Forum
Help with vintage rc.
I wouldn't want to stop people running old kit - far from it! I have a single-channel 1962 Macgregor with a Kinematic which I use occasionally - when there's no other 27Mhz around. But you need to be aware of the issues.
With this sort of kit (and even worse for valve systems) you will find that summer is for sailing, and winter is for repairing. Here is the start of a thread on RC Groups with myself and Taurus Flyer sorting out a
capacitor
problem on the TX - which meant reverse engineering both the Rx and TX....
https://www.rcgroups.com/forums/showthread.php?2609824-Reverse-engineering-and-repair-of-a-vintage-Metz-Mecatron-single-channel-radio/page32
One example of problems you may encounter is that the caps in old kit tend to die, particularly if the equipment has not been used for many years. Electrolytics, in particular, suffer. See
https://en.wikipedia.org/wiki/Electrolytic_
capacitor
#Failure_modes,_self-healing_mechanism_and_application_rules
You can sometimes reform the electrolytics by turning the TX and Rx on and leaving them powered up for a day or so. it's tricks like this that you need to be aware of if you are going to run vintage equipment....
5 years ago by DodgyGeezer
Forum
All hooked up, nowt happens...
Hi Steve, I have the same problem with the ESCs in my HSL. They are cheap Chinese car models and can be a bit tricky to get into reverse quickly. I have found that either waiting a few seconds in neutral before trying reverse, or going to neutral and flicking the throttle forward a few clicks and back to neutral quickly (in .5 sec) usually sorts it. I think it may be that the motor stops somewhere that the cheaper ESCs can't detect (bit like an old car starter that hits the bald spot on the ring gear and you have to jog it a bit) so you have to move it slightly for it to 'see' it (maybe the
capacitor
s also). Brushed ESCs don't have that problem as the brushes are in constant contact, rather than relying on correct positioning in Brushless motors. You will also find that some Chinese motors are not timed/wound correctly, and you can feel weak or 'floaty' spots between certain magnets which may also cause a problem. Perhaps trying a higher or lower ESC timing by 1 step either way might help if you have that capability.
if it works by just flicking the throttle method, you can just slow down as you come in and take you time finding reverse in a scale like manner (remember the PT109 movie where they went through the shed on the wharf) You can also try swapping the other pairs of wires on the motor (same direction but different pairs). if you are still not happy then it might be time as Doug said, for a better ESC with instructions. Get one which has all the programing features, (fwd, rev , timing, auto batt detection (lipos or NmH etc) starting mode- ie soft,hard, brake etc) this will give you plenty of options for adjustment. Doesn't have to be a marine one, a good known brand car/buggy one will do and if you have any heat problems you can always put a mini fan on it. Water cooled marine ESCs are really only for high amp high speed setups. My 36"HSL has 2x 30A car ESCs running 2x 28/45 2000kv water cooled motors and ESCs never get even warm. Pictured are the ESCs I am using from HK which have an output plug for a fan if needs be. The 3rd pic is the brushless ESC types (EBay, AliExpress) I am using, which have no problems with reverse transition (see vid section re Thornycroft MTB maneuvering) also the HSL vids to give you an idea of how these brushless ESCs perform even with the minor reversing problem. Hope you get it sorted.
5 years ago by jbkiwi
Response
Internal wiring & bottom skins
Hi Rob, the Police Launch is coming along nicely. I see that you have long leads from the battery to the ESC. The general rule is that these leads should be kept as short as possible to minimize voltage spikes caused by the fast switching currents and the inductance of the leads. Brushless ESC's have large
capacitor
s, often visible at the end to absorb the transients. You may well get away with it but the life of the ESC could be reduced.
Hope your Xmas goes well, Alan
5 years ago by ukengineman
Response
HMS BRAVE BORDERER
Hi Rowen,
You don't need
capacitor
s at all, and certainly not in series with the wiring.
Whereas I can heartily endorse all that jbkiwi says about the possibilities of modern TXs, I've only scratched the surface of what my Spectrum and Turnigy sets can do, I can see no justification for the extra
capacitor
s on ESC leads.
The length of the wires inside a typical model can not have a significant effect on the total resistance.
Given a typical resistance of 1m of copper wire with ca 1mmΒ² cross sectional area of 0.02β¦ (less for larger gauges) it ain't gonna make a happorth of difference whether you have 4" (10cm) or 40". Maybe a little more warmth but the
capacitor
can't change that.
I also can't see where the spikes he mentions should come from.
Also bear in mind that the ESC does not apply pure DC to the motor but a pulse train with a pulse repetition rate of around 8 to 10kHz. That's why the motors whistle and scream.
Adding
capacitor
s to this could distort the pulses or reduce their peak value.
If the ESC is so bad that it produces big spikes when the pulses are switched on or off (which I doubt theses days) then junk it and buy a decent one.
On no account fit a
capacitor
in series with the wiring, unless it is a special Coaxial
capacitor
, which are very big and relatively expensive. See pic.
I've only seen them on large electric motors on board ships where the much higher currents and longer cable runs involved than in models may play a role.
A very small value
capacitor
, in the picofarad range might help to short out any potential high frequency RF interference but I've never experienced the need to fit them. in this respect it could be more important that the length of the cable is not close to the wavelengths typically used by RC sets (12.5cm at 2.4GHz) so that it does not act like an antenna.
Cheers, Doug π
jbkiwi have looked at the link you posted but I'm not convinced considering the small lengths we use in our boats. Yes there will be some overshoot spikes in the pulse train but so severe as to damage anything is in my opinion highly unlikely, given a decent quality ESC in the first place.
Something else on that link just occurred to me. There is a pic of what looks like electrolytic (polarised)
capacitor
s between the wires. This is fine for aircraft ESCs which only run forwards, and thus produce positive going pulses. in our boats with reverse the pulse will switch over to negative going. Which after a while could have an explosive effect on the electrolytics. it blows the cans off and produces an interesting snowstorm effect. Good party trickπ but maybe not so super inside a model boatπ‘
IF you do fit them to a reversible ESC be sure to use tantalum
capacitor
s which aren't so fussy.
5 years ago by RNinMunich
Response
HMS BRAVE BORDERER
Doug,
Am using the HobbyKing 50A Boat ESC 4A UBEC along with their programming card. The diode explanation makes sense so will fit one.
jbkiwi
My battery -ESC and ESC -motor wires are short, probably around 4" each. The addition of
capacitor
s as suggested is intriguing as have never heard of it before. Think it is easier to keep things together in a boat, whereas with an aircraft pitch trim becomes a factor. Am using 2S batteries with a 50A ESC, with the motor max current of 30 A. Have you any idea what size of
capacitor
I should use?
The Tx/Rx combinations are almost infinite as the ESCs are programmable too. Just wish the ice would go so can experiment!
Thanks both for your help, with this hobby you never stop learning.
5 years ago by Rowen
Response
HMS BRAVE BORDERER
Thanks jbkiwi and RN in Munich for your suggestions:
Have never used Ali Express, those components look interesting. Will follow up. I have used a battery alarm of the type suggested and it does work well. Have a couple for use once back on water.
The rule about adding a
capacitor
into the ESC circuit is new to me. Have ferrite rings fitted so will now explore adding
capacitor
s too. Are these is series or parallel with the wiring?
The relays are not used with diodes or any electronic gubbins. Wanted to make the circuit as simple as possible for a Mechanical Engineer, so used one separate relay per ESC. The relay operation is controlled by a RC switch off another Rx channel. it seems to work. Am aware of the back feed possibilities and hope to have avoided them with the separate circuits. Appreciate any thoughts though, can add diodes if necessary.
Am using a new FLYSKY 10 Ch. Tx/Rx on this model which opens up a host of programming opportunities. Am experimenting with various features such an the interval between Fwd/Rv also limiting ESC response. As am now using the brushless motors essentially in unison, also toying with controlling the 2 x ESCs on a βYβ lead on a single control.
Much to think about, pity our winter has arrived early and the pond has been converted to a skating rink.
5 years ago by Rowen
Response
HMS BRAVE BORDERER
Rowen, here are a couple of things that may be of use to you (and others). The battery alarm will save you worrying about running out of steam as they can be set to beep at varying voltages to warn you of low battery, just put one on each batt balance lead and when one goes off (when an individual cell drops below the set voltage) it means start heading back. These can be picked up on Ebay for a few dollars. I use them on my planes as well and are audable from around 100m (these twin horns are the best) Secondly, re your ESC switches, these electronic switches (AliExpress) are great for this sort of thing (as long as you have enough aux switches on TX ) You can link them with a Y cable to work together or use them independantly for anything, (lights, pumps etc, - they can be operated by TX rotary switches as well) The ESC and 2000kv motor (HK) are the ones I am using in my ASR model and will work smoothly down to a crawl, the purple 1980 kv seems to have superseded these but I think they will be as good. The props are from Ali Express and are resin and available in L and R hand, are only a few bucks and perform perfectly while looking quite scale(ish). I painted them with an acrylic bronze which seems to have stayed on pretty well. Model weighs 2.8kg and will run at more than 10mph flat out with this set-up (using the 26mm L+R) props) which is silly speed and that's with 2x 2s 2200mah lipos (which will last till you get sick of it and still have 60% left)
I was just looking at your Daman set-up and noticed the wiring method from the batts to the ESCs. You might want to make your batt to ESC connections direct to your ESCs (as per original ESC lead length)as your
capacitor
s may get a thrashing (spikes) due to the extra length/ resistance you have there. There is a general rule that you don't lengthen the batt to ESC wiring without adding a 220mf
capacitor
of same voltage as the ESC for every 4"of extra wire length (ESC to motor - not so much). Might want to check this out in case you fry your ESCs You probably have thought of this but thought I'd mention it, 'just in case' Might help with your modulation as well.
Have chucked in a vid of the HSL manouvering (first trials so wasn't perfect) and also the MTB (brushed) which I have just converted to a twin system (was twin but single Electronize unit) plus a sound unit. You may know that you can use as many RECs (bound to the same TX) for various purposes on the same boat (have run 2 boats together from the same TX) Might get you round the mixed brushless/ brushed problem with a bit of thought. Have you thought of changing your old HK silver 6DF TX to twin throttles, it's a piece of cake(as is the TGY 6x), just remove the aileron/rudder centering spring and make a friction plate as per throttle stick, and use the elevator channel as your other throttle. Set your ESCs and you can then use a twin system giving you perfect control. Saves a lot of hassle.
5 years ago by jbkiwi
Forum
All hooked up, nowt happens...
You're as BAD as me Boaty π but I had a Rover 2000 with fully reclining seats back then - no problem π
Re 3 wires on a brushless. Simply put, this is analogous to a 3 phase AC motor (such as used in bathroom extractor fans etc).
If you apply a single phase AC voltage to an AC motor it just twitches backwards and forwards in the same place as the voltage crosses from the positive to the negative half cycle. Thus 3 phases are applied giving 3 'shoves' in sequence to keep things moving. A starter
capacitor
is also needed to give the motor a 'belt' to shove it off.
Similarly with a brushless:
the ESC senses where the motor armature is in relation to the magnet poles and applies a DC pulse to the next armature coil in sequence.
When you shove the throttle up the pulse width lengthens applying a longer shove and thus more energy and speed.
Pulling the throttle back with a reversible ESC just turns the pulse train upside down so that negative DC pulses are applied to the motor, reversing the magnetic field created in the armature and thus the rotation.
Simple really.
It's the sensing and timing done inside the ESC that's the tricky bit, which is why we had to wait about a hundred years from the invention of the AC motor (Nikolai Tesla) until we could use them in models - thanks to micro-electronics.
Here endeth today's seminar ππ
Happy brushlessing Folks, cheers, Doug π
Hmmm, perhaps that's why electric toothbrushes use brushed motors! ππ
5 years ago by RNinMunich
Forum
Taycol Supemarine Resurrection
Hi Boaty,
The Taycols have fascinated me as well, ever since I dug the Target out of the Sea Scout my Dad built in the early sixties. I blogged my renovation of that and the conversion to run with a modern RC system and presumably that, and the converter boards I built for Martin (Westquay), is what triggered Colin to ask me to have a look at his Supermarine.
How could I resist!? π
The 'smell of something electrical' is the ozone gas caused by the prolific sparking of the Taycol metal to metal brush / commutator combination.
The other source of Ozone is on the coast wherever there is a strong surf!
I agree, a nostalgic smell, which unfortunately disappears when the converter board is attached to make it run with a standard brushed ESC. The diode bridge kills almost all the sparks. 'Almost' so the usual suppression
capacitor
s are still recommended. 0.1Β΅F across the brush terminals, 0.047Β΅F from each terminal to the motor can, or frame in this case. Earth to prop shaft tube as well if possible.
The motor may not disturb the on-board electronics of your own boat, if using 2.4Gig, but could still affect anyone nearby using 27 or 40Megs.
The power density of spark transmitters (e.g. unsuppressed E-motors, peaks in the upper HF bands and diminishes to almost zilch in the UHF bands. I.e. approx 30 MHz upwards.
Like me and other submariners for instance; 2.4Gig is useless for subs cos it don't go underwater. Cheers, Doug π
But here!
BTW Boaty: where are the pics of your Avanti? Harbour posts without pics are pretty dead π€ Cheers, Doug π
6 years ago by RNinMunich
Forum
Launch ELAINE,
And what a
capacitor
. Big enough to have come from a washing machine of that period. Maybe it did. The whole thing looks like a lashup. Used whatever would work.I had loads of old valves but noone wanted them so dumped them. Some of them were More modern ones to replace the DCC90 but 1/3 or less the size. Those relays look like the old G.P.O. type. We got them from a Gov't surplus shop for buttons. Those were the days. Sometimes we added in an R.A.F r/f amplifier without the case. it increased the range but don't ask me now how we wired them in. There were 4 connection points on the casing which accepted a multi-plug connector secured by a threaded ring. Nice bit of kit til we got our hands on them.π
6 years ago by onetenor
Forum
Launch ELAINE,
OK twigged it!
The 'second' bottle is the end of the
capacitor
, still in the box.π€
Ciao, Doug π
6 years ago by RNinMunich
Forum
Launch ELAINE,
Appreciate your help, apparently only the large
capacitor
and 1 of the relays is suspect. The radio magicians from camp it would be possible to replace them but it would lose its value as an exhibition piece.
Cheers Colin.
6 years ago by Colin H
Forum
Launch ELAINE,
Well today the radio specialist guys checked out the reciever for me, apparently it would need a new
capacitor
, a 90 volt and a 2 volt supply. Not really possible in such a small boat. So I've decided to use it for my vintage displays. The boat itself will be renovated and fitted with an electric motor, possibly a 600 as I have a couple in the spares box. Still looking for a way to remove the kitchen nozzle system. The motors that operate it are working so hopefully should be controllable by modern rc gear. Might need Dougs help designing a system I can build. BTW the Hull and cabins and deck is constructed from 1/4 inc ply. Bit heavy but good and solid except for some of the frames are very soft and crumbly. Will start a resurrection blog soon. Cheers Colin.
6 years ago by Colin H
Response
Range Safety Launch?
Hi Neville,
that far forward I would definitely look for some hull damage forward; crack in a seam or delamination? When you find it clean off all the paint around it, seal it with EzeKote and repaint. inside fill either side of the keel in that bay with resin. Check also the skin joints around the chine.
Re motors; I don't see any suppression
capacitor
s π² and the motors (or the one I can see) are mounted very high giving a very steep shaft angle! Will tend to push the bow down at speed instead of planingπ€
Ciao, Doug π
6 years ago by RNinMunich
Forum
Martin's Taycol Conversion Boards
OK, in chronological orderπ
No! The Wattmeter has to be spliced into the cable between source (i.e. battery) and the load, ESC and motor. As shown in example 1 in the instruction extract above.
BTW 1: if your Wattmeter comes with instructions in Chinese Unwinese (Misstoodifold in the under number 29sπ) then use the above.
Despite it's name it's primary use to us is to tell us the current the motor draws so we can select appropriate fuses. it will also tell you the mAh you've taken out of the battery, or put in when on charge.
As far as I'm concerned the actual Watt measurement is relatively useless, except perhaps for 'Bragging Rights' π
Speccing the ESC should be done by checking the motor current specs and adding a good margin for safety. if no specs available use the Wattmeter to tell you the current drawn at full voltage from a DC source. if possible under load in the bath. Hang on tightπ² That only works for BRUSHED motors of course! Then use an ESC capable of twice the measured current.
BTW 2; if you want to use your 27 / 40Mhz TXs you will definitely need the suppression
capacitor
s on the motors, despite the partial damping effect of the rectifier, to reduce interference to your own radio.
Fuses; I'll put 15s in to be on the safe side. if the Wattmeter / Ammeter measurements indicate less than 10A max then change fuses to10A and use a 20A ESC so it has some reserve. Or is operating within it's true capacityπ
Cheers, Doug π
6 years ago by RNinMunich
Forum
Spektrum, new, useless...
Hi Martin,
You do like living dangerously don't you!? π
Why don't you ever buy anything from the same manufacturer to be sure it will work, or have the chance of regress if it don't!
Anyway, since you've been an' gorn an' dunnit -
Ignore the PPM, that just means Pulse Position Modulation.
A type of TX modulation waveform that you don't need for the Spektrum TX. Forget the Stat as well. I suspect that that should be SAT for a Satellite RX. No that don't mean you can watch telly on itπ it's just a connection for a secondary RX. Never ever seen one in action!
The others are the usual aircraft / chopper functions in a particular TX Mode, so you can ignore the labels. We can use the channel outputs for whatever we want in a boat. Attached is a description of the binding I found in an RC flight forum. A little bit Chenglish but clear enough I think.
Your Simprop 18A job should be more than man enough for your Supermarine. I don't expect that it will eat more than 10 or 12Amps.
Put a 15A fuse in the + supply between motor and the mod board that makes it run ahead & astern; i.e. the + output of the bridge rectifier. That will protect the motor coil and brushes.
Put another in the + from battery to ESC to protect the ESC and rectifier. Rectifier should be rated at least 20A peak forward current. 30A might be better in case your Supermarine is hungry!
In that case use 20A fuses.
10A was enough for my little Target π
See attached pic for the mods to the Supermarine.
Connections from the rectifier board to motor are-
+ and - of the rectifier go to the brush terminals.
Of the two ~ (= AC) one goes the field coil.
The other goes to the - wire from the ESC.
+ from the ESC goes to the other end of the field coil.
If the motor runs wrong way (with respect to throttle stick) just reverse the brush wires as usual. Don't forget the suppression
capacitor
s, you may not need 'em due to the spark suppression by the rectifier but ... JICπ
Bon chance mon ami π
Cheers,Doug π
6 years ago by RNinMunich
Response
Seeing the light
Hi Peter, Glad it works at all! π
1. the
capacitor
on pin 5 has no effect on the timing circuit.
It's only there to stabilise the 555 chip and stop it 'going off it's trolley' at higher frequencies π it should be 10nano Farad, not micro Farad.
It's job is to short any stray high frequencies to ground.
2. Attached is a table of results I would expect for the values you gave me, and various values of the pot R1.
The duty cycle (%age On time) should vary between 50% and 95%.
Max on time 1.4sec at R1 = 200K. But Off time of 32mSec you'll hardly notice.π€
3. R2 is way too small at 4.7k compared to the 200k pot.
I warned you that it needed to be similar to the pot to make the adjustment less sensitive. The low value is also the reason why the Off time (discharge time) is so short at 32.62mSec π²
4. The timing cct is governed by R1, R2 and C.
Pic 2 shows the output waveform switched between Vcc 6V and 0V-
Increase C to increase the whole period (T1+T0) (reduce the frequency).
Increase R1 to increase High Time (T1), without affecting the Low Time (T0).
Increase R2 to increase High Time (T1), increase Low Time (T0) and decrease the duty cycle.
5. Your 180Ohm resistor is about right for an LED with 2.5V Forward voltage drop and 20mA current. if the LED actually wants 30mA you can go down to a120Ohm.
So, how much is 'increase the on time a little'?
What cycle frequency do you want? How long On and how long Off?
Since you are 'Breadboarding' you could just try plugging in different fixed resistors for R1 (instead of the fiddly pot) and R2.
Pic 3 shows results for R1 = 47k and R2 = 100k, C = 10uF.
About 1Sec ON, 0.7Sec Off.
Cheers, Doug π
6 years ago by RNinMunich
Response
Seeing the light
Evening Doug.
I have made up a couple of circuits. They both work well. I have fitted the variable resistor to your design and it works really well.
The circuit components are as follows. R1=200k variable. R2= 4k7 resistor. Chip= 7555 CMOS.
capacitor
after R2=10uf.
capacitor
at pin 5 = 10uf. Single blue LED is 20mA with a 180r resistor. Battery voltage 6V.
I have some strange results. The variable resistor works well but strangely, if I disconnect the
capacitor
at pin five, there is no effect to the flashing light at all. it still works well. There is also no effect if I increase or decrease the value.
I am happy with the results but would like to increase the on time a little. Please can you tell me which component should be altered and whether the value rises or falls.
Thanks for your help.π
6 years ago by MouldBuilder
Response
Seeing the light
Hi Doug. Still waiting for some components to arrive so that I can try this circuit on my breadboard. One question though. My trimmer pot has 3 contacts. I assume that the middle one is the wiper and the other two are the resistor. Do I connect pin 2, the middle one, to V+ and the other two in line to pin 7. Could you suggest values for R1 and R2. The
capacitor
in series with these, would 100uf be enough to start and if not enough, how many additional uf is required to make a difference. By the way, the chip is a 7555 CMOS. Thanks.π€
6 years ago by MouldBuilder
Response
Seeing the light
Hi Peter, attached the pinout of the 555 and a circuit for an astable oscillator giving a square wave output suitable for a lamp flasher.
Frequency (flash rate) is defined by R1, R2 and C. The bigger the 'C' and/or R1 the slower the rate. R2 defines the discharge rate.
Therefore the ratio of R1 +R2 to R2 defines the ratio of On / Off times!
A little experimentation needed. You can put your pot in place of R1 for some flash rate (F)adjustment.
F=1/Cx(R1+2xR2).
If you want to get really 'snazzy' you can use the 555 in monostable mode (pic 3) and use the pulse output from an RX channel as the trigger input.
You may need to add a series
capacitor
and a resistor to ground (try a 10K to start with) to slow the trigger down a bit and experiment with the
capacitor
, a small electrolytic or Tantalum. it helps if you have an oscilloscope for such experiments! A cheap analogue 100Khz or 1Mhz job would do.
The astable version is simpler, just put a remote controllably switch e.g. transistor switch board or, even simpler, just a microswitch mounted on a servoπ) in series with the Vcc (+ supply) to the timer chip.
It takes longer for the first flash after switch on to occur as the cap has to charge up from 0V to 2/3 Vcc. After that only from 1/3 Vcc to 2/3.
Ratio of ON time to OFF time depends on R1 and R2.
ON=Cx(R1+R2),
OFF=CxR2.
Happy soldering and Flashing π², cheers, Doug π
PS: are your 555s bipolar or CMOS? Makes a difference!
Bipolar types only drive the output to Vcc-1.7V.
CMOS types drive the output to full Vccπ
PPS: One other point! is your 'Blue Lamp' a bulb or an LED?
If an LED you will need a resistor in series with the output to limit the current to a max of about 30mA. Start with 1KOhm, if too dim go down to around 220/270Ohms.
6 years ago by RNinMunich
Response
More running in at Bournville.
Update from MFA Como The motors, as they are, sufficiently comply with CE regulations for electrical emissions. However, sometimes with radio control you may need the extra suppression to stop radio interference.
Initially try one
capacitor
across the terminals, this is usually a 0.22uf.
6 years ago by Novagsi0
Response
More running in at Bournville.
The motor is only a few months old, bought new for Howe's models. I've heard of old radio caps going dry and I means after 40 years of service, since the brother in law repairs old radios and juke boxes. But not
capacitor
s after 16 weeks, the motors only done 3 or 4 hours of service in total. I've added an additional cap across the terminals. I also had a reply from the speed controller company they said to check the fail safe on the transmitter which incidentally is working to kill the throttle channel as its a fly sky intended for a (plane).
6 years ago by Novagsi0
Response
More running in at Bournville.
That's an odd thing to say. They don't last for ever,especially if they are not used. What about being stuck in shops or wharehouse's and not bought for years. They wouldn't be any good then when you buy them. Surely
capacitor
s don't have a shelf life. I could understand them breaking down when constantly being used.
6 years ago by BOATSHED
Blog
MFA 850 motor
On closer inspection of the MFA850 motor I can see 2 caps in side the motor connected between the terminals and the motor body / can. The only thing I can add is an additional
capacitor
of 0.047uF connected between the terminals as belt and braces. Otherwise move the aerial and hope no more paint accidents happen.
6 years ago by Novagsi0
Forum
1960S Taycol electric motor
Hi All. all good advice for the normal brushed motors in cans with carbon brushes. But the Taycol is a totally different animal! it has no carbon brushes. They are simply stamped thin copper or phosphor bronze sheet.
Contrary to carbon brushes they need OILING to reduce the wear and sparking!
Attached are some pics from my Taycol Target renovation and modification to graphically illustrate the point. Pic one 'Before', pic 2 the new phosphor bronze brushes I made.
BTW: don't EVER put oil on your carbon brushes! Try it if you're curious, but then buy a new motor or try to find some replacement brushes π
If you run the Taycols dry they wear the brushes through until they have a hole in the middle and spark like crazy Pic 1. You can put what
capacitor
s you like on, you'll still get interference especially at 27MHz.
Pic 3 shows the effect this has on the commutator. Pic 4 shows the renovated commutator, there was more 'meat' left on it than I expectedπ
Pic 2 shows the new brushes I made from phosphor bronze sheet.
The spark energy density spectrum peaks in the HF band (e.g. 27MHz!) and falls off rapidly in the VHF band (30MHz upwards) to virtually nothing in the UHF and Gigahertz bands. That (and the frequency hopping process the 2.4Gig sets use) is why they don't suffer such interference.
BTW: as a matter of probably no interest π most sets only use 16 or 32 of the 85 frequencies available in the band! π²
The
capacitor
values given above are unusual and will only work with a 'canned' motor, which the Taycol ain't! The norm for a standard canned motor with carbon brushes would be 0.1Β΅F across the terminals and 0.047Β΅F from each terminal to the can, which with a Taycol you ain't got!
Earthing to the prop shaft is also a problem. Where do you connect the wire? There's no 'can'. Frame? That's paxolin! try soldering to laminated iron core if you want. Good luck. Won't achieve much even if you manage itπ€
Once again I ask which Taycol you have, as the construction varies and hence the suppression methods / connections.
Imperative is the condition of the brushes and commutator to minimise the intensity of the spark generation in the first place!
Also important is how you are controlling the speed: also 'Period' with a Bob's Board or resistor coil and servo driven wiper??
These can also be spark sourcesπ‘ Never mind wasting precious battery power as heatπ²
If you want to convert to using an ESC with proportional forwards and reverse, which Taycol field motors can not do without reversing the polarity of EITHER the field coil or the rotor coil but not both, I can show you how.
I did it with Dad's old Taycol Target, see my Build Blog 'Sea Scout Jessica'. Pic 5 shows my Taycol target dismantled, before the renovation.
Pics 6 & 7 the reassembled motor after renovation.
Pic 8 shows the motor voltage across the terminals before the conversion, complete with gigantic sparks of amplitude 100% of supply voltage.
Pics 9 & 10 show the waveform on the terminals of the modified motor at slow and fast speeds, hence different pulse width; broad pulse more speed, narrow less speed.
BUT: virtually NO SPARKSπ and no
capacitor
sπ
Trick is in the bridge rectifier used to connect the motor to a standard brushed ESC. The diodes in the rectifier suppress the sparksπ
Pic 11 shows the wiring 'lash-up' I made to test the motor before mods. Pic 12 the PSU used for the tests. ESC is a 30A Graupner Navy.
Instead of TX and RX I used a simple servo tester to drive the ESC.
Scope used speaks for itself! As expected speed control was possible but no reverse.
Media File 1 Vid shows the renovated motor running but unmodified, complete with sparksπ‘ Sorry Dave_M, I can't upload the ozone smellπ€
Media File 2 shows the scope display of the unmodified motor test, complete with the sparks that cause the kind of interference you are suffering from.
Wanted to add the final vid showing the clean waveform after the mods but it's too big for the site: 30MB max and the vid is 47MB π
Penultimate pic shows the circuit used to connect to a standard ESC (Brushed!) for full remote control proportional forward and reverse.
Final pic shows the test set up for the fully modified motor. Note 4 connections: 2 to field coil, 2 to brushes (i.e. rotor coil) as per circuit diagram of the interface board.
Have fun, cheers Doug π
6 years ago by RNinMunich
Forum
1960S Taycol electric motor
Could try general suppression
capacitor
s arrangement, I have also seen the can or frame of a motor connected to earth via a wire soldered to the brass propshaft.
You could shield the motor by enclosing it in a metal box, be careful not to short circuit anything, similar to Faraday cage .
6 years ago by CB90
Forum
Submerine
Hi Tony
You have not said if the model performs normally as soon as you are back on the surface, but if it doesn't I have the following suggestions.
I like Mtronic and have used them in many of my models but they can (as do several other manufacturers), in the event of a power wipe out, go into reset mode and this can result in you losing the fwd/rev function. The ESC has reset to minimum throttle stick down and only one direction as a result. I guess its pot luck whether this is fwd or rev but rev seems to be the most common.
If you replace the BEC with a battery to power the rx this may help. You do need to disconnect the red lead from the ESC to the rx and still need to switch on the esc after the rx.
If it has reset you need to reset the controls whilst the two lights are flashing by pressing the ESC button and moving the sticks to their full extreems.
You will need to have
capacitor
s across the motor terminals and also between each motor terminal and the case.
Your rx connecting wires and aerial should be as far away as possible from the high current battery wires and the wires from the motor to the ESC.
Doug has already suggested re rerouting the aerial and as you have this suggests a weak signal.
Have you done a range check with the Tx aerial down? You should be able to have control from at least 20' without any interference?
Please let us know how you progress.
7 years ago by Dave M
Forum
Twin motor control problem
Good, get rid of the mixer until the basics work! π
I'm pretty sure the snag is more in the antenna position and/or motor suppression - duff
capacitor
? - causing a Failsfe condition.
Good luck, Doug π
7 years ago by RNinMunich
Forum
What motor have I got?
Right, I hope this works! The can length is 57mm,can diameter is 35.7mm and the shaft diameter is 3.18mm. Photos are attached,fingers crossed.the motor with the impeller,if that is what it is, also has a bronze(?) front bearing, different to the other two. in one of the photos of one of the terminals there is a small wire coming out from the inside, matched by a similar wire on the other terminal. Does this signify that there are internal
capacitor
s fitted? What does the small red plastic thing on the rear signify?
Chris
7 years ago by octman
Forum
Servos & motor having a wobbly
Hi Doug
I well remember these chokes and that
capacitor
. I do believe modern thinking is to wrap the low current wires to the ESC round a circular choke, there are never any chokes in the supplied ESCs motor leads. I do recall advice on one of the forums regarding not putting any inductance in the motor leads, not sure if it was Electronize or Mtronic who gave the advice. They both adopted high frequency pulses for control a few years ago and there was lots of discussion as people upgraded their old ESC to a new one. Chokes were quite common in the past but the technology was vastly different to that used by modern ESCs.
Are you sure the interference is from the motor? I had a very similar symptom with a faulty servo, very similar to that Eric is using. I have asked him to unplug the servo and see if the problem goes away. So far I have not had a reply so can only guess what might be the problem.
Cheers
Dave
7 years ago by Dave M
Forum
Servos & motor having a wobbly
Hi Eric, yes there is - put two chokes with ferrite cores in the leads to the motor. Mount them as close to the motor as possible with a 0.47 uF
capacitor
across the output ends (closest to the motor).
See attached pics of such installed in my Type IIA submarine.
Not quite as good as direct on the motor can but , 'better than a slap in the face with a frozen haddock' π
Your local model shop (or Maplins? etc) should be able to supply the chokes. They are also used in the auto industry to suppress ignition interference on car radios etc. Cheers Doug π
7 years ago by RNinMunich
Forum
Servos & motor having a wobbly
Thanks too Doug, I'm guessing the motor isn't supressed, as it's sealed inside the plastic housing for the outboard and directly connected to the prop. The reason I know this is that I took the last one apart to check it and it now leaks!!!! I've ordered another one.. is there any way to supress it without connecting the
capacitor
directly to the motor body?
7 years ago by EricMB
Forum
Motor suppression
Hi Colin, glad we could help. Since you are using a 12V batt. make sure the
capacitor
s are rated for at least 25V. 40 or 50V to make sure.
ON NO ACCOUNT USE ELECTROLYTIC TYPES WHICH ARE POLARISED (+/-) ON A REVERSIBLE MOTOR! Otherwise they can go off like mini mortar throwers!
Quite spectacular, creates a mini snowstorm. Used to do this deliberately in my test engineer days to scare the knickers off the girls in production dept. ππ
Re 'Close at hand'; this is relative these days (apologies to Albert E!), you are in Hereford, I'm in Munich! But still only milliseconds away! π
Looking forward to pics of the relaunch. ππ
7 years ago by RNinMunich
Forum
Motor suppression
Hello Colin.. There was a very good description of motor suppression in the MMI plans handbook a couple of years ago..
Using Disc
capacitor
s, values were stated at 47 nf across the motor terminals, and 100 nf across each motor connection to the motor can, keeping the
capacitor
tails ( wire ) as short as possible at the motor terminal end. As for voltage rating, a general rule of thumb is to double the operating voltage at least, in this instance i would use 50 volt rated
capacitor
s.. Regards Muddy....
7 years ago by muddy
Forum
Motor suppression
Hi Colin,
The website has info about this
https://model-boats.com/rc/motors/suppression
capacitor
s should be easily available at Radio Spares etc; use only the flat ceramic types. Some model shops carry suppression pack with the 3
capacitor
s you need. Cheers Doug π
7 years ago by RNinMunich
Forum
Couplings
No apologies required. I need all the help I can get, as I'm completely out of my depth when it comes to the electrics and
capacitor
s and relays etc. I am taking in as much as I can but lots of it are way over my head. I have already had it running off of an ESC but with no reversing. Thanks TOM.
7 years ago by BOATSHED
Forum
Couplings
Hi again, WIMA FKS ='Folienkondensator' which means it is a polyester foil
capacitor
. Ceramic is more suitable. The 0,1 - 100 means it is 0.1microfarad, 100V DC.
π
7 years ago by RNinMunich
Forum
Couplings
Hi Tom, Re
capacitor
s - check here, Radio Spares.
http://uk.rs-online.com/web/c/passive-components/
capacitor
s/ceramic-multilayer-
capacitor
s/#esid=4294955811&applied-dimensions=4293330461,4294466459,4294817747
Any of these should do the trick. I filtered out anything not suitable for this purpose.
Cheers π
7 years ago by RNinMunich
Forum
Couplings
Hi Doug, the motor already has a
capacitor
on it, the markings on it are 0.1 - 100 WIMA FKS. I assume that that is sufficient. The box says only needs a single pole switch or relay for reversing. I will just need to sort out wiring up the relay.
7 years ago by BOATSHED
Forum
Couplings
Hi Tom
There is a Taycol site that may help you with your Taycol motors
http://taycol.tk/wiring.html
There are slight differences in the different motors and your Double Special falls into this category. The diagrams are clear and you should be able to modify OK.
There is a special page for the Taycols with reversing coils such as the Double Special. This uses the Bridge rectifier without any modification to the motor. For your 10 amp bridge rectifier this would be the best option as it will effectively double it to 20 amps. 25 amp are recommended.
The caps you have are not of the right value you need 0.1 uf (Mfd) or 100000 pF (Mmfd). You may also see them as 100nF. Ceramic are the type you need.
http://www.justradios.com/uFnFpF.html
The above is a useful chart of the different
capacitor
values most often quoted in electronic diagrams.
Doug has certainly shown the way and if it encourages others to ressurect and modify their Taycols all to the good.
Good luck with the modification
Dave
7 years ago by Dave M
Forum
Couplings
Hi Doug, Many thanks for your advice on the Taycol wiring.The ESC I am using is for reversing as well. I am not too good on the electrics and reading the electrical diagrams. But the centre diagram you have posted seems straight forward to me. I also have a Taycol Double Special that I will be using. Will your centre wiring diagram be the same for use with the Double Special. Also would it matter if a 10amp Bridge Rectifier was used and on a quick search all I can find is at Maplins is a Resin-Dipped Ceramic 100pF
capacitor
would this be sufficient.
Tom.
7 years ago by BOATSHED
Forum
Couplings
Hi Boatshed, I'm converting a Taycol Target but the principle is the same with Supermarine. Attached are the original Taycol diagrams for the Supermarine wiring, plus a wiring graphic, with circuit, of the mods for reversing it!
You will need a bridge rectifier, BR, (or 4 single power diodes, see attached diagram) rated for at least 5 or 6 Amps. Essentially the DC outputs of the rectifier (+ & -) got to the brushes. The two AC connections (~ x2) go the the field coil. (I'm not yet convinced that this is the best way round!) Also, put two 4Amp fuses in series with the field coil and one brush connection.
For suppression try a 0.1 microfarad non-polarised ceramic
capacitor
across the brush terminals. Otherwise the pyrotechnics at high revs are quite spectacular π
I assume that the ESC just controlled the speed without reversing?
Good luck, let us know how you get on. Cheers Doug π
PS I'm about to test my reversing board, wish me luck, more later. π
7 years ago by RNinMunich
Forum
Couplings
Boatshed
Use whatever you want as a coupling with the Taycol. its so inefficient it will make little difference. They are major sources of interference but
capacitor
s and careful screening will allow them to work with modern RC and ESC's. if you use metal to metal couplings they can cause interference.
Your brushless will require a good well engineered modern type coupling with the motor and shaft in alignment and solidly mounted.
I use a 42xx brushless in my Sea Queen and it is fast. Has your Crash Tender two props? if not the Super Marine should be OK. I would use a nice 3 cell LiPo to make up for the lump of lead that is the Taycol. A brushed 800 would be suitable for either model.
If you want reverse you need to modify and add a bridge rectifier. Doug (RNin Munich) is converting his Taycol so perhaps he will post a blog.
Good luck with the build
Dave
7 years ago by Dave M
Forum
2 motors 1 esc
Hi Sonar
I suggest you try maplins http://www.maplin.co.uk/. Look under components/
capacitor
s and you want the second page ceramic
capacitor
s 0.1uf.
If you have a local outlet it will be quicker.
You do not need a dual ESC two identical ESC's is the way to go.
If you are considering Mtronik look at http://www.mtroniks.net/cat/ex-demo
I have used several of their ESC's and they work well. The ex-demo refers to ESC's that have been tested to spec, so you do know that they will work.
Dave
7 years ago by Dave M
Forum
2 motors 1 esc
Another suggestion is to look on the Cornwall Model Boat Website for their recommended
capacitor
s.
7 years ago by figtree7nts
Forum
2 motors 1 esc
There are hundreds if not thousands of 0.1 uF
capacitor
s across the terminals on Ebay what would be the better to buy.
7 years ago by none
Forum
2 motors 1 esc
I have used this type of motor and they work well. if you are after torque then a five pole motor will give more. You are running at excess voltage so they will exhibit some stress if run at full power for any length of time. You should measure the current at 12v to see what is being drawn, I believe mine when connected and running free used to draw about 2.5 amps on 12v. it will be considerably more under load. I used three 0.1 uF
capacitor
s across the terminals and case as they will spark at the higher voltage. Do also make sure that all your (dirty) power wiring is well clear of any servo wires and the rx and aerial.
They can be quite current hungry and I used an Electronize ESC on each motor. Any good 20/25 amp ESC will be suitable but if you are using two and they have a built in ESC you need to remove the red (+ve) wire from one ESC lead to the Rx.
Good luck and please post details of your final choice and experience.
Dave
7 years ago by Dave M
Forum
Soldering suppressors to motor
Regarding brushless motors, you must not add any
capacitor
s across any of the three connectors.
The interference is caused by sparking between the commutator and brushes on a brushed motor, and brushless have neither.
I would tend to agree with AlanP regarding lack of interference from un-filtered brushed motors when using 2.4Ghz.
However if you are into fast electric then suppression is important as their motors can generate lots of RF noise and losing control of a fast craft is not to be recommended.
Whatever RC system is being used all signal wires must be routed well away from any motor high current wires.
It's good to see that we have members who have and share their knowledge and experiences.
Dave
7 years ago by Dave M
Forum
Soldering suppressors to motor
Hi Mikelin2
I must agree with Georgeo5664, follow his directions you can't go wrong. you must solder the
capacitor
s like he has described.
The
capacitor
s will help with any interference made by the motor(S)
Take your time and look at the picture.
You need to use
capacitor
s that are the right ratings.
lets say 2
capacitor
at 0.1uF and one at 0.047uF now slide the 0.047uF
capacitor
through both terminals on the motor, slide the ends of the 0.1uF
capacitor
s onto the opposite end of the motor terminal. now solder the terminals with solder.
Take the ends of both 0.1uF
capacitor
s and solder them to the case of the motor. Make sure you grind down a bit of the case. so that when you solder the
capacitor
s to the case they stick to the case.
Don't forget to solder on the leads, that go to your motor(S).
Now as to the question about do you need the
capacitor
s
I would use them know matter what, just in case.
But I've been told that if your using a radio that's on 2.4Ghz,
You don't need any
capacitor
s...
I hope this helps
But, in the event that you still don't get it, I would try to become a member to one of the local RC model clubs near you.
And see if someone can help you with your motor.
NOTE:
Please use this information for a Brushed motor Only!
7 years ago by figtree7nts
Forum
Soldering suppressors to motor
mike yes suppressors are required it helps to cut down the interference from the tx 1
capacitor
goes from + to casing 1
capacitor
goes from - to casing and last one goes from the + to the - pins on the motor hope this helps
7 years ago by georgeo5664