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When theres only brute force left

  1. Sep 15, 2010 #1
    What a stressful evening. I figured I wanted to do a pretty complex valve system just to learn a bit, using solenoids valves and microcontrollers to have everything computarized. To save a few bucks I thought making my own solenoids using magnet wire from my motor junkbox.
    Oh boy... over half an hour trying to open that annoying dc motor, I used everything I had in available, from a drill to screwdrivers. I got really mad I just couldn't open it, grabbed a hammer and start hammering it, after a few hits in the right spot the cap flew away, and it exposed the coiled wire and the magnets, that were shattered after all those hits. It's late now and cutting the motor case to remove the wire might take a while, so that's for tomorrow.
    So what you guys do when its needed to scavenge parts from old stuff, sometimes tools are useless.

    Also if someone have ideas for a simple solenoid I'd appreciate it. I thought of using the magnet wire in a straw or maybe a pen case, with a nail inside.
     
  2. jcsd
  3. Sep 15, 2010 #2

    Danger

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    There's almost always some tool that will do it, or at least a combination of two or more.
    I've used side-cutters, torches, a Dremel tool with cut-off wheels, angle grinders, hacksaws... A couple of ViseGrips can be remarkably effective. I always try for minimal damage, in case I'll want the rest of the assembly for something else later, but sometimes that just isn't practical and you have to go for it hard. If the parts aren't too delicate, a hammer and cold chisel can come in handy. (I never entirely rule out the use of high-explosives, but that's just a personal kink. :uhh:)
     
  4. Sep 15, 2010 #3

    turbo

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    Pretty much the same kit as Danger uses. Sometimes, I'll use a carbide drill bit in a Dremel to make holes in a part that I want to fail in a particular way when I pry on it with vise-grips. A Blazer butane micro-torch can come in handy for heating fasteners that are corroded or simply stuck. A decent set of chisels and punches can often come in handy, too.
     
  5. Sep 15, 2010 #4
    This looks like I will need to upgrade my poor man's toolbox.
     
  6. Sep 15, 2010 #5

    Danger

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    As a starting kit which should handle most situations, I suggest:

    6", 8" & 10" ViseGrips
    6" needle-nose ViseGrips
    all sizes of pliers, including needle-nose, end nippers, side-cutters and lineman's types
    small & medium slip-joint (plumber's) pliers
    Dremel tool kit (I prefer the 110VAC as opposed to cordless), with a flex-cable if affordable
    magnetic screwdriver with flat, Robertson and Phillips bits in most sizes (:confused: — I guess only Canuks need Robertsons)
    complete set of jeweler's screwdrivers
    a couple of big screwdrivers, which can double as pry-bars
    3/8" Imperial & metric socket set (compromise; 1/4" & 1/2" is preferable)
    propane torch
    small & medium claw hammers, and one large ball-pein type
    variety of cold chisels
    variety of drift punches, and one centre punch (for starting drill holes)
    good 3/8" or 1/2" cordless drill with all sizes of carbide bits and a screwdriver bit adapter
    small & medium size hacksaws

    Hmm.... I think that should get you through most disassembly projects. If you want to make something, you need a lot more stuff.
    Don't be afraid to use your imagination. I once had to hose-clamp a screwdriver to one end of a Volkswagon torsion bar and turn the other end with a ViseGrip.
     
    Last edited: Sep 15, 2010
  7. Sep 16, 2010 #6
    Thats a nice list, thanks, but I guess that goes to the wish/need list. I'm in high school still and my spare pennies usually go for the project itself.

    The most useful tools for me these years have been some spare manicure set from my mother. It's amazing how much you can do with those, specially with small sized projects.

    The motor is completely disassembled and I made my first solenoid, but it hardly has the strength to move the nail.
     
  8. Sep 16, 2010 #7

    Danger

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    Sorry, I misjudged your budgetary constraints.
    At the very least, go for the multi-bit screwdriver and pliers. Canadian Tire routinely has sets of several dozen screwdriver or drill bits for less than $20, and 3 or 4 piece pliers sets for less than $10. The pliers aren't of great quality, but they're better than nothing. If you live in North America, there is probably some store that offers similar specials. I don't know how things work overseas.
    As for solenoids... I quit trying to make them after the 2nd or 3rd time that I burned myself. They aren't too hard to find, pre-made, if you know where to look. That depends, of course, upon what size you need. For small ones, scrounge around a computer scrap-heap. A mechanical (pin-type) dot matrix printer uses a cluster of solenoids, with the large ends of the pins as the plungers, for the print-head. Most people can't wait to give them away these days. As a bonus, you can also score some decent little motors and gears from the same device.
    Somewhat larger ones can be found in model train track-switching mechanisms (double-acting, yet :tongue2:). New ones are rather expensive, but you might find a used one here and there for a reasonable price.
    For more power, hit an automotive boneyard. The fast-idle regulator from a carburetor is short-throw, but can be leveraged upward. And the Bendix from a starter has one seriously nasty kick.
     
  9. Sep 20, 2010 #8
    I live in the concrete jungles of central America, Panama. We got plenty good hardware stores, it's time for me to do some shopping :).

    I have a junk Inkjet printer somewhere. I know those have stepper motor, which are hard to use without microcontrollers so I haven't taken the time to torture the printer. Does they have solenoids inside? If it does I will cannibalize it ASAP.
     
  10. Sep 20, 2010 #9

    Danger

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    Unfortunately, inkjet printers do not. It's the old impact (pin) type that did.
     
  11. Sep 20, 2010 #10

    Danger

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    Just a cautionary note here which I meant to bring up when I first read your post... and then it got lost somewhere in a dark corner of my brain. What you suggest is okay for old farts like us who take all measures to ensure safety, but I absolutely do not recommend it for newcomers. A regular drill bit is simply not designed to withstand the 30,000 rpm's that a Dremel pumps out, and can quite violently disassemble itself under load at that speed. Even a tiny piece of steel, when traveling at a few hundred Km/hr, is potentially lethal. Keeping the throttle turned down is okay, but accidents can happen given the way the speed control is mounted on the unit. Mine got away from me a couple of times, and it was frightening. It's best to shell out the extra bucks for a Dremel bit that's made for that purpose, or to use a regular electric drill with your regular bits.
    By the bye, Sakha, on the subject of safety... your first purchase should be a pair of protective goggles. Just about everything that we've discussed here involves an eye hazard.
     
    Last edited: Sep 21, 2010
  12. Sep 21, 2010 #11
    I don't know how protective it can get, but I use some squash goggles than came as a gift when I bought a racket. I also have some lab goggles that my brother used when he was in med school. I believe those offer more protection, but they are really uncomfortable.
     
  13. Sep 21, 2010 #12

    Danger

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    Either one of those should be adequate for basic work.
     
  14. Sep 21, 2010 #13

    turbo

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    I should have mentioned that my "dremel" is a variable-speed type with a flexible shaft. I can be more precise with that than with a drill or a hand-help dremel.
     
  15. Sep 21, 2010 #14

    Danger

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    Ah, that does make a difference alright.
     
  16. Sep 21, 2010 #15

    turbo

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    I've got one of the two-speed hand dremels, too, but you'd never catch me chucking up a conventional carbide bit in that. Too dicey.
     
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