• A missing screw

    Alan Liefting

    A Philips 42TA2800 LCD TV came in for recycling.
    “It works” the customer said, “It is just the power switch.”
    The actual plastic power switch actuator was missing and you could see that the power switch circuit board was just dangling off the cables.  It looks like they were poking the pcb mounted power switch (two in series) to get it to turn on.  I don’t think they had the remote control for it.

    After taking it apart I discovered this:

    Photo of the rear of the power switch circuit board
    The power switch circuit board is positioned to try and show the lack of a second screw ever having been present in the plastic support.

    There was ever only one screw holding the power switch circuit board in place.  The other was never fitted!  So the plastic support broke.  Not surprisingly. This is a power switch.  Something that is often abused.  And in this case it had to do a lot of work because of the lack of a remote.

    So what happened here Philips?  Are these TVs not made in highly automated factories with all sorts of quality checking including the use of image recognition?  So did this one slip past the inspections?   Or is this inbuilt obsolescence?  Or are you saving one screw and one extra assembly operation to save a fraction of a cent?

    Get back to me on it please Philips.  Thanks.

    Anyway, talking about customers and switches and faults brought back some memories. When the customer said “It is just the switch” I was reminded of my days repairing the old school CRT monitors and the even earlier days of repairing CRT TVs.  Customers would sometimes give their diagnosis as “It is just the switch” or “One of the guns has gone”.  It got the stage where I thought customers think that a CRT TV or monitor only consists of a CRT and a switch!  They don’t know that there are power supplies, HV stages, signal processing circuits all containing resistors, capacitors, semiconductors, wires, cables, connections etc and all of which can fail.

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  • A lot of packaging for a small screw

    Alan Liefting

    I was sorting a consignment of recycling in one of our e-crates when I came across this:

    Can you see the screw?
    Can you see the screw?

    So here we have an M2x3 mm screw with part number DP/N OHCN8P or SG-OHCN8P-M0287-27C-1TRF REV A00. And it is quite a lot of packaging and quite a lot of part number for such a small item! Welcome to the 21st century I guess.

    I think the screw is for a bit of Dell computer gear. Now Dell is normally quite good with their environmental policies but in this case it is not so good. This screw is probably used for mounting accessories. I would have thought a better way of supplying a screw for this sort of thing would be to incorporate it directly into the product. This idea is nothing new. In the old school XT’s and other desktop computers the screws used to hold in the expansion cards were part of the case (and held the blanking plates in place). Later models of desktop cases just had integral blanking plates that had to be broken out before putting in an expansion card. And there were no screws supplied!

    Anyway, back to this M2x3 mm screw. Surely there would be a spot somewhere in or on the gear that it is used on where it could be stored? From an environmental point of view two plastic bags and a piece of paper would not be needed. From a job costing point of view there would be less material and less individual operations saving money on the production cost of the piece of gear.

    Speaking of small screws I came across a website called LaptopScrews.com, a US based supplier that supplies, well, laptop screws. This is great! A supplier of a very specific product that is sometimes needed by repairers and DIYers.

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  • I’ve done a lot of screwing

    Alan Liefting

    I’ll probably get in trouble with everyone about the title of this post but at least it got your attention.

    Anyway, as a technician I do a lot of screwing (we are only talking about screwdrivers here ok) so having good screwdrivers is a good thing.  Have a look at this CK HD Classic range screwdriver that I bought way back in the mid 1990s.

    IMG_2433 CK Screwdriver
    It is a Number 2 Philips head screwdriver so it has done a lot of work.  Look at the tip.  Apart from the anti-cam out coating being worn off it is still in good condition.  The rough patches on the shaft is where I had a toolmaker mate of mine try and put some knurling on it.  The steel is so well tempered and of such a good quality that even the tough knurling tool had trouble with biting into it.  I reckon having knurling on a long shaft screwdriver like this one is a good idea.  It would be way of getting screws out quickly.

    What prompted me to talk about screwdrivers is that I decided I needed a set for Torx  headed screws.  I am seeing more and more products that use them.  The sole Torx screwdriver that I had (a security Torx brand Number 20 specifically for the now old school IBM 8512 computer monitors) and the good old screwdriver bit sets are now not really cutting it.

    So I got hold of Ron Enright Tools in Auckland, which is where I got all of my CK screwdrivers, to see if I can get some for Torx screws.  I was recommended the PB Swiss range of screwdrivers by David.  He reckons they are the bees knees.  Maybe even the PBs knees (sorry, that was lame).  He gave me a good deal on the colour coded set you can see in the picture.  They turned up yesterday and they look beautiful!  Mmmmm…. Nice handles (although I think square is my preference), good looking (but functionality is more important of course), and all with individual serial numbers, something I have not seen on other screwdrivers.  It looks like I will get a lifetimes worth of use out of these things.

    That is enough talk about screwdrivers.  Time to do some screwing.

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  • Screws

    Alan Liefting

    Don’t you hate it when no matter how many screwdriver bit sets you have you will still come across a screw for which you don’t have a bit?
    And don’t you hate it that the sets come with tri-point but not tri-wing driver bits?

    Another great cartoon from xkcd.com
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