AngusMcDoon
Well-Known Member
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.
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.
