Golf Ball Adapter

 Hi

 

This post follows on from my previous one on Yarra cleanup

 

In recent years, golf balls have been identified as a source of water (sea, ocean, river) pollution, and lots of them have ended up in the water where they rot and do damage to the environment. Alex Weber has highlighted this pollution in the USA where several prestigious courses including Pebble Beach are right next to the sea.

1: Golf courses upstream from Dights Falls

 

Locally in Melbourne, the Birrarung  / Yarra Cleanup Mob have also noticed golf ball pollution, and in cleanup days have removed hundreds from the river bank near Dights Falls. They've scheduled a "Golf Ball Pollution Art Day" for tomorrow, and I will be there with a contribution. 

2:  Tetrahedron from golf balls

 

That contribution is a 3d printable adapter which turns 12.7mm diameter rod (ie from timber or steel) and golf balls into a Geomag style construction kit. Note that a screw hole needs to be drilled wherever an adapter attaches to a ball! 

* Here is the thingiverse link

* Visit this site to see just what can be made with Geomag, and I have posted a few pics below.

3. Geomag Bridge.

4. Geomag Eifell tower.

5. Geomag football stadium.

6. Geomag helicopter

Geomag Sphere

 After making the adapter, I recalled that I had a similar (node-and-stick) construction toy called Makit Toy as a child. A bit of research revealed this to be similar to Tinkertoy, but Makit Toy is what I remember. The kit might still be at my parent's house.

7: Makit Toy Parts.

8. Makit Toy Parts and box

9. Tinkertoy

Anyway I remembered some of the Makit Toy construction methods (such as

* Brown rods have sawn ends to let them fit and spring tight in node holes (see 7)

* Red rods slide through node holes and can rotate in them (7 and 8) . If they need to be secured in a node hole, a steel bushing (see 8) can be added)

and started using them in construction. If you drill a 12.5mm hole in the golf ball, the adapter can be done away with!

10. Makit Toy type tricks: Reduced diameter bar (red squares) allows the rod to rotate, slit in rod end allows rod to be inserted and holds rod in place.

11. Pivoting rod

12. Larger holes in golf ball allow 12.7mm rod to fit in directly.

Update 18/2/2023

Done and dusted, here are my pictures from the Golf Ball Art event. We just wrote or made what we wanted from Golf balls that had been rotting near the river and it was fun. I gave a brief demo of my "tech". Danella called it wizardy and I am very flattered!

Oh, and I almost forgot - there was lots of bending to do this stuff and I got a really sore back by writing stuff with Golf balls for only one hour! This contrasts with riding my recumbent for about 8 hours to cover 150k last week - there was no pain at all, just tiredness.

Yarra Cleanup

Danella leads the troops.

Lots of this stuff around, plastic in trees.

Nice views and some companionship while picking up the rubbish.

Golf ball about to be mined.

"The big stuff" an old hose, dead batteries, and old cushions full of silt all went on a big gate.

Lots of golf balls. Danella is running a workshop to work out what to do with them in February.

Robbish I collected

Danella and Des on the way out,

and back to cars and bikes.

 Hi, today I attended a very enjoyable cleanup the Yarra day organised locally by Danella who happens to be a force of nature. Went for a swim (maybe 600m or so) at Deep Rock in the Yarra afterwards with Danella and her mates which was very nice and sociable. We saw a wallaby, others saw other creatures which I didn't, I am possibly slightly blind without my glasses! 

This mob's activities can be followed on the instagram thingy, here is the link, https://www.instagram.com/birrarungcleanup/ 

Update Jan 27 2023

I did a bit of googling about golf ball pollution (see this link) and found that its a thing. The article I linked to is about ocean pollution, and we are talking river pollution here, but there's some relevant information there.

Some golf balls ending up as large scale sculpture. More on this next time!

 

I have now done my own citizen science project and can confirm that

Yes, golf balls do sink in fresh water and

Because their diameter is 42.5mm, their radius is 21,25mm which means

Their volume was calculated at 40.2 cm3, but I reckon its bit less because of the dimples, say 39cm3 and I weighed them at

185g for 4 , or 46.25g each.

So yep, the calcs are in, they should sink!  The fresh water they displace will weigh about 39g because freshwater density is 1, while the salt water (density 1.025g/cm3 they displace will weigh about 39.975g so they will still sink even in the denser seawater. And most of that info is here in the wikipedia page so it was a waste of time working it out.

If you have stayed awake you are rewarded! This is looking away from the river at Deep Rock with my bike foreground and a hot air balloon landing background.

Next: The art day, click here.

Buckley's ride preview and training

 

The stats

Rubbish loaded in tailbox

My bike at Deep Rock. I went for a couple of swims here. I think they call it cross-training

Hi

As I have done several times in the last few years. I have signed up for the Audax Buckley's ride which is Round the Bay (Port Phillip Bay) in a Day in Bike Network Parlance.  Last year, my bike broke in the rear frame, but I have finished 2 separate 200k audax rides since then, one to Portsea and return, and one to Anglesea from Werribee and return.

I have been training on the hilly Kew Boulevarde, and consider myself quite well prepared. I am using my Garmin as a basic speedo, trying to keep over 10 kph up the hills, and recording trip length and speed when I can.

Today I was inspired to pick up rubbish by some local cleaner uppers, some of whom swim at Deep Rock, on the nearby Yarra River. I have deducted a minute from today's time for every piece of rubbish I picked up!

The weather is shaping up to be warm for the ride, that is 32 degrees, and in my training I have only just stopped my face from burning by frequent application of sunscreen. I plan to use a buff for the actual ride, I think that's much more robust as sun and dehydration protection. Wish me luck! 

For part 2, click here

Activities on the day before the ride, with Pete and Pete, I.......

fixed bikes like this Giant Liv for refugees at Wecycle.

 

Steve Nurse

Dodecahedron from Bike Rims

 

1. Progress to date - 3 rims drilled, and 3 edge joiners made.

2. Detail of rims joined and drilled. Joiner is ......

3. this which is a piece of 25mm round dowel timber. Surrounding it in black is a drilling jig which ensures holes through are correctly positioned.

4. Dowel cutting. There are 30 connectors to be cut so this setup was worth it to cut quickly and accurately. Plastic pipe is another option but I wasn't sure about cutting it with this setup.

5. Typical source of rims. This is a discarded De Carlo bike with the 27" steel rims used in this project. Its resto is documented here. The now-installed 700c aluminium-rimmed wheels are lighter, easier to get parts for, and brake better the the old 27's.

6. Layout diagram for wheel drilling and drilling jig shown in 2.

Hi Good progress on this project in the last few days. I have been thinking about it for ages and finally got working on it a few days ago, after gathering enough wheels and buying some dowel to make the edge joiners from. Principles to make this sort of thing are outlined in my article for the Australian Mathematics Education Journal which is here (official site) and here (full version through researchgate). Also, this post describes building the same thing in beer cans!

Basically, any old circle can be made into a polygon (pentagons shown here) , and from there into a platonic solid outline (dodecahedron started here). 

The rims I am using are mostly 36 spoked / holed, which is not divisible by 5. This means some extra drilling has to be done, and I worked out a diagram for the drilling, which is not too hard.

Another donor vehicle. This Apollo bike has frame damage at the head tube and so is being ripped apart. I will take its frame to the recycle depot soon.

All the wooden dowel pieces have been drilled and varnished now, and this was the drilling setup. The jig stays in the vice, then the dowel is inserted and drilled. Quite quick.

Rims have all been despoked, and I've numbered the spoke holes so I know where to drill.

The top rim in this shot has been drilled, the rest are marked up.

Update 2/1/2023: Happy New Year!  And hi ho, its back to work we go.  Quite close to finishing now, I've extracted all the 27" rims I need, and just need to drill 9 of them with 5 equispaced holes before assembly can start. Quiet time in Melbourne, I went for a 7am swim in the yarra which was nice. 28 degrees C already, quite warm.

Assembly while watching "Rivers" on the TV. If it was all put together, it would be too big to get outside.

All the bits

Centrepunch done, drilling follows next.

22mm spacing markup

11mm spacing markup. A spoke nipple is used to make a centre point for one leg of the dividers.

 11pm update!

Close to finishing now. I smashed through some rim marking up, rim centre punching and rim drilling this evening so I could start assembly. About 1/2 of that is done but I came across a drilling mistake, and will fix that and keep assembling tomorrow.

 

Update 3/1/2023 Finished now!  It was just as well I stopped last night as there were 2 drilling mistakes that needed correcting. Today I've drilled holes in the correct spots in 2 of the rims, assembled half-sections inside, then assembled the 2 halves of the dodecahedron outside. 

I kept a lot of the screws loose until the last screw was in, which was just as well, as there was a bit of a fight to get the last screw in. Properly marking out the first 3 rims might have helped.

The selfie photo was a bit of a challenge, as there is a 12s time gap from pressing the button on the camera to the photo being taken. During that time I needed to slither my 62 year old body into the thing. I tried this twice and banged my head on it on the 2nd attempt!

As you can see the back garden is a bit crowded with moderately sized bike rim sculptures, and the tetrahedrons will have to go!  The big tetrahedron folds flat at least! It is described in previous posts here and here. Very glad my late wife Chistine got a laugh out of it!

 Update Jan 4

Overnight I did some calcs on how big the dowels have to be on platonic solid structures like the one I've made, and the results are shown above. The size depends on the shape concerned (due to its dihedral angle ) and  the rim width and geometry. My dowels seem to be undersize, but I think because of the rim rounding I got away with it.

The last pic shows a modest sketch of what's next, or what could be next. I've already established that 3 rims can be bolted together to make a larger side, and by putting 15 sides together, a part icosahedron could be made. this could be a good greenhouse or cubby house or chillout tent. Even larger would be a 6-rim-per side part icosahedron.

Regards  Steve Nurse

Final Version of research published

 

Hi

The final version of my article "Circles for Maths, Art, Play and the Circular Economy" has appeared on the Australian Mathematics Education Journal website, and I have added the article to my Researchgate profile, so it can be downloaded here.  

The article talks about using items that may otherwise be scrap for sculpture and maths education.  I am now working on a project to make a dodecahedron from bike rims, wooden dowel, screws, and washers. It uses techniques described in the article, and I will be writing about progress in the next few days. With me luck!

The Art of Dating

 Hi

A short while ago I posted "Sorry Bettina Klussman" about my very trepid, very tepid  steps back into the dating game, after my wife's recent death and 30+ years of marriage. That was then, and this is now, a whole 3 weeks down the track.  

I haven't slept very well lately, so I thought I'd put some of these ideas down to get some of them out there, so I can process them I guess.  

The whole thing is like I am an atom, and have been locked up in a molecule for a while, and then the molecule gets busted, and I am an individual atom again. Because my chemistry is now different, I now react differently to others, have license to be in different places and situations, and so things have changed.

Firstly I don't seem to have too much trouble meeting eligible partners (mature women in my case) and starting chatting to them is a strange sort of dating game. I'm only just learning the rules, and coming to the conclusion that I'm doing ok by old fashioned methods and not relying on dating apps and other such things. It probably helps that its Christmas and there have been quite a few events on in the last few weeks. I'm optimistic.

Anyway, euphemisms abound in the dating game, and I said to one lady "I wouldn't mind hanging out with you at the bike shed and could teach you some bike mechanics" which actually meant from my point of view "I quite like you, do you want to go out sometime?"

And similarly, a lady I got talking to at a caf had said, "Oh, I might drop in here for brunch over the next few days, I might see you then". Which I think meant the same thing.

Caf's are quite a good thing. Once you start talking, you can skip all the hullabaloo about asking for a first date and pretend you are already on one!

Lastly there is the mobile phone, an essential tool for the aspiring dater. You have to accept whatever form of communication your potential partner wants to use, and sometimes that's a volley of text messages where a simple, shorter phone call (ie actually talking) might do. So recently I was out training on my bike and had to duck under a tree to reduce the light to read and send text messages. (Yes my phone competency is about as good as that of a 6 year old child, maybe worse) But messages got through and we met up and had a good time. So still on trainer wheels with this sort of thing but the training wheels have been oiled.

Best Wishes Steve Nurse

Prepint Released

 

Hi

Just now, I have posted a preprint of an article on building sculptures from everyday objects and 3d printed joiners. It has been approved, edited and will shortly appear in the Australian Maths Education Journal, issue 3 of 2022. Anyway, I wanted to move on and get it published, so here it is on Researchgate.  I will replace this with the properly formatted and citeable version as soon as the journal itself is released.  The article gives an overview of my work joining cds, drink cans, bike rims and other miscellaneous items together to form regular and other polyhedra.

 

Regards

 

Steve Nurse