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  • PKM commented on PKM's instructable Dining Chair From a 2x4
    Dining Chair From a 2x4

    Thanks! I use Sketchup, because it's very quick for doing simple design like this. I changed the rendering style slightly so it draws the edge lines a bit heavier which makes for better screenshots.

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  • PKM commented on Jule's instructable Electric Bike - the HARD Way
    Electric Bike  - the HARD Way

    It's not finished yet but I'm blogging about it as I go at http://cuttheredwire.uk/blog/ebike

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  • PKM commented on Jule's instructable Electric Bike - the HARD Way
    Electric Bike  - the HARD Way

    Yikes - this is already "the hard way" and I'm trying to do the thing you decided aginst, fit everything in the frame above the pedals!I scratched my head for a long time about how best to mount my sprocket to the wheel and eventually made a single adaptor plate which I zip tied to the spokes. Your idea about making it in two parts which can sandwich the spokes is a good one, maybe I'll try something similar when mine inevitably breaks :)

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  • PKM commented on wouterH10's instructable Oled Alarm Clock
    Oled Alarm Clock

    I love this! I'm a fan of dimmable diffuse LED light, and sunrise/wake-up lights, and using the OLEDs for clock displays is a nice added touch. Many moons ago someone sent me a RTC module and some warm white LEDs to make something like this and it's really time I actually finished it

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  • PKM commented on joe-pioneer's instructable The Eratosthenes-inator
    The Eratosthenes-inator

    This one specific observation (the angle of the sun relative to two points at the same time) does, as you point out, have multiple possible solutions. This one single observation is not sufficient to prove conclusively that the earth is in fact a sphere (as someone else pointed out, it could for instance be a cylinder).That's why we combine the observations made at many points on the globe at different times, all of which combine to demonstrate beyond reasonable doubt that the earth is in fact a sphere. This experiment can be conducted with any pair of points in the world and the results will be consistent; ships disappear below the horizon in all directions; the heavens rotate about a point in the sky with an elevation equal to your latitude; different latitudes have different climates…

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    This one specific observation (the angle of the sun relative to two points at the same time) does, as you point out, have multiple possible solutions. This one single observation is not sufficient to prove conclusively that the earth is in fact a sphere (as someone else pointed out, it could for instance be a cylinder).That's why we combine the observations made at many points on the globe at different times, all of which combine to demonstrate beyond reasonable doubt that the earth is in fact a sphere. This experiment can be conducted with any pair of points in the world and the results will be consistent; ships disappear below the horizon in all directions; the heavens rotate about a point in the sky with an elevation equal to your latitude; different latitudes have different climates and the seasons change in ways consistent with a spherical earth; every other planet in the solar system is a sphere, because a mass of rock thousands of miles across couldn't remain in a stable non-spherical* shape because of gravity, and so on.* yes slightly oblate spheroidal if we're being pedantic

    I mean... that's patently not true. Any "evidence" which I've ever seen claimed for a flat earth has glaring scientific flaws visible to anyone with reasonably science literacy or rely on misunderstandings of simple principles. Every observation in astronomy, including very simple ones anyone can do like watching the stars rotate at night indicates a spherical earth, as does any map of "where is it daylight now", as does the fact that you can fly from South Africa to Australia, and every photo of the earth taken from space, and in fact every map not sold at a flat earth conference. The "evidence" I see held up for a flat earth is things like claiming the moon emits cold laser light which lowers in temperature the more you concentrate it, questioning whether…

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    I mean... that's patently not true. Any "evidence" which I've ever seen claimed for a flat earth has glaring scientific flaws visible to anyone with reasonably science literacy or rely on misunderstandings of simple principles. Every observation in astronomy, including very simple ones anyone can do like watching the stars rotate at night indicates a spherical earth, as does any map of "where is it daylight now", as does the fact that you can fly from South Africa to Australia, and every photo of the earth taken from space, and in fact every map not sold at a flat earth conference. The "evidence" I see held up for a flat earth is things like claiming the moon emits cold laser light which lowers in temperature the more you concentrate it, questioning whether the force of gravity actually exists (easily demonstrated with simple lab equipment) and so on.

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  • Easy Veggie Bowl Meal Prep - Vegan

    "It's a main dish, not a side dish" https://www.youtube.com/watch?v=ZdLhjeKey7kI like the look of this approach - I'm trying to meal prep good veggie food for lunches, this looks like it could broaden the repertoire beyond lentil chilli and chickpea curry.

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  • I've been playing with this recently trying to make ink for handwriting. I believe in your case the actual pigment is formed when dissolved iron reacts with tannins in the wood to make ferrotannate; I'm using strong black tea as my source of tannins and mixing it with the iron solution. You can see the reaction happening here: https://twitter.com/PKM_ibles/status/1138379992491053056I left a piece of steel wool scrubber (coarser than your wool so less surface area) in vinegar for 48 hours and almost none dissolved - then I added a teaspoon of salt and a teaspoon of hydrogen peroxide and it dissolved a lot in three hours. If you want to speed up the process, you might try that. I have a suspicion the peroxide can also help change the colour, because if you let it oxidise longer you get l…

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    I've been playing with this recently trying to make ink for handwriting. I believe in your case the actual pigment is formed when dissolved iron reacts with tannins in the wood to make ferrotannate; I'm using strong black tea as my source of tannins and mixing it with the iron solution. You can see the reaction happening here: https://twitter.com/PKM_ibles/status/1138379992491053056I left a piece of steel wool scrubber (coarser than your wool so less surface area) in vinegar for 48 hours and almost none dissolved - then I added a teaspoon of salt and a teaspoon of hydrogen peroxide and it dissolved a lot in three hours. If you want to speed up the process, you might try that. I have a suspicion the peroxide can also help change the colour, because if you let it oxidise longer you get less blue-black ferrotannate and more brown iron hydroxides - food for thought?

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  • PKM commented on thexadow's instructable Shoji Lamp (3D Printed)

    Dang, your shoji lamps look better than my shoji lamps ._. The next one I build will definitely take some inspiration from your examples at the top.

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  • Mmm, pecan frosting... this looks seriously good! I'm curious - is there something in the recipe or the way it's made that makes this a Texas sheet cake specifically? Or is that just a general name for big iced flat cakes?

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  • Making the bit by your fingers blunt means it looks like you've lost a lot of potential machete blade. Would it be wrong to have a symmetrical handle (like a mallet), and the opposite side of the blade sharp? That way no slicing your finger in axe mode, longer machete blade, and if the "top" of the axe is sharp but the bottom blunt you can use it as a Froe. You could call it "Tou and froe" :)

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  • That's a nice looking hammer! I love the story behind this, and I think there was a very valuable tip in your introduction: if there's something you get stuck working on, put it away for later, leaving a note with the key points on it. I've put away plenty of Arduino projects which I've then lost the code for and when I come back to it, I can't make it work.Having a note saying "I've stopped working on this because I don't have an X"... maybe years later, you'll find it and you've got a junk box full of X which your past self needed.

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  • I love it! This could be just the thing that finally lets me squeeze some actual workbench space into my 5x7 foot shed. I'd probably put shelves or storage box rails underneath and live without the vacuum (or get a battery powered mini vac to cut down on space used and just empty it more often).

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  • PKM commented on randofo's instructable IPhone Camera Spinner

    So, if you can arrange it to turn the camera end-over-end at the right speed (which I did with a GoPro by crashing my quadcopter into the ground), the rolling shutter will make it take a nice 360 panorama as it rolls from sky to ground to sky again. Having only achieved it by blind luck I'm not sure how easy it is to synchronise with frame rate though...

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  • PKM commented on SimonRob's instructable The Earth Clock

    Take that, flat earthers ;)

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  • These look great, I love the look of the mixed purple beads one in the last image.This could be part of a great small batch manufacture process: build/carve/CNC/3D print a part, make a negative mould with pourable silicone, cast a bunch of pieces. That way you aren't limited by what you can find ice cube trays for :)

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  • PKM commented on Sejma's instructable Some Cool Batch Applications

    -f means force shutdown without asking to close running applications. See more switches and their meanings at https://www.computerhope.com/shutdown.htm

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  • PKM commented on bricobart's instructable Hole Saw Adze

    So is that metal stud in the last pictures just there to make it look like a horsey? Because it looks like a horsey.

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  • PKM commented on Creativity Buzz's instructable MINI LAPTOP

    Well, I trust this more than the "how to make a DIY mains powered glue gun" video William Osman warned us about :) though it does use the same music which is a little unsettling. Maybe the battery powered screen isn't bright enough to show up well on video, maybe the one they made had some other issue like a broken ribbon cable and editing in a screencap was easier than fixing it, maybe the raspberry pi is too slow to make good video and they went with the smartphone advert "sequences shortened" approach :) whatever the cause, I'm relatively confident something like this could work even if it needs a couple of tweaks to perform properly.

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  • Because we use stacking software to align all the photos together so you only ever see 10 seconds worth of star movement. 50 x 10s exposures comes out looking the same as a 500 second exposure where you re-oriented the camera to the apparent movement of the sky every 10 seconds. (This is the alternative approach: make a motorised mount which tracks the sky and then just stack all of your exposures directly on top of each other).

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  • 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 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 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 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 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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  • 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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  • 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 PKM's instructable 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 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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  • 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?

    I think the outside diameter of those pieces is 7mm

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  • 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 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:
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  • PKM commented on rschoenm's instructable 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 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 Armor

    You and this guy need to meet up :)

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  • 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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  • PKM commented on fs woodworking's instructable 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 jessyratfink's instructable 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://healthyeati…

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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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  • "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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  • PKM commented on ModMischief's instructable 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 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 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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  • 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 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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  • 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 Lamp

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

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