RMC bow thruster control panel replacement YAPP saves £1172

[AngusMcDoon]

I have a RMC swing bow thruster on my boat. This is one that pivots down from within the hull when deployed and then retracts leaving a smooth hull line. It is made by RMC, a Swedish company, although it was marketed by Lewmar and has Lewmar labels on it. There is a typical thruster control panel in the cockpit with a membrane pad with buttons for on/off, port, starboard, and a LED and a buzzer. The control panel is made of weedy plastic and after 15 years has degraded to the point of falling to bits.



Lewmar don't market RMC thrusters any more and don't want to know other than sell a new one. RMC are hard to find, but I found them eventually. Unfortunately they don't sell that panel any more and the panel they suggest is not compatible with the control box I have, so their suggestion is replace both along with all the wiring in-between the two. The cost is £1200.

Being a Scottish tightwad I'm not over enamoured in paying that much for a switch panel, so I got my screwdriver out and took apart the existing control panel and did some reverse engineering. The existing panel has no intelligence in it. It's just 3 switches, the LED and buzzer and a few discrete components. It didn't take long to figure that out. I quickly knocked up a replacement PCB in DesignSpark...



and a couple of weeks later I had 10 boards for £8.50...



It took no time to build the board...



The connector on the end to the wire that goes to the control box I did a reverse image search and found it straight away - it's a standard automotive one and cost only a few groats...



For the panel I ordered some waterproof push buttons and appropriate o rings. I bought some anodised aluminium plate in 5052 which is a corrosion resistant alloy suitable for marine use. A door kick plate supplier sold me an offcut for not much. The LED is held in with epoxy.



For the seal at the back I got some closed cell foam sheet and stuck it on with double sided sticky sheet from 3M



Here's the complete thing...



The buzzer just dangles, as did the original one. Here it is in situ...



£1172 saved. I wonder why RMC couldn't do that and flog them for £300.

 

[AngusMcDoon]

I wonder why the forum thread list says that I posted this tomorrow. That's a bit relativistic.

 

[Minerva]

Nice work!

 

[nevis768]

Good job, thanks for posting, shows what can be done with a bit of effort and thinking out the (control) box

 

[oldgit]

.........and the same subject. VETUS.
On many vessels the bowthruster uses a toggle switch with little rubber sleeve to keep water out , this rots and allows water with the expected results.
Genuine original replacement two arms and two legs .
Various toggle switches which will do the job on Ebay for no money and simple to modify.
Did one several years ago and still working fine. £17.50.

 

[footsoldier]

Angus McDoon, that is in the true spirit of PBO. Excellent work

 

[rogerthebodger]

Well done Angus I had the same issue some time ago when my bow thruster switch failed I using a toggle 3 position spring centre switch with a centre off that worked very well

 

[Bouba]

Very impressive Angus

 

[mrming]

That looks a lot more robust than the original - nice work!

 

[dgadee]

What about a Yanmar engine panel? Replacement fory 6 year old one which went dud was £1,000.

 

[DownWest]

Very nice! Impressed.

Same prob on a client's boat. Vetus, as said, arm and leg (plus long delivery), so found some micro switches that were exactly the same and rebuilt it for near nothing.

Last year, friend with big old house was having trouble with his oil heating, as a rain dribble had got at the two electronic pcbs, arcing and carbonizing them. Spares were difficult and very expensive. So, scratched head.. He didn't use the programming section, so it was really a simple temp control with the overtemp safety and some timing. Made a panel out of polycarbonate sheet for 0 expense and works fine. (But did sort the dribble from the outhouse roof!)

 

[PabloPicasso]

Write up the article about this with all the details and with pics. Then submit to PBO. They are always looking for contributers, and pay some beer tokens too.

 

[AngusMcDoon]

Write up the article about this with all the details and with pics. Then submit to PBO. They are always looking for contributers, and pay some beer tokens too.

They have not been interested in my YAPP electronics projects before because designing and getting PCB's manufactured is not deemed within the capabilities of the average PBO person. Also RMC swing thrusters are rare.

 

[Plum]

Same prob on a client's boat. Vetus, as said, arm and leg (plus long delivery), so found some micro switches that were exactly the same and rebuilt it for near nothing.

Yes I did the same on my Vetus bowthruster joy-stick, just two cheep microswitches bought online that just clip into place

 

[Minerva]

Oh. So in the eyes of PBO, we’re all too thick?

 

[AngusMcDoon]

Oh. So in the eyes of PBO, we’re all too thick?

PCB design and layout is not a common area of knowledge outside electronics engineering and the diehard end of the maker community.

 

[PabloPicasso]

Well Angus, I found that very informative

 

[S04]

Not relevant so deleted.

 

[dgadee]

I looked parts but the odometer thing cannot be bought. B20:

 

[justanothersailboat]

PCB design and layout is not a common area of knowledge outside electronics engineering and the diehard end of the maker community.

Judging by the maker community I think it's become somewhat more accessible than it was, say, thirty years ago... times change, relative difficulties of things change. They just haven't kept up.

You did a fantastic job there.