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Karmudjun

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  • Homemade Bandsaw by DIY Enthusiast

    Lokisangel - are you stating that the build is one of a table saw (tablesaw) versus a bandsaw that has a table (as most all do) and both miter (mitre) slot and fence rig?A - it uses a continuous blade as most bandsaws use.B - it has a depth of cut that is limited by the bandsaw throat (the width from the blade to the returning blade path and structural support for the upper wheel).C - The table does not move in height - it is fixed height, and can only tilt, to adjust the cut you raise the upper guide bar.D - A table saw (sometimes referred to as a shop saw) or a stationary saw was first described in the mid to late 1700's as a means of using the flat disc wheel saw, and in America the table saw idea was credited to a Shaker Woman who designed a treadle powered spun-toothed wheel for cutt…

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    Lokisangel - are you stating that the build is one of a table saw (tablesaw) versus a bandsaw that has a table (as most all do) and both miter (mitre) slot and fence rig?A - it uses a continuous blade as most bandsaws use.B - it has a depth of cut that is limited by the bandsaw throat (the width from the blade to the returning blade path and structural support for the upper wheel).C - The table does not move in height - it is fixed height, and can only tilt, to adjust the cut you raise the upper guide bar.D - A table saw (sometimes referred to as a shop saw) or a stationary saw was first described in the mid to late 1700's as a means of using the flat disc wheel saw, and in America the table saw idea was credited to a Shaker Woman who designed a treadle powered spun-toothed wheel for cutting wood "continuously" as opposed to the reciprocating "pit-saws" of the day, large saws that cut in one direction and and required a man in a pit and a man atop a log to operate.*A band saw uses a continuous blade that cuts in one direction (like the pit-saw) and isn't designed to cut in the reverse direction (as later cross-cut saws for two operators to fell trees - teeth set to cut in both directions), the band saw requires a return path for the blade limiting the width of any cuts possible (throat of the saw) - and the returning blade must be protected in the structure so as not to cause injury while focused on the cut at the table side.Every other commenter who called you on your 'correction' it absolutely right. The current band saw, stationary saw, shop saw, cabinet saw, and contractors saw models are commonly known as table saws. The band saw - unlike the previous list - has an equal component above the cutting table necessary to house the upper wheel and keep the cutting adjustment guide post stable. Nothing above the table saw is necessary except for safety, and a sliding fence is use - as with a band saw - along the side of the blade but is completely unnecessary for the actual action of the saw. Those distinct differences between a functional table saw (including the sliding table saw models) and a functional band saw are evident across the field.In short - you are incorrect, DIY Enthusiast built a nice little band saw.

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  • Karmudjun commented on JON-A-TRON's instructable Portable Hot Tub
    Portable Hot Tub

    LoriE1: I too couldn't find an ecotemp l5 at that link, but here is a link to camping world's offering at a higher price (6 years, up 30%, not really inflation but everything has to come from China....)https://www.campingworld.com/eccotemp-l5-portable-...The 30% increase in cost does not include the LNG portable tank - your average outdoor gas grill tank - nor does it include a means of securing the heater to your 9' above ground pool close enough to your electrical service - you have to install your own re-circulation system or use your above-ground pool's filtration system.From what I know about above-ground pools, the smaller ones use a submersible filter system you just toss in when you are not enjoying the pool, and run it intermittently and then adjust the chemicals. That system wou…

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    LoriE1: I too couldn't find an ecotemp l5 at that link, but here is a link to camping world's offering at a higher price (6 years, up 30%, not really inflation but everything has to come from China....)https://www.campingworld.com/eccotemp-l5-portable-...The 30% increase in cost does not include the LNG portable tank - your average outdoor gas grill tank - nor does it include a means of securing the heater to your 9' above ground pool close enough to your electrical service - you have to install your own re-circulation system or use your above-ground pool's filtration system.From what I know about above-ground pools, the smaller ones use a submersible filter system you just toss in when you are not enjoying the pool, and run it intermittently and then adjust the chemicals. That system would work if you it meets the particular tankless water heater's required gpm or Lpm flow rates within the range of 20-80 psi. That requires some figuring - what is the discharge rate of the existing filter pump system, will it flow 13 Lpm or 1.5 gpm against that pressure head of 20-80 psi?If so, then it comes with a 'garden hose' adapter, so the plumbing would not be a problem - just run the filter into the tank water in port and run the output to the opposite side of the above-ground pool from your submersible water filter/pump. Jon-Atron suggests not only mounting the heater solidly (they need to be secure for the flame orientation and hot gas exhaust to flow properly, outside it isn't a precision requirement but when installed permanently it must be plumb and oriented precisely to avoid accumulation of exhaust fumes or gas collection if the flame is blown out), but he suggests a baffle housing around the heater to allow free flowing combustion air but no gusts of wind that would extinguish the flame. So someone with carpentry skills or metal working skill would need to fabricate something specifically for your installation.In this environment - no smiles possible through masks - it might cost a little legal tender to get such a portable heater secured and protected from gusts - but two things to keep in mind: First: your 9 foot pool has quite a few more gallons or liters of water than Jon-Atron's hot tub, but you may not want the water in a 9 foot pool to hit the hot tub temps. To achieve the warmth you want, you may need to size up the heater to something that might run 5 gas/m or 18 L/m in order to heat your pool within one day's time.Second: With a higher flow rate, would your existing pump system keep up AND provide the pressure necessary to keep the tankless heater running? They have pressure switches that monitor the water pressure, if it falls too low it indicates water is not flowing and the heater will shut down for safety. Running it with inadequate flow and pressure would certainly frustrate you with repeated safety shut downs - so if you size up or if your existing filtration unit is too weak, too little flow of water per minute - you will need to add a larger circulation pump or filtration system to your pool. If both of those issues seem solvable with a little shopping (my sister was able to trade in her above-ground pool's filter system for a larger one since her yard has evergreen trees that shed a lot of pollen and particulates - the one that came with the pool could not keep up. Yes, she smiled nicely (impossible with a mask on) and was able to trade in her old filter for a larger submersible filter. Much better system but I don't know how much it cost for the upgrade - she is retired and isn't rolling in cash and it was 5-6 years ago....just saying.Thirdly - If those two concerns are met with a little forethought, don't be surprised that your pool cools quickly. An insulating wall would help, I don't know what you have around the outside of the pool, if it is metal, a layer of insulating wrap like Jon-Atron used might be the thing to speed up the heating and slow the thermal loss. Something solid between the liner and the metal wall might be most efficient and affordable. 1/4 inch of 3/8 inch foam insulation boards may be the easiest liner insulation for an above-ground pool set-up.I hope some of this helps you or anyone else willing to read my rambling prose. I agree with the author - this outdoor watering thing would need solar heating or LNG heating to be affordable, electrical costs would be prohibitive for the benefit received. Plus you can always move the tank to your gas grill and enjoy the use of your paid for gas when it is too hot to need a pool heater!

    While this is a 6 year previous post, it is the first time I've seen it, and it has me thinking. I'd like a hot tub for my older arthritic joints - some my own, one purchased at great recovery costs - but this is slightly smaller and somewhat 'younger' than I can manage. I will read and re-read this instructable to figure something out that might work. I have a LNG grill, I have the tanks required, but no hot tub or any water pumps lying around. This is a great idea and you implemented it well. Thanks for posting even though you could not win any competitions - you absolutely are a winner in y book!

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  • DIY Bench Grinder to Belt Sander Conversion With Templates

    Thanks for the excellent video. I especially like the mistakes - which proved you weren't following a 'storyboard' to the nth degree. But it flowed so smoothly and was concise, that is to be appreciated!I help with pinewood derby workshops and am looking for ways to skirt the high cost of equipment or the transport of my heavy tools - this looks sturdy & functional. With cub scouts I'd have to rig a hands and dust shield for the use. Your instructions and your 'enough power - measure twice-drill once' caveats make me think I manage this. Never thought of it before even though I have wanted a stationary belt sander myself.Thanks

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  • Desktop Pi Hardware Assembly

    Awesome build! I was wondering what exactly this could be, I didn't realize it was primarily a 3-D printer intruction (plus the sourcing the online accessories). Now that the newer RPi's can boot from a drive, it more than makes sense to do this as a desktop! Great job, I like all the detail work you did - the slots to hold everything and how neatly it comes together. Really Good Work!

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  • Karmudjun commented on WilkoL's instructable Bat Detector
    Bat Detector

    I've done a precursory read and the math on the method you didn't use doesn't seem to hold up - but I've got to say this is a very nice little project that doesn't require the math to be write to explain the theory behind analog heterodyne signaling.I've noticed that you wrote "sounds at 40 kHz and you tune the detector to 45 kHz, you will have a signal at 95 kHz that you filter away (it isn't audible anyway) and an audio signal at 5 kHz." Since this is such a nice build and it works without the heterodyne method, this is just for any edits you may wish to make - and please do. I see power input labels might be useful edit....The f1 and f2 of heterodyne (Different powered signals) should add to and subtract from each other. So a bat at 40 kHz and a detector signal at 45 kHz shou…

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    I've done a precursory read and the math on the method you didn't use doesn't seem to hold up - but I've got to say this is a very nice little project that doesn't require the math to be write to explain the theory behind analog heterodyne signaling.I've noticed that you wrote "sounds at 40 kHz and you tune the detector to 45 kHz, you will have a signal at 95 kHz that you filter away (it isn't audible anyway) and an audio signal at 5 kHz." Since this is such a nice build and it works without the heterodyne method, this is just for any edits you may wish to make - and please do. I see power input labels might be useful edit....The f1 and f2 of heterodyne (Different powered signals) should add to and subtract from each other. So a bat at 40 kHz and a detector signal at 45 kHz should result in at least two frequencies, (but lets not discuss harmonics) of 5 kHz - (45 kHz - 40 kHz) and 85 kHz (40 kHz + 45 kHz), not 95 kHz. The 5 kHz should be audible with your speaker. A tune-able variant would use the heterodyne method and I think I'll try to build such a circuit myself before going with the amplification and filtration method. With a heterodyne (more analog) design, the variation in the bat signalling should be spectacular. I've got to see how this digital version of bat signal detection yields your output before I start researching old heterodyne circuits!It is a beautiful build, like I said above, I will look at this and build it when the my boys are old enough to help me solder the circuit....nothing like seeing something they build or help build do what it is intended to do! Thanks for the schematics & look forward to the corrections before I download the pdf!Sorry for any missed edits in my comment, I have cracker dust (and probably cheerio and more) under my keyboard making a few keys stick, I might have missed them and there may be "f" & "v"s missing from some words. I notice their stickiness & lack of display.

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  • Karmudjun commented on AussieAlf's instructable Cartesian Diver
    Cartesian Diver

    Well described and nicely done! I was thinking I should do this for my boys (and my wife's science classes) as I was reading your description. Then I made it down to step 3 and read your 'on the fly' instructions.....you reversed it! Okay, I know, brain-fart, absence seizure, whatever.....then I read #4 "How It Works" and you nailed it precisely. It is clear you suffer from the bane of humanity - being human! We may all think faster than we write or type, and sometimes we get ahead of ourselves. Clearly - VERY CLEARLY - you don't get ahead of yourself in the doing as this is one of the best homemade or hand crafted Cartesian divers I have even seen. A joy to read this instructable, and I know how to spend some time while in limited quarantine!Thanks! Great job!

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  • Karmudjun commented on TrestinB's instructable Play Structure
    Play Structure

    Very nice TrestinB - your children are lucky. I grew up with a Telephone lineman as Dad of my friends, he had something similar with rope swings (no slide) on telephone poles. I'm grinning just thinking about how high up we were playing on that tiny little platform. He took the poles up and flat roofed them for our Tennessee summer sun. I'm sure it is all gone by now, the neighbors likely thought that structure peeking out behind the house was an eyesore. But Dads really go for solid and use their resources! This is a very nice write up, you nailed all the requirements for something that will stay stable and relatively level during your children's active years. If this is your keeper house - it may last through your grandchildren!I like the solid ladder - again such overkill, but you don…

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    Very nice TrestinB - your children are lucky. I grew up with a Telephone lineman as Dad of my friends, he had something similar with rope swings (no slide) on telephone poles. I'm grinning just thinking about how high up we were playing on that tiny little platform. He took the poles up and flat roofed them for our Tennessee summer sun. I'm sure it is all gone by now, the neighbors likely thought that structure peeking out behind the house was an eyesore. But Dads really go for solid and use their resources! This is a very nice write up, you nailed all the requirements for something that will stay stable and relatively level during your children's active years. If this is your keeper house - it may last through your grandchildren!I like the solid ladder - again such overkill, but you don't want a significant other terrified that the ladder gave way when one of your children or their friends decide to run down the ladder and slip in their exuberance. Don't ask me how I know that happens...just trust me. My wife thinks I build things so the kids can get hurt - but after the broken bones from climbing trees, I'd rather they fall from my play structures than climb a tree and swing on (and then off) a branch....I actually wish they wouldn't fall at all, too many hours at the local children's hospital. Still - your children are lucky, keep building for them and they will carry on the tradition!

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  • OpenVent-Bristol V2.0 COVID-19 Rapid Manufacture Ventilator BVM Ambubag

    Fascinating when specialists put their expertise to work solving a serious community need. I am very familiar with forced ventilation and I wanted to clarify something in your intro - intubation and mechanical ventilation are only ONE of the treatments for the severe hypoxia of a Covid-19 pneumonia - even if they have already been on some oxygen but can't keep up with their gas exchange needs, we start with something called "CPAP" or continuous positive airway pressure using a face mask. The device provides whatever oxygen percentage you dial in (most CPAPs for home use are room air or 21% Oxygen) and can delay the need to paralyze and intubate a patient. BiPhasic or BiPAP also can be used, for those who have trouble exhaling it will not only push air their way, when it senses a…

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    Fascinating when specialists put their expertise to work solving a serious community need. I am very familiar with forced ventilation and I wanted to clarify something in your intro - intubation and mechanical ventilation are only ONE of the treatments for the severe hypoxia of a Covid-19 pneumonia - even if they have already been on some oxygen but can't keep up with their gas exchange needs, we start with something called "CPAP" or continuous positive airway pressure using a face mask. The device provides whatever oxygen percentage you dial in (most CPAPs for home use are room air or 21% Oxygen) and can delay the need to paralyze and intubate a patient. BiPhasic or BiPAP also can be used, for those who have trouble exhaling it will not only push air their way, when it senses an attempt at exhalation it will gently assist in exhalation. When forced ventilation with a paralyzed patient is failing due to reduced surface area in the lungs (the alveoli get filled with inflammatory fluids and white blood cells reducing the effective lung volume and creating more ARDS problems as reduced compliance, etc.) we can opt for something here in the States called ECMO. Normally used on children who have tremendous powers of recovery, Extra-Corporeal Membrane Oxygenation provides some of the gas exchange needed while the lungs heal. This developed for the 'blue babies' syndrome where a septal defect or another genetic abnormality of the heart or lungs limited the baby's use of their lungs efficiently. With adults it is the last ditch effort since you need to keep the lungs inflating and deflating, and we prefer to turn our patients to help with the 'dependent' part of the lungs. When an adult is connected to a membrane lung and a pump connected via two large blood filled tubes, we cannot easily turn those patients without risk of disconnection and massive exsanguination. Further, the adults need more gas exchange than an ECMO can provide - but the ventilation pressures on their lungs can be reduced to a level where the lymphatics help drain the fluids out. I applaud your hard work, if I had to put someone on a ventilator and only had your device available, being able to slip the ambu-bag into a device with such monitored settings would be fast and effective. I've seen a less involved design out of one of our University Hospitals that provided the timed ventilation with only airway pressure monitoring - all the other parameters would be normal intensive care monitoring devices. I have to say your design is nicely monitored and easily (and understandably) adjustable. Thanks!CEPool, MD

    Here in the United States our litigious society has truly made medical grade ventilators both complex and costly. The complexity is required, ventilation is not a one setting therapy, you can do more harm than good if you approach ventilation that way. For our national certification, the durability of the device must be proven with many 'worst case scenarios' attempted - not to cause the device to fail because we can, but to prove that the device WON'T fail under the worst of normal circumstances. When you add in product liability - that drives up the cost of US ventilators. Since they are made with proven and durable parts (not off the shelf parts), most everyone can trust the quality control behind each of the parts used. Off the shelf doesn't have that quality control factor. I'd use t…

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    Here in the United States our litigious society has truly made medical grade ventilators both complex and costly. The complexity is required, ventilation is not a one setting therapy, you can do more harm than good if you approach ventilation that way. For our national certification, the durability of the device must be proven with many 'worst case scenarios' attempted - not to cause the device to fail because we can, but to prove that the device WON'T fail under the worst of normal circumstances. When you add in product liability - that drives up the cost of US ventilators. Since they are made with proven and durable parts (not off the shelf parts), most everyone can trust the quality control behind each of the parts used. Off the shelf doesn't have that quality control factor. I'd use this ventilator - but only due to the fact I know I can trust the build. How long the sensors would last in real world conditions? That is the only issue I have and I trust all my respiratory staff to be able to manage a patient on a device like this if it did fail.

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