How a mouse caused Me to reflect on DEF 32A varnish :-
Its that time of year again, SWMBO got me to get the christmas decorations down from the loft. It seems that a mouse (or squirrel?) had chewed some gold sprayed polystyrene "seeds" on a piece of decorations. SWMBO said could I block up the holes in the storage crates?. I then remembered that in the workshop, I had some storage crates which had sealed lids, so I thought by using these I could earn some brownie points.
To gain access to these crates I had to roll away a really heavy storage rack, which had at least 100 Kg of tools on it, so I slowly moved the rack and gained access to my crates. The contents were then decamped into SWMBO's crates and my contents were put into the more open crates and stuck back under the bench. This is when disaster one occurred. Rolling the rack back it shed a wheel
. Trip to a supplier, £21 worth of castors rated at 100 KG each and 4 hours work.
I had noticed that a shop made tool grinder which was also stored under this bench, had a mutilated 13A plug on it. Oh well, I might as well sort this out so the machine could be used. Changed the plug, When I switched it on, it operated for about 5 seconds then all the lights went out. B****r, unplugged it, reset the earth leakage trip in the house. Got the Insulation tester out and sure enough the insulation of the motor was only 5 M ohms at 600V. Stripped the motor down and the PVC insulation on the lead out wires within the motor had cracked and some had fallen off but the basic windings had an infinite insulation resistance. OK, so I sleeved the wires and reassembled the whole motor. Tried the insulation out again. B****r, its failed again, took it all apart and the point of failure was the paxolin terminal board. It was a little grubby but looked OK . I put the board on the central heating boiler overnight and lo and behold in the morning it's insulation was fine.
I then reflected on , that when I was an apprentice one job we had to do was to do was to varnish the EDGES of cut paxolin insulation board with DEF 32A varnish. I see they were right!!!
No DEF 32A varnish , I am trying polyurathane varnish, but I suspect the fact the board has been dried out would keep it going for another 20 years anyway!
Merry Christmas to one and all.
Frank
Edited By frank brown on 20/12/2014 10:57:37