you do that, your boat will disappear
on the water at worst case...   My PT-109 is 1/32 Lindberg make and yours look the same...
1/2/3/;Around the detachable deck must be processed against the leakage. A Pt boat is so low a freeboard.!!
          I later applied very thin coat of so-called bath-cork around the deck by which leakage could be almost shut it out.
         I also used some magnets to get the deck to fit better.
4/5/6;Switch was processed as seen in the pics. using rubber inside the deck and some grease was filled in the tiny space.
7; My PT-109 has been sailing like the real one on our local lake with no problem currently. a bit too fast....for a scale model


Needless to say, both stern-tubes were also filled with grease completely.
Take care of motor cooling as well if you should get her to run fast.!!
The ESC is to be set a bit higher level lest it should be wet for possible leakage.

Hope your successful shake-down run. !!

[Allen A]

I don't mind at all and thanks for the tips ... I have two of these at present, one of them being the original one I started this topic about and that is more or less as I want it and sails well although in as much as the only open water close to me is a canal, I haven't taken to full speed as yet but it leaves a decent wake I think?


The other is the one I'm having problems with, as although 'finished' to a point and sails too, it is not smooth and as I say, the problem is that although on a stand thee  motors respond to a fwd and reverse command from the transmitter,  when on the water it goes forward in reverse too ... I know weird ....  Im wondering if I set the ESC right ??


Pics attached are of the original underway and the two of them together, the original one being closest to the bank ..


Nice shot of yours at speed ... hoping to get there with mine ...

[Circlip]

Err, don't forget the 4mph speed limit on the canal Allen 


 Regards   Ian.

[Allen A]

Hi Ian ..    .. good point ... not much chance of that though as conditions weren't ideal, a bit windy and a bit of a swell, plus I cant seem to get the turn of speed I feel should be there ..?


Im beginning to realise there is more to RC than meets the eye, not that simple a thing to master, oh I can build them OK, even 'dress them up' a little for effect but on the power side of things I am a complete novice and am left to wonder if I've got things set up right.. The transmitter is a FlySky FS-14X, the receiver a FlySky FS-A6 with a Viper Marine 15 ESC, all powered by a 2900mah, 11.1 volt Lipo battery. The motor is a large 12volt one, sorry cant read the make due to how its mounted, I'm also left wondering if these boats need some ballast as it can wallow a little in a turn .. any help advice will be gratefully received 


A picture from another test sail yesterday, sorry about the quality but my D800 didn't seem to like the 28-80 lens I was using .. ???

[Backerther]

Hi Allen A,
Sorry again to post many pics on here.
I'd like to show you here my set-up of 1/32 Lindberg PT-109 just for reference focusing on your embarrassment in the test run of the boat.
1/2; As for ballast, no special ballast required and a heavy battery will do instead if installed as low as possible as seen in the pics.
       In my boat,2S 5000mAh lipo has been doing so nice a job as seen in the video below. The motors are Mabuchi 540s.
3; Maximum rudder throw is as this level which has been rarely used in normal sailing (at speed) for safety.
   Wallowing may posssibly take place at low speed with low draft...?? Even my boat wallows at starting stage, see my video.
   You possibly had better install a heavier battery like mine instead of so-called ballast....This boat is generally light and a heavier battery will work effectively as a good ballast.  3S/5000mAh is generally 100g heavier than 2S/5000mAh which difference will be helpful for better ballast.
4; The battery is doing a good ballast set at lower position. 
5/6; Recently I am using 4 pieces of screws to get an ultimate water-proof effect. Thanks to this, even a teardrop of water is not found inside the hull.


With the content of video below, I judged this boat as complete as a scale serviceable model PT boat on the lake
https://www.youtube.com/watch?v=R7QKh8ptwj0&t=21s

[Allen A]

Hi again, and thanks again, that looks a neat layout you have inside the boat .. should perhaps try tidying mine up a bit ?

A thought has occurred to me here, in fitting lights to my model and powering them from the receiver channels, would that effect the power output at all .. ??  (pics attached to show the effect) and I know that in WWII the lights wouldn't have been used much but they would have been able to turn them on and off as necessary I'm sure and it makes the model a little more realistically complete for me.  other pics attached are to show the overall finish of this one, the on/off switch being hidden under the small box between the Oerlikon lockers .

Watched the video ... yes that's the way I feel mine should be running .. and Im glad to say mine is dry inside too !!

[Backerther]

Thanks for many interesting pics of your PT boat.!
Hiding a switch is ideal and you did a very nice work on this point as well as lighting gimmic. The lighting in the dark is generating special atmosphere and may be enjoyable if seen actually in the room or at the water front?
Basically, I don't intend to set a lighting gimmic on my boat models as my principal purpose to build them is just to sail them on the water in the daytime only, not in the night nor evening when is nearly dangerous and impossible to operate on the water.
If I should build a static model ship/boat, a lighting system must be set preferentially.
My primary interest in the Rc model ship/boat is just how I should build a Secure , Safe and Scale like run/movement on the water in the daytime. If possible, Silent characteristic is additionally important when sailing on this local lake.
 I am required to seek for this "4S"models to sail as far as on this lake....  

[dodgy geezer]

..................................
Im beginning to realise there is more to RC than meets the eye, not that simple a thing to master, oh I can build them OK, even 'dress them up' a little for effect but on the power side of things I am a complete novice and am left to wonder if I've got things set up right.. The transmitter is a FlySky FS-14X, the receiver a FlySky FS-A6 with a Viper Marine 15 ESC, all powered by a 2900mah, 11.1 volt Lipo battery. The motor is a large 12volt one, sorry cant read the make due to how its mounted, I'm also left wondering if these boats need some ballast as it can wallow a little in a turn .. any help advice will be gratefully received 
...............................

Your problem is a lack of speed?  Then the Tx and the ESC are probably not an issue. It will most likely be your power train.

1 - Is the battery putting out a good amount of power? If it's a LiPo it should be, Unless something is wrong with it.
2 - Cables. If you have a very thin motor cable it can't carry the power needed and will just get hot.  I suspect yours is OK...?
3 - Your 12v motor. What does it rev at?  Not all '12v motors' are the same - they can be designed for all sorts of jobs. A 12v motor driving a turntable is not going to put out the power to drive a 30" hull (though it will be nice and quiet and very stable...)
4 - The coupling and prop-shaft. Do they turn freely?  A prop-shaft full of grease can stop a motor with its drag. 5 - And sometimes the most important - the prop. Changing a prop can make a huge difference to a boat's performance. Lots of people have several different ones to try them out for best results...

P.S.  While I don't think it's your ESC/TX, you can easily test this by hooking the motor up directly to the battery and confirming that full power from the ESC and full power connected directly sound about the same...

[Allen A]

The lighting in the dark is generating special atmosphere and may be enjoyable if seen actually in the room or at the water front?
Basically, I don't intend to set a lighting gimmic on my boat models as my principal purpose to build them is just to sail them on the water in the daytime only, not in the night nor evening when is nearly dangerous and impossible to operate on the water.

Hi, if I can start this reply by saying I am also a living history re-enactor, (complete with all that that entails), you may understand where I'm coming from with the lights for one thing, I don't see them as a 'gimmick', the reality being that these boats had them and for me to include them is part of trying to realistically recreate these historic boats in miniature as we do. Ultimately (if I can that is) I would like to be able to switch the lights on and off from the transmitter, and yes of course from a safety aspect I wouldn't sail it at night, but .. think of the effect at twilight on a summer evening or even at early dusk in winter .. ??


Research is a great thing and I have bought some books on PT Boats and researched them a fair bit since having the original and now the second one too, a fact being that in reality the only time they probably all looked alike was when they left the shipyards where they were built, the truth being they were heavily modified, not to say 'personalised' by the Capt. and crew to suit their location and effectiveness in their duties and in that respect no two boats were ever the same I think, and that's something that to a degree gives us carte blanche perhaps in modelling this particular type of boat, but within reason and historic bounds of course, and this is also why I stated 'not 109' in my title as I wanted to make a somewhat generic PT boat, and that's why also I haven't numbered it, however in as much as some were named, that's a thought I still have in mind ??

[Allen A]

Your problem is a lack of speed?  Then the Tx and the ESC are probably not an issue. It will most likely be your power train.

1 - Is the battery putting out a good amount of power? If it's a LiPo it should be, Unless something is wrong with it.
2 - Cables. If you have a very thin motor cable it can't carry the power needed and will just get hot.  I suspect yours is OK...?
3 - Your 12v motor. What does it rev at?  Not all '12v motors' are the same - they can be designed for all sorts of jobs. A 12v motor driving a turntable is not going to put out the power to drive a 30" hull (though it will be nice and quiet and very stable...)
4 - The coupling and prop-shaft. Do they turn freely?  A prop-shaft full of grease can stop a motor with its drag. 5 - And sometimes the most important - the prop. Changing a prop can make a huge difference to a boat's performance. Lots of people have several different ones to try them out for best results...

P.S.  While I don't think it's your ESC/TX, you can easily test this by hooking the motor up directly to the battery and confirming that full power from the ESC and full power connected directly sound about the same...

Hi, thanks for the reply and advice and to answer your points  one by one
1) I think the batteries are fine, bought as new and are both Lipo 2900 mah 11.1 volt 3S types, I also have a Lipo 2200mah 7.4v 2s as a spare and don't have a problem with them on the face of it all.
2) The only cables I have 'played with' are the ones I fitted to power the lighting, all others are as supplied with ESC etc and have never felt warm.
3) Now the motor, this is a replacement as my very first run with the boat was in a fish pond with lots of reeds, yes you guessed it jammed prop, burnt out motor. I have no idea what the motor is as there are no markings on it at all and I don't have the box, but I am beginning to suspect this may be part if not all of the problem ... and wondering if you can suggest what power (amp wise) motor would be suitable for the ESC/TX and batteries combo in order to get a semblance of it running as per that video clip for example ?
4) Coupling and prop shaft seem fine, nicely inline but a fraction low in as much as the motor is touching the underside of the upper deck area, but it runs smooth none the less the joint handling the very slight angle well.
5) Not thought about the prop and will take that under advisement ..


However, now a cautionary tale and a slight catastrophe ..  The lighting on both boats was powered from different channel connections on the receiver and it trying to work them out I did notice they could affect the motor and/or rudder servo power, this is why I wondered if using the channel outlets for the lights was a good idea .. so today I decided to rewire the lights and plug them into the Batt terminal on the receiver and it worked on the first one (ie the second boat) I did .. thing being when I came to my original, despite extreme care while checking the wiring before soldering, something shorted and I burnt out the ESC .. don't ask ..  boy can those things burn ..    ... luckily there is no other damage, some smoke stains and just burnt out wiring on the ESC .. thing being perhaps a good thing in a way as in repairing I may look at getting another motor as well as the ESC in order to hopefully improve power and performance the way I would like to.

[JimG]

However, now a cautionary tale and a slight catastrophe ..  The lighting on both boats was powered from different channel connections on the receiver and it trying to work them out I did notice they could affect the motor and/or rudder servo power, this is why I wondered if using the channel outlets for the lights was a good idea .. so today I decided to rewire the lights and plug them into the Batt terminal on the receiver and it worked on the first one (ie the second boat)

It doesn't matter which channel you plug them into on the receiver. The positive and negative connections are linked together on the circuit board so all the channels get the same power. The only difference is the battery connection doesn't have a signal output so won't run a servo. In many receivers there is no seperate battery connection and one of the output channels is used for power input, normally the last in the sequence, if needed for a servo a Y lead is used to allow for battery connection.  (many 2.4 GHz must have a seperate battery connection as this is used for a binding plug to allow setting it up with the transmitter, one of the other channels is used for the battery while doing this.)
Jim

[dodgy geezer]

.................... I have no idea what the motor is as there are no markings on it at all and I don't have the box, but I am beginning to suspect this may be part if not all of the problem ... and wondering if you can suggest what power (amp wise) motor would be suitable for the ESC/TX and batteries combo in order to get a semblance of it running as per that video clip for example ? .................................

I'm afraid that I'm more used to brushless motors - but I'm sure that you will get no end of advice here in a while!  Graupner Speed motors have a very strong following...
It may be hard to model a wide variety of PT Boat variations if you are limited to plastic kits. Perhaps you would like to make up some EeZeBilts? You will find a couple of my PT boats here:
http://eezebilt.tk/PTB10.html
(I don't seem to be able to post images :(  And yes, I know that PT boats didn't have planked decks - but I just liked the effect...)


 

[Allen A]

It doesn't matter which channel you plug them into on the receiver. The positive and negative connections are linked together on the circuit board so all the channels get the same power. The only difference is the battery connection doesn't have a signal output so won't run a servo.
Jim

Hey Jim, thanks for that, had no idea of the ins and outs of them, just more or less what they did.
I did initially, when I first got it all, plug the ESC into the batt link on the receiver, seemed to be a logical thing to do, and then wondered why I had no throttle power, took a while to figure out but managed to get there, just out of interest I had the throttle command into Ch 3 and the servo into Ch 1 and they seemed to work OK at that, somewhat academic now of course while needing to get a new ESC and perhaps a motor too,  and in that respect the original boat is in dry dock for now.


Its back to the No 2 boat, the problem there being that while on face of it it is finished and 'works' when its on the stand ie; the motors spin ok in fwd and reverse from the TX control command, when in the water, although it moves fwd as it should, it also moved forward when the reverse command is activated ... my mind is working sideways on it and Im wondering if the props could be too close to the rudders, or bearing in mind a previous comment of yours, if I need bigger props, so for now getting that sorted is my focus point.
It is also a little slow I feel, the problem being I am probably going to keep the original No 1 boat and sell this one on and whereas I want it to be working right, don't really want to spend excessively on it.

[Allen A]

It may be hard to model a wide variety of PT Boat variations if you are limited to plastic kits. Perhaps you would like to make up some EeZeBilts? You will find a couple of my PT boats here:
http://eezebilt.tk/PTB10.html

Hi ... I take your point re plastic kits but there are quite a few extras in 1/32 scale out there made in a variety of materials that all lend themselves well I think to accessorising these models, even some parts to replace the plastic parts that come with the kit.
I have cheated a little too in as much as on both boats the torpedoes peeking out of the tubes are Italeri 1/35 scale ones that with a bit of inside modification to the 1/32 scale tubes fit and look well I think, some of the crew too are 1/35 scale. the thing being that not everyone is/was the same height so leeway there for a bit of modelling licence perhaps ?
Whereas I am happy with the Lindberg, I must confess for a liking for the Italeri ones given the extra degree of detail they have and would consider getting one I think if I had more experience in setting up RC, the Lindbergs seemingly lending themselves easier to fit motors and RC gear etc in ??
Pics attached of some of the 1/32 scale extras I bought for the boat ..metal some of them, some resin but all fairly well made too .. also pics of the two torpedo's in the tubes I mentioned, by the way, the man on the wood box is the on/off switch on the No 2 boat 


I like the look of the eezibilt I think, and your boats look good too, well done ..

[dodgy geezer]

Those are the old Mk 8 torpedoes in tubes  If you have (or can get access to) a 3-D printer, I have drawn up some Mk 13s, complete with launching racks, which are what I use on the EeZeBilts now.  I could put the .STL files up on the website for you to download if you want...
I would put some pictures up if I knew how....


 

[Allen A]

Yes, the Mk 13 aircraft torpedo's started to be used in 1943 .. according to navy legend two PT boat officers came up with the idea of rolling torpedo's off the way they did depth charges only the Mk 8's weren't suitable due to gyro pre-settings etc .. whereas the Mk13's gyro could be and were set and started by hand before they were rolled off.. 

I don't have access to 3D printing thanks, so will leave these as early type boats but if I do another may have a go at it being a later model .. apparently towards the end of the war a lot of PT boats didn't have torpedo's at all, becoming more or less simply gun boats.

[Allen A]

 Perhaps you would like to make up some EeZeBilts? You will find a couple of my PT boats here:
http://eezebilt.tk/PTB10.html

Hi again ... referring to your pictures in that link, and your comment on one of them about a grill on the engine room intake, they did in fact have something on there as you suggest .. found an original pic from the time that shows this fairly clearly, its attached for your reference .. 

[dodgy geezer]

There's certainly something there - what it is, I don't know....  Could it be an opened door?
These drawings are not much help...http://www.pt103.com/Italeri_PT109_Kit.html#enginehatch

[MikeMcP]

looks to me like an opened hatch, hinged along the bottom?
strictly non-mariner me!