NASA Clipper log not working after layup...

Iain C

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I relaunched at the weekend, obviously with a totally clear log paddlewheel which should be sending info to my NASA Clipper Duet. But the display was not getting any speed info (echo sounder was fine).

I did notice that I could see rusty bits on the centre of the paddlewheel, as if something had broken off and had exposed some steel, although it span freely. Do I just need a new paddlewheel from NASA or is it likely to be a whole new transducer? It was fine before she came out for the winter!

Thanks
 
If you were seeing bits of rust maybe the embedded magnet has rusted away or dropped out in which case the paddle wheeel will spin but initiate no pulses. You need to pull the unit out and inspect the paddle wheel to see if the embedded magnets are still there. If not, you can get a replacement paddle wheel and fit it by driving out the pin and replacing the u/s one.
Morgan
 
That's not a bad price for that kit. I have now replaced my paddles and spindle three times. They last about three years. Sometimes it is the magnet that falls out but mostly it is wear on the wheel and spindle that stops it working properly. When I took mine out to antifoul it this spring, I noted that the dreaded rust was on the ends of the magnets. I only put that one in last year too!
 
Although I only replaced my paddlewheel last year, I am always on the lookout for 'spares'. A couple of weeks ago I was able to bid for and win a complete used transducer unit and paddlewheel, for about £15!

Down on the boat I plugged the 'ducer into the display and blew on the paddlewheel. Yep, it spun freely and worked ok. So I now have a good secondhand 'ducer and a free paddlewheel.

FWIT I always remove the transducer unit when not in use, and I store it vertically in a piece of 45-50 mm dia pvc tube screwed to the inside of the cupboard where it is used. This means that it dries quickly and remains dry. Also I do put a light coating of something like silicone on the paddlewheel magnet ends, just to try to eliminate water ingress. So far it seems to work.

Geoff
 
Had a similar problem with mine last year, changed paddle wheel, no difference, got a new sender complete and worked briefly, checked old one under tap and worked ok. fiddled around at the back of display and presto, seems the contact on the connection was a little faulty, have now sprayed with contact cleaner and hoping all will be fine on re-launch at end of month :)
 
Don't get too excited, by the time you've paid VAT and carriage there's really not much in it...

But thanks for the tips guys...new one ordered!
 
I replaced a broken paddlewheel (lifting straps, I think), and also acquired a complete new unit (both obtained from NASA). I now have two good units...I have cut the co-ax cable, and fitted a 4-pin mini-DIN socket in a dry area to the "boat" end, and corresponding plugs to each unit (shield to two pins, and inner conductor to the other two). The plan is that if (or rather, when) the log gets overgrown with mussels during the season, I'll do a quick swap for the clean unit, and spruce up the one I have taken out. Trouble is that, although I know it's possible to do this without sinking when the boat is in the water, I haven't yet had the nerve to try it for real.....:eek:
 
I'll do a quick swap for the clean unit, and spruce up the one I have taken out. Trouble is that, although I know it's possible to do this without sinking when the boat is in the water, I haven't yet had the nerve to try it for real.....:eek:

I take mine out each time after use. It's a bit daunting, removing the transducer and leaving a 2 inch hole through the hull:D:D:D

I just ensure I have the cap right by my knee, and place my palm over the opening, and then screw the cap on. Should be just as simple to replace the transducer too. Only difficulty is that by kneeling down I tend to get ky knees a bit wet from the plume of water!:D:D
 
Only difficulty is that by kneeling down I tend to get ky knees a bit wet from the plume of water!:D:D

Hold the blanking plug in one hand and then cover the area, including your hand, with a towel/old cloth. The transducer can be held through the towel and pulled up and be replaced by the plug.

Still water in the bilge but no fountain.
 
Thanks for the advice....I'll try to prepare properly when I do the change over. It's probably wise to have someone else on the boat when I do it, just in case....:eek:
 
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