lotus_esprit_s1
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Little Christmas project completed - I rescued this little Lincoln Invertec V140s a couple of weeks ago out of a semi derelict workshop / barn. I plugged it in and it seemed to work however on inspection the positive terminal on the front had melted, and there was a rattle coming from inside the machine.
After opening it up I found that two ceramic resistors on the pcb had appeared to have got too hot at some point in the past and shed their ceramic cases, causing the rattle. Looking on line, it appears to have happened to at least one other machine, although they did still read the correct resistance. I stripped the PCB out and found the correct schematics online. With advice from Eddie49 I ordered a pair of replacement resistors (£3.29 each). Luckily being an early inverter it had through hole components not surface mounted so it was a straightforward repair.
While waiting for the resistors to arrive I took a look at the melted socket. The positive Dinse connector was jammed in the machine due to melted plastic however managed to remove it and found that the last user had only turned the connector a couple of degrees. That causing high resistance coupled with the appalling state of the leads I presume caused the socket surround to melt.
I removed the female Dinse connector from the panel by heating it up with a soldering iron so the plastic would melt, and then pushed it out. I then set the front panel up on my mill and with the correct size endmill machined away the molten plastic back to the original depth, and reinstalled the socket.
The resistors arrived this afternoon so I installed them, cleaned and reassembled the machine and gave it a test. Welds really nicely and nice compact machine. I’m really pleased how it turned out, especially the melted socket repair. Next up might be a Murex Transtig 200acdc currently sat in the same barn!
After opening it up I found that two ceramic resistors on the pcb had appeared to have got too hot at some point in the past and shed their ceramic cases, causing the rattle. Looking on line, it appears to have happened to at least one other machine, although they did still read the correct resistance. I stripped the PCB out and found the correct schematics online. With advice from Eddie49 I ordered a pair of replacement resistors (£3.29 each). Luckily being an early inverter it had through hole components not surface mounted so it was a straightforward repair.
While waiting for the resistors to arrive I took a look at the melted socket. The positive Dinse connector was jammed in the machine due to melted plastic however managed to remove it and found that the last user had only turned the connector a couple of degrees. That causing high resistance coupled with the appalling state of the leads I presume caused the socket surround to melt.
I removed the female Dinse connector from the panel by heating it up with a soldering iron so the plastic would melt, and then pushed it out. I then set the front panel up on my mill and with the correct size endmill machined away the molten plastic back to the original depth, and reinstalled the socket.
The resistors arrived this afternoon so I installed them, cleaned and reassembled the machine and gave it a test. Welds really nicely and nice compact machine. I’m really pleased how it turned out, especially the melted socket repair. Next up might be a Murex Transtig 200acdc currently sat in the same barn!