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A reader writes:

I’ve got a couple of cats, had ‘em for a couple of years. I have trouble motivating them to chase their toys, ping pong balls, etc - it works once or twice a week, but otherwise they just ignore it. So I’ve decided to bring out the big guns and get a laser pointer.

It seems they’re much harder to get in Australia since all those airplane shenanigans, even though I hardly need a galactic-range pointer.

Was wondering if you had a suggestions for where to nab a laser pointer appropriate for kitteh?

Jack

It’s still pretty easy to buy your basic button-cell keychain laser pointer from electronics stores here in Australia. I think there might have been a brief drought when the new Think Of The Children Or The Pilots Or the Puppies Or Something OMG JUST BE AFRAID EVERYONE law was passed, while the stores made sure that the humble cat toys they were selling yesterday hadn’t suddenly been transmuted into illegal death rays.

But basic laser pointers are easy to find now. Here’s one at Altronics, here’s one at Jaycar (Jaycar have several other options, too).

[There are cheaper pointers on eBay, from sellers who at least say they’re in Australia, which means they shouldn’t be sending your purchase through Australian Customs to be confiscated by our ever-vigilant protectors. People may still be selling cheap pointers at the markets, too. If you believe price equals quality, on the other hand, note that the writhing transporter-accident creature that absorbed both Dick Smith Electronics and Tandy (Radio Shack) in Australia will be pleased to sell you a keychain pointer for $36.98 - at “DSE” here and at “Tandy” here!]

Altronics and Jaycar both want $AU14.95 for a bloody keychain pointer, which is of course a frankly insulting price. For little more than twice that much at current exchange rates a nice man in China will sell you a whole non-contact infrared thermometer, that incorporates an aiming laser. But which I’m sure will whistle through Australian Customs, just like all of the “laser-guided” circular saws, ultrasonic distance measurers, scissors, et cetera.

I chose not to choose a $15 keychain laser. I chose something else.

This prison-shiv of a laser pointer…

…took a lot longer to photograph than it did to make.

It’s pleasingly bright at around 25mA current - much brighter than your standard button-cell cheapie, but not bright enough to pose any real eye hazard. It has an egg-like shape that feels good in the right hand, with a nice clicky steel switch-bar under the thumb. It has adjustable focus, so you can widen the light out into a splodge of quantum speckle at will. And it had a total parts cost about the same as the abovementioned stupidly-expensive keychain lasers. You could easily make something similar for less than $10, including the two AA batteries.

(It’s quite hard to find laser pointers that take AA batteries, these days. Those little button-cell pointers are churned out by the zillion, and many pen-shaped pointers use a couple of AAAs - but if you want the substantially higher capacity-per-dollar of AA power, I think you may have to assemble your own pointer. Or, at least, hack bigger batteries onto a smaller pointer.)

The key component in a do-it-yourself laser pointer is a laser diode, lens and heat-sink assembly - commonly referred to as a laser “module”, or “package”.

Well, that’s the key component unless your DIY ethic requires you to build the module from scratch, as well.

(The state of the DIY art has not, to my knowledge, yet reached actual home-made laser diodes. It’s surprisingly easy to make your own very dim LED, though!)

There’s no financial reason to build your own laser module, because you can buy ready-built modules in various shapes and sizes - even in colours other than red - startlingly inexpensively on eBay, or from dealers like DealExtreme. And no, Australian Customs won’t confiscate your laser module, either - or, at least, they didn’t confiscate any of mine.

Because, like an IR thermometer, a laser module is demonstrably not a laser pointer. And it is laser pointers that are illegal here, don’t you know.

(I haven’t tried importing a genuinely dangerous high-powered laser module, of the type used in hefty laser “pointers” that were already illegal in Australia before the current ridiculous laws went through. I would make a small wager that you would have no trouble importing such a module at all, though. But don’t worry - as we all know, those scary domestic terrorists who we keep being warned about, but who mysteriously never seem to actually commit any acts of terrorism, must be so impotent on account of how they are too dumb to figure out how to connect a multi-watt invisible-beam IR laser module - you know, a laser that’s actually dangerous - to a battery.

Ahem.

The question for the non-terroristic cat-toy maker is which of the (very) numerous cheap red laser modules will actually suit your purpose. I am happy to announce that I’ve done the legwork for you, here, for DealExtreme’s range at least. I bought a few of their finest, cheapest red laser modules, and this one, yours for a princely four US dollars and six cents delivered to anywhere in the world, is the one you want.

It’s got a nice big sturdy heat-sinking case, it’s usefully, though not dangerously, bright from modest power, and it’s got the abovementioned adjustable collimating lens, too.

The other components of a DIY laser pointer:

1: Batteries. Two AA alkalines, in this case; feel free to use some other combination if you like. (Three D cells would give you outrageously long run time.)

The batteries you choose determine which…

2: …resistor you should use in series with the laser module.

Laser diodes, like their older relatives, the LEDs, need some kind of current limiting to prevent them from going into thermal runaway and dying very quickly. Inline resistors are usually the simplest option.

I found that the four-dollar DealExtreme module ran nicely, but not excessively, brightly from two AAs through three 91-ohm resistors in parallel, for an aggregate 30.3 ohms. I couldn’t find a roughly-30-ohm resistor for the final assembly, so I used a couple of 16s in series. Small laser diodes draw only tens of milliamps, so little quarter-watt resistors are more than good enough.

If you buy some other laser module, don’t just trust the “2-4.5V” or whatever that was listed on the eBay auction, hook it up to two AAs, and kill it. You’ll need to put a multimeter in milliamps mode - which, remember, has a little resistance of its own - in series with the module and fiddle with batteries and, initially, larger resistance values, to find a suitable value. (That’s how I ended up with three 91s in parallel - I started with one 91-ohm, which gave a very dim beam, then put another one in parallel, et cetera.)

The quick and dirty way to figure this stuff out for a laser module of unknown provenance is by starting with resistor values that’re clearly much too high - by themselves, across the power supply, they’ll let much less than the module’s rated current flow - or by using a bench power supply that lets you limit voltage and current. Then you reduce the resistor value (or gingerly wind up the current knob) until the dot stops getting noticeably brighter. Wind it back a bit from that point and you should have a safe value. Or just stop when the dot’s still getting brighter with more current, if it’s already bright enough for your purpose.

Or you can, of course, sidestep all of this and just buy that DX module, and run it from two series 1.5-volt cells and about 30 ohms.

3: A battery holder. Little black plastic holders like the one I used are almost free on eBay, or you can bodge something up yourself. (Thumb-tacks make good battery contacts, by the way.)

4: A switch. I used a microswitch I had sitting around, which gives a pleasing tactile feel. Any old switch will do, though. Momentary, like my microswitch, if you want the usual hold-down-the-button kind of laser pointer, or standard “unbiased” if you want a pointer that stays on by itself.

(For about the same almost-free price as a black plastic AA-battery holders, you can get a black plastic AA-battery holder with an unbiased switch built in.)

5: Stuff to hold it all together. Solder and glue, for a more professional result; tape and positive thoughts, for a less professional one.

The weird organic-looking white stuff on my pointer is a couple of blobs of polycaprolactone plastic, about which I must digress, because it’s brilliant stuff.

At room temperature, polycaprolactone is a tough white plastic, like nylon. But above about 60°C it becomes a pliable, bouncy, transparent putty-like material.

(This is the laser assembly before the second blob of polycaprolactone had fully cooled. It’d be fun if it stayed like that, but you can’t have everything.)

You take polycaprolactone granules, and you put them in boiling water, and they turn clear and stick to each other. Just stirring the growing blob around a bit will pick up any loose pellets. Then you fish the spongy blob out and squeeze the hot water out (a slightly painful procedure), and then form the blob to suit your task, usually by just sticking it onto something and squeezing it into shape. Hot polycaprolactone sticks well to all sorts of surfaces, but not so well that you can’t peel it off if you make a mistake. And you won’t get scalded while doing this, because unlike water, the plastic is lousy at transferring heat to your fingers.

(If you heat polycaprolactone above 100°C, by, for instance, microwaving it instead of putting it in water, it apparently becomes a lot stickier, as well as much more able to burn you. So you might want to leave those higher temperatures to the rapid fabricators. I needed to smooth a little bit of my polycaprolactone blobs, so I wafted a small butane flame past the plastic. But then I smoothed it over with a damp screwdriver, instead of my finger.)

As polycaprolactone cools, it clouds up and stiffens, but does not appreciably shrink. If you haven’t gotten your new plastic part shaped right before this happens, just pop it back in the water to re-soften. It’s easier to re-shape polycaprolactone than it is to shape it in the first place, because there’s less water to squeeze out. You can re-heat the plastic as many times as you like, too, and any excess can go back in the bag for later.

Polycaprolactone in the molecular weights that make it behave in this useful way is manufactured in vast quantities by at least two companies, Solvay and Dow Chemical. Which is great to know if you need a ton of the stuff, but not so much if you just want to replace a missing knob on a radio. (That was my first polycaprolactone project. It worked beautifully.)

Other companies repackage polycaprolactone in smaller quantities at large markups. “Polymorph“, “ShapeLock” and “Friendly Plastic” are all polycaprolactone. The first two are very much the same; Friendly Plastic comes in a white-pellets version too, but is also available in a wide range of more-expensive coloured versions. You can colour polycaprolactone yourself, but if you need even, repeatable hues and/or metallic effects, and you don’t need a huge amount of the stuff, then you’d probably do better just buying Friendly Plastic.

(The bone-white version is of course preferable, if you want to make creepy biomechanical thingummies.)

If you’re in Australia and you just want to see what polycaprolactone is like, get yourself a hundred grams of “Polymorph” from Jaycar for $AU11.50. (Plus delivery, if you buy it online rather than over the counter.) That may go a surprisingly long way; I didn’t weigh the Polymorph that went into my laser pointer, but judging by volume it was probably no more than 25 grams.

If you’re in the States, there are lots of retail polycaprolactone sources. Try the Maker Shed.

If you’re outside the States and want a larger, but not vast, amount of the stuff, many companies stand ready to rip you off.

You can place an international order at Shapelock.com and pay for it, with a pleasingly low shipping fee - and then they’ll refund your money, because they don’t actually ship overseas. And then they’ll tell you to order from Jameco instead. Jameco’s international shipping fees aren’t mentioned on their site; you can place an order and give your payment info and wait for the delightful surprise, or you can e-mail them, whereupon they will inform you that their cheapest price to send a $US24.95 half-kilo of Shapelock to Australia is $US39.

Sorry. Just had to get that out of my system.

OK, here’s how people outside the States - and possibly inside, actually, depending on how all the prices shake out - can buy polycaprolactone at a non-stupid price. Go to this eBay dealer in the UK (on ebay.com, on ebay.co.uk), who’s currently on holiday until the 8th and has invisibilised their auctions, but will actually still let you place an order via this listing. They’ll sell you 500 grams of Polymorph-branded polycaprolactone for £9.50 plus quite reasonable delivery, with a microscopic discount for multiple half-kilos.

[UPDATE: As pointed out in the comments below, that eBay dealer has a separate Web site too, from which you can download a great PDF about what you can do with Polymorph.]

To make sure I get my order in before all of y’all, I just ordered a key, man, for a total of £32.75 delivered to Australia. That’s about $AU54.20, or $US49.80, as I write this.

A kilogram of polycaprolactone is quite a lot - especially when you consider the near-infinite reuseability of the stuff. Unless I suddenly start building sizeable structures, I don’t anticipate having to buy any more for some years.

Jaycar offer discounts for bulk purchase, but a kilogram of Polymorph from them is still $AU89.50 ex delivery. So the eBayer in the UK looks like a good deal.

Hm. This post started out being about making a laser, and ended up about making freeform plastic bones. Eh - it’ll do.

Do feel free to discuss either subject in the comments!

I originally thought this blue-eyed cockatoo was, in another triumph of creative bird naming, called a Blue-eyed Cockatoo, but as commenters below point out, it’s actually a Little Corella.

It showed up all by itself at the feeding table, and grumpily snapped at the sulphur-crested cockatoos when they tried to get some of the seed. The newcomer is significantly smaller than a sulphur-crested, with a much less impressive crest, but it’s bigger - and apparently more bad-tempered - than a galah.

The newcomer was very successful at keeping the usually-boisterous mob of bigger birds away for a few minutes, while it filled up on the mound of sunflower seeds. (I am, as regular readers know, engaged in an ongoing experiment to determine whether wild cockatoos can become obese.) Then it flew away.

It took me a few tries to identify this bird [and then, as I’ve mentioned, I got it wrong…], because I couldn’t find anything resembling it in Birds in Backyards‘ excellent Bird Finder. The Finder usually leads you quite easily to the right Australian bird - it’s my first stop whenever I see a new feathered beastie here in Katoomba. But it didn’t work this time.

I thought that meant this wasn’t an Australian bird; if it actually had been a Blue-eyed Cockatoo, it would have been a slightly endangered native of the Bismarck Archipelago of New Guinea. That’s about 3100 kilometres (1926 miles, 558 leagues, 15,410 furlongs) from this house. As the crow, or cockatoo, flies.

So I figured this one was probably an escaped pet. But since it’s actually a Little Corella - the bags under the eyes are quite distinctive, if the crest isn’t up - the only odd thing is that I’ve never seen one at the feeder before. I don’t know why I didn’t find this bird’s page on Birds In Backyards. Perhaps someone forgot to tick the “blue” box in the “colours” part of that database entry, or perhaps I insisted it was finch-shaped, or something.

If you like watching large decorative birds eating seed, flapping around and squabbling with each other, this is the blog post for you.

As regular readers know, I shovel ever-increasing quantities of seed down the throats of whatever birds deign to visit the table on our deck. Most of the freeloaders that show up are Sulphur-crested Cockatoos (they even outnumber the pigeons!), and I’ve shot video of them before. But it only now occured to me that I could clamp the camera onto the table and go away.

So that’s what I did.

This is before the full afternoon mob showed up, so it’s relatively civilised.

Same table, most of the same cockatoos, a little further away.

And now, the afternoon rush!

It gets a bit samey toward the end, there, but I laughed every time another huge beak filled the screen, so I let it roll.

(I swear one of ‘em tries to say “cock a doodle doo” at 5:44.)

I just put out some more bird seed, because I noticed that this morning’s supply had been depleted by the usual mob of colourful creatures, but also because one of the birds still picking at the few seeds left clearly needs all the help it can get.

It’s a cockatoo with a fairly advanced case of “psittacine beak and feather disease“. I could have taken a picture of it, but it always makes me so sad to even look at a cockatoo with this disease that I just couldn’t stand it.

It also makes me sort of aimlessly angry, wishing God existed so I could ask Him what the bloody hell He thought He was playing at.

Psittacine beak and feather disease is, in brief, a virus which takes one of the most beautiful creatures in the world, and makes it uglier and uglier until it is so ugly that it can no longer eat, whereupon it dies. If opportunistic infections of the bird’s devastated feathers and tumorous, necrotic beak and claws haven’t killed it already, that is.

There is no cure, or even specific treatment, for psittacine beak and feather disease.

There are hundreds of diseases of humans and animals that’re just as horrible. But few are as purely and plainly awful as this one. It’s like a metaphor for the unfairness of life.

Right - I’m off to Cute Overload for a while.

We have not yet completed the full successive approximation needed to accurately measure Charley’s volume, and this irregularly-shaped tub may or may not allow for more precise computation.

He sat in there perfectly happily for some time, though.

Yep, that’s a cat on an air conditioner all right.

Right up next to the ceiling.

Joey’s not just the Amazing Fetching Cat, he’s also the Amazing Exploring Cat. A preposition isn’t just anything a rabbit can do to a hill; it’s anything Joey can do to a cardboard box, curtain rail, wardrobe…

Twice, now, Joey’s managed to end up stuck at the bottom of the square vertical well created by two bookcases I’ve screwed together for stability in a corner. I’ve stuffed a cushion in the top of the hole now, to reduce the chance that I’ll have to shift furniture to rescue a small miaowing thing again.

(It usually seems to take him a few hours to start miaowing. If Joey finds himself stuck somewhere, he usually just goes to sleep for a while.)

[UPDATE: As of September 2009, he’s done this three times. He got past the cushion.]

My office air conditioner was a new Joey-perch, though. He’d gotten there from the curtain rail.

(I’ll say one thing for adventurous cats: They do a great job of removing cobwebs from hard-to-dust places.)

Despite the slipperiness and downward curve of the top of the unit, he seemed quite happy there for a little while. But then he wanted to get back down.

So far, so good…

“Hang on a minute lads, I’ve got a great idea!”

This little bookshelf speaker is suspended from an ordinary picture-hook.

I’m glad I stuck rubber feet on the back of the speaker to stop it wobbling.

The speaker turned out to be of limited interest.

I’d been helpfully tapping the top of the printer to alert Joey to its usefulness as a landing pad. He looked, he thought about it… and then he decided to just hurl himself onto my shoulder, for a 100% successful claw-arrestor-hook landing.

You might think that’d be painful, but I’m pretty much numb, these days.

I’d completely forgotten about this.

Anne (un-updated blog here; note the post from when we got Joey) shot this video less than two months before Mickey died, with the intention that I could put it on a loop on my second monitor, as a sort of relaxing furry mental wallpaper.

I didn’t, at the time, think it entirely necessary to subject my blog readers to five straight minutes of Mickey and Joey sitting in a box licking each other, even if it was in their usual could-turn-into-a-wrestling-match-at-any-moment way.

But now that Mickey’s gone, I feel the self-indulgence is justified.

(Joey appears to be quite ready to bond with the new cats in exactly this way, but they’re still growling at him. They’re becoming more mellow every day, though.)

Update:

The aftermath.

Clearly, this box was not large enough to effectively measure the volume of two cats.

(See also.)

Nothing helps you get over the death of a pet like getting a new one. So right after we buried Mickey, we found ourselves a new cat in need of a home.

I know this looks like two cats, but they’re so closely connected that they probably actually qualify as one. Tentative names: Charley and Susie.

The little soft house technically belongs to Joey, but he doesn’t seem to be missing it. He’s engaged in some perfunctory dominance behaviours in the direction of the new ginger twins, but I imagine he’ll be using them as a heated mattress…

…just as he used Mickey, soon enough.

Mickey the cat - the subject of the famous kitten review - is dead. He was about five and a half.

I found him like this. He looks as if he’s just asleep - only the little bit of purple tongue sticking out gives it away.

He was stone cold and stiff as a board, though. So I dug a hole in the garden and put him in it. Then we sprinkled some flower seeds on top and watered them in.

This isn’t the way it’s meant to happen. Mickey was a big strong healthy boy. Really big; he was quite lean, but very long and tall, for a cat. He weighed seven and a half kilos just a couple of weeks ago.

Perhaps that was it; perhaps he didn’t have a strong enough heart for a body that size. I’m at a loss as to what else it could have been. Cats that know they’re sick hide themselves away somewhere, but Mickey just curled up on the spare bed as normal. And there was no vomit, no signs of distress; I don’t think he’d even been off his food, though I might not have noticed.

Perhaps the last time he went out, for only about ten minutes before he decided it was too cold and came back in, he ate a poisonous mushroom along with some grass. Those are famous for killing people half a day after they eat them. Or perhaps he picked up a tick, though it’s freezing cold here in Katoomba right now, so there shouldn’t be any ticks around. I don’t think it was rat poison or slug bait or something like that. But who knows.

When you own a pet, you expect - or should expect - that at some point you’ll have to pay quite a lot of money to buy that pet several, or at least a few, more years of happy life. Look at Tom, with his arthritis and diabetes and a bout of hyperthyrodism, too. It cost a bloody fortune to get him repaired, and he still needs injecting twice a day. But Tom’s happy as a clam, settling peacefully into the prolonged geriatric period that’s normal for elderly housecats.

Mickey, on the other hand, was the picture of health, as far as I could see. But he was there last night, and gone this morning.

He was a very good boy.

A couple of irretrievably soft-hearted readers have asked if there’s any particular animal charity to which I’d like donations to be made in memory of Mickey.

Mickey came from one of the Cat Protection Society “aquariums” full of kittens that you can see in the window in some Australian vets.

(Yes, they do let the kittens out regularly to run about. But it’s amazing how many of them will be perfectly happy in a thousand-litre Perspex box for hours on end - though at least one bright spark does always seem to end up sleeping in the litter tray.)

The Cat Protection Society would, of course, be very pleased to receive your tax-deductible donation or volunteer time. And then there’s the RSPCA in Australia, the UK and elsewhere in the Commonwealth, and their equivalents the ASPCA in the States.

These sorts of organisations always run shops. The “op shop” type with low-priced used stuff can be fun but, given the prices, can’t actually add much money to the bottom line of the charity. I highly recommend you patronise the other kind of shop, like the RSPCA Shops here in Australia. Those shops sell the usual sorts of “pet shop” animal supplies - toys, food, tennis ball chuckers, noisome dried pieces of pig or bull (not, for very good reason, cow…) of which dogs cannot get enough - at the usual rip-off pet-shop prices. You can get all of these things much cheaper if you shop more carefully - but the profit from the charity-shop rip-off pricing all goes to the charity, so when I’m there, I specifically seek out products which seem to be the worst value.

If you can’t afford to donate, buy overpriced catnip mousies or spend a lot of time having your heart rended by the predicament of abandoned animals, but you live near an animal shelter or veterinarian that has a Room Full O’ Kittens, be advised that they may be very happy to have you just visit and play with the kittens for an hour, provided you don’t seem too likely to eat any of them.

Kittens need to get used to being picked up and patted and played with, and veterinary and animal-shelter staff are likely to be pretty busy. So the terrible responsibility of being covered with kittens for an hour a week may, I fear, fall to you.

Tom’s Web page will be ten years old this year, and Tom himself is fifteen.

He’s still quite chirpy. Only about 6.5 kilograms, versus almost ten in his prime, as depicted in the famous kitten review. But that’s just as well, since Tom’s had arthritis and diabetes for a while now.

Neither complaint actually seems to have bothered him much. He’s always considered movement to be highly overrated.

Tom has a great enthusiasm for the tuft of lemongrass in my mother’s back yard. He’s never really figured out how to eat it without help, and all he ever does after eating it is throw up - sometimes practically immediately. But he seems to enjoy the whole experience enormously.