Model Boat Mayhem
Technical, Techniques, Hints, and Tips => BRUSHLESS Motors and Speed Controllers => Topic started by: Nordlys on April 25, 2019, 04:00:24 pm
-
Is it wise to use a ground ESc for my boat instead of the obvious Marine type?
They appear to be cheaper in some cases but will I not have good control
over the boat going from forward to reverse?
Nord.
-
Having raced various 1/10th cars over the years, a lot of car ESCs have a delay between forward and reverse, and some have limited power in reverse (designed for braking, rather than high-speed reversing). I think the only car ESC that I've used that had instant full-power reversing was a Novak brushless crawler.
If you can put up with a couple of seconds delay, go for it. Probably not an issue in normal running, but could be frustrating while trying to get alongside at the end of a session.
I think Hobby King have some "instant reverse" car ESCs
-
I use the cheapest possible ESCs for my models - the 320A ones from ebay for £5.
That said, I build slow-moving scale models so any delays will not be noticeable.
-
Each to his own but I don't build that many boats and so prefer to fit quality kit designed for the job and preferably sourced in the UK. But go with whatever works best for you.
Colin
-
Most car ESCs have what I like to call 'double dip' reverse functions to protect the cars gearboxes from dinlo's! You can slam the throttle stick hard into reverse and all you will get is a quite powerful braking function. Back to neutral and reverse again will enable reverse motor control.
Some car controls can be set with no reverse, instant reverse for crawlers, or 'double dip' for normal driving modes.
My views on 'cheap' are probably well known! I now know what these nasty little red pcb speed controls are. Four have crossed my field of view at work recently, three were consigned to the bin as unserviceable..still, at five quid each you can buy a few and take pot luck that some will work for the lifetime of the model! Me, I will stick to branded stuff, I like my models to work, all the time ok2
-
My thoughts exactly!
Colin
-
Nord....as a youngish builder {-) ......you will know......if you spend 20 Pounds on a vessel, then a 3 Pounds ESC is probably a fair risk
You could always see your 23 Pound vessel accelerate away at top speed [with a non responsive ESC] ...steering non functional due to electrical malfunction .....& still thrashing over the waves to the horizon & never to be seen again <*<
If one of these burns out in a car, you have a good chance of walking over to it......
Derek
-
Just to support what has already been said. You spend weeks, months or more and £xxx building your pride and joy. Do you then sit back and think, hmmm, I'll save a few quid and risk the lot on a suspect piece of gear.
I have to admit that I've had two of the cheapo speed controllers, I bought them out of curiosity to run a pump bow thruster, a non critical system. They were laggy, impossible to control to my satisfaction, and failed very quickly.
Naturally, you will hear about people who have bought them and been perfectly satisfied, but it's a lottery, and not many people win those.
Chas
-
Things electrical seems to be a blind spot for many modellers. Why this is so is unclear to me, even after years of being involved in the manufacture and sale of electronics for model boats. My story of one such customer bears repeating.
He denounced our speed controllers as expensive and complex (complex??) and proudly announced that he bought his ESCs from a Chinese on-line supplier for £4 each. When I queried what he did if one of these failed he told me that he purchased them in lots of ten. He then went on to say that, of the ten he buys, six never work at all; two will work but quickly fail; one will last almost a season and then pack up while the last one will continue to work. I asked him why he didn't save some money and buy a decent UK-made unit with a warranty and repair service. "Ah!" he said "but mine are only £4 each!".
What can you say?
DM
-
I've been using them for years on many, many boats and never had one single failure.
You could claim I'm lucky - but it's horses for courses. After seeing the rats-nest electrical installations in lots of boats, I'm not surprised about any failures.
If I was building a high-speed racer then I'd use something better - but for trundling around the pond they're perfectly acceptable. Same with my RC gear - I find the low-cost Hobbyking stuff to be perfectly acceptable. Again, if I was flying a complex stunt-plane I'd be buying something better.
-
Same here, I bought one a years ago to try it out and have never gone back. I use them in all my boats now and never had one fail yet. I use a few different types, from the 10amp micro jobs to the 320 amp buggy type, I just pick ones without the brake feature.
Each to their own I suppose.
-
In reply to your posts (thanks), I'm not so concerned about the cost, more so about the braking aspect that ground ESC's have compared to Marine types
ie I cant go straight into reverse and how do you program these ground types for marine use?
N
-
I think a better term to use is car or buggy ESC. They're not really ever called "ground". If you use car or buggy, there's a ton of info out there about them. If you look on here somewhere recently we talked about a hobby king ESC (dual output). It has dip switches for car or boat mode (and lipo or ni-mh). There's not really "programming", that's more for brushless. Personally I would never buy a cheap Chinese one. I tend to stick to mtronics these days. Some have a set-up button but the newer ones are self centring plug and play for about 2 quid more I think.
-
If cost isn't an issue, why mess about? Just buy an Action esc or mtronics Viper.
Other premium brands are available, those are the ones that I've bought many times over the years and have been excellent.
Chas
-
Component shop refer to them as Ground?
N
-
If cost isn't an issue, why mess about? Just buy an Action esc or mtronics Viper.
Other premium brands are available, those are the ones that I've bought many times over the years and have been excellent.
I don't consider Vipers exactly a "Premium" product, for the price they seem to go in, work and keep working. Pretty much all I want. You can get them wet too and they keep working - I've still got a couple in use from boats that have sunk.
The story about the bloke who buys lots of £4 units reminds me of reading about cheap starter motors for VW buses. Each came with a lifetime guarantee but you had to take it back to the shop. Several people pointed out that unless you liked regular trips under the vehicle with a spanner, buying a good one in the first place was a better idea.
-
I didnt make it clear in my original post that the ESc (x2) Im looking for is for Brushless motors! Oops!
I do agree with you that Viper Mtroniks are very suitable and easy to setup - most, if not all of my models have them.
Im not that familiar with Brushless set ups and car/buggy ESc's seem to be less expensive than marine ones but require setting up - am I correct?
N
-
Most car ESCs have what I like to call 'double dip' reverse functions to protect the cars gearboxes from dinlo's! You can slam the throttle stick hard into reverse and all you will get is a quite powerful braking function. Back to neutral and reverse again will enable reverse motor control.
Some car controls can be set with no reverse, instant reverse for crawlers, or 'double dip' for normal driving modes.
My views on 'cheap' are probably well known! I now know what these nasty little red pcb speed controls are. Four have crossed my field of view at work recently, three were consigned to the bin as unserviceable..still, at five quid each you can buy a few and take pot luck that some will work for the lifetime of the model! Me, I will stick to branded stuff, I like my models to work, all the time ok2
having used all major named brands, I found that the only 2 that are reliable were action and electronise ! i also use the cheap red £5 ones in my smaller models and have had no problems, not had one blow in 2 years of using them. mtronics I have had blow on several occasions and returned them to get another by return if post, but i dont trust them, and yes i do put an on line fuse. all my bigger hull boats use electronise and action gear, not cheap but very reliable. have used hk x45, 1 runs out and it released magic smoke. have used tornado 50 amps another one that blew, aquafusion esc that was a good one and sits unconnected in my robbe atlantis! used the £10 320amp ones off fleabay and had my first one blow last week in a ASRL with a Johnson 600 motor and 7.4v lipo. we think the servo had a fault and fed back somehow....not sure really. but tgat released magic smoke as well!
-
I have a Hobby King 30A brushless car ESC in a boat.
https://hobbyking.com/en_us/hobbykingr-tm-brushless-car-esc-30a-w-reverse.html
It works OK so far but I'm only running at less than 10A. There is also a programming card available separately for simplifying any programming required.
I bought it because I wanted an ESC that didn't need water cooling. Most of the programming relates to braking but it can be left at the default settings. I can't see that anybody would care about the braking in a boat. So the prop is braked - so what? It makes very little difference to my boat as far as I can tell. Why would you want to slam it straight into reverse anyway? I haven't noticed any delay but then I only switch to reverse from slow ahead.
However I have found one problem to be wary of and that is the Low Voltage Cutout. I set the LVC at a suitable value but the Lipo I was using had run down a bit. I was running at slow speed and then pushed the throttle stick forward. The resultant slight drop in battery voltage caused the LVC to shut off the ESC. The BEC was still providing power to the receiver but no amount of stick waggling would bring it back to life. It didn't matter at the time 'cos I was testing in the bath and obviously it wouldn't be critical in a car but in a lake?....
Subsequent testing showed that the ESC will recover if the throttle is at 'stop' and the battery voltage recovers by about 1volt. The trouble is if the battery is low and you're not taking much current, the battery voltage probably won't recover by that much and you're stuck.
Anyway I've programmed the LVC at 0volts and am trying to find an adjustable and LOUD LV audible alarm.
My 2p supplied.
NNF
-
Hi Nordlys,
Going back to your original question, and having found out this is about brushless motors. Is it not worth posting a bit about the model and motor you have -I can's ee any mention so far and might help taylor some advice. Depending on what you're doing it may make little difference.
Car / buggy or now we know "ground" ESC's will undoubtedly be cheaper per-se. There's orders of magnitude more RC cars and trucks than boats, so no surprise there's probably a bit of a price difference. Mtronics, ACTION or Electronize (brushless or not) certainly are not in the "premium" category. As to how much you want to spend, personally I would always buy from my local shop first, or mail -order from a reputable supplier rather than the cheap imports. As for programming -it's why I've stayed traditional so far because I'm not interested in the extra faff for the limited benefit for my applications. But if you can explain your application someone will be able to recooemd something suitable (just don't expect one single BEST answer LoL).
Rich
-
Hello Rich.
Yes, I have left out some details of my requirement in this post, so let me add them in now!
I am building a 41 inch Seaplane tender with twin motors from scratch. I have been considering fitting slightly larger brushless motors to this model than my earlier 37 inch Seaplane Tender ST206, however, Howes models, who I used last time for the smaller model didnt have a larger version of the package that I bought then, Mtroniks 1100Kv with a 15amp Mtroniks ESc. So I have settled for the same size motor with the 30Amp Esc package ( you can view them on their website).
I could have gone for a car/buggy Esc with good size motor but it meant I would need to faff about with settings - and the model shop warned me that the motor would not go straight into reverse to slow the boat quickly but that I would need to tweek the control further to enable this.
Anyway, I hope that my choice of motor now will power her along with enough zip. Thats all!
Nord.
-
Not that I know much about the subject, but might I enquire why this has been moved to "Brushed DC Motors and Speed Controllers"?
DaveM
-
Moved and renamed. :-)
-
Brushless motors, so far, mostly end up in performance boats. While the "brake" function is pretty much useless in a boat, occasionally, when sailing, you need brakes, if only to avoid damaging the fast approaching concrete bank. Reverse is your brakes, and when you want brakes, you want them in a hurry. Double dabbing, making life more complicated at a crucial time, doesn't help.
-
Thanks Malcolm, that pretty much makes me stay with Marine ESc's. I like your Double dabbing description and I do agree its not a good time to be faffing about heading for the bank full chat!
N
-
https://www.youtube.com/watch?v=kk7P8f8qYVw (https://www.youtube.com/watch?v=kk7P8f8qYVw)
hi there these are brushed motors in this model - but - I was trying out a new (from ebay) a Chinese speed controller with programmable brake function. The reason I liked this is that it only had 50% power in reverse - because on this model where the rudder posts come up at the stern/ there are slots at the top to take the rudder tiller arms. Water can enter through them if you do full reverse :-) but, it turns out that the reverse and brake function are so hitty missy on this particular speed controller, it is being replaced. Watch the video and have a laugh :-)
This is the speed controller
https://www.ebay.co.uk/itm/60A-Dual-Mode-ESC-Motor-Speed-Controller-with-Cooling-Fan-for-RC-1-10-Car-UK/273447546158?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2060353.m1438.l2649
John
-
I have a 120a Hobbywing ESC in my Chris Craft Runabout and the programming card give the choice between a pause in neutral and instant forward/reverse. This has always worked perfectly, I bought a second hand Robbe Turo, the ESC fitted looked like a Hobbyking 40a so I bought the requisite card and found that it also offered neutral or instant, and that works fine as well (and is a much cheaper unit than the 120a ESC)