Musical keys

A child’s set of keys gets repaired in the workshop

It makes a nice change to repair something like a childs’ toy.  I know that if the repair works out, it’ll usually make someone very happy.  However, having just said that, the repair I’m about to discuss, didn’t bring joy for all…

First off, I’ll get a moan out-of-the-way.  Too many kids toys take too many batteries – it’s been like that since I was a kid.  This does two things; makes the toy expensive to own and damaging for the environment when the batteries expire.  Now, I know there are some very cool kids toys that rely on sophisticated electronics to make them work, but manufacturers:  Please try to think harder about the toy’s overall impact on the environment and it’s in-life running costs.

OK, rant over.

On with the repair.  This kids-chew-musical-keys is supposed to mimic an adults’ set of car keys.  It doubles up as a teething chewy thing as well as an imitation car alarm blipper remote fob thing, that plays a tune.  Delightful.

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FixItWorkshop, March’19, kids car keys.

This set of keys had stopped playing a tune, when any button was pressed.  To some, that might have been a good thing.

The battery compartment contained two LR44 coin batteries.  These are found in many items and are readily available, if you know where to look, but are not commonly stocked in supermarkets, where I suspect most people buy batteries.

Taking the batteries out revealed some light corrosion on one cell, but no dramas.  The other one was corrosion free.  However, a quick test with the multimeter revealed that both batteries were kaput.

I usually keep a pack of LR44s (as one does) in case of toy key emergencies like this and luckily on this occasion, I had two shiny new ones to fit.  But, upon installing them, replacing the cover and pressing one of the buttons for the first time there was still no sound.  How odd.  What I thought would be a quick battery change had escalated in to a full toolkit situation.

Whipping the back of the key fob apart revealed a simple integrated circuit with the battery terminals, all in good condition.  The small piezo speaker was held behind the main circuit board and on closer inspection, I saw that one of the soldered connections had broken away from the speaker.

Solder repair jobs like this are difficult as excess heat can quickly transfer from the joint being operated on, to the whole component, causing damage if too much heat is conducted.  I had to be careful.

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After some careful soldering, the broken wire was reconnected, circuit board re-installed, casing screwed back together and batteries re-fitted.  A quick tap of one of the buttons then revealed musical joy.  After a couple of presses I then began to regret the repair…

Cost of replacement:  Not sure, £5 ish?  Cost of repair: A bit of soldering.

Another smoking Kenwood Chef A901E sorted in time for Christmas…just

Another Kenwood Chef gets the treatment in the Workshop

How about another Kenwood Chef story?  I know I’ve covered this machine a few times now, but I’ll try and make it as interesting as I can.  I just LOVE Kenwood Chefs.

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FixItWorkshop, December’18, Worthing, Kenwood Chef A901E on the bench.

A customer got in touch with me via the FixItWorkshop ‘contact us’ link asking if I could fix his family’s much beloved Chef.  While last in-use, it started smoking and smelling terminal.  How could I refuse.  I’m located in Worthing, but the customer was based in North London, quite a distance for a repair and would have been usually cost prohibitive using the Royal Mail.  However, using local drop-off points, carriers such as Hermes and DPD offer (slightly slower) courier services for about £7.00 one way, which starts to make more fiscal sense.  This is what we did.

I wish I’d taken a photo of the box the Chef came in, because the customer had clearly gone to a lot of effort to make sure it was well protected!

On with the repair.

The Chef has been in production many years and although they can often appear similar on the outside, they do vary on the inside, depending on the year of manufacture as small tweaks and improvements are made.  Evolution, rather than revolution, usually the backbone of any successful design.

The A901E is different from the previous A901 as it features an electronic speed controller, rather than a centrifugal affair.  While the later design is an improvement, it wouldn’t deter me from buying an earlier model; the improvement is small.

The A901E still features similar components to previous models which can and do fail, especially with age.  The subject here is about 30 years old, give or take.

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FixItWorkshop, December’18, Worthing, A901E, motor removed.

The motor on the A901E comes out quite easily; first remove the motor cover, remove the mains cable (disconnect first of course), remove the top cover, belt, then the four screws holding the motor in.  The motor then pulls down from inside, out through the gap left by the hinge.  Easy.

The motor circuit board showed traces of component catastrophe with dust and dirt left by exploding components.  Nasty.  Pre-empting the fault, I ordered a repair kit before I’d taken the machine apart, together with replacement feet as the ones on this machine were knackered.  The kit includes capacitors, resistor and triac as these are the main components that tend to fail.

These kits are available on eBay and are worth the money as they are often cheaper than buying the components separately and they contain instructions for newbies.  Here’s a little slide show showing the process.

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With the kit fitted, the motor re-installed, mains reconnected, the Chef ran well again, this time without burning or smoking.  However, all was not well as the speed control was a bit wobbly at lower speeds, which was just plain wrong.  Having worked on a good few Chefs, this problem is usually down to excess end-float on the motor spindle.  Working with the motor still in situ, the motor fan, which controls end-float could be adjusted with an Allen key.  Sorted.

Just the replacement feet to fit and after a quick clean-up, the Chef was reassembled, ready to go home.

A top tip for you.  If you intend to replace the feet on your machine and you probably should if they are old as they go hard or fall apart, then soak the area around the feet recesses with WD-40 or similar a day or so before as this will make getting the remnants of the old feet out, much easier.

Cost of a replacement:  £400 up.  Cost of repair:  £12.65 plus my time and tea.