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25Instructables2,181,338Views2,788CommentsCambridge (UK),IRC@PKMJoined June 23rd, 2006

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  • PKM commented on bricobart's instructable 'Shave Mouse' Aka Revisited Shave Horse 2 months ago
    'Shave Mouse' Aka Revisited Shave Horse

    Bart's back!Hold on while I put goesting in my lexicon of words that will let me think about my situation better. So typical of the English, hygge (drinking hot chocolate in bed while wearing a woolly jumper) goes viral but we haven't caught on to a word that means "passion".Here's hoping the north Atlantic stays less windy for your crossing than it has been recently. I blame El Nino.

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  • PKM commented on lingib's instructable CNC Pen and Wash Portrait3 months ago
    CNC Pen and Wash Portrait

    Seriously... this is embarrassing. I've been planning (plotting? har har) to build one of these for years, I just recently got my hands on a traditional X-Y plotter and started drawing things with it, and felt pretty pleased with myself that I'd generated a drawing with hatched shading so it could draw more than just linework. Then I see your instructables and you've done all the same stuff but to better quality and written an Instructable about it. I'll get back in my box...

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  • PKM commented on Alex in NZ's instructable Fence Stake Driver3 months ago
    Fence Stake Driver

    It's called lean manufacturing :)When I was building this I went around the shop looking for food that came in the right size of can and that's what I had for dinner that day...

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  • PKM commented on lingib's instructable CNC Pen Lift3 months ago
    CNC Pen Lift

    Did you publish this after seeing the analytics of me searching for about a hundred variations of "servo pen lift" last week looking for inspiration on how to build my own? Using tool clips is a great idea, probably more convenient than my "V blocks with elastic band superglued over them" holders.

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  • PKM commented on Donald Bell's instructable Too $hort Cat3 months ago
    Too $hort Cat

    Also for hilariously awful borderline self-parody hip hop, may I suggest Slim Jesus's magnum opus "Drill Time"?

    "Something about this cat’s salacious gyrations spoke to me"There's a sentence I never expected to read. My headphones are broken so I can't really hear the music that well but I get the gist, and it's fantastic.

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  • Folding Workshop Workbench! 折疊式工作臺!

    My shed definitely needs one of these. The only problem is I need another shed to put all the stuff from the first shed into when I'm using the workbench. Then that shed will need a folding workbench as well, which means ...

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  • Make Mini Drone (Simple and Cheap)....!

    So on the existing helicopter (looks like a Syma S107 or clone) there are two counter-rotating blades for lift and rotation, and a separate vertical tail rotor for tilting forward/backwards. How do these controls let you tilt the drone forwards/backwards and left/right if the two pairs of motors are connected to the helicopter's two main motor connections?

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  • PKM commented on AMAL MATHEW's instructable Quad Copter From Scratch4 months ago
    Quad Copter From Scratch

    Those motors look a lot heavier than most of the brushed motors I've seen on quadcopters- I just bought a Syma X5C and the motors are 7mm diameter, barely thicker than a ballpoint pen. Your motors are a lot bigger so will probably need much more lift, which will mean bigger props.The bigger problem here will be control: how do you propose to vary the speed of the motors when it's flying?You should definitely keep at it, you might well get this model flying while tethered to the ground - or alternatively, build a fixed wing plane and attach a long string to one wingtip so you can fly tethered outside. Once you've done that you can move on to adding R/C features and maybe have yourself something controllable :)

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  • PKM commented on PKM's instructable Simple Arduino Sunrise Lamp5 months ago
    Simple Arduino Sunrise Lamp

    Hi Inga,I measured the LEDs drawing 650mA at 5V, which means the power was 5*0.65 = 3.25W. You could use whatever wattage of LEDs you wanted as long as your transistors are capable of switching enough current. Small electronics transistors like the 2N222A can only switch about half an amp so if you want more than a couple of watts you'd be better off finding some bigger power transistors or a dedicated LED driver device.I used an old Arduino Duemilanove, you could use whichever type you want as this project only needs one digital output pin. The code should work on any Arduino (but you might have to change pulsepin if yours doesn't have a pin 11).

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  • PKM commented on brichtl's instructable Transfer Images to Fabric5 months ago
    Transfer Images to Fabric

    The oil you are using is this one https://artnaturals.com/artnaturals-lavender-oil-heals-burns-cuts-stings-and-bites-4-fl-oz-118-ml-15-00.html ? I was going to ask if it had any alcohol or other solvents in it but it doesn't look like it does from their description. I'd guess lavender oil is a stronger solvent than the usual edible oils. Perhaps you could make it work with a little rubbing alcohol or similar solvent in a different oil.

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  • PKM commented on KarelK16's instructable Converting a Dollar-motor to Lego7 months ago
    Converting a Dollar-motor to Lego

    I think the outside diameter of those pieces is 7mm

    Just a thought- could you drill out the gear large enough to accept an axle connector like this one, so you could use whatever length of axle you wanted, or have it only protrude out of one side of the motor?

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  • PKM commented on sdobbie's instructable Storing Files on an Audio Cassette7 months ago
    Storing Files on an Audio Cassette

    If the second trace is what you got back from the tape recording, your output level when recording is too loud. The signal is clipped (https://en.wikipedia.org/wiki/Clipping_(audio)) which means it's distorting and losing information. Great for electric guitar music, not so great for data storage.If you try it again, turn down the sound volume on your computer when you record the data to the tape. I'd do this with the output slider in Audacity- put the volume to 50%, let it play for a minute, turn down the volume to 40%, another minute, then 30% etc. You'll then be able to look at what recorded on the tape when you play it back and find the right volume where the audio waveform isn't distorted but is still loud enough.

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  • PKM commented on dpeach's instructable LED Trunk Light Upgrade8 months ago
    LED Trunk Light Upgrade

    Ah! I was meaning to do this to my car over winter and I was intending to splice the LEDs in parallel with the bulb so both worked at the same time, but was put off by the idea of modifying the wiring. Using the festoon bulb holder to mount spade connectors is a great idea and completely reversable if you want to sell the car, maybe I'll revisit it

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  • PKM's instructable Simple Arduino Camera Trigger's weekly stats: 9 months ago
    • Simple Arduino Camera Trigger
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  • PKM commented on rschoenm's instructable Nested Helix1 year ago
    Nested Helix

    Because the first one is so pale, I saw the thumbnail and thought "huh, that's a neat 3D printing demo". Then I read the article and went "Holy ****, they are made of wood? How on earth..."

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  • PKM commented on MRHoffman's instructable DIY Chicken Wire Ghosts1 year ago
    DIY Chicken Wire Ghosts

    I love it! Genuinely unsettling halloween decorations are my favourite, way better than smiling cartoony pumpkins and vampires (if you don't have to worry about terrifying small children).One tip: if you don't have glow in the dark paint but you're going to use a blacklight, highlighter ink glows strongly under UV light so you could use that instead. You can take the felt ink reservoir out of a highlighter pen and soak it in water to make your own glow fluid- see 3 Ways To Make Water Glow. This way you can even get different colours, though it won't be as bright as glow in the dark paint.

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  • PKM commented on MWiggs's instructable Starcraft 2 Jim Raynor Armor1 year ago
    Starcraft 2 Jim Raynor Armor

    You and this guy need to meet up :)

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  • Flawless geometric designs made with tape

    I guess this doesn't even have to be done with glaze on pots - you could use the same technique to apply, say, fabric paint to a plain cylindrical lampshade? As long as what you are using for the design doesn't dissolve the tape or bleed under it, it should be good.

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  • If it were me, the primary use would be like a "helping hands" for soldering or other detail work, under manual control rather than automated movement. A robot arm big, strong and precise enough for any bigger jobs would probably be unaffordable in terms of materials.What would really make it stand out from both manual helping-handses and MeArm-type projects would be good IK so you can move the end effector in XYZ coordinates, rather than just controlling the joint axes directly.What's the background of your team of engineers?

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  • The first link should be https://www.instructables.com/id/Dead-Bug-Prototyping-and-Freeform-Electronics/step7/Little-Wire-dead-bug-art/

    If you're good at soldering (and you'll have to be to make any circuit that small), you can dead-bug solder an 8-pin ATTiny chip and the passives you need in that much space. Then it can fade in, fade out, blink "Happy birthday" in Morse or flicker like a candle- it's just a case of programming it to do what you need. You wouldn't need that many components, you could reproduce this circuit (I think the linked one is to make the chip programmable in-circuit which you probably don't need)If you need to do it with only discrete components, you can use something like this circuit but it might be more challenging to solder because there are a lot of links to make.

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  • Suggestion: Get a 12v cooler, leave it in your trunk filled with water bottles and reusable ice packs. They draw about 50W or 3.5A@12V so you could continue running it for an hour or so without worrying too much about flattening your battery, although having a second battery would be a real bonus. You can get batteries with higher capacity than a normal car battery if it doesn't have to be able to provide hundreds of amps to crank your engine and it doesn't matter if it goes flat. When necessary, pull a cold water/coke/ice pack out of the cooler- it's much more efficient to just cool yourself rather than try to cool the entire inside of your car.

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  • PKM commented on fs woodworking's instructable The Wooden Light Bulbs1 year ago
    The Wooden Light Bulbs

    Clever! I have some leftover LED strip, might have to make one of these into a table lamp...

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  • PKM commented on JXZ's forum topic Tiny Programable board for 2 LEDs?1 year ago

    The Digispark may be what you need. It's Arduino compatible, so there will be a ton of tutorials on how to write simple code that blinks LEDs. It's cheap ($8), about an inch square, and simple to assemble as long as you can solder a few through-hole components or know someone who can.If space is absolutely vital you could use a naked ATTiny chip, but programming those is a lot more complex than programming an Arduino so maybe isn't suitable for a first project.

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  • PKM commented on jessyratfink's instructable microwave cake1 year ago
    microwave cake

    I made this tonight but it was gone before I had time to take photos! I used Tejana15's suggested metric weights (65g flour, 55g butter) and cooked for 60s in a coffee mug in a 900W microwave, turned out pretty good! Nice springy sponge, the first crumbled a bit on taking it out of the mug because i overcooked slightly, the second had a tiny uncooked bit around the bottom edge where it was in the bottom corner of the mug - maybe don't use heavy walled containers as they suck the heat out while cooking.It smells quite strongly of egg and butter while cooking, but just tastes like sponge cake. I made mini victoria sponges with jam and whipped cream in the middle, the cream definitely helps as the cake was a bit dense in texture.One word of warning: according to this site (http://healthyea...

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    I made this tonight but it was gone before I had time to take photos! I used Tejana15's suggested metric weights (65g flour, 55g butter) and cooked for 60s in a coffee mug in a 900W microwave, turned out pretty good! Nice springy sponge, the first crumbled a bit on taking it out of the mug because i overcooked slightly, the second had a tiny uncooked bit around the bottom edge where it was in the bottom corner of the mug - maybe don't use heavy walled containers as they suck the heat out while cooking.It smells quite strongly of egg and butter while cooking, but just tastes like sponge cake. I made mini victoria sponges with jam and whipped cream in the middle, the cream definitely helps as the cake was a bit dense in texture.One word of warning: according to this site (http://healthyeating.sfgate.com/convert-fat-grams-calories-5127.html) there's over 900 calories in the single recipe (50*9 + 100*4 + egg and milk) before you start adding toppings, so make sure you have someone to share with! The whole thing took about 20 minutes start to finish so they are dangerously easy to make...

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  • The Android camera documentation tells me you can control the aperture (if the device you are using has one), shutter speed and ISO when an app takes a picture. If you wanted to be able to control these things you'd need to write an app which uses those parameters and makes a camera request to take a picture.To use potentiometers you'd need a hardware device that can read those potentiometers - something like the Android Dev Kit:which would communicate those values to the app running on the phone which would then use them to make the camera request.

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  • Grow Ten Tons of Organic Vegetables: Leeks, Onions, Potatoes, Broad Beans, Cabbage, Cauliflower, Sweetcorn, Courgettes & Marrows, Sugar Beet, Beetroot, Carrots, Swede, Kale, Calebrese & Broccoli, Brussel Sprouts & Strawberries

    "North west Wales on an island" - Anglesey?I'd be interested to see how your sugar beet wine/vinegar turns out. Aside from the strawberries, are you growing any fruits or aromatics you might use to flavour the results?

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  • Been a touch busyRenovating my new houseNearly finished nowNew ibles coming'Leccy skateboard in the worksAnd some older stuff

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  • Comments like yours showIt's not always SeptemberOn the internet.Autumn's cold winds blowBright screen under a dark skyThis site warms my heart

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  • PKM commented on tunes4x's forum topic Chevy Flip Car Key Fix1 year ago

    What are the chances- I had this exact problem with my car key the day before yesterday. Did you sort anything out? I'm hoping it's possible to get a replacement for just the fob half and put the blade into the new key, though you'd also have to transplant across the radio and immobiliser for it to work properly.

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  • PKM commented on ModMischief's instructable Vibrator - a Layered Shot1 year ago
    Vibrator - a Layered Shot

    If you want something to do with almond liqueur you have sitting around, layer it with raspberry vodka and irish cream for a bakewell tart shot :)

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  • PKM commented on unusual architect's instructable Dremel Table Saw1 year ago
    Dremel Table Saw

    "I needed to make a small insinuation"I think you might have meant "incision" there- an incision is a small cut, whereas insinuation means hinting or suggesting something. Just a thought.I like the look of this, although the table is quite small- if you made a bigger table this could be a really cool project.

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  • PKM commented on bricobart's instructable Screwdriv'ify your knife1 year ago
    Screwdriv'ify your knife

    What paradise do you live in where hex-head wood screws are common? I went to buy a box of Torx head wood screws because I'm putting in and taking up floorboards so often in my wreck of a house, but the stupid hardware store had virtually none, all the wrong size and they cost something like £8 for 25. 100 Pozidrive screws were half the price, but at what price my sanity having to deal with all those mangled screw heads?

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  • PKM commented on Penolopy Bulnick's instructable Unusual Uses for Mouthwash1 year ago
    Unusual Uses for Mouthwash

    I thought alcohol helped deal with head lice because they breathe through pores in their skin, and the alcohol poisons them. When I was a kid the DIY cure for head lice was methylated spirits on the hair- I wouldn't recommend that, but mouthwash with alcohol in (Listerine is over 25% alcohol!) may well have the same result.

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  • PKM commented on EurekaFactory's instructable How to Fact Check1 year ago
    How to Fact Check

    I had a friend who used to send me all those chain emails witg crazy hoaxes in them- people selling perfume using ether to knock you out and mug you, spider eggs in new bras, that sort of thing. I made it into a game to see if I could disprove it with a reliable source (usually Snopes) while holding my breath. I told her about this game every time I got one of the emails and it must have sunk in eventually because she stopped sending them to me.The point was to demonstrate that checking an unbelievable story online isn't an arduous task, almost always a 30 second google will give you either corroborating sources or a "this is a hoax" writeup.

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  • PKM commented on balsuryana's instructable From Old Motors Into Signal Booster1 year ago
    From Old Motors Into Signal Booster

    I wondered how signal boosters work, so I looked it up on Google. I found http://www.andybrain.com/extras/cellphone-antenna-... which I think tells you everything you need to know (they don't work at all and may make your reception worse).If you don't want to take this one guy's word for it (after his double blind experiment), what about the 184 people who gave this signal booster sticker a 1 star review on Amazon? https://www.amazon.com/Cellular-Innovations--BOOSTER-Universal-Antenna/dp/B00009WCAP/ref=sr_1_5?s=wireless&ie=UTF8&qid=1468241391&sr=1-5&keywords=signal+booster+sticker

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  • PKM commented on Cactus workshop's instructable Vintage Oil Can Lamp1 year ago
    Vintage Oil Can Lamp

    20-W-40 - does that mean 20 to 40 watts? :)

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