Upgrade capacitor start on Poolewood 2840?

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I have a Poolewood 2840 with a YB 1hp (6pole, 9amp) motor. Most of the time it starts and runs and fine, but occasionally there is a big flash, loud bang, and the ring main trips - gives me a fright each time and makes pressing the start button a bit of a tense activity....

I've checked the centrifugal switch and it moves well, but the contacts on the fixed contactor plate are pitted and there is black marks in that area and it is where the flashing is happening when the motor gets up to speed and the centrifugal switch breaks the starting capacitor windings circuit.

I assume the problem is the pitted contacts (not quite sure what is arcing though when they move apart) and i have a cheapo replacement on its way from china (only one i could find listed (19mm bore).

My question is should i take the opportunity to replace with a solid state relay/contactor (i like the idea), and if so any recommendations for a product with a uk supplier?
 
update on my own post:

cheapo centrifugal baseplate arrived and worked, but still flashes as disengages which i thought would lead to the contacts pitting and the fault reappearing.

I therefore purchased a solid state start switch for £36, ebay (https://www.ebay.co.uk/itm/Electronic-M ... 2749.l2649)

A little rewiring was required (joining contacts from removed centrifugal switch plate at motor end, supplying the negative feed for the start cap circuit from the new switch in the wiring box and supplying the switch with a live and negative feed).

Two notes - the new switch puts out a negative output for a short duration - in wasn't clear from the diagrams what the output was, but on testing it is a negative output.
Second point of warning - turn the time adjust screw many times to the left to decrease the start duration to the minimum (1/4sec i think). I tested on the bench with a LED to see duration, but only after i fried the original the cap because the switch was on about 3 secs duration! Once i had it on minimum I then increased it gradually once fitted until the motor started smoothly. The new 300MFD cap was £7 off ebay, but i struggled to find one small enough to fit in original enclosure so now mounted below it.

the lathe now starts smoothly and with no sparking, banging, tripping, and i'm feeling less apprehensive each time i press the start button...
 
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