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Everything posted by Externet

  1. Greetings. Do you know of a hydraulic piston or piston-cylinder assembly that I can re-purpose instead of fabricate/re-invent the wheel ? Similar to brakes, much larger diameter, like 50 to 100 mm. To work in reciprocating motion, only about 50mm travel, ~<10 strokes per second, up to 5000 psi. (not with a seal for rotating shafts) It is to produce pulses of hydraulic pressure. Like a driven small engine using it as a hydraulics reciprocating compressor 🙄 -Images borrowed from the web-
  2. Two days ago, saw in TV news there is trouble in California as solar generation is exceeding the handling capability. Too much production at certain times of the day forcing utilities to decrease conventional generation and trouble in transmission lines. They were talking about a 'duck curve' and about eliminating subsidies and tax incentives to solar installations to discourage solar. 🙄 Now am pissed. Discouraging solar to raise profit of utilities that have had the pan by the handle $ince day 1. So... Houston, YOU have a problem with greed. ---> https://www.eia.gov/todayinenergy/detail.php?id=56880 ---> https://www.washingtonpost.com/climate-environment/2024/04/22/california-solar-duck-curve-rooftop/ ---> https://www.energy.gov/eere/articles/confronting-duck-curve-how-address-over-generation-solar-energy
  3. Hi all. It is very easy to write with lead metal on paper and other surfaces. Same with tin metal, learned the same happens with indium metal. Where pencils ever made initially with soft metals ?
  4. Thanks, studiot. No flux incorporated, solid not hollow wire. Melts correctly with my plain typical soldering iron for electronics work. Unable to find data about it. Highly likely sourced from a local Sylvania incandescent light bulb factory that closed doors. While searching, noticed a trend from solder manufacturers on not telling the alloy contents but christening it with a letter soup to identify their product. Interesting how they have had open formula information to the competitors before. ---> https://buy.solder.com/product/5-Solder-Alloys-Wire-Kit/
  5. Hello. Received a present, a 20 lb solder wire roll of 89.5% Sn; 10.0% Sb; and 0.5% Cu. Does anyone know what is intended to solder ? Radiators... electrical... plumbing... ?
  6. Hi and thanks. Yes, I may have posted a contraption of 1200W solar panels heating a 20 litres water container indoors to boiling! temperature and releasing its heat also after sunset. (lasts to about midnight). I use it only in winter. Posted also a spiral length of black PVC pipe on the roof feeding the standard electric water heater inlet with pre-heated water for a much less energy consumption in summer. And a photovoltaic roof solar system heats and supplies all the house all year from the surplus grid-tied generated. My electrical bill has been $0.0 the last 37 months and the system paid for itself last month.
  7. Hi StringJunky. All sizes from a grain of sand to ~20mm; goji, lychee, pistachio, caper, culantro, peach, plum, These pomegranates germinated well, like 70 of 100 : First time trying now to germinate in the refrigerator ~5C : wintergreen.
  8. Tried that way and it is worse. Currently using soil in capped clear these by a window :
  9. Hello. Germinating moist seeds in capped containers sometimes spoils the seed with mold / fungus growth. Is there any chemical placed on a absorbent tissue attached under the container cap that will not harm the soil or the seed ? Would vinegar work ? A piece of moth ball ? I usually microwave the soil in 30ml. containers for germination but not always effective.
  10. Thanks. For summer water inlet of 15C, a desired water outlet of 50C, in a 20C air ambient basement, may work as the 'air conditioner' heats the water with its 'outside the window' condenser and cools the dwelling with its 'inside the window' ducting the evaporator. Sounds good for tropical climates, if use of hot water is extensive. In other words, cooling a 'window' airconditioner condenser with water instead of air. That is pumping the heat inside the dwelling into a water tank. For winter, a 10C water inlet, a desired water outlet of 50C, in a 10C air ambient basement; the 'reversed air conditioner' would warm the water with its 'outside the window' condenser and cool the basement with its 'inside the window' evaporator degrading the temperature differential unless expelled out the dwelling. Where is the "hot air in" in the image at post #5 coming from ? From the heating furnace in the dwelling ? Yes, should say "hardly and barely warm air in" Sounds complicated contraption for little if any performance. For sure the industry has tested and retested this as a very profitable wallet wringer product before putting such in the market. But for winter weather, smells not much convenient. -Image borrowed from the web- Oh ! I see it now ! The energy to heat water comes from the house furnace in winter. But to sell the thinghy, advertises "It takes little 120VAC" instead of your power hungry standard water heater. Yes, sure, and the furnace consumes the additional energy. Agree the heat pump outside units do perform well for heating a dwelling in limited cold weather But not for an inside unit.
  11. OK. Found this, kind of shows its workings. What really makes me scratch my head is in summer I could get cool air ducting it for the house, and hot water. Great. How is the behavior in winter, the contraption installed on a cold basement.
  12. How does it work ? The outlet is hot water. What is the energy input ?
  13. China to replace the U.S. in what ? Productivity, industry, laziness, human rights, engineering, finances, health, technology, tourism, patents... ?
  14. Greetings to all. How to calculate the differential in hardware needs (a radiator size and coolant mass and ...) ? A plain simple automobile uses a number of litres of water as coolant on a radiator of such and such dimensions. If the water specific heat capacity is 4,181 J/kg°C , a very high number compared to many other fluids- is replaced by plain motor oil / transmission fluid; what does it translate to ? --> Doubling the area/volume/fanning of its radiator ? Tripling ? As replacement of water based coolant in ICE engines, transmission fluid can: - Eliminate rust progress or prevent it, - Eliminate boiling at operating temperatures, - Eliminate pressurized circuits, - Eliminate specialized orange, green, whatever coolants, - Increase efficiency with hotter combustion if wanted by thermostat choice, - Even used transmission oil at $0 is good enough, - Better heat transfer wettability - No more blown head gaskets perhaps ? - No freezing at comparable temperatures... Are these above correct ? Is there more ?
  15. Thanks, gentlemen. Enjoyable videos. Mostly focused in assembling the watches, not much on how their parts are made. Still wonder what equipment does cutting the micro-teeth in gears, how a drill bit to perforate and form a 'jewel' is made . And why not, a step deeper; how the machine that makes those drill bits is made. There has to be a hiding engineering universe behind... that centuries ago was all by hand skills. Escapes imagination. Following the clue of searching for videos; found parts made with mostly automated modern equipment ---> https://monochrome-watches.com/inside-vaucher-manufacture-fleurier-how-exactly-watch-parts-are-manufactured/ And to drool: ---> https://www.youtube.com/watch?v=Nlw1NQQGlXI ---> https://www.youtube.com/watch?v=UdY-p5g7HS4 Will look for an Antikythera replica...
  16. It has always been a mystery to me. HOW are watch parts made ? What equipment, machinery takes to make gears a few millimetres small with such degree of precision and replication ? Ladies watches having even tinier gears, jewels shaping, machining, dimensioning? ... are impressive. And it has been happening for a couple of centuries plus, since the machining techniques were less than in their infancy... And to make it harder, how are the machines that make timepieces parts made ? Please share whatever you know; I will hold my jaw from dropping. Thanks.
  17. Understood and agreed. Thanks for the good intention.
  18. That is what I noticed...
  19. The longevity shows a loooong time after first opening the jar, slowly consumed along many months, perhaps to a year with no signs of degradation
  20. Greetings. Please move to the appropriate section, as chemistry, biology, nutrition... as deserved. I do not know where. What is in the peanut butter product that survives very long time -perhaps years- with no refrigeration, and does not degrade, gets moldy or rots ? The label of the product does not reveal any preservatives, and I believe it is true. Is there other legume/nuts/something paste/product that also exhibits such longevity ?
  21. Hi. Seen several contraptions shown in youtube videos that seem to pump somehow and a container works in partial vacuum. There is maaaany videos doing the same in many styles. Can someone explain what is going on ? I dislike to send you to a particular link, just search terms "water pump" within youtube for your own choice. If you really want an example link, try ---> https://www.youtube.com/watch?v=23Afu1ViH3E and dozens appear at the side column. They all use a container, and mostly asian construction. Perhaps there is one in english.
  22. Am sorry, I was unable to locate a re-run on the web to answer you. Seems there is several types of the contest and not entire broadcasts available. It was about 20H00 hours ET the 29 of May on Scripps TV (semifinals ?) But 'tiny' ; 'either' are words that come to mind. And will never understand who decided that 'law' is not written 'lo'
  23. Hi. It is happening now, and would like to know if the host/conductor would be capable to compete with the kids... But, first I must disclose I have never gone to school in U.S. or any other English speaking country and learned English as third language at an academy. So, guilty. What brings me to post is the mystery when the host tells several pronunciations of the subject word. WHAT is the host reading to give different ways to pronounce the word in question ? Is the host reading this senseless <censored> I think is called phonemes ; a few of them to tell the kid the ways it can be pronounced ? And sad to see how the words selection is being shifted to other languages; either because they are running out of words in English or to make it beyond difficult. Today they presented a Japanese word and a Korean something fitted in the contest. Horrible. Does this spelling thing exist in other languages ? Thank you.
  24. Hi. Is it safe to assume these products typically calling for 21% alcohol in the ingredients label to be ethanol and not methanol or other, even when not intended to ingest ?
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