Model Boat Mayhem
Technical, Techniques, Hints, and Tips => The "Black Arts!" ( Electrics & Electronics ) => Topic started by: Tug-Kenny RIP on December 12, 2006, 09:05:39 pm
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Hi all
Thought I would start a topic that something we did, .....WHICH was not such a good idea.
I'll start the ball rolling with the following mistake ..........
I'm wiring up my Tug electronics using the theory gained from 45 years as an electrician. Earth everything back to one point. Keep wires tidy and out of the way. Make access easy for repairs.
Presented with two motors and a bow thruster with their matching speed controllers, I started assembly.
I ran earth wires from the prop shafts to the motor housings and to one terminal of the motor armature. I then wired the Speed controller neutrals to earth through some ten amp fuses. (with me so far !!)
When the fuses blew for the 5th time, it occurred to me that something was not right !!
I have now rewired the speed controller neutrals to the motors and removed my lovely earth wires, except to the prop shafts. It now works as it should, and I have been suitably chastised.
Has anyone else got a useful tip or two to help us amateur's along the tricky road to boat building :)
Cheers...Ken
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Hi Ken,
Typical electrician - uses 5 fuses before thinking there may be something wrong. ;D
Also - you do realise that your boat will no longer pass a 16th edition test now youve taken all that "bonding" out.
Seriously, I have in the past earthed the motor casings to the propshafts in no problems, in fact it probably reduced interference within the model.
Terry.
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Hi Ken,
If I understand what you did first time around correctly, you wired the low output of the motor controller back to earth. This would blow the fuse as the motor controller uses a bridge configuration. The connections to the armature have to be floating with respect to earth because of the reversing operation.
I used dedicated wires for the motors to the ESC then starred up the supply lines at the battery so there are no shared current circulation paths.
I have physically separated the Rx and ESCs and motors to minimise the interference and routed the aerial as far as I can from the wiring
Tim
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Re Faradayscage post,
glad to see there is some humour creeping back in.
Andy
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Threw my Multi (race) boat in and knocked the radio switch off as it left my hands..... 50mph straight across the lake and flew up the bank and came to a stop, engine still screaming, near some very startled golfers! ;D
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Threw my Multi (race) boat in and knocked the radio switch off as it left my hands..... 50mph straight across the lake and flew up the bank and came to a stop, engine still screaming, near some very startled golfers!
Didn't make a hole in one then? ;D
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Spot on, Wombat.
The fuse did not blow until the joystick was pushed up on one motor and the second fuse blew when down was pushed on the other motor.
Never having seen ESC's in action, all this was new to me, so it was causing a lot of thought and theory reading until I realised the way it works.
Here is another BOO-BOO. I mixed up my epoxy using the filler twice (thinking I had picked up the hardener !!!)
It took ages for it NOT to go off. Silly me
Cheers...Ken
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A man after my own heart ;)
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Things that seem like a good idea at the time for me......
Hmm, I need a hobby, how about models boats....
Lets blog the build.....
If I thin the paint a little, it will spray better
After seven months on Aziz I have come to the conclusion that a model boat builder is someone with a thing for pain but is too embarrased to buy the whips and hand-cuffs from Ann Summers ;D
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I heard of a case where a modeller complained to a kit manufacturer that the model wouldnt float.
Appartently the instructions stated that the propshafts should be cemented into the hull.
I'll leave you to guess what the modeller had done :o
The manufacturer has now changed his instructions accordingly. ;D
Terry.
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Starting my latest project... 5 months in and not a lot to show for it.
Allowing myself to be nominated for chairman of our club.
Telling the wife how 'little' my latest toys cost.
Scottie
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Seemed like a good idea...at the time...... starting a Clyde Puffer build..... :-[
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Don't say that - mine has just arrived!
Father Christmas had better have chosen well >:(
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Seemed like a good idea...at the time...... starting a Clyde Puffer build..... :-[
AHhh most of us had forgotten the Clyde Puffer !! ;)
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Hi Wombat,
Which kit?
The Mountfleet Highlander Puffer is a great kit... my build will mainly consist of "don't make a meal of of everything. Keep it simple! This is how not to do it etc. etc!"
Martin
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Seemed like a good idea...at the time - I'll just pick my nose while the superglue sets. :-\
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Hiya Martin,
Yes it is the Mountfleet Highlander - will have ot see how it goes, certainly a very different style of kit to the Aziz - its got wood in it. The hull is going to take some work - there seem to be a lot of blobs and things on the plating. Still a challenge to be risen up to. Also a small split in the hull to be fixed (Boo) Got plenty of sanding-seal, just need to find some grain filler for all the dead tree.
The ladies of the house were amused by the contrast with Aziz - on Aziz the deck was a beutifully CNC machined bit of stryene - Mountfleet: a bit of plywood written on in biro ;D - no less accurate I'm sure but quite a cultural difference
Also just bought the prop on behalf of STD so her purse is going to be a fair bit lighter
Tim the Wombat
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.... I'll just pick my nose while the superglue sets. :-\
Hey! That's my job!
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Seemed like a good idea at the time.....
I'll just chop these chillies up for tea, then I'll go for a leak afterwards :o :o
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Seemed like a good idea at the time.....
I'll just chop these chillies up for tea, then I'll go for a leak afterwards :o :o
You can laugh, but I've done that too, and picked my nose as well, that really is me in my avatar you know. It's what's called 'burning (the candle) at both ends'.
And, before anyone comments, I'm left-handed, so it's not the same finger....