Model Boat Mayhem
Technical, Techniques, Hints, and Tips => The "Black Arts!" ( Electrics & Electronics ) => Topic started by: sparkey on August 09, 2014, 09:39:44 am
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;) Over many years of enjoying our great hobby I have noticed that the state of wiring in a lot of model boats is to say the least poor, some really wonderful boats let done by the wiring and broken down in the middle of the lake,I have spent many Sunday mornings soldering iron in hand helping other boaters with their wiring,not that I mind I quite enjoy it but would it not be better to sort it out before you get to the lake,if it looks neat and tidy it usually won't let you down so come on guys lets up our game,just a old man having a moan,hope you all have a great sailing weekend with not too much rain,Ray. ;)
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Ray
You're a man after my own heart. How many times I've seen a beautifully-made model with wiring like a rat's entrails; the wrong size battery for the motor used, wire which is too thin (or thick) for the job, choc-block connectors for high-current circuits, wires joined by twisting them together, PVC insulation tape wrapped around such joints - the list goes on. Whenever any observation is made about it the owner trots out some remark like "O, I don't understand electronics" as if that's a sort of badge of honour.
Operating electrically-powered model boats and not having a clue (or a care) about the basics of DC electricity is not cool - it's just lazy, or worse.
There's a link here to the Model Boats website where you'll find an article which covers just about everything you need to know - and there's no 'electronics' involved http://www.modelboats.co.uk/news/article/but-i-don-t-understand-electronics/18054 (http://www.modelboats.co.uk/news/article/but-i-don-t-understand-electronics/18054)
With suppliers like Component Shop who can sell you practically everything you need in the way of cables, connectors, batteries, chargers, switches and a whole range of model boat electronics then there really is no excuse for those horrible installations Ray mentions.
In my experience as a manufacturer of model electronics most of the problems which arise are the result of poor wiring or flat batteries. Less than half the units sent back for repair actually have anything wrong with them, and of those which do most of the faults are caused by incorrect connection or other abuse by the owner.
Like Ray says, if it looks right then it generally is, and it's much easier to trace a fault if you're not being attacked from all directions by loose wires!
My regime for wiring a boat is straightforward:
- Plan the job and get the right materials together before you start. Don't make do with something which isn't right for the job just because you have it to hand.
- Charge up all batteries before starting any installation.
- Start the job with the main battery and cable it up to the main switch - then test it.
- Fit any fuse and retest.
- Continue adding one unit at a time and testing it, then disconnect the battery and add the next unit. Don't wire everything up all at once and leave testing to the end. If you do the job in stages then if anything does go wrong you'll know that it was the the last step which caused it.
If it was rocket-science then I'd have taken up basket-weaving long ago!
Dave M
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I always try to go for a smart wiring install, but it always ends up looking like an explosion in a spagetti factory
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I was always taught by the late Bernie Wood to keep all wiring short as possible, away from moving parts if possible, clipped together if possible, and generally nice, neat and tidy.
I managed to nearly lose a sub when a loose wire got itself trapped around the air pump and was ripped off, leaving me submerged with no power to the ballast pump, and no way of surfacing. Luckily for me, Bernie always carried in his tool box a length of thin string with either a floating ball or a lead weight attached, depending on what was needed. Two casts later and the boat was unceremoniously dragged to the surface, and the wire repaired.
Ever since then, I always strive to keep The Great Man's advice in my mind when attempting any wiring in a sub.
Rich
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This is one of the things that I've never understood - most of the people on here are showing photos of boats that are worth hundreds of pounds, yet if you look inside some of them, the equipment is bodged together with bits of old choc-block and ten tons of spaghetti.
I often see a rough old bit of ply with holes hacked in it to mount servos and motors. I see batteries loose to move around, wiring resting on motor couplings, motors with no suppression caps, loose receivers laying in the bilges and wiring for lights just thrown in.
With all of the ty-wraps, self-adhesive wiring clips, heat-shrink tubing, fibreglass & epoxies and composite boards that are available for pennies from ebay, why do people skimp of these important parts that give reliability?
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For those who are forever pulling off spade terminals at the lakeside:
All too often these end up loose and an endless source of problems, especially when I see them getting re-squished with pliers for the umpteenth time.
With an adequate power/charging switch and freshly recharged batteries of enough capacity they need never need disturbing.
I would recommend the spade terminals from Component Shop that have a sprung detent latch.
http://www.componentshop.co.uk/1-4-spade-terminals.html (http://www.componentshop.co.uk/1-4-spade-terminals.html)
Always crimp and solder joints, with colour coded heatshrink sleeves over all exposed connections.
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This is the radio box of the little Jelly Bean 4 submersible..got a way to go as yet, I'm waiting on the esc to arrive, then I can finish off tidying and clipping down the stray wires, but it gives you an idea of how I do my wiring.
Rich
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Here is one from Shittyelectrical on Facebook - it s a thing of beauty for us electricians
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:-)) Oh such a wonderful sight,have done one or two great installations in M.I.C.C ,conduit, trunking and cable tray,the best one was in the Royal Festival Hall back in the late 60s when it was rewired but has been rewired again since,the hall was built just after the war for the Festival of Britain and a lot of the switchgear,contacters ect. must have pre-war when built, when we removed them they where on there last legs and always breaking down,the down side was we didn't know about asbestos,mercury and all the other nasties that was in the old control gear,luck is I am still around I wonder how many of the other sparky's are,Ray. :-)) :-)) :-))
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Seriously?
This guy has obviously never heard of trunking? I'd be REALLY miffed if a contractor did that in my house!
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;) I think you will find that is an industrial installation or maybe on a ship what ever it shows a great deal of craftmanship and skill,however I have seen a great deal of cowboy installation mainly in domestic houses,usually if the sparky has taken this much trouble on the outside you know the inside will be the same first class,Ray. ok2
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;) I think you will find that is an industrial installation or maybe on a ship what ever it shows a great deal of craftmanship and skill,however I have seen a great deal of cowboy installation mainly in domestic houses,usually if the sparky has taken this much trouble on the outside you know the inside will be the same first class,Ray. ok2
It's domestic - the floorplan is on the lower left of the picture.
I'd sack a sparky if he did that in an industrial installation!
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It is the kind of work which we make you do to the school or to the army.
It's useless but that pleases the instructor
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It is the kind of work which we make you do to the school or to the army.
It's useless but that pleases the instructor
Yeah - they used to make the YTS trainees do that type of thing years ago to practice using clips and grommets but you'd never do it like that for real!
Even the Americans don't do it like that normally!
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I think it's for a hotel so it gets the commercial touch!
I wish some of the sparkys in the dockyard would do stuff like that. I get to check new cable runs as part of my job and a lot of the runs are a right snakes nest
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But I must admit I would be happier if it was in conduit
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Looking at the floorplan, I'm pretty sure that it's a domestic installation in a 3-bed single-storey US house - they colour (color) code the wires depending on use.
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I started this thread about model boat wiring and look guy's we have really drifted off course, so can we see some wonderful posts about wiring on your boats,and some photos please,Ray.
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Lol, my springer tug started with nice, tidy runs but upgraded to two batts plus tried a few of my strange ideas out ( kind of used the springer as a testbed for other projects) and it got real tight on space so to my shame ended up a bit of a mess. Lessen learnt, don't rush it, do it properly from the start. I did have great intentions once I worked out the working crane thing of making a proper loom but managed to kill it before that happened
Currently building a twin prop modern tug - photos will follow but this one I am taking my time with and doing things properly as I was taught.
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It's domestic - the floorplan is on the lower left of the picture.
I'd sack a sparky if he did that in an industrial installation!
Why, because of the labour involved.
Look past that point and think how simple it will be to fault find and trace any defects or alter the installation.
Recall it being said early on in this thread the aim of wiring was to simplify fault finding and any repairs.
Square or rectangular ducting with removable covers is acceptable :-)) :-)) but round conduit with saddle clips is ugly, I reject them, round conduits, every time. O0 O0 O0
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I agree with Sparkey's original post concerning shoddy wiring in otherwise well made boats. I went to the trouble of building a pusher tug for use as a rescue vessel at our club lake. On the first day I took it to the lake I made 4 rescues, all of which were due to faulty electrics, and have made dozens of rescues since that day in December 2007. Most of the electrical faults were traced back to poor connections, and a number were due to flat batteries. Nearly all the problems were preventable.
Peter.
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This is the radio box of the little Jelly Bean 4 submersible..got a way to go as yet, I'm waiting on the esc to arrive, then I can finish off tidying and clipping down the stray wires, but it gives you an idea of how I do my wiring.
Rich
Uggett
That doesn't look like a 2G4 receiver to me, yet there's no suppressor caps on that noisy little motor. Take three black stars and go stand in the corner.
DM
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That doesn't look like a 2G4 receiver to me...
He did say "submersible". I'd take a star back and let him sit in the corner. %%
Andy
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They're my black stars and I say who gets them - and how many. :P Just because it's called a submersible doesn't mean it's going to submerge. After all, model lifeboats don't save lives and model trawlers seldom catch fish etc etc ;D
Rich is old enough and ugly enough to know better. I suppose he could try pleading poverty but 0.1uF ceramic caps are 5p each if you know where to buy them. In all seriousness suppressor capacitors should be fitted to all brushed motors. Leaving them off is just asking for more problems than you need. If you can't solder a capacitor across a pair of motor terminals then you're in the wrong hobby - try knitting instead.
DM
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A serious question on motor suppressor capacitors: I always fit one across the motor terminals, but have often seen a 2nd and 3rd between each of the terminals and the motor casing. Not sure why, or what benefit as there is effectively no "ground" on a plastic or wooden boat in water. Maybe helping to "RF shield" the casing?
Should we fit one or three ?
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I tend to go with three to cut down on the RF, not sure why it's but it's what he electronics guri told me to do. Probably as that gives each one a connection to the casing and the other thus suppressing the RF interference
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The article "Beat RFI" (March 2006) here explains just about everything you need to know. The capacitors are to reduce both current spikes in the power supply wiring and the radiated RFI from the motor itself. Like the mans says, just do it.
http://www.modelsoundsinc.com/articles.php (http://www.modelsoundsinc.com/articles.php)
DM
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Great article and reading it did give me a face palm moment - earthing via the stuffing box. Considering one of last weeks jobs was checking the earthing points on a minesweeper why did I not think to include this on a model boat?
I am not sure how effective it would be but it has got me thinking
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That article was very illuminating. Many thanks Dave M.
Stresses the importance of wiring layout, keeping RF sensitive items such as Rx far away from RF sources (ie motor etc). Personally I tend to loom wiring in well separated groups, power, control, servos.
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Is earthing to to the shaft tube more to do with galvanic corrosion,than system earthing , I do not now that's why I ask .
David
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Yep, I know there's no capacitors on the motor, I'll whip it out and solder a set across the terminals. I have a stack of Action ones stood standing by ready, so once the second set of painkillers have kicked in, that'll be the first job.
Cheers guys, and well spotted Mr M. ;D
Rich
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I don't think that galvanic corrosion is a big factor for us as our models don't spend that long in water and more to do with contact area to earth to bleed off those unwanted RF wiggles. A lump of aluminium would be better and would also act as a sacrificial anode for galvanic corrosion. Hmmmmm, not got a job on for this afternoon so the mind is going for a wonder
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Cheers guys, and well spotted Mr M. ;D
:kiss:
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Please spare a thought for those of us that try but do not quite achieve. We are not all technically trained or knowledgeable. After a few years of wooden static boats (I can cope with wood) I moved into RC in 2006. A couple of years later I won Bronze at the Beijing Olympics in the 50 Metre 'Running Away from Soldering' event.
As time has passed I have slowly improved my use of the soldering iron, plastics, paint and Superglue but will never achieve the level of some of my friends at the pond.
Let us not forget:
1) There is a difference between lack of ability and laziness.
2) Don't say "All you need". This is on a par with giving the wife a lawnmower.
3) Don't say "It's easy" All things are once they are explained, you have been trained, and you find you can actually do it.
4) At the end of the day it's on the pond, it works and it's my pride and joy.
Encourage us and help us, but please don't put us down and put us off.
Buccaneer
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Is earthing to to the shaft tube more to do with galvanic corrosion,than system earthing , I do not now that's why I ask .
David
Earthing the shaft tube? That sounds like complete rubbish!
I'd love someone to convince me otherwise. Is the shaft a homo-polar generator?
Compared to a motor or PWM controller, anything else will be negligible.
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The RC plane lot never bother with RF reduction much beyond the motor and when their toys go wrong it gets real expensive :-)
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Please spare a thought for those of us that try but do not quite achieve.
Don't say "It's easy" All things are once they are explained, you have been trained, and you find you can actually do it.
Quite.
I've no problem with helping someone who genuinely wants or needs assistance and appreciates it when given. What does annoy me are those folk who dismiss the whole subject with some careless remark like "O, not electronics! It's so boring, and anyway my models work OK without me having a degree in rocket-science". These are generally the folk whose models are rescued most often or who spent most of their sailing sessions with the model on the bank with the top off. I've no time nor sympathy for them, and I don't have a degree in anything!
Plastic
I think you'll find the phrase was "earthing to the shaft tube", which makes a slight difference to your reply.
Jay
I don't think anyone is suggesting that much is necessary in the way of RF reduction beyond the motor because, as Plastic says, there's not much else which comes close as a source of it.
DM
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I wholeheatedly agree with you. Even in the short time I have been in the hobby, most of the people that seem to suffer break downs treat electrics/electronics as a black art and take no care with what they do.
One chap kept frying his sail servos in his Dragonforce65 and put it down to bad servos. Had a look after the third one in as many weeks and rather than the usual 4 AAA packs of rechargerbles we were using he had used a 5 cell LiPo so he was powering his servos at around 7.3v. Asked him why and he said "well more volts = more power but I don't know electrickery"
He is now using the same packs as the rest of us and his servos have stopped dying
Oh he was also runing a speed boat with the motoe and battery exposed and wondered why the motor was smoking a bit
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Even though I am an electrician by trade, I tend to deal with big AC wiggles 440v 3 phase stuff most of the time so some of the electronics is still a head scratcher for me.
How the digital 2.4 Ghz mutiplexed Tx/Rx stuff works I understand enough to know it makes electronics look easy!
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I've spent my working life playing with RF up to 30GHz at powers up to 100KW and solving EMC issues. I'm comfortable with motors and speed controllers interfering with radio equipment.
Fitting ferrites on leads, capacitors on motors, decently sized, short wiring runs and keeping the receiver as far away from the noise sources as possible will solve almost everything.
Earth-bonding to a prop tube? Why? This is not like a mains supply with lots of potential earth loops. There's not a link to anything else to develop a potential difference across.
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The earth bonding on the prop tube did get me.
I can see in theory why but like you said there is no real point as the prime sorce of RF is the motor and dodgy wiring.
The amount of intermitent faults we have at work that are down to bad connections is unreal.
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As Z750Jay says solid connections are the key to trouble free installations,usually you find that the guy who takes time and trouble over the look of the installation will have taken the trouble to make all of the connections sound,a moment spent going round checking the tightness of terminals can save hours looking for faults,Ray.
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:-)) Yep Guilty as charged. I start out full of good intentions and then change my mind so much it all goes to pot. Please do not look in any of my boats if you are of a sensitive nature and allergic to spaghetti. Having said all that I think the termination points are pretty sound its just what goes on in between reflecting the thought process going on between my ears. {-) Graham.
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Earth-bonding to a prop tube? Why? This is not like a mains supply with lots of potential earth loops. There's not a link to anything else to develop a potential difference across.
Might I suggest you take up the matter with David Harrison, the bloke wot wrote it? You'll find him very friendly and informative. You can contact him c/o Model Sounds Inc. I'd be curious to see his reply as this point has puzzled me for a while, but I didn't bother chasing it down because RFI doesn't figure on my personal list of problems.
Dave M
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I wholeheatedly agree with you. Even in the short time I have been in the hobbu, most of the people that seem to suffer break downs treat electrics/electronics as a black art and take no care with what they do.
One chap kept frying his sail servos in his Dragonforce65 and put it down to bad servos. Had a look after the third one in as many weeks and rather than the usual 4 AAA packs of rechargerbles we were using he had used a 5 cell LiPo so he was powering his servos at around 7.3v. Asked him why and he said "well more volts = more power but I don't know electrickery"
He is now using the same packs as the rest of us and his servos have stopped dying
Oh he was also runing a speed boat with the motoe and battery exposed and wondered why the motor was smoking a bit
?
Five cell lipo is 18.8v.
%% %%
Where did he stow it in a DF
Ned
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It was a wierd small one about the same size as a standard 5 AAA pack. Probably was a standard but with LiPo connections.
I was catching up with a mate who is a complete God with electronics(prototype, programming chips and one off electronic stuff business) and he said putting anything more than 6v through a servo is bad.
He is into his model railways and has developed servo based gates and signals with adjustable bounce and drop speeds so has some experience with them.
He will be helping me over the winter with some of strange things I want including a switchable power supply from remote
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I use a five cell AAA in my DF velcro'd to the side if the fin box.
Not had any problems with the winch.
Had a rudder servo burn out nearly melted the hull but the
pond cooled it
Ned
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You have got to love those DFs.!
Thinking on it he may have been using 6 cell packs. I know it was one of those "WTF are you using" times.
They did not look "right". More like a battery pack from a fire and flood detection system on board.
Think it may of been something like this
http://www.modelboatmayhem.co.uk/forum/index.php?action=dlattach;topic=48201.0;attach=138963;image (http://www.modelboatmayhem.co.uk/forum/index.php?action=dlattach;topic=48201.0;attach=138963;image)
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I've just re-read that article again - this is the relevant bit:
Always ground the motor cans by connecting them to your propeller shaft stuffing box. If they are
not connected to anything other than the suppression capacitors, they will act as big fat antennas
radiating the RFI coupled into them by the capacitors! Exactly the opposite of what you want!
Also ground the negative battery supply lead so that you have ONE 0V or ground reference point.
Make sure the propeller end of the stuffing box has a small area without paint to make contact with
the pond water. Although the pond is not a great electrical conductor, it does act as a weak ground
plane, dissipating the motor can RFI signals to ground.
I suppose you could take issue with the last sentence but the rest makes sense. Doing something as simple as grounding two motors and a battery terminal (which may not actually be required) makes more sense than pretending you know nothing about electrics and leaving off suppressor caps - which does matter, and often quite a lot. Anyroad up, I've stood on this soapbox before and so it's time to climb down (again).
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In the three years I have been into RC boats I have learned so much from this forum, and this thread is a shining example. Despite not having had an electrical breakdown in around 250 outings Dave's posting on good RF practice has added to my knowledge and ability to build ships that work as well as they (may) look. We can all learn and improve our skills.
At almost every session there have been numerous breakdowns, almost all electrical in nature. Rescue Tugs have become a necessary part of sailing days.
May I suggest that at regattas a prize may be offered for the most professional wiring job in order to promote good reliable electrical practice. It could make my newly acquired Rescue Tug redundant ( tee hee !)
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Asked him why and he said "well more volts = more power but I don't know electrickery"He is now using the same packs as the rest of us and his servos have stopped dying
Reading specs for servo ICs a few years ago, several quoted a maximum voltage of 7.5 for the chip. Thats a maximum, not a guide or ambition. Above that, the silicon bits tend to break down, whether conducting or not. If they survive that and work, at a higher voltage, with the same load, they will pass more current. Possibly more than they were designed for, so they respond by melting.
A servo will often quote a maximum voltage of 6, this is often a nominal voltage of a battery, and gives a sort of safety margin for the electronic bits. Its actual voltage in service will (should) be a bit higher, but still within limits. Deliberately connecting a battery of higher voltage drives straight through the safety margin, a 2S LiPo will give a nominal 7.4 volts, a fully charged one will be higher, so no wonder that the DF servos were letting the smoke out. Not that theres much scope for untidy wiring in a DF making a mess of radio reception.
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I've seen metal on metal servo rods/arms cause interference on 27/29 Mhz radios from the vibration of the pushrod in the actuating arm, so a rotating shaft in a metal tube probably could cause the same issue, in saying that I have never grounded shafts in models.
It probably would be ideal practice though.
Full sized boats we have put a shaft brush connected to the rest of the bonding system, this reduces corrosion and destruction of bearings (through block to shaft stray currents).
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The only source of interferance with the DF's I have noted comes when they are at a distance, healed over on a tack and half submerged. It puts the reciever under water. As the 2.4Ghz signal can't penatrate water very well it can be a bit lagy as bit of the digital signal are lost as far as I can work out.
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I've seen metal on metal servo rods/arms cause interference on 27/29 Mhz radios from the vibration of the pushrod in the actuating arm, so a rotating shaft in a metal tube probably could cause the same issue, in saying that I have never grounded shafts in models.
It probably would be ideal practice though.
Full sized boats we have put a shaft brush connected to the rest of the bonding system, this reduces corrosion and destruction of bearings (through block to shaft stray currents).
Are you sure it wasn't the brushed motor inside the servo that was causing the interference?
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I've seen metal on metal servo rods/arms cause interference on 27/29 Mhz radios from the vibration of the pushrod in the actuating arm, so a rotating shaft in a metal tube probably could cause the same issue, in saying that I have never grounded shafts in models.
It probably would be ideal practice though.
Full sized boats we have put a shaft brush connected to the rest of the bonding system, this reduces corrosion and destruction of bearings (through block to shaft stray currents).
I've often heard of this, but don't know of any physics that could cause it. Doing a search for RFI and metal to metal rubbing only comes up with model boat sites, so at a guess, something else is having an effect. The same search gives lots of RFI chat, but no mention of metal to metal.
To get into the radio via the aerial, you need something like the radio frequency or a harmonic, say 13MHz (million times per second) for a 27MHz set, and enough power. A motor shaft is unlikely to rotate more than a few thousand times per minute. The servo signals base on 50 per second, so that is a possible entry point, but I am still struggling to see how two bits of metal, disconnected from the wiring, rubbing against each other, are going to generate the kind of energy that will hop into the wiring with enough power to cause problems. A moving shaft rubbing insulation, yes, I can see that, but that is not apparently the problem. It would be nice to have a reasoned explanation rather than accepted folklore.
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You'll get 2 main kinds of interference from a brushed motor - the first is the PWM/ESC drive signal will be made of modulated square waves which are constructed of odd-harmonic sine-waves going up to infinity. 27MHz is actually pretty low frequency these days compared to the speed and rise-times of digital signals.
The second is the sparking from the brushes on the armature. Sparks create all the frequencies in the EM-spectrum at once - visible light is part of that spectrum so you see the sparks but the interference is invisible.
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There's a link here to the Model Boats website where you'll find an article which covers just about everything you need to know - and there's no 'electronics' involved http://www.modelboats.co.uk/news/article/but-i-don-t-understand-electronics/18054 (http://www.modelboats.co.uk/news/article/but-i-don-t-understand-electronics/18054)
Thank you so much for posting the link to that article. I really enjoy keeping the electrics tidy in my models, but know very little about it. That article answers many of the questions I had.
Cheers
KC
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the stern tube / prop shaft thing is called "the rusty bolt effect". two different metals and /or oxides rubbing together can produce significant RF interference. the speed of rotation is irrelevant, it's the RUBBING that sets it up. ground loops are another easy way to mess up the radio reception.
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some good tips in this topic, especially for a "newbie" like myself!
Im a fussy git too, i build PC's & when it comes to the wiring it has to be PERFECT! & tidy :) ...and its gunna be the same for my Tug! :D
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some good tips in this topic, especially for a "newbie" like myself!
Im a fussy git too, i build PC's & when it comes to the wiring it has to be PERFECT! & tidy :) ...and its gunna be the same for my Tug! :D
Good to see other Gunna's still exist. %) %) %)
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lol :D
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I've not built a boat for a long time now (until current one) so I haven't got any pics yet of my wiring in the rc boats, but I have got this photo of my 1/8th truggy build and its wiring if it's of any interest to anyone, I know there is a lot more wiring in boats but I will be doing it exactly the same way with the sheathing etc as it makes it look neat and also helps to protect it should it get caught in anything, this car flies it does around 50mph on 4s lipos approx 60+ mph on 6s
(http://i556.photobucket.com/albums/ss8/saabmania2/12540800_1650670151862737_6379496795247265453_n_zpsf7udldgs.jpg) (http://s556.photobucket.com/user/saabmania2/media/12540800_1650670151862737_6379496795247265453_n_zpsf7udldgs.jpg.html)
(http://i556.photobucket.com/albums/ss8/saabmania2/12507381_1650670138529405_6823110428611162626_n_zpsw6jd6omh.jpg) (http://s556.photobucket.com/user/saabmania2/media/12507381_1650670138529405_6823110428611162626_n_zpsw6jd6omh.jpg.html)
(http://i556.photobucket.com/albums/ss8/saabmania2/12308393_1639699166293169_8682546181890410844_n_zpsgwu0g1ui.jpg) (http://s556.photobucket.com/user/saabmania2/media/12308393_1639699166293169_8682546181890410844_n_zpsgwu0g1ui.jpg.html)
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If you ask the car boys and they'll tell you three .The other two give protection from brush to casing R.F.. They reckon it's caused by chatter of the brushes in the brass carriers. Right or wrong I do not know. It sounds feasible though.I was told this years ago with 27 meg gear so it might be different now. I suppose there is no harm in putting the 3 on though.
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HI All just one picture showing the wiring on my 1/200 scale Missouri. I have to agree I like to see tidying wiring.
Second picture from my latest build
Stan.
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Wonderful!
Seeing the terminal blocks brings up another topic: How to terminate a wire for use in the screw-clamp terminal block?
1. Solid core wire: Just stick it in there and clamp.
2. Stranded core wire: Also OK to stick it in there and clamp... BUT DO NOT SOLDER THE ENDS! Soldering is often done to make a "solid" end for clamping, but it is the opposite... under clamp load, the soft solder relaxes and the joint becomes loose. Lots of fun debugging that issue later on!
The high tech way to do stranded wires is to terminate with a "crimp pin" fitting:
https://www.rcgroups.com/forums/showthread.php?1530964-Wires-to-battery/page2#post40644755 (https://www.rcgroups.com/forums/showthread.php?1530964-Wires-to-battery/page2#post40644755)
You can find the crimp tool and a box of terminals on ebay and elsewhere for not very much. But these put a solid end on your stranded wire, plus give you a little collar to grab on to.
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Sorry guys all my choc block have gone in the bin now using these new connectors. Simple to use strip your cable lift the lever insert cable lower lever job done. The only downside is they all carry the same polarity but you can work out what you need to wire up your project. I have enclosed some pictures. More information if you need it.
Stan. :-)) :-)) :-)) :-)) :-))
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OK then, those do look nice! Series 221 from Wago, can be used as free-standing common connector (replaces a wire nut in an electrical box), or it looks like you have glued them down to the base board? Wago also offer a rail mount clippy thing which could be modified for chassis mounting:
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HI Pat fixed using double sided tape.
Stan. :-)) :-)) :-)) :-)) :-)) :-))
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wire connectors and resistance
https://www.youtube.com/watch?v=Ekh65Jx1Qc0
Interesting viewing
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Just watched the u tube video showing different connectors. There was very little resistance on all the connectors. This will be my second model using the Wago connectors and I have to say choc blocks for me are a thing of the past. The Wago 221 connectors are so easy to use.
Stan. :-)) :-)) :-)) :-)) :-)) :-))
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What the video DOESN'T address is the all-too-common old style RC battery connector, often called the Tamiya connector. These are just bad, and do have high resistance. I believe this comes mainly from the tendency of the female sleeve to loosen up, but also from the cheap tin plating used. Under high load, the I2R losses can generate enough heat to melt the plastic housings! And this opened the door for all the alternate pluggable connectors out there, like Deans (ugh) and Powerpoles (yay) and all the rest.
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With regard to earthing the negative side of the receiver to the prop tube. One thing that has been so far over looked is that the antenna (particularly on 27 and 40MHz) should ideally be a 1/2 wavelength long. This would typically be over 16ft long on 27MHz which would be impractical, so anything we fit to our boats has to be a compromise antenna. On a metallic vehicle we can use a 1/4 antenna with the other 1/4 wave being provided by groundplane created by the vehicle body. If we connect the prop tube to the negative wire of the receiver the lake become our groundplane which increases the effectiveness of the receive antenna. You will probably find that this is unnecessary, and the range provided by your Tx/Rx combination is perfectly adequate for your needs. However, if you want to get the maximum possible range a. prop shaft earth will help.
There are certain advantages when using 2.4GHz. Frequency hopping avoids the effect of interference on spot frequencies and a 1/2 wave antenna is only about 60mm long, which is easy to house within the typical model. Noise sources such as those created by motors and control electronics do not normally extend into the GHz region.
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I have a large tugboat 51” it has a car
Blower motor and a raboesch 400 bow thruster fitted which will run of a 7.4v pack( I’ve been told that it will not run off the 12v battery), I will be using a 12vla battery and have x2 hobbywing speed controllers the radio is a 2.4 6channel. My question is how do I wire it all up? I’m new to rc boating and don’t want to get anything wrong. Does anyone have a wiring diagram of the same set up as me?
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You are already getting this question answered in another thread so no need to piggyback on a 3 1/2 year old thread.
Jim