The 6 Dollar Man - we have the technology

The title of this post goes back to Lee Major's TV series in the 1970's, adapted to reflect repairs to just one limb rather than the whole body! In other words, it's about a personal journey towards having a replacement knee fitted.  The procedure seems to be increasingly common now that ummm.... "mature" people are active for longer, yet the information out there can be overly technical, impersonal and not a little alarming.  I thought that documenting my personal experience of the process may assist others in making balanced decisions should they be in a future similar position.

A BIT OF HISTORY

I'm 75 now and still physically active but suspect it all started when I was at senior school in the UK.  I threw the discus for my school and province. The problematic left knee was the one which I used as an anchor when rotating in the throwing circle and it would occasionally flare up after competition.   It was shortly after emigrating to NZ in 1975 that I took up sailing at national championship level.  Hanging over the side of the boat to counterbalance it put a lot of load on the knees and this is when the problems became really apparent. 

1963 school team for county championships.  I'm middle row, 3rd from right

1980 - hanging over the side by my feet - heavily stressed knees

In 1981, I had my first surgery to stabilise a dislocated knee and whilst the decline was relatively slow, it was becoming more painful and less stable.  Like a true guy, I soldiered on until recent years when Jennie really started putting the heat on me to get something done about the problem.  As mentioned in previous posts, buying an e-mountain bike and covering some 2500 km on off-road trails in the last 15 months had some real benefits, as did losing 10kg from all the cycling exercise.

However, the time came when exercise alone wasn't enough and x-rays prompted a pronouncement from a local surgeon that they were "stuffed".  The NZ public health service is pretty effective overall but some regions have long waiting lists for particular procedures, including ours.  The surgeon commented that I'd done a lot to help myself and although he couldn't promise anything, he would see if the procedure could be carried out at a private hospital in another region.

THINGS MOVE RAPIDLY

A few short weeks later, I received a preliminary approval from the regional health authority,  then an email from Ormiston Private Hospital in the Auckland Region asking me to have new x-rays taken and to attend a preliminary consultation with an orthopaedic surgeon.  This was when the nerves really started but she really put me at ease with a no-nonsense description of the procedure.  Melissa also sails competitively as I once did, so that was a nice ice-breaker too.

The amount of pre-op documentation to be completed was substantial but efficiently handled by the admin team.  This is where things got interesting and may be of benefit to future patients!  The broad options for anaesthesia were a general anaesthetic or a spinal block, with additional sedative as appropriate.  Initially, being awake during surgery with all the sawing and hammering filled me with horror but this alternative offered a much faster recovery rate and without some of the known risks of general anaesthetic.  It was implicit that there would be absolutely no pain with a spinal block so that's the way I decided to go.  With an absence of pain, I also thought that minimal sedation would also be good.  Instead, the intent would be to play some music via my phone and earbuds as a partial distraction from noises which might resemble an engineering machine shop!  Fingers metaphorically crossed, I signed the paperwork and waited for the day, not without some trepidation.

HOW IT ALL WORKED OUT

An early check-in on the morning of the procedure, followed by visits from various members of the surgical and rehab team with yet more papers to sign.  Jennie and I were both impressed with how clearly explained it all was and delivered with grace and good humour.

Waiting to walk to theatre - more apprehensive than I look!

Just a couple of minutes walk to theatre to meet the near all-female surgical team.  The ones prepping me with the spinal block did their business, again clearly explaining how it all worked.  As I was laid down on the operating table, I experienced the one and only surge of genuine anxiety.  I was effectively paralysed from the waist down but the anxiety vanished as quickly as it had started.  The anaesthetist, Natalie; helped to get my music started at low volume - a mixture of favorite pop songs and Mozart, since you ask!

I was able to hear much of the conversations between the surgical team and the noises of surgery which were not off-putting because there were no accompanying sensations thanks to the block.  What impressed me the most was the relaxed, ego-free atmosphere and associated humour which is a hallmark of all genuinely high performance teams.  That culture is something I've been fortunate to be associated with for much of my working life and it's less common than you might think.  In what seemed like no time at all but was somewhere close to 1.5 hours, Natalie told me that they were suturing up and I'd be in the recovery ward shortly.  What a truly impressive team and being fully awake, there was the opportunity to thank them personally

With no side effects, the stay in the recovery ward was a very short one but the nurse looking after me asked if I'd like an iced lolly.  Wow, that lemon ice was the best ever and yet another example of the hospital team going the extra mile!

From there, it was to a private room with all mod cons including multi-channel TV, private bathroom and so on, with nursing staff making sure that I was completely looked after.  Within a very short time, I was sitting up in bed, eating a delicious sandwich whilst chatting with Jennie and some members of the surgical team. I guess the intent is to normalise the situation as soon as possible and having a spinal block certainly aids that.

Only an hour and a bit after surgery

Ice water circulating round my knee and pressure cuffs on my feet

All the meals were extraordinarily good, with an excellent range of options - something I wasn't expecting at all.

A beautiful fresh fish fillet and roast vegetable meal

After dinner, it was time to get out of bed for the first time, only a bit over 6 hours since surgery was completed.  A slightly worrying time but pain relief took care of that.  Just a short stroll up the corridor supported by a walking frame to build confidence.  The care by the nursing team at all hours of the day and night couldn't be faulted.

Not exactly elegant but pain-free!

After breakfast the following morning, I was disconnected from the pressure cuffs etc and allowed to visit the bathroom for a shave etc - another milestone.  Seeing the surgical dressing for the first time was quite a surprise. A very neat incision considering that it was a whole knee replacement.

A surprisingly small dressing

It was then time for a visit by the physiotherapist and walking the corridors with the aid of crutches.  Surprisingly tiring and walks were interspersed with naps and watching TV.  Helen, the physio; thought I'd acquitted myself well and we worked through the various rehab exercises that I'd need to do on discharge.  The photo below shows the use of a mini skateboard to improve knee flexibility - works a treat!

Skateboarding whilst sitting down!

Thursday was the day of surgery and it was now Saturday morning.  Before discharge, Helen needed proof that I could negotiate stairs, especially as we have a 2 storey house with both internal and external stairs.  She was a great teacher and going up and down the stairs between hospital floors was done safely, although I wouldn't be breaking any speed records.  With this last task accomplished, the paperwork was signed off and time to make the 2 1/2 hour journey home.  

THE REHAB JOURNEY

This brings us up to date.  Rehab involves exercises that can be uncomfortable, painful even but that pain can be managed.  After 3 days, I'm able to do without the stronger pain relief but they're available if required.  Exercise is tiring but I'm not sleeping particularly well, mainly due to lying in a position which is not my normal one.  Not a big deal in the scheme of things but this recovery phase is going to be tough. My wife Jennie won't put up with any slacking on my part which ensures that I stick with the plan.  She also regards it as payback for when the roles were reversed a few years ago when she had a hip replacement!

SUMMARISING

The entire team at Ormiston Hospital are worth their weight in gold.  Consummately professional, conduct themselves with humility and no egos on display - easy to relate to.  Systems and processes are absolutely top notch.  It was the American productivity improvement guru W Edwards Deming who said, "If you have great people and poor systems, the poor systems will win every time".  The Ormiston Team have got it right and I owe them a big debt of gratitude.

For anyone facing surgery now or at a future date, I hope that my personal experience shows that it doesn't have to be a scary process and that options like a spinal block for some types of surgery offers substantial advantages.

On the road to recovery - stair runs

Travels in the Tropics

After an uncharacteristically wet NZ summer which continued into winter, Jennie and I were looking for a midwinter break somewhere warm and sunny.  One of our favourite places is the island of Rarotonga in the Cook Islands, approximately 3200 km NE of NZ.  It's only 70 sq km in area without the commercialisation of places like Hawaii or Tahiti.  A great place to just chill and eat fresh food.  The Cook Islanders themselves are wonderful - laid back, great humoured and really friendly.  They have a long association with NZ and are free to travel and work in NZ. Money is the NZ$, English and Cook Island Maori spoken so it's easy to fit right in.  Flying time is a bit either side of the 4 hour mark depending on conditions.

Rarotonga - Muri Lagoon in the foreground (file photo)

It's been 10 years since our last trip there and 5 years prior to that, we made friends with a couple from Wellington in Rarotonga.  Since then, we've stayed in touch annually and spent a long weekend doing stuff together somewhere in NZ.  Meeting up in Rarotonga seemed appropriate this time.  A nice, comfortable flight in an Air NZ 777-ER, pick up a Mitsubishi Colt rental car and head for our accommodation at Muri Lagoon, less than 30 minutes from the airport.  Most of the vehicles are second hand "grey imports" from Japan and the Colt was no exception.  The Colt is hardly a design classic but it is surprisingly roomy and absolutely miserly in its fuel consumption.  You'd swear it was actually making gas!  The national open road speed limit is only 50 km/hr which also contributes to good economy. The only downside was an in-built GPS with a map of Japan and a rather strident female voice in Japanese.  It took some time to figure out how to disable it without resorting to beating it to death!

Mitsubishi Colt  - hardly a design classic but incredibly economical

Our friends were picked up from the airport and ferried to different accommodation about 20 minutes drive away from us so the first afternoon there was spent exploring our immediate surroundings and chilling in the loungers on our waterfront villa.

Evening view from our lawn - tough but someone has to do it!

The effects of Covid on Rarotonga's economy were still apparent.  Lockdown in NZ, Australia and other countries meant that virtually all their income dried up at a stroke. The sealed roads round the island were in quite poor condition in many places, almost certainly due to austerity measures .  However, crews were out patching the worst craters whilst we were there.  I guess that the heavy rains in the Southern Hemisphere thanks to the La Nina weather condition didn't help either.   Our villa was advertised as "de luxe" accommodation.  It was located in million dollar surroundings but could best be described as "tired".  Nothing seriously wrong but suspect that there had been a lot of deferred maintenance.  It was still acceptable, but certainly didn't meet our expectations of a de luxe experience.

Dawn from the lawn - watch out for falling coconuts!

The next morning didn't start well with me taking a tumble on uneven ground and twisting my knee which is already scheduled for a bionic replacement.  However, it wasn't as bad as it could have been although kayaking, swimming and longer walks were wisely removed from the plan.

We caught up daily with our friends to do some exploring, or simply to eat, drink and be merry.  Fresh fruit and fish on the island is absolutely delicious.  Imagine plain old fish and chips being made with Albacore tuna - absolute heaven!  The cocktails, both alcoholic and alcohol free were pretty special too.

Happy Hour in so many ways!  Mike, me, Georgina and Jennie

No trip to Rarotonga is complete without a visit to the Muri Night Market to eat locally prepared food of all types.  Great value for money in terms of quality, quantity and price.

 

Getting in early at the night market for a feed

Jennie enjoying chicken satay with rice and salad

My spiced prawns with mango rice and salad.  Almost too many prawns to eat (almost!)

During lunch at a cafe in the main town of Avarua, we spied a sign on the wall of the restrooms which was delightful.  Perhaps it was gently poking fun at all the oh too serious and politically correct nonsense about diverse gender recognition or whatever it's called.  For goodness sake, we're all human beings, whatever our persuasion!

Nailed it!

Driving round the island one afternoon, we saw a bunch of people gathered by a sea wall.  Wondered whether there was a pod of whales passing by so pulled over.  It turned out that they were waiting to see the afternoon inbound flight from NZ as the runway end was just metres away  It wasn't quite as low as the YouTube videos showing landings at St. Maarten but I did manage to get a couple of shots.

Incoming.....

Not far off the deck at all!

A trip to the local museum was worthwhile and the displays were really informative.  I was really taken with a huge mural of a Polynesian voyaging canoe of the type used when the South Pacific, including NZ, was first being settled.  Those early settlers had supreme navigation skills, as well as big balls!  What is slightly concerning though is that the population is suffering a current annual net loss of 2.88%, presumably young people heading to NZ for better job prospects.

Early Polynesian voyaging canoe

There was also a smaller sailing canoe on display, presumably just for coastal waters.  I just loved the colour of the timber it was built from, its lines and the bird carving.  I wondered whether the carving might be a stylised Frigate Bird which is one of the indicators which the Polynesian sailors used for navigation and land over the horizon.

One of the ornate hulls of a small(ish) sailing canoe

Gorgeous bird carving

Sitting on a bench in Avarua's main street is great for people-watching.  The most common form of transport are step-through mopeds of Chinese or Japanese origin.  Until 2020, helmets weren't mandatory but that's now changed although we did see a few ladies with elaborate hair styles avoiding their use!

The most common transport mode on Rarotonga

We stopped off briefly at Avarua port to see what was going on but it was pretty quiet.  However, there was one inter-island workboat with a massive crane at the stern which seemed out of proportion to the rest of the vessel.  I guess versatility is the key word for work in the islands.

A seriously large crane on this workboat

As you might expect in a tropical environment, plants grow like crazy and the variety of attractive plants is bewildering.  Here are a couple of examples.

Cordyline variety (I think)

Mixed varieties

Despite Rarotonga being a tourist mecca for NZ and Australia, it's not over-run with people.  There are plenty of deserted beaches like the one below with safe swimming inside the reef.

Idyllic surroundings

Local store and laundry in one of the villages

All to soon, it was time to return to NZ.  With my injured knee, boarding the Boeing 777 in Rarotonga wasn't going to be a major issue as it was only a short walk to the plane but one of the Rarotongan Air NZ employees noticed that I was using a walking pole and arranged priority treatment.  This involved being pushed in a wheelchair across the tarmac and up a ramp.  Wonderful service although I felt a bit self-conscious!  They also arranged for us to be met at Auckland where it's quite a haul from the gate to baggage reclaim.  There was an electric buggy waiting for us which helped no end.

In a wheelchair waiting to be wheeled to the plane

Aere ra (goodbye) Rarotonga!

That's all our travels done for the time being as a long overdue knee replacement is scheduled for the end of the month.  With the warmer months coming, the focus will be on rehabilitating as soon as possible so that we can be out doing cool stuff asap.  Jennie is really looking forward to making me walk decent distances on crutches on a daily basis as payback for when I made her do the same after her hip replacement a few years back.  Sigh.... 

It's being done at a private hospital but you can still call me the Six Dollar Man 😄

A near miss and some good stuff

NZ has had more than its share of bad weather in 2023 and the peninsula we live on has been directly in the firing line for most of the storms.  Although there has been an improvement in recent years, power cuts often occur due to trees falling on the power lines.  Outages these days typically last from as little as a few minutes to half a day or more.  We have a gas BBQ on our covered deck which is handy for cooking when we lose power and have various gas and battery lights so that we can see ok at night.

One backup power source we've used for a few years is a 12v sealed lead acid battery which is about half the size of a motorcycle battery.  We keep it in the basement garage, connected to a small solar panel fixed to the outside wall so that it's always fully charged.

Solar panel supplying power to the 12v battery

The battery is light and easily transportable with many uses.  Typically, we use it with an inflator for our vehicle and cycle tyres (don't trust gas station pump accuracy!), fish finder power on the boat, attaching to an LED panel as a handy portable light source and charging phones via an USB connection when the power is out.  Sure enough, we lost power during the last storm which coincided with me being low on mobile phone charge.

12v 7AHr replacement battery and phone charging lead with better connectors

A quick trip to the garage with a torch and connected the phone to the battery via the lead.  At that time, the battery connection was via crocodile clips.  A few minutes later, there was an odd smell and I went to investigate.  The battery was hissing and smoking, with the casing horribly buckled.  One of the crocodile clips had shifted, causing a dead short across the terminals.  A lucky break to have smelled something amiss and the outcome could have been a lot worse.

It was a salutary lesson to make more reliable connections and after buying a replacement battery, all the connections were changed to shielded bayonet types with heat shrink reinforcement.

On a more positive note, I recently mentioned the design and commissioning of more stained glass windows for our house at the end of THIS POST .  The subject was a native Tui drinking nectar from a plant in our garden that I'd taken a photo of.  We'd engaged a local craftsman to make a window in stained glass from the photo and last week, it was ready for collection.

The glass ready to install in a bedroom

It's not designed to replace the clear glass already in the window, but to nestle up to it, leaving a small air gap.  I'd made a template for the craftsman to build it on but it was still an anxious time in case it was a fraction too large.  Needn't have worried though - a perfect fit.  The only worry was teetering on a stepladder and holding it in situ whilst fixing it permanently in place.  It looks absolutely fantastic, both in sunlight and moonlight.  It's wonderful that there are still people around who practice the traditional crafts.

Safely installed with no glitches

The week concluded with a pleasant Sunday run with members of the Whitianga classic car club to a beachside restaurant for lunch.  A great bunch of people with a wide age range of cars.

A good spread of ages

Parked up for lunch

The reality of classic car maintenance

We bought the MG nearly 2 years ago to actually drive, as opposed to spend time restoring it. This was particularly relevant with both Jennie and I being in our mid-70's.  The excessive but enjoyable time spent building drag bike engines a lifetime ago is best not revisited to maintain matrimonial harmony.  Buying a car with most of the restoration done has really paid off.  The upside of most classics is that that they're not all that complicated to work on, don't need too many special tools or computer-based diagnostic equipment.  The downside is that they need a bit more maintenance than modern vehicles.  Much of that work will be D-I-Y as most main line auto shops won't want to touch them as they all have their quirks or special requirements.  Even our village garage owner who is "old school" and a near neighbour makes a sign of the cross when I drop in, even for a social chat. 

Ever since we took ownership, the engine has had a slight oil weep from one of two tappet/pushrod covers. Slight enough for just an occasional drip onto the strip of vinyl sheet I have under the car in the garage to protect the carpet.  Yes, our basement garage has carpet, albeit the proper heavy duty industrial grade.  I can see the shaking of heads now but the garage was a once handy place to stick the multiple mates of our kids and similar when they were looking for a place to lay their bodies overnight. Even grandkids when they all descended at the same time.  Invasions of that magnitude are largely a thing of the past now.

Right, getting back on track with the oil weep......

It wasn't a big deal but being an anal retired professional engineer, it was like a slight itch that you couldn't scratch.  It would have been fixed earlier but for the fact that the carbs, heat shield, inlet manifold and exhaust manifold all have to be removed, then replaced for what is an hour's work at most to replace the leaking gasket.  Having never done the job previously and not wanting to cock it up big time, I reckoned that would take up to a couple of days being ultra-cautious.  A poor return on my time when I could be out driving it.  

The leak is buried under all this plumbing - bloody typical!

The North Island has suffered an extremely wet autumn and winter thanks to the La Nina weather system so it was an opportune time to bite the bullet and prepare to do the job in the face of an indifferent weather forecast.  Both of my repair manuals gloss over the job, but the MG Experience website forum had multiple posts on how to avoid further leaks so clearly, a bit of care was needed.  All relevant parts were purchased online, including some contingency materials just in case.  The good thing about owning an MG is that parts are relatively inexpensive and available.

First job was to remove the air cleaners and carbs.  I'd done this before to get the carbs rebuilt, including making a simple jig to stop carb linkages and springs from flying off and disappearing into dark recesses.  Removal of the heat shield and inlet manifold was also straightforward, even though it was uncharted territory.  Nuts, bolts, spacers and washers all went into labelled ex-catfood plastic containers to stop the Garage Elves from making them disappear without trace.

Carbs and inlet manifold off, just the exhaust manifold to pull clear

I wasn't looking forward to disconnecting the manifold from the rest of the exhaust system as access to the retaining nuts was a hassle, best accomplished from under the car.  Fortunately, the whole assembly could be pulled clear by a few centimetres and supported with a jack under the car.

The weeping tappet cover ready for removal

The front tappet cover was weeping from both the retaining bolt and from the joint surface with the engine block.  It virtually fell off once the bolt was removed, indicating poor adhesion between the mating surfaces.  The red sealant (see photo below) looked suspiciously like a previous owner had used Red Hermetite.  I remember using this on Triumph motorcycles back in the 1960's.  Triumphs of that era were notorious for oil leaks and the use of Hermetite did little to improve the situation.  To use a succinct and somewhat unambiguous description, the properties of snot as a sealant would have been an improvement.

Not much adhesion or sealing on display.........

The mating face on the engine block

Fortunately, members of the website forum previously mentioned had extolled the virtues of Hylomar Universal Blue jointing compound.  Developed by Rolls Royce for aircraft and turbine applications, it has a serious pedigree.  Not cheap, but a tube was purchased in advance.

It can be seen in the photo above that what remains of the cork gasket is narrower than the flange of the cover and the mating face on the engine block.  Several forum members recommended not using the official gasket and making a wider one from rubberised cork sheet.  Which is exactly what I did......

A pristine gasket cut from rubberised cork sheet

All mating surfaces were wiped with methylated spirits to remove any oil contamination and Hylomar was applied to all surfaces.  The torque setting for the retaining bolt was a miniscule 5 lb ft - well below the minimum setting of most torque wrenches.  However, an approximation given by one of the forum members was to gently tighten the bolt whilst grasping and gently pulling the vent pipe on the cover.  When the cover no longer moved about, that was pretty much spot on.  Easy peasy - worked a treat.

Front tappet cover in place with new gasket

The rear tappet cover showed no sign of weeping.  I spent a moment or two wondering whether to replace that as well but decided to leave well alone in case Murphy's Law decided to put in an appearance.  Reassembly of the plumbing and fuel system was simply a reversal of disassembly, with the proper torque settings and use of Hylomar on critical mating faces.  

All assembled and ready for a test drive

A 40 km test drive revealed no weeping at all and interestingly, there was little or no smell of hot oil.  Even though it was a weep rather than a leak, the proximity relative to the exhaust manifold must have previously carried the odour back into the cabin.  The real test will be over the next few hundred km but there's no reason to think that the weep hasn't been fixed.  There's also a slight weep from the overdrive unit but as that involves grovelling under the car, the inclination to fix that hasn't reached the "scratching the itch" stage yet.

Although the 1 hour basic task took most of the weekend to accomplish because of all the disassembly and reassembly involved, not to mention an abundance of caution; it was nonetheless an enjoyable experience gaining more knowledge.  Every day is a school day!

There's actually another reason I wanted to get the MG in pristine condition for the warmer months ahead. In a few weeks, I'll be having a replacement knee joint which will keep me out of action for a while.  Not looking forward to it one bit but it should address something which has become increasingly problematic over several decades.  New horizons beckon!

Test drive - Oamaru Bay, Coromandel Peninsula.  Someone has to do it!

And now for something completely different....

It's funny how statements which you make come back with a vengeance and bite you again!  The last photo on my May 9th post showed a banner which was a tongue in cheek version of John F Kennedy's speech about going to the moon.  The banner read "We do this not because it was easy, but because we thought it would be easy".  This certainly applied to a recent activity!

Our 11 year old granddaughter Georgia started intermediate school this year.  She's a smart cookie and is in an accelerated class where the work is set up to challenge them.  Each student was recently asked to come up with a project, implement it and report the results.  Georgia had seen something on power generation using a waterwheel and thought it would be cool to see how power output changed with water flow and gearing.  All this because they have a small stream passing through their property!  She asked her dad Kerryn (our youngest son) what he knew about the subject and the answer was very little. As the lead time for completing the project was only a couple of weeks or thereabouts, he was straight on to me to see what I knew about the topic. The answer was Sweet Fanny Adams, apart from understanding the physics and engineering principles.  The short time deadline was going to be quite a challenge.

A brief discussion was had over the phone with Kerryn, with the thought that the 3 generations could work together as well as Georgia conducting the experiments and writing the report.  Wherever possible, everyday recycled materials could be used.  How hard could it be? And then the catch.... would Nana and Granddad mind doing the 400 km round trip this coming weekend to help make it all happen?  Immediate thoughts went back to the first paragraph of this post - no pressure then!

The best part of day one after the phone call was spent on YouTube and other sources learning about different types of waterwheel and it became quickly apparent that an undershot wheel was the only practical option because their stream was relatively shallow.  Next step was to see what resources we already had which might be useful for constructing a waterwheel.

Jennie had an old bicycle which had been unloved and not ridden for 3 or 4 decades.  That might be a useful source of big sprockets and maybe a chain.  I had an alloy bike rim which we inherited with the house decades ago and a quick bit of dismantling got underway.  I also dug out some threaded bar, stainless tube and other bits and pieces which Jennie previously referred to as hoarded junk, sigh...  I also requisitioned one of Jennie's nylon chopping boards to make thrust washers for new axles. It wasn't strictly theft as it had been re-purposed some time ago as a fishing bait board for the boat!

Collecting possible components with only a vague design plan at this stage

Next step was to head to the village transfer station and see if there were any old bikes with sprockets of various sizes.  One was spotted under sheets of corrugated iron in a pool of disgusting water.  Quite a job pulling it out in those unsanitary conditions.  Good value for a couple of bucks!  A quick bit of hacksaw work to get the sprocket and chain off, followed by soaking the chain in kerosene to loosen up the rust.

Raiding the village dump for more sprockets and chain

A call with Kerryn revealed that he had some plastic downpipe which could be made into vanes for the undershot waterwheel.  He built a shopping list of bolts and other fittings, plus our one and only purchase of a new piece of equipment.  We had intended to use a car generator from a wreckers yard but found a brand new mini-generator online at much the same price we would have paid for a car component.

Mini 12/24v DC generator

Armed with tools, boxes of bits and fingers crossed, we set off on the 200 km trip. I got stuck in and made a large sprocket carrier to the bike rim which was going to carry the vanes whilst everyone else departed for Georgia's Friday night hockey match.  Next morning, another family departure for our grandson's rugby match whilst Georgia and I measured and cut up the piping for the vanes.  She'd never used a jigsaw before so we had a short practice and then onto the real thing.  She was outstanding and made beautifully straight cuts.

Georgia splitting the piping with a jigsaw

After splitting the pipe, she then marked the halves up for cutting into individual vanes.  The width was a pure judgement call on our part, having seen the professional wheels on YouTube for serious domestic power generation. Let's call it an educated guess.....

Using a jig for marking out the individual vanes

With weekend school sport taken care of, I made up the axle assembly whilst Georgia and her dad mounted the waterwheel sprocket then drilled the wheel rim and vanes and bolted them up.  Another judgement call about how many to use, just using years of accumulated engineering experience and the obligatory crossing of fingers.

Bolting the sprocket to the carrier

Fitting the vanes

The completed wheel

With the axle in place and the wheel spinning freely, a support frame was made from timber by Georgia and her dad, with adjustable legs from threaded bar, then carrying it to the stream to see if it actually worked - the real acid test!  A brilliant outcome with 60 rpm being attained in a faster part of the stream.   I should mention that the stream is at the bottom of a steep gully so getting all the kit there and back wasn't a straightforward exercise by any means!

Happiness is a spinning wheel

Sunday dawned with the main goal of hooking up the generator.  It was spun up at various rpm using an electric drill to obtain voltage output characteristics, particularly at speeds that the waterwheel would rotate at. A good confidence boost as it worked just fine.  A mount for the generator was made, using clamps for chain alignment and tensioning.  With time being a precious commodity, a rudimentary coupling was made to mount the generator sprocket. Not a perfect solution but adequate for the experiments to be run.

Setting it all up

With time getting on, Jennie and I had to make the 3 hour trip home whilst Georgia and her parents headed for the stream again to test how the completed rig worked.  Very much in our thoughts on the way home and a hope that I hadn't lost any engineering mojo with that dodgy coupling!

Got a message soon after we arrived home, complete with videos and photos - an outstanding success in every respect, apart from the chain periodically jumping off the sprockets.

Measuring the output voltage with different sprockets

Documenting the results

Georgia hooked up with fairly lights!

An immensely satisfying weekend for multiple reasons.  The pleasure and fun of the family working brilliantly together across 3 generations, pride in seeing how hard Georgia worked and her focus, overcoming problems on the run with very tight timelines plus all of us learning new stuff.  None of us are ever too old to learn new things, it's what keeps us alive.  It really doesn't get any better than that!  The future is in good hands with young folk like Georgia around.

Postscript

Georgia has to complete her report and submit it this week.  Her parents and grandparents might be a teensy bit biased but when it's finally assessed, it's hard to imagine that the outcome will be a poor one!

Addendum late June: Georgia has just given her oral presentation at school and was given an "exceeded expectations" result.  The project also won a silver rosette at the regional science fair.  So darned proud of that young lady!

Proud Dad and daughter