Is this why my speed log doesn't work?

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The boat we just bought is ashore and the speed log doesn't work. It had no plug on the coax, so I (think) I've sorted that, but could the damage shown in the pic be the culprit? It's a NASA Clipper.IMG_20240918_174042-EDIT.jpg
 

Refueler

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If that blade is the one that should have the magnet stuck in it - without the magnet - its useless.

You can repair that with gluing a rare earth magnet in that chipped area and surrounding with epoxy ... making sure of course that it can still spin freely ..

Coax plug is easy fix.
 

pandos

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What sort of an attitude is that?

I think you must have confused this for the YM Scuttlebutt forum. This is the Practical Boat Owner forum, don't you know? ;)
If you try hard enough you should be able to find a repair that will take twice as long and ought to cost at least 10 pounds in fuel and time..
 
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What sort of an attitude is that?

I think you must have confused this for the YM Scuttlebutt forum. This is the Practical Boat Owner forum, don't you know? ;)

Tee hee! I think any repair I did for something that's going to be spinning in water would last about 5 minutes!

But don't worry, I will be attempting a fibreglass repair of the bottom of the companionway at the weekend if it restores my credibility to use this forum.:p:unsure:
 

Refueler

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I must admit that some posts on some threads make me wonder if person is suited to boating and / or PRACTICAL boat owning.

I've noticed in the 6 decades I've been boating - the change from creating / repairing / innovation ..... to .... Credit Card boating ... but I have to say that today at 68yrs old ... having snapped spine and had it welded together ... my days of crawling about boats are limited .. so I do tend to Credit Card solutions now.
 
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I must admit that some posts on some threads make me wonder if person is suited to boating and / or PRACTICAL boat owning.

I've noticed in the 6 decades I've been boating - the change from creating / repairing / innovation ..... to .... Credit Card boating ... but I have to say that today at 68yrs old ... having snapped spine and had it welded together ... my days of crawling about boats are limited .. so I do tend to Credit Card solutions now.

Each to their own I guess. I'm doing up an old boat with my 16 year old son who is an engineer in the making and just loves it. We also love doing a joint project (he actually paid 30% of the boat out of money he'd made doing up smaller boats). By the time she does back in the water next March I expect we'll have spend hundred of hours on her, both learning new skills. As I said, we're going to be doing some fibreglassing at the weekend, something I've never done. I am an IT lecturer, not a boat builder, but love to learn new skills and spend time with my boy.

Other people have loads of money but little time so are quite happy to pay others - and that creates jobs, so all good.

But for the sake of a 5 minute drive and 8 quid on a paddlewheel, I'm not going to waste time trying to glue back bits of plastic that I know will only break again.
 

rogerthebodger

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IMHO sailing does not need a Practical boat owner but if you are out at sea and something goes wrong, and you are the only one available you need to fix the issue before it becomes dangerous.

That is why I did most of the work on my boat, so I know where all things are and have the ability to fix it at least have a get you home solution
 

KevinV

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There always are /will be plenty of jobs where repairing/making from scratch is the practical thing to do, either from a cost or availability point of view.

Other times - ie when you have lots of other jobs to soak up your most valuable resource, time - buying and fitting an inexpensive, easily available part is the practical thing to do.

Bravo RFT, I have very fond memories of this sort of quality time spent with my father at that age - we tended to argue if we weren't busy.
 

KevinV

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And after all that - it still doesn't work! Now checking the cable...
From memory you can test the log and cable with an ohm meter - as the magnet passes the sensor the resistance should drop from infinite to very little (or the other way round, I can't remember)
 
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From memory you can test the log and cable with an ohm meter - as the magnet passes the sensor the resistance should drop from infinite to very little (or the other way round, I can't remember)

Ah ok - I did see a guy on Youtube do this - but I'm not sure what settings to put my multi meter on. I'll have to ask Mr Google!
 

Refueler

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A three wire sensor I agree .. but principle is same on the coax version ... the magnet acts on the sensor in the main body and a spike voltage occurs .. as far as I recall - it is NOT an OHMS matter - but a voltage matter ... therefore to test its basically set Multi-Meter to low volts range (0 to 6V) and then connect outer shield to -ve .. centre lead to +ve .. turnm paddlewheel ...
 

rogerthebodger

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If the speed sender has 3 wires its a hall effect sender so yes you are looking for a voltage pulse not continuity as you would get with a reed relay type sender which would be a 2 wire sender
 
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