I see a gear driven setup in the picture.Will you use the same set up for the new build.Would you be able to show the geared set up.
Rick

Pedal on Doug the batteries are getting low.
Rick

"and then we'll have to come back to sail and oar."
Good ole Nerys😉 always sticking 'er oar in!😮
😁😀
OK OK I'm off to me Pelaton bike to charge up the house batteries⚡⚡⚡
😎

Hi Colin,
If I were you I might go for the 5 pole 385s instead of 380s.
They should give you much smoother control at low manoeuvring speeds.
You then may not need the gearbox(es)😉
Even with the gearboxes I think the 385s would be better.
Cheers, Doug 😎
BTW The gold ESC in your pic reminds me of the Hitec SP-6 ESC I had in my Sea Scout, then briefly in HMS Hotspur ca 30 - 35 years ago! Still got it, an' it still works😊

Should be room for 2 off 380's with small gearbox, the picture is of my old paddler setup.
Hopefully this next one will be tidier.
Cheers Colin.

The steam engine I saw Colin looked quite narrow and had a shaft coming out of it on each side. I wouldn't have thought it was any wider than twin electric motors, but there, I'm no authority on these new fangled steam and infernal comboostion things.
They won't last you know, we'll run out of coal and stuff and then we'll have to come back to sail and oar.

Cheers, Nerys

Good luck with the build Colin.Will you have room to install two motors.If so will they be belt drive .
Rick

Contemplation is the precursor to procrastination Nerys!
'Strike while the iron's hot!'
(No one likes a hot iron round the lug'oles! 🤕😭)
😁😎

Paddlers intrigue me Colin, though I have never considered building one. I became acquainted with them at a very early age being taken on day trips from Barry to Weston or Minehead. The nearest I came to owning a model was when I contemplated buying one on the 'bring and buy' stall at one of the shows.

Cheers, Nerys

Nerys, steam power is out of the question, as its quite a slim Hull.
So it will be twin motors with individual driving paddle wheels. Although the plan shows single drive.
Cheers Colin.

Your Edwardian paddler sounds interesting Colin. Is she any particular ship, or just a generic paddler? If she isn't already steam powered, will you convert her to steam? I see there is a steam engine designed for paddlers on the market.

Cheers, Nerys

Doug ,Colin My error, it is the way you say for the wheels turning .
Rick

Well Doug, mine was a finished model given to me by a fellow showman at one of the shows.
But I have just acquired an unbuilt kit of an edwardian paddler(Shah don't tell the wife), to build while stranded away from a sailing venue.
Looking forward to working on twin motor drive systems.
Cheers Colin.

I agree Colin👍
The outside wheel surely goes ahead, the inside wheel slows, stops or goes astern if the Cap'n wants to show off and make the passengers dizzy!🤔😁
"my paddler always turns better on the wheels rather than the rudder."
I believe the real paddlers were the same, especially at very slow speeds.
Would very much like to see yours in motion😀
Never considered building a paddler, too complex for my non mechanical mind🤔
Cheers, Doug 😎

Shouldn't that be outside wheel keeps turning, my paddler always turns better on the wheels rather than the rudder.
Cheers Colin.

I to can vouch for the P94 action component.I use it in my paddle steamer.Very helpful when turning as the unit is hooked into the rudder servo.I have independent paddle wheels that when the rudder is turned port or bow the wheel opposite the turn slows or stops inside wheel keeps moving to help the turn.
Rick

I can vouch for the P94 absolutely brilliant and user friendly too.
Don't need to be a sparky to sort it out😀😀

Thank you everyone for the encouragement and advice you have given me on this subject. Thank you Doug for the wealth of information you gave me, I had been following this thread, but it was good to have the more relevant bits pointed out to me. I would go to Cornwall model boats for everything anyway, how I wish we could have a run out there to go and get the stuff, but we are banned from going outside our area and I don't think Cornwall have an actual shop. Deans don't mention propellors, surprising really because LSTs carried two spares on deck. Anyway, I'm psyching myself up to the build and I know I will get all the help and encouragement I can possibly need on this forum.

All the best to everyone. Nerys

"God knows what we would do without you. "
Whoever he may be😉
No rocket science Colin, if I hadn't replied someone else wooda!
I've used a pair of 385s on two 6V SLAs in my 107cm, but much sleeker and slimmer U Boat, and it makes RTR 'speed' boats look plain silly😁😊
Muchas chuckling from me, muchas grumbling and long faces from the boy racers😁😁
Cheers, Doug 😎

Very impressive Doug, I'm sure Nerys will get all the help she needs, God knows what we would do without you.
Cheers Colin.

Thank you for the VoC Colin😀

Nerys,
Most of your questions are already answered below, esp. re two motors on one ESC😉
Yes, but ONLY with brushed motors. You won't need brushless for a slow, hefty displacement hull. I don't suppose you want to get into LiPo batteries either.

Actually earlier LSTs had a top speed of around 18knots.
But you're right, the Mk2s, such as 388 or your Dad's 368, top speed was around 12/13 knt and cruising speed 10knt.
Model-wise-
Your model is (will be) a tad over 1m.
For comparison
My 1.35m, but much slimmer, destroyer goes like the proverbial off the shovel with two 540 type brushed motors on 12V (2 x 6V in series).
I reckon for your LST 2 x RS385 type will be more than adequate, with some reserve.
I say 385 and not 380 as the 385 has 5 poles and thus starts and runs much smoother than the 3 pole 380s. They'll draw about 1A or so on load and stall current is about 4 to 5A.
They have short circuit (jammed screw) protection anyway👍
Suitable 385s you can get here at Cornwall Model Boats. Nice trip out to pick 'em up, if you're allowed🤔
https://www.cornwallmodelboats.co.uk/acatalog/mfa-re385.html#SID=2304
ESCs
If one per motor then perhaps Mtroniks Viper Marine 10.
https://www.cornwallmodelboats.co.uk/acatalog/mtroniks-viper10.html#SID=2177
If one ESC for two motors then Mtroniks Viper Marine 20. Cheaper than two Marine 10s as well😉
https://www.cornwallmodelboats.co.uk/acatalog/VIP20PNP.html#SID=2177
Battery;
The motors are most efficient at close to 12V, and your model will need a fair bit of ballast, a pair of 6V 10Amp hour SLAs in series (as in my destroyer) will do nicely. And run your ship all afternoon, ca 5 hours at least. e.g.
https://www.cornwallmodelboats.co.uk/acatalog/vrla6_10.html#SID=426
If 4kg (2 x 2kg) is too heavy then-
https://www.cornwallmodelboats.co.uk/acatalog/info_P5510035.html#SID=426
These are 4Ah and weigh less than 1kg each. Should be good for at least 2 -3 hours running.
If you can fit this 12V 7Ah SLA in it should give you a run time of 3.5 to 4 hours or so and weighs only 🙄 2.2kg.
Contra rotation?
Yes. I've read in the LST development history that the engines were designed so that the shafts could be coupled at either end. So to reverse one shaft they simply installed that engine bassackwards😁 For best manoeuvrability I'd recommend inward turning shafts, as the ship only had one rudder. I.e. to move ahead and seen from behind; port prop turns clockwise and the stbd prop anticlockwise.
Deans don't mention them bit I assume the props are included in the kit as the shafts and toobs are.
Hope this helps. Now stop your 'argy bargy' and clear the decks for Dad's LST!😁
Cheers, Doug 😎

Good evening Nerys, I'm sure the answer will be forthcoming from Doug,
Cheers Colin.

When I actually make a start on my LST, not long, one of the first jobs I want to do is to get the two motors installed. The prop shafts come as part of the kit. Now being a strictly sticks and string girl, I'm out of my depth, so, bearing in mind that the original LSTs had a top speed of 10 knots, I don't want to have a set up that has her planing across the lake. So, please what motors would you advise me buying, what props, should they be contra rotating? can I run two motors off one ESC? and anything else I haven't thought of.

Cheers, Nerys

Excellent Colin, Those ESCs are ideal👍
They cover the stall current of the motors as well, which is very good.
So 15 or 20A fuses (or circuit breakers😉) in the motor leads and a 30A in the + battery to ESC lead.
Which TX / RX set will you be using?
Cheers, Doug 😎

Cheers Doug, I have 2 viper marine 20 amp sets available, and I'll check out my tx instructions.
Cheers Colin.

OK. Which ESCs do you have available?
Depending on your radio set you MAY be able to use a mixer function in the TX.
I.e. one that's actually intended to mix control surfaces on a fixed wing aircraft.
Have a look in the manual of your TX to see if it has a 'W-Tail' mixer function.
You should be able to mix throttle and rudder with that, as the Action board does!😀
Bon chance mon ami🤞
Cheers, Doug 😎

Thanks Doug,
I've just printed your info, very helpful. A great system but currently above my means. So added to xmas or sooner wish list.
As I already have suitable esc's I might delve into having a go at building a mixer board myself,, gotta learn about electricary sooner or later.
Cheers Colin.

"it will keep cutting out until you remove the weeds 😊 "
Yes Catman, esp if you give full throttle forward.
But it may give you a chance to blip the throttle in reverse to try to unwind the weed.
Either way, main thing is your boat doesn't go pyrotechnic!🔥😭
Cheers, Doug 😎

"fuses and breakers are intended to save one's wiring,"
Absolutely right Jonathan👍 that's where the fire hazard is!
"the fuse should be designed to save the wiring that feeds the motor and ESC"
Precisely! That's why I looked at the stall current of the motors.
You may have a 60A rated ESC but it's the motor that sucks the current.
In the tests that I have done over the years I find that there is usually a 10 to20% safety margin in the rated stall currents.

Yes I have a few resettable blade type circuit breakers myself.
Used mostly in single screw boats. They are significantly more expensive than the big box of assorted blade fuses I bought some time ago.
In twin screw boats, such as Colin's here, it's maybe not so critical.
I've only ever managed to jam one screw on my destroyer and limped home on the other.
With a lot of rudder to compensate the lop sided thrust!
Thanks for your informed input👍
Cheers, Doug 😎

the problem is it will keep cutting out until you remove the weeds 😊

Doug,
if I may, I would suggest using resetting fuse, or circuit breakers over here. There is not too much worse than blowing a fuse due to weed or sticks in one's prop and waiting for the wind to blow your boat in, if you are so lucky. With an automatic reset breaker, the reset occurs as soon as the breaker cools don and it give s a chance to get your boat back.
Easily obtained from auto part stores they are very inexpensive, tiny in size and pretty reliable.
last point, fuses and breakers are intended to save one's wiring, not so much so an ESC. That should be done by matching the motor requirements to the ESC. That said, if one's ESC has a high rating, say 35 amps, and the motor only draws 5 amps, the fuse should be designed to save the wiring that feeds the motor and ESC, which should be thus properly sized o that requirement. If we use the ESC as the designator for the fuse size, the wiring will probably melt first.Not an ideal situation.
Jonathan

8 amp would be my call fuses are cheap esc not as much I still have a large stock of fuses from 22years in STC /Nortel LOL👍

It might look like that Catman😉
But 10A is the continuous rating of the ESC. It will stand much more for short periods.
Perhaps I should have mentioned that the fuses should be Quick Blow types!
Post was getting long enough already.
Perhaps 15A fuses would be a tad safer. Much lower and they might get popped by short term current transients.; fast start up, back emf from abrupt stops / reversals!?
For very high current motors and ESCs it's slightly different story, greater fire risk, and I would recommend fuses much closer to the max continuous rating of the ESC.
Cheer, Doug 😎

i might be reading this wrong but would that mean that the 10 amp esc blows to save the 20 amp fuse ?

Hi Colin,
Here the specs of your motors from the Cornwall Model Boats site-
https://www.cornwallmodelboats.co.uk/acatalog/cem900.html#SID=2300
"High Torque 900 motor from Caldercraft Electric Motors (CEM).
Nominal Voltage: 12V
Operating Range: 6-18V
RPM at Nominal Voltage: 3000
No Load Current: 0.4A
Current at Nominal Voltage: 5.0A
Stall Current: 20.3A"
Thus, running on 12V as you seem to be planning, any brushed 10A ESC will do for one motor and give a decent safety margin. E.g. MTroniks Viper Marine 10 or similar.
I have a few Viper 10s and find them very reliable with 540s also drawing around 5A.
Also fit max 20A fuses in one lead to each motor, to prevent a total STOP if one screw gets jammed. You can run both from one ESC.
The ESC must then have 20A capability to have the same safety margin.
But if you run both from one ESC they can't assist the steering by themselves.

I assume that 'use the motors to assist the series' should read '.. to assist the steering'?😉
To do this you have two choices-
1 To fit one ESC per motor and use two channels to control them separately.
So called Tank Steering using two sticks on the TX.
Not my choice, as you waste a TX channel, need two hands on the TX and it ain't easy!
My recommendation would be-
2 Use something like the Action Electronics / Component Shop P94 dual ESC with integrated rudder mixer. As I'm doing with my Southampton tug. You can then use just one stick (and one thumb😉) to control both motors and rudder with motor assisted steering.
Pirouette on the spot if you wish 😁🌪️🌪️🤕
Other hand free to operate other functions, lift your tea cup, scratch your nose etc etc😉

You CAN get separate mixer boards to connect to two separate ESCs but it ain't much cheaper and in my professional opinion such a set up just adds more wires and 'potential points of failure'. The P94 is the KISS solution😉 the 10A (Lite) version should do.
https://www.componentshop.co.uk/p94l-dual-esc-and-mixer-2-x-10-amp.html
Pdf spec and operating description attached.
Cheers, Doug 😎
PS "And no I wasn't taking the Michael earlier. " Didn't think you were. Just playing the irascible old Admiral and pulling your anchor chain😁