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[l33_garf]

this is my first post, so Hello all and thank you in advance for any help.
i'm pretty much a complete noob as far as rc boats are concerned, so any help would be appreciated in simple terms

i have a project which i'm researching and this looks like the place to get the answers. basically i have a pondskater orca bait boat http://www.pondskater.nl/english/pondskater_english.htm which is in need of a compete overhaul electrically.


internally there is;
the motor which is:     755 - 7800 RPM unloaded, 9 W max. RF-suppressed

two servos which do the steering and also the bait release door. i cant see any info on them but one has three wires (white, red and black) which does the steering and the other (which does the bait drop door) has three wires (orange, red, brown)

there is a semi sealed box inside which contains the original radio gear which is a printed circuit board the manufacturers info on this is; Radio receiver:    1 stick, 3-channel, 27 or 40 Mhz (24 frequencies)
there is also something which i think is the speed controller between the circuit board and the motor.

now i would rather re-use the servos if possible as there are sort of moulded places for them to 'sit'
the motor if fine also.

but what i would like to do is replace the radio gear and speed controller with something better than whats there at present. (i have had problems with bad signal and overheating)

the battery that the unit runs off is a 6v 7ah sealed lead acid (alarm type)
i was looking into getting some yuasa 6v 12ah replacements, would these be ok? and also need another charger due to charge times.

there is also a three way water proof switch which controls whether the boat is 'on' or 'on with lights' as it has navigation lights around the hull. i presume this could be wired in a similar fashion to the new electrics?


lots of questions i know but i am very grateful for any help!

thanks
Lee

[DickyD]

Come on you geniuses, someone can surely help young Lee here. 

[knoby]

Hi lee, what your proposing should be fairly straightforward. i would imagine the servos will be reusable with other radio equipment , but it would be useful if u could post some photos of the servos & any plugs that are on the ends of the servo leads. That will allow us to see what systems they are compatable with. it sounds as though all u will need is a 3 or 4 channel transmitter & receiver & a speed controller, personally id go for a 40 mhz system as they tend to suffer from less interference. The proposed battery change sounds fine, however u cannot fast charge lead acid batteries, although a 12 ah battery will give u several hours running time, so u may not need to re charge it at the lake side.post some photos of the components & I'm sure the mayhemers will help
cheers Glenn

[wideawake]

Come on you geniuses, someone can surely help young Lee here. 

Oh alright then 

First I'd be reasonably certain that the servos will work with any radio set.   I'd go for a cheap 2.4GHz radio as that way you'll never need to worry about being on the same channel as another boat.   That's important from two points of view.  Not only is it a nuisance if your boat suffers interference but perhaps even more important, you don't want to cause interference to another boat, possibly one you can't even see.    With 2.4GHz that just ain't possible.   

WRT an ESC (motor control unit) you can do no better than consult FLJ on this forum for advice on the best option.
HTH

Guy

[l33_garf]

thanks for the info guys, i'll get some pics posted up a little later, got b+q delivery a kitchen in about 5 minutes and have no where to put the thing at the minute

i like the idea of the cheap 2.4ghz radio gear, i did see something on e-bay which i think would do the trick http://cgi.ebay.co.uk/Acoms-4-channel-digital-radio-control-system_W0QQitemZ170320762825QQcmdZViewItemQQptZUK_ToysGames_RadioControlled_JN?hash=item170320762825&_trksid=p3286.c0.m14&_trkparms=72%3A1683|66%3A2|65%3A12|39%3A1|240%3A1318

am i right in thinking the above would be what i'm looking for, i know it comes with its own servo's but subject to fiding out if mine are compatible (or re-wiring them?)
would i then only need a speed controller?
and will any radio gear etc run on these 6v 12ah batterys? or will i need some sort of transformer?

thanks again
Lee

[knoby]

hi Lee
. the acoms radio gear you have seen would be fine, but this might be worth a look:
http://r2hobbies.com/proddetail.php?prod=rcps61206_61411&utm_source=streamsend&utm_medium=email&utm_content=1813771&utm_campaign=no%20interference%20quality%202.4g%20radio%20system%20available
 
the 6 volt batteries should be ok to run the radio receiver on most systems, but some run on 4.5 volts. don't let this worry you too much as there is a cheap gizzmo u can buy to correct the voltage if required, although many speed controllers also incorperate electronics to to supply the receiver with the correct voltage. we still need to see some pics of the servos to give you deffinate advice though.

sounds like your thinking correctly about the way to go. keep us informed of your progress, especially as im in the market for a bait boat too
cheers Glenn

[l33_garf]

right, i finally have been able to get some pics of the boat. i have stripped it down for the time being to reseal some of the joints and front light etc so it would be a good time to get it sorted if i can.

thanks for the info knoby i did look at that site which seems like it might be the way i go. the only thing is i'm not sure exactly what to buy? and if its water proof/resistant? or if i can make it so?

external front


external rear


internal rear


internal front


front with battery casing removed exposing motor
[/img]

part of the speed controller?


the other part of the speed controller?


the receiver?

receiver and speed controller in box which sits in the front of the boat.


rear servo for controling the bait door


rear servo's connection to wire which goes to receiver.


Pic three shows the steering servo (with a battery monitor which i installed glued on top of it) but this is a pic of the connection.


existing battery


existing hand set

so if they help people decided what the right course of action they would take i will be pleased.

unfortunately there is no info on the motor or servo's at all except whats stated in my first post, so if i wanted to re-use the exisiting servo's and motor but wanted to replace the reciever/hand set and speed controller, what exactly will i need?


and........ one more thing  as this may have to chug along for a good while at a time would i need to look into some water cooling maybe?

one more thing. honest. can i use a small 6v 1.2ah battery as a fail safe? so that if the main battery dies i can, or more importantly the boat can switch over and 'limp' home?
how would i do this?


thanks again guys
Lee

[Ian Robins]

Hi lee,
servo's look ok, black/red/white is standard futaba. brown/red/orange is jr/hitech
anyway   black-     negative          brown
             red  -       positive          red
             white-      signal             orange

this is standard wiring. I would use a cheap 2.4 set and the 6v 12a battery.
do you have a local club. do you want to build other boats,or is the bait boat repair the aim.
I am asking because a local club most proberbly will have someone who fishes and model boats (as I do), they might try to bend your arm to join also.
as far as the motor you need to check the stall current it. this is done by putting a clothespeg on the rotating shaft with the power on and if you have an ampmeter ypu can read the ampage when you squeeze the peg to stall the motor.

pm me for more help as chat is easier than writing text.
 
good luck
ro88o0

[malcolmfrary]

The standby battery is a good idea on the face of it, but liable to create more problems than it solves.  The best bet is to have some means of guesstimating the battery contents.  On my Corvette, I accidentally gained a "hydraulic voltmeter".  I give it full left rudder, and turn the wick full up.  The result is water rising about level with the top of the rail at the stern.  Any lower, its time to come in.  This isn't universal, but there should be some performance parameter thats easy to check with the boat out there and you on shore.

[l33_garf]

thanks again for the replies, i think your right about the extra battery being more hassle than its worth. in fairness the boat will not be making such long journeys really.
it would probably have to make numerous journeys of around 100mts each way.
will have a look at the 'stall' of the existing motor, what will happen when i apply pressure on the peg? will the motor cut out? it wont damage the motor will it?
and what do i do then once i have the amperage of the stall?
thanks again
Lee

[craftysod]

As it is a bait boat and not going to be screamed around,a 15/20 amp esc is fine.
And the 6v batt that you have got will give a long run of time if its just going out to drop bait then back.
Mark

[l33_garf]

thanks again, just having a little look through enay and i think this radio gear would do, wouldn't it?
http://cgi.ebay.co.uk/RC-Plane-Helicopter-2-4Ghz-6Ch-Programmable-Radio-Gear_W0QQitemZ110376470538QQcmdZViewItemQQptZUK_ToysGames_RadioControlled_JN?hash=item110376470538&_trksid=p3286.c0.m14&_trkparms=72%3A1688|66%3A2|65%3A12|39%3A1|240%3A1318|301%3A1|293%3A1|294%3A50#MRLOCATE

but then when i have a little look for a 15/20a esc all the ones i can find are around 60-90a??? would this prove a problem?
ie this one; http://cgi.ebay.co.uk/RC-Waterproof-Resistant-110A-Motor-Speed-Controller-ESC_W0QQitemZ290307740583QQcmdZViewItemQQptZAU_Toys_Hobbies_Radio_Controlled_Vehicles?hash=item290307740583&_trksid=p4634.c0.m14.l1262&_trkparms=|301%3A1|293%3A1|294%3A30

so if i bought the above two items would i be nearly there?
thanks
Lee

[malcolmfrary]

Having a higher spec should not be a problem.  With modern ESCs, generally, what will handle a lot will also handle a little.  Never having heard of this manufacturer, my only comment on the spec is that it might be optimistic as regards current handling, and could be quoting instantaneous (very short term) capability rather than a continuous rating.  The power cables certainly suggest this.

[l33_garf]

would that impair the long term running of the boat? as i said it will probably only be out for a couple of hundred meters at most at a time, but in some instances it may have to make three trips is quite quick succession.

the radio gear says that its programmable via pc, do you think it would be possible to limit the speed this way? as i would rather that the boat was a bit slower than anything and if i get the higher power esc then would i be right in thinking that it would be putting more power through the motor?
Lee

[catengineman]

Control the speed via the throtle stick on the transmitter, small movement = slow speed or full movement = as fast as it can go

if you are just going to poodle about to and fro a drop zone I think you will have hours of run time

R,

[knoby]

Hi Lee
since your motor is only 9 watts, it will only pull 1.5 amps so the wire size will be more than capable & wont affect the long term running.
I like the look of the equipment you have selected, I feel sure it will work satisfactorily. I look forward to seeing the results
cheers Glenn

[l33_garf]

excellent!!! right I'm going to order now and will try and get a video posted as soon as she's back up and running!
thanks for all your help, its difficult when you don't really know what your doing and need someone to say whether what your thinking will work or not!

thanks again
Lee

[malcolmfrary]

if i get the higher power esc then would i be right in thinking that it would be putting more power through the motor?

The voltage of the battery and the motor determine the power taken.  All the ESC does is control the power that is offered to the motor.  If the motor "wants" more power than the ESC can deliver, either the ESC will protect itself bt switching down, or it will protest by dying.
Similarly, having a battery that can deliver a huge amount of current does not mean that it will.  The current going through the ESC is determined by the load (i.e. the motor) and the battery voltage, and the maximum current capability of the battery.
Having a higher voltage battery, now that is a different story.

[l33_garf]

Just started to get my head around the install, and i just have a couple of things i dont understand.

what is this? it seems to be part of the esc or inbetween the esc and motor. do i need to keep it or can i connect the new esc straight through to the motor?

and also i have had a look through the radio gears computer program for setting up the channels. now would i be right in saying that if i want to use one of the channels to switch the lights on for the boat, i will need to use a relay?
the screen that you use to set the channels basically has all 6 channels with a central point and then you can set the maximum amount of output on either side of the central (zero) point if that makes sense.
so on one channel if you push the stearing stick right you get signal to the right on the central point and vice versa.

now the way i have set it is so that one of the switches operates one of the channels and gives full signal ONE Way once switched? would this be ok to power the lights (4 led's and one halogen spot at the front) or would i need this to run through a relay??


sorry again for the long garbled message, but thank you very much to anyone who can help me get moving with this again.
Lee

[stallspeed]

That is a twin-choke motor suppressor,helps with A.M. radios.If you got that R2Hobbies speed control then leave the suppressor in.

The speed control will only handle 20-30 amps average.At 110 amp the blue anodised heatsink and cable are both dissipating 100 watts. 
The speed controller's 110A rating is probably the current which trips the current sensing shutdown.It is a good feature but it means the speed control  stutters or cuts out with current surges of speedboat motors.The choke suppressor helps with that too.

You quoted the motor as 9 watts (which would mean it should not draw more than 3 amp) and asked if changing the esc would help...It wouldn't.Boosting the supply voltage or choosing the optimum propeller for the motor or  does that.If the propeller causes the motor to draw more than half its stall current then its motor output power has already tailed off due to over propping.
If the motor is drawing 3 amps you can up to 12 volts.The R2 speed controller would probably work better if the voltage was above 7.
If the controller has no maximum throttle adjustment and you are overpowered then you sort that by by using an even smaller prop or on the transmitter by limiting the 1-2 millisecond range to,say 1.25 - 1.75.

[malcolmfrary]

The device in the picture is a pair of chokes intended to stop interference coming from the motor getting back into the electronics and upsetting them.  Some motors are better at generating interference than others.  In a more normal installation, we would not fit the chokes, but use capacitors to do the same job.
The channel outputs on the RX can only handle very low power levels - they always need something to translate the information into actual useful work.  In the case of lights, probably a latching switcher.  This could incorporate a relay, it could be a fully solid state devive, the choice is yours.
Now the people who have multi-channel radios will tell you how to use them.

[l33_garf]

thanks again for the info.

from the sounds of it a latching switcher would accept a signal then stay in the 'on' position until the apposing signal was received? is that correct?
if so the way that i have programmed the controller using one of the switches to only provide a full signal one way wouldn't work would it? as when i switch the switch off it just kills the signal back to the zero rather than giving an apposing signal. (not sure if apposing signal is correct really)

with a latching switcher would it be better to have the lights operated via the right hand (unused at present) control stick? therefore being able to give signal both ways?

if i did use the channel with the switch on and just used a relay, would it matter that the hand set would have to be continually sending the 'lights on' signal from the switch? would this wear the battery down in the hand set quicker?

again thanks for all the help and sorry for the never ending questions i just want it to work first time (for once)
Lee

[malcolmfrary]

The simple, down and dirty way is to use a push-push switch worked by a servo.  Push for on, push again for off. I leave the programmable TX info for those who know about them.

[dougal99]

I use an Action switcher which can be configured to latch (stay on until switched off) or stay on only while a signal is present. It works on one channel but only at the extreme so could be used on a y lead off another function.

see here

http://www.action-electronics.co.uk/pdfs/P44A.pdf


HTH

Doug

[l33_garf]

thanks guys, getting there slowly but surely. i am really struggling to find a water proof power switch though, is there a recommended online retailer that sells stuff like switches and cable etc? i have looked through a few but cant seem to find a power switch?

thanks
Lee