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  • Recovering Bass Guitar Speaker Cabinets

    The outside covering shouldn't affect the acoustics of the cabinet to a degree that you would notice. I've seen cabs recovered in roll-on truck bed liner, which actually turned out quite well. I would go for it.

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      • Cupboard With Folding Table and Lights
      • Guitar Suitcase
  • 2000 Watts Induction Heater

    I may be able to help with some of your questions. (numbers from picture)4) any 12 volt regulator should work. It is only driving the fan and LED, so just make sure it can handle the amps your fan requires.5) The LED is only to show the unit is on, so any kind of LED would work.6) Not sure the values of the resistors - Seems like 1k ohm would be better. I say this because the resistor in series with the LED (at 12 volts) would need to be higher than 220 ohms, more like the 1k ohm range. I would bet it is supposed to be 1k.7) any fan will work. Just make sure it is big enough (if stuff starts getting too hot, smelling bad or letting smoke out, its not big enough) and you can hook it to 12 volts and make it work.9) These are standard standoffs, meant to support PCBs above a base. They…

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    I may be able to help with some of your questions. (numbers from picture)4) any 12 volt regulator should work. It is only driving the fan and LED, so just make sure it can handle the amps your fan requires.5) The LED is only to show the unit is on, so any kind of LED would work.6) Not sure the values of the resistors - Seems like 1k ohm would be better. I say this because the resistor in series with the LED (at 12 volts) would need to be higher than 220 ohms, more like the 1k ohm range. I would bet it is supposed to be 1k.7) any fan will work. Just make sure it is big enough (if stuff starts getting too hot, smelling bad or letting smoke out, its not big enough) and you can hook it to 12 volts and make it work.9) These are standard standoffs, meant to support PCBs above a base. They are being used here as connectors, not their intended purpose. They are metal and tall enough that you can connect the thick wire to easily. The exact measurements are not needed. Use what you can find, or use a different type of connector that you are familiar with that can handle large amperage.11) 1N821 vs 1N821A - they are the same zener diode, only the "A" version is 10 ohms where the no-A version is 15. Either should work, I would think.12) Not sure, I didn't catch what henrys the inductor was.13) The exact size and composition of the PCB doesn't affect how the device works. I would go for the cheapest option. Choose what is prettiest to you. Or make your own (that's what I do). Or use perf board. Or drill holes in thin plywood and then wire components up manually with wire under the plywood. Or plexiglass.Hope this helps.

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  • Reuse Old Mobile Phone Batteries

    Power sources in parallel increase amps, power sources in series increase volts. So parallel would be the way to go.Now for theoretical discussion....I'm just curious if putting two batteries in series could have a benefit in special cases. For example, you want 12V out, and you have 2 x 3.6V batteries. If you put them in series, you would get 7.2V, closer to the 12V you desired (but no increase in amps). Would that decrease the amount of heat produced since it is closer to output voltage, and possibly extend the battery or converter lifetime? Would it also extend capacity somewhat since its still pouring from two buckets, so to speak?

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  • ShannonW49 followed Katod and abzza
      • Multiscale Hollowbody Recycled Wood Guitar With Composite Fretboard
      • Marklar 7, New Step in Pnewmohudralic Jet Machines
      • 6 String Bass Guitar Made With Wood From Recycling Been
      • Tales From the Chip: LM1875 Audio Amplifier
      • Headphone Dummy Load
      • DIY External Volume Control
  • Multiscale Hollowbody Recycled Wood Guitar With Composite Fretboard

    Very nicely done. I'm a programmer and bass player that likes to build amps and effects, too bad we don't live closer :) You've made some nice looking instruments. I commend you on developing your own composite. I wish I had the courage to build my own bass.Just a couple of minor notes for your English (sadly I only know one language). I'm not sure what it is called in Ukraine, but in U.S. we refer to your toss rod as a truss rod. Also, a trash or recycle container is a bin (instead of been, pronounced the same). Hope this helps.Keep up the good work. If you build anything and don't have a home for it, just contact me and I'll send you my shipping address :)

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  • First Blow. Getting Into Blacksmithing With Empty Pockets

    Thanks for posting. I'm about to remake a furnace for melting aluminum. Just need something big enough for my small crucible. I was thinking of using a small fridge, with the door facing upwards and lined with a plaster/sand/vermiculite refractory. However - I happen to have an old water heater sitting as an eyesore in my yard. Its now a target.Gonna use a propane burner, gonna line it thick and round to swirl the heat. Thanks for the info, it'll be a great help. Wish I had a welder... ;)

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  • -- How else are fleas and crumbs supposed to gather the necessary raw materials to build their log cabin homes? What you can't see in the photos are the tiny little saws and axes he made to help them. He left out the tiny chainsaws as an attempt to be green, but we can't really know how the little beardians will go about doing their thing.-- He should start good underbeard management to avoid possible beard fires in the future.

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  • Very nicely done! Thanks for writing this, you are by far a braver man than I! I have wanted to make my own bass for a long time, but lack the proper tools, space, time, money, motivation, brainpower and beer. Maybe if I gain a couple of these I will follow your lead.

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  • I've done this for several years. Here's a couple of tips:-- I use thin glossy magazine paper for the transfer. Works well, and is cheaper and easier to find. It may take a try or two to get the subtle differences down, but works pretty much the same way.-- I use 2:1 hydrogen peroxide to 9% white vinegar. I add the board, then sprinkle the salt in. It will immediately start fizzing. When the fizzing slows, I add more salt. The salt adds ions to allow a better reaction (etching). I also add an aquarium bubbler to the mix (put hose in so it bubbles in the solution) to keep it moving around. This keeps the solution mixed (no "dead spots" of used reactant directly above the board) and keeps the gunk from building up on the board itself (to be scraped off).-- I have started …

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    I've done this for several years. Here's a couple of tips:-- I use thin glossy magazine paper for the transfer. Works well, and is cheaper and easier to find. It may take a try or two to get the subtle differences down, but works pretty much the same way.-- I use 2:1 hydrogen peroxide to 9% white vinegar. I add the board, then sprinkle the salt in. It will immediately start fizzing. When the fizzing slows, I add more salt. The salt adds ions to allow a better reaction (etching). I also add an aquarium bubbler to the mix (put hose in so it bubbles in the solution) to keep it moving around. This keeps the solution mixed (no "dead spots" of used reactant directly above the board) and keeps the gunk from building up on the board itself (to be scraped off).-- I have started using HCl instead of vinegar. This is hydrochloric acid, and is also know as muriatic acid. Muriatic acid is a common product available at home improvement stores for swimming pool maintenance. Comes in a big box or a gallon jug for a few dollars, and is more than you will ever need.----- 2 parts H2O2, 1 part HCl - Using this has some advantages. It etches faster and can be "renewed" (you don't have to throw it away). By bubbling air through it, you cause some other reactions to happen the converts the used-up solution to drop its copper and become useful again. Just store it (safely) and you got it ready for next time. (any chemist want to explain it?).----- First time you use this, it will be very fast, so be careful (fast and mean, might want to just dissolve some copper into it instead of etching a board right off). As the copper dissolves into it, it becomes cupric chloride (and turns green). This is what will do the etching later instead of the raw HCl, and it will slow down a bit. The cupric chloride is really what you want, you want it green. That is what is "renewable". You can bump the acid levels back up by adding oxygen (bubble air through the mixture).

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  • Very cool. No other words for it.

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  • lol, beat me to it :) yeah 12v/1000 ohm=0.012 amp -- safe for LED.

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  • Thank you for taking the time to write this instructable. VERY well done. I've attempted (with blind ambition and little knowledge) to build speaker cabs, always using what I currently have (drivers from old/donated speakers, etc). Always with so-so results. I know about the maths, formulas, concepts, and so on, but it always seemed like an overwhelming amount of information. So I tended to ignore it out of fear :) Thanks for 1) providing good sources of information and calculators, 2) encouraging me with the knowledge that even the calculators disagree and that experimentation is required, and 3) boosting my "speaker morale" so that I'm excited to try again. Lots of very good information that you have discovered in here. Thanks again.

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  • - Hmm, personally (like I mentioned in previous) that is how I would do it. That is how I learned to do it. For a beginner or advanced, if you have a good gap between traces (not tiny "is that touching") then you don't have to worry about shorts. Especially if you test with a multimeter in cleanup. I am not trying to say you are wrong, I am saying that is how I do it. For those who learn from this and continue on, leaving the ground plane will save time and achieve better electronic results. For those just beginning, keep it as simple as possible and just make it work (remove the ground plane so you can see better what is going on). - And sorry, I don't believe its "horrible" advice. You do as you learn. I was just trying to help with additional information. …

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    - Hmm, personally (like I mentioned in previous) that is how I would do it. That is how I learned to do it. For a beginner or advanced, if you have a good gap between traces (not tiny "is that touching") then you don't have to worry about shorts. Especially if you test with a multimeter in cleanup. I am not trying to say you are wrong, I am saying that is how I do it. For those who learn from this and continue on, leaving the ground plane will save time and achieve better electronic results. For those just beginning, keep it as simple as possible and just make it work (remove the ground plane so you can see better what is going on). - And sorry, I don't believe its "horrible" advice. You do as you learn. I was just trying to help with additional information. I am a BEGINNER to CNC routing of boards, but not at electronics, so this instructable is not for me? I'm slightly offended.

    Strange, I've tried that and it didn't seem to work. Lemme try againThree line breaks

    No problems. Its often hard to judge inflection through text :) Very nice instructable, by the way. I do understand what you are saying and I agree. Please keep up the quality work!

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  • Personally, I would make sure you have good isolation on your traces, and leave the copper "field" (or plane) there. Then connect your ground to the plane. Just verify there are no shorts between non-ground traces and the ground plane. You can also connect all ground points to the plane (without traces if possible) and have as much of your "unused" copper be ground.This helps with RFI, saves time, and gives a ground with slightly less impedance for the circuit. I etch PCBs instead of routing them, but I use this ground plane on every board I etch. The benefits and savings are just too good to pass up.If you look at professionally done boards (take anything apart) and you will see there is no bare areas. Any non-populated areas are ground planes (or power planes o…

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    Personally, I would make sure you have good isolation on your traces, and leave the copper "field" (or plane) there. Then connect your ground to the plane. Just verify there are no shorts between non-ground traces and the ground plane. You can also connect all ground points to the plane (without traces if possible) and have as much of your "unused" copper be ground.This helps with RFI, saves time, and gives a ground with slightly less impedance for the circuit. I etch PCBs instead of routing them, but I use this ground plane on every board I etch. The benefits and savings are just too good to pass up.If you look at professionally done boards (take anything apart) and you will see there is no bare areas. Any non-populated areas are ground planes (or power planes on some double+ sided boards). There is a reason for this. Cheaper, faster, and electronically better.My two cents...

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  • Pretty cool. I've used these same ingredients (vinegar, hydrogen peroxide and salt) as an etchant for making circuit boards. Much easier, cheaper and environmentally friendly than the stinky black ferris chloride normally used.The salt (as someone mentioned already) does speed the process up. Ions and all that. When etching PCBs, I would add more salt when the bubbling slowed. That would "refresh" it and it would start bubbling again. To speed it up more, I added a bubble hose (aquarium air pump and basic clear air hose) to keep the solution moving around.I wonder if you could "age" the metal faster by combining your two steps and using a mixture like I use for etching. I'm thinking maybe 30 minutes to an hour. Its been a bit ago but I think I used two parts wh…

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    Pretty cool. I've used these same ingredients (vinegar, hydrogen peroxide and salt) as an etchant for making circuit boards. Much easier, cheaper and environmentally friendly than the stinky black ferris chloride normally used.The salt (as someone mentioned already) does speed the process up. Ions and all that. When etching PCBs, I would add more salt when the bubbling slowed. That would "refresh" it and it would start bubbling again. To speed it up more, I added a bubble hose (aquarium air pump and basic clear air hose) to keep the solution moving around.I wonder if you could "age" the metal faster by combining your two steps and using a mixture like I use for etching. I'm thinking maybe 30 minutes to an hour. Its been a bit ago but I think I used two parts white vinegar (like 9% I think) and 1 part hydrogen peroxide. The salt - I just sprinkled it in afterwards until it bubbled pretty good. I know it will corrode other metals (I was etching copper), because I accidentally dropped my wedding ring in once and it cleaned it very well (a little too well, the non-gold part was starting to turn dark). It was only in the solution about 30 seconds - long enough for me to find a stinkin' pair of long needle nose to get it out.Anyway, something to consider if you are in a hurry ;)BTW, I have gotten the solution on me with no ill effects. I wouldn't bathe in it, but I'm not going to wear a hazmat suit to use it either. Maybe dried my fingertips out a little after etching several boards and drying them in between dunkings. I'm sure someone can tell me how it will turn me into a raging four-armed mutant zombie, but luckily I've already had all the children I'm going to.

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  • ShannonW49 commented on JasonF205's instructable Faux Brick Walls

    Wow. Very nice. I too like how you made it look like the brick was "exposed", as if plaster had fallen off. Now I'm going to have to close in my garage just so I have a wall I can do this to, heh heh. Yeah, that's it. "Honey, I have to close the garage in now. Gotta make a fake brick wall. Its not a man cave. We can park in the street, it will be OK. NOT a man cave. We don't need that couch anymore, do we?"

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  • Good collection of tips. I don't know how many times I've busted my knuckles trying to cut something (not just plumbing) in a confined place (#1) or been about ready to take a hammer to project with a bolt in a narrow gap (#10).

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  • Nice job. I hadn't considered making my own pickguards, but now I may just try it out. I don't have access to the tools you have, so... Hey, Dremel, get your new hat, here we go! :)

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  • For the first circuit, you mention that your original schematic had only the 100k pot, and then talk about adding the 1M pot to get more options. However, your new schematic shows two 100k potentiometers. I am guessing it is a typo, and one of those should be 1M, but which one?

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  • This is a very high quality instructable with good information. Well done.I was thinking about looking for PLA smoothing info, and lo and behold, your instructable came up. I tried sanding (not wanting to paint), and it discolored my piece, you know, white scratch marks type of effect. I have used acetone on ABS (a lot), and now my speling is not to good (lol). I prefer the smooth, shiny plastic look, so your information about the various chemicals is exactly what I needed.Thanks for your hard work and sharing.

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  • I think you have a future in AIMER (Auto-magically Integrated Machine Emotion Response), a new and upcoming field (that I just made up). Great work, I voted for you.Just one suggestion... You should have a reservoir to collect your tears. I hear they bring top dollar on the black market, you know, Chinese aphrodisiacs and all. Also, a cowbell and mood lightening lights (check out neoPixels). BTW, I have no reason to suggest a cowbell.

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  • Yes, I agree with the other commenters - Nice job on explaining the difference between the various 3d printing technologies. I've been using an FDM printer for a while, and knew some basics on other methods, but your instructable outlined them in a nice, easy to understand way. Thanks for posting!

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      • 8 Transistor Stereo Amplifier
      • Portable Variable Power Supply
      • One Tube AM Radio
  • Love that site (http://sound.whsites.net) Elliott Sound Productions. Lots of good information there about stuff like this. Very helpful. Got me through quite a few projects and problems ;)

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  • These two components form what is called a Zobel network. It is use to prevent the chipamp from oscillating due to the inductive load of the speaker. It also prevents radio frequencies picked up by the speaker wires from getting back into the inverting input of the chipamp through the feedback loop (R1).According to http://www.circuitbasics.com/design-hi-fi-audio-am... (which is about the LM3886 - it uses Rsn and Csn to refer to those two components):"At high frequencies, the impedance of Csn is very low, so high frequency current is shorted to ground. Rsn limits the high frequency current so there isn’t a direct short to ground, which could exceed the current limit of the LM3886. Therefore, smaller values of Rsn make the Zobel network more efficient at filtering radio freque…

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    These two components form what is called a Zobel network. It is use to prevent the chipamp from oscillating due to the inductive load of the speaker. It also prevents radio frequencies picked up by the speaker wires from getting back into the inverting input of the chipamp through the feedback loop (R1).According to http://www.circuitbasics.com/design-hi-fi-audio-am... (which is about the LM3886 - it uses Rsn and Csn to refer to those two components):"At high frequencies, the impedance of Csn is very low, so high frequency current is shorted to ground. Rsn limits the high frequency current so there isn’t a direct short to ground, which could exceed the current limit of the LM3886. Therefore, smaller values of Rsn make the Zobel network more efficient at filtering radio frequencies, but it also increases the cutoff frequency, which in turn reduces it’s effectiveness." I've seen these on a lot of chipamp circuits with varying values of the two components, but usually very close to what is here (4.7 ohm + 220nf, 2.2 ohm + 100nf, etc). So I suspect there is a bit of a dance around a narrow line of efficiency and effectiveness.BTW, nice article!

    No, they are not the same. Speakers are inductive, while resistors are not. This means that the speaker will have different resistance at different frequencies. The resistor will have the same resistance at all frequencies.So, for testing, the resistor is better because you get the same resistance across the spectrum. Plus, if you screw something up, a resistor is a lot cheaper than a speaker ;)

    Yeah, check out the schematic at http://electronics-diy.com/lm4780-gainclone-amplif... - it uses bridged parallel amps (4 X LM3886, but would apply to this) to pump out 225 watts into 8 ohms.Hmm, I may need to try this... ;)

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  • Nicely done. I'm looking to create an enclosure, but hadn't thought about see-through materials.I'm about to print out parts to mount the printer to the 2 foot square board its sitting on (stability) and move the power supply and control board and panel off the printer to the front of the board for a clean and accessible work area. Containing the heat in my drafty garage is a must. Having the control board and power supply outside of the heated area would be a good idea. Gotta keep that stuff cool.This, or something very similar, is perfect for me. Thanks for the ideas!

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  • Sorry that people are "upset" that this is not a capacitive touch switch or the diagram is not uber professional. With such a simple design, a simple schematic is all that is needed. Everybody understood it, so what is the problem?It could be a dual touch (one for on, one for off) if the contacts were close enough together so that a "touch" bridged the gap between two points - On touch = left MOSFET pin and +, Off touch = left pin and -. I might just do that for fun :) I just built a 3d printer, so I could make a face place with two finger-sized indentations that have two small wire-sized holes in each.Thanks to your notes I learned the functional difference between enhancement and depletion mode MOSFETs. I had read the technical jargon and educational materials, …

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    Sorry that people are "upset" that this is not a capacitive touch switch or the diagram is not uber professional. With such a simple design, a simple schematic is all that is needed. Everybody understood it, so what is the problem?It could be a dual touch (one for on, one for off) if the contacts were close enough together so that a "touch" bridged the gap between two points - On touch = left MOSFET pin and +, Off touch = left pin and -. I might just do that for fun :) I just built a 3d printer, so I could make a face place with two finger-sized indentations that have two small wire-sized holes in each.Thanks to your notes I learned the functional difference between enhancement and depletion mode MOSFETs. I had read the technical jargon and educational materials, but your notes simplified it so that it clicked in my head. Makes so much sense now.Oh, and yes, there is a lot of very technical information that could be inserted about all sorts of stuff here, but that is not the point of this instructable. KISS is. (Keep It Simple Stupid - something I try, but often fail, to live by)Keep it up!One criticism, easily fixed - Maybe you copy/pasted your text, but the line breaks (which broke it up into paragraphs here) in the introduction section confused me when I started reading.

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  • Nice instructable. You could use a PVC piece that is threaded, and have a top on the compartment to store your valuables. Then the rattling marble won't be hitting your valuables when you shake it.

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  • Nicely done. I now understand how brushless motors work, the various ways it can be implemented, and some pros and cons for each method. Thanks for your work. I really enjoy well done "concept instructables" because I always like to know why things work, not just how to do it. Also, I didn't realize reed switches could switch on/off that quickly. (or that mechanical switch, for that matter)

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  • lol, and add in a rich, handsome husband doing the dishes behind her...Actually, that would be a cool mod - use the camera idea, detect the person's outline, and change the scenery behind them. It could be like a portal-mirror, with a tropical beach scene (and a rich, handsome husband bringing drinks).

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  • Nice one. voted.This is a wealth of info. I live in Texas, and the Brazos river is at the edge of my back yard. I have found large brick-red clumps of raw, clean clay, and made little smiley faces to dry on flat river rocks, but never knew what I could really do with it. This has inspired me to go collect some and "play" a little more seriously with it. Thanks for the info, and time you took to put it down into a nicely illustrated and easy to read format.

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  • Daisy chain two of these circuits, or figure a way to load balance, to charge two batteries at once. Then you only dump when both are full. Or expand to three or more batteries.Or... Set up another relay and have it charge one until full, then switch over (via relay) to charge the next battery.Or... instead of a battery, run a heating element in a hot water heater. Then use heat exchange to get your energy back out ;)

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  • A good recommendation. I do this as well using a Sharpie permanent marker. I do not know what a Dalo pen is, but may be similar. The Sharpie's ink is etch resistant, but can wear out if it is in the etchant too long. On some boards, when I've had weak etchant and it took a while, I had to remove the board and re-color some of the areas multiple times. Some still came out with tiny pin-holes speckled around.

    When I started doing this, I used a dremel tool with a very small drill bit. I forget the size, but I special ordered several that were specifically for this purpose. Later, I got a small jeweler's drill press which worked much better.Getting the passive component holes just right is not very crucial. Just as long as they are "connected" to the required traces and nothing else. For 8 pin DIPs, I always use sockets, and the pins on the sockets (and chips as well if you don't use sockets) are a little forgiving. They can move around a bit (bend, twist, "stretch", etc), and the holes don't have to be perfect. The stuff I do doesn't go much over an 8 pin or a pentawatt type package, but I've never had a problem drilling the holes.Occasionally, the bit will "walk…

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    When I started doing this, I used a dremel tool with a very small drill bit. I forget the size, but I special ordered several that were specifically for this purpose. Later, I got a small jeweler's drill press which worked much better.Getting the passive component holes just right is not very crucial. Just as long as they are "connected" to the required traces and nothing else. For 8 pin DIPs, I always use sockets, and the pins on the sockets (and chips as well if you don't use sockets) are a little forgiving. They can move around a bit (bend, twist, "stretch", etc), and the holes don't have to be perfect. The stuff I do doesn't go much over an 8 pin or a pentawatt type package, but I've never had a problem drilling the holes.Occasionally, the bit will "walk" a little, but that never really caused a problem. One thing to help that is to etch a tiny hole in the middle of the trace where you want the pin to come through. Include it in your mask. Then the lack of copper helps guide the drill bit and keep it from moving around until the hole is deep enough to keep it in place.The biggest problem I had was figuring out what size drill bit to get and use. I'm not at my project bench now, so I can't check them and tell you what I use. The second problem was slightly crooked holes when I used my dremel tool (not perfectly 90 degrees), but that really wasn't a problem.I have actually used a thumb drill (manual pencil shaped drill, similar to an exacto knife with a drill bit on the end) to do the holes in PCBs before, and it did a surprisingly decent job. Went faster than I expected as well. Just press down with one thumb while spinning with the other hand. Put a small piece of cloth over the end so you don't get a blister on your thumb after a while from the friction.I would recommend not worrying too much about the holes, as they are not as hard as you think, and do not have to be as precise as you think. In my opinion, its harder to keep the very thin traces from getting gaps from leaving it in too long. Long live solder bridges!

    Lye as an etchant? Did you mix it with anything or just use it "raw"?I have heard of using projector sheets, but never tried it. How well does that work and can you reuse the sheets? I've always used the magazine paper (shiniest and thinnest I can find, with econo-mode off and printer settings to dump maximum toner).

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  • I think he does want to dim it, but the LED panel he has wasn't designed to dim. Using PWM should allow him to dim the panel.Current limiting sure wouldn't hurt, even if its just a current limiting resistor in series. Constant current supply and current limiting resistors are to prevent the LEDs from getting too much current and burning themselves out. I would recommend putting a resistor in there along with the PWM, just in case. I've burned enough LEDs that I always use resistors now.PWM (pulse width modulation) sends quick pulses of voltage instead of a steady DC voltage. This allows you to slow the pulses down and make the LEDs appear to be not-as-bright, when in reality they are simply going on and off at a slower rate. BTW, the on-off pulses are so quick that the human eye can…

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    I think he does want to dim it, but the LED panel he has wasn't designed to dim. Using PWM should allow him to dim the panel.Current limiting sure wouldn't hurt, even if its just a current limiting resistor in series. Constant current supply and current limiting resistors are to prevent the LEDs from getting too much current and burning themselves out. I would recommend putting a resistor in there along with the PWM, just in case. I've burned enough LEDs that I always use resistors now.PWM (pulse width modulation) sends quick pulses of voltage instead of a steady DC voltage. This allows you to slow the pulses down and make the LEDs appear to be not-as-bright, when in reality they are simply going on and off at a slower rate. BTW, the on-off pulses are so quick that the human eye can't see it. Also, the pulses allow the LEDs to cool slightly in the off cycle, which prevents them from getting so hot and burning out. However, it is still possible to burn them, so I recommend the resistor. Its cheap protection.LEDs by themselves will take all the current available to them, with no limiting control. Having a resistor in series with them allows you to specify how much current they can have. The value of the resistor depends on the voltage being supplied and the maximum amount of current your LED(s) can handle. For example, with 12 volts and an LED that can handle 30 miliAmps - R=Volt/current - 400=12/.030 - so, a 400 ohm resistor would limit it to .03 amps at 12 volts. I personally would bump that up just a tad, maybe 470 (higher ohms is less current) because LEDs look just about as bright when near (not at) their maximum, but live a lot longer. (FYI, you also have to deal with resistor values, good luck finding a 400 ohm resistor).

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  • I found a solution to the X/Y axis being swapped, at least for me. Using an Uno with a 2.4 TFT LCD Shield. The controller on the shield is covered, so I don't know what it is. Cheapo from China.In SPFD5408_TouchScreen.cpp:Find the lines that say "int TouchScreen::readTouchX(void)" and "int TouchScreen::readTouchY(void)", and then swap the X and Ys. These are at the end of the file, with just one small section after them.That way every time it wants to read what the X coordinate of the touch is, it receives the Y coordinate instead, and vice versa.That fixed swapping the X and Y axis, but now X is backwards (reads high when it should be low). To fix that, find the line (in the same file, towards the middle) that says "return TSPoint(x, 1023 - y, z);" and …

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    I found a solution to the X/Y axis being swapped, at least for me. Using an Uno with a 2.4 TFT LCD Shield. The controller on the shield is covered, so I don't know what it is. Cheapo from China.In SPFD5408_TouchScreen.cpp:Find the lines that say "int TouchScreen::readTouchX(void)" and "int TouchScreen::readTouchY(void)", and then swap the X and Ys. These are at the end of the file, with just one small section after them.That way every time it wants to read what the X coordinate of the touch is, it receives the Y coordinate instead, and vice versa.That fixed swapping the X and Y axis, but now X is backwards (reads high when it should be low). To fix that, find the line (in the same file, towards the middle) that says "return TSPoint(x, 1023 - y, z);" and change it to "return TSPoint(1100 - x, 1023 - y, z);" This is the same fix that other people have suggested. What this does is take the X value of the touch, and subtract it from 1100, which effectively reverses the X coordinate. Example: If X is 25, it should be on the left, because 0,0 is upper left. However, it is registering at the far right instead because X is backwards. If we subtract it from 1100 (or some number close that works for you, experiment), then 1100-25 = 1075. 1075 should be at the far right, but because X is backwards, it registers at the far left. Ta-Da, fixed.

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