Before,
After
Before (rusty I know, it’s the scrap we could get)
After (all mine except the long one)
After
Before (rusty I know, it’s the scrap we could get)
After (all mine except the long one)
What I did today -instead- of Rocketry.
- Thread starter Charles_McG
- Start date
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I have to think that a nice, neat weld would be easier to achieve if you first sanded or otherwise removed the rust and welded on shiny metal. I have to think so, but I don't really know. And if I'm right, I wouldn't know just how much easier.
Humor me and give it a try (unless someone who knows what he's talking about chimes in first).
Humor me and give it a try (unless someone who knows what he's talking about chimes in first).
I did ask and was told that for practice it doesn’t matter, if you cared about structure integrity then it does but any problems in the actual welding process are removed with MORE POWER to get past the rust.
goose_in_co
Well-Known Member
I woke up this morning to 5" of snow, at 5:30. I got ready to go out and move the white stuff out of my way, but I heard a strange sound in the office that did not sound like the furnace, but more like running water. So I went to the rocket laboratory... errrr.. the basement storage room only to find out that the water softener had lost it's mind and was overflowing the tank, and spilling all over the floor.
I quickly pushed the bypass valve and it stopped the mad rush of water, but there was already water expanding over the floor. I called my wife who joined me in dropping towels to contain the water, and I pulled out the Shop Vac and proceeded to pull up as much of the water as possible. Fortunately it was near the floor drain, so most of the water went in there, however it did expand around the room, so we picked up the floor mats, and moved what we could out of the way. Fortunately, there were no boxes on the floor, as I have shelves in the basement, so the damage was limited to a couple of pieces of poster board, and the rest has fans on it to dry out, which most of it is dry by this afternoon.
Now the fun part of either fixing the water softener, which was 5 years old, or getting a new one. Unfortunately it is full of salt and water, so I will have to drain out the water before it can be moved. That will be another fun job.
Oh, no rockets were harmed.
I quickly pushed the bypass valve and it stopped the mad rush of water, but there was already water expanding over the floor. I called my wife who joined me in dropping towels to contain the water, and I pulled out the Shop Vac and proceeded to pull up as much of the water as possible. Fortunately it was near the floor drain, so most of the water went in there, however it did expand around the room, so we picked up the floor mats, and moved what we could out of the way. Fortunately, there were no boxes on the floor, as I have shelves in the basement, so the damage was limited to a couple of pieces of poster board, and the rest has fans on it to dry out, which most of it is dry by this afternoon. Now the fun part of either fixing the water softener, which was 5 years old, or getting a new one. Unfortunately it is full of salt and water, so I will have to drain out the water before it can be moved. That will be another fun job.
Oh, no rockets were harmed.
I wouldn't be too worried unless the neutral line is connected to the earth. Usually things designed for AC allow for reversed connections for normal safe operation. We have to design our spectrometers to work with normal or reversed mains. The safety regulators can't trust electricians.
Agreed. I just hate that the instructions aren't consistent. And I absolutely HATE switching the neutral line, when the hot line is the correct switch. May make no difference in the long run but still....
The neutral line must never be switched. It is against code here, and I would think in the US as well.
One every light fixture I've installed the black wire (hot) goes to the the center of the socket where the small tip of the base contacts and the white (neutral) wire goes to the base threads.
Clean the surfaces with an angle grinder with a 60 or 80 grit disk. Your welds will be much better.
It can make a great deal of difference in the long run! It can kill someone down the road. Of course anyone working on wiring should make sure that relevant circuit breakers are off, but mistakes do get made. One can expect - should never assume but may expect - that the switched line is the hot line, and the unswitched line is neutral. If those are reversed, contact with the unswitched line can be fatal.
Never Switch The Neutral!
Indeed it is.
Right. The central contact is hot and the thread is neutral so that incidental contact with the thread is not fatal. No one turns off the breaker to change the bulb in a lamp, right?
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@prfesser, on reflection, it occurs to me that perhaps you didn't mean what we thought you mean.
Did you mean "And I absolutely HATE switching the line that's labeled "neutral" on the device."? That is, switching the line that's actually hot but indicated to be neutral by the fixture? If so, then you're not so wrong. If you use the correct wire colors and use tape to relabel the fixture then it's OK, albeit undesirable.
But if you meant what we thought you meant, switching the line that actually the neutral from the breaker panel and not switching the one that's hot, then the admonitions above stand.
Charles_McG
Ciderwright
The expectation of switching the hot side of AC made it hard for me to adjust to the DC practice of putting controlling relays on the ground side. After a little gesparken while changing out a valve solenoid (at the winery) and then going and looking carefully at all the newer lab plants, I had a chat with the equipment manufacturers about why they do it that way with DC.
I understand why it's that way for some applications and it still feels weird. And it seems to be done in other applications where I don't understand the reason. So yea, I'm with you.
Cl(VII)
Chris Bender
Yesterday I fell victim to walking in a relatively new house in the dark before caffeine. I smashed my little toe on the sofa leg to the point that it is purple, my entire foot is swollen and I'm not enjoying shoes. It was already mounted "sideways" due to previous injuries so it's not like it is structurally relavent, but dang does it hurt.
Not happy as I was supposed to run a trail race this weekend, and that is looking really unlikely now.
Not happy as I was supposed to run a trail race this weekend, and that is looking really unlikely now.
Woke 230am, browsed Imgur and TRF, fed cats, drove wife to hospital (which is where I am now) to have a 2cm kidney stone pulverized and a stent removed and new one inserted. Pretty routine, I have no worries.
That sounds like it's broken.
Tape it to the toe next to it, Ice packs to reduce swelling. Advil or or other NSAID, not tylenol; bring inflammation down. It may be painful for a few weeks; hope not. That'll be $50. Of COURSE I'm a doctor! (okay, wrong kind, sowhut? )
Anecdote follows, ignore as desired:
Years ago I broke a toe. Wife said "go to the doctor". "No; all he'll do is xray it, tell me it's broken, tape it to the toe next to it, and charge me $88." Taped it myself, saved $87.98. So...
Just a few weeks later, Elder Daughter broke her toe. SWMBO: "Take her to the doctor!"
He xrayed it, told us it was broken, taped it to the toe next to it. $88. An I-told-you-so moment.
FWIW it's a motion-activated fixture and on-off is done internally/electronically. It should work whether I use the connections shown on the fixture markings or the instruction sheet directions. But since I'm unsure of which terminal on the fixture is switched, I'm going to wait for guidance. So far that is not forthcoming from FEIT.
When using transistors (BJTs, FETs,) to switch power on or off, it is practically much easier to do a low-side switch. For example a N-channel MOSFET is turned on or off by"Vgs". This means for a low-side switch (switching the ground side), the control voltage would be 0 or a small positive voltage. But for a high-side switch (switching the supply voltage), the control voltage would need to be either the supply voltage, or above the supply voltage (and the controlling logic may not "know" what the supply voltage is). There are other ways to do it with P-channel MOSFETs, but generally the control is more complex and compromised for a high-side switch, when using solid state devices.
I don't know why it would make any difference when using relays.
if only you did this,That sounds like it's broken.
Anecdote follows, ignore as desired:
Years ago I broke a toe. Wife said "go to the doctor". "No; all he'll do is xray it, tell me it's broken, tape it to the toe next to it, and charge me $88." Taped it myself, saved $87.98. So...
Just a few weeks later, Elder Daughter broke her toe. SWMBO: "Take her to the doctor!"
He xrayed it, told us it was broken, taped it to the toe next to it. $88. An I-told-you-so moment.
There is a description of how to make an xray machine in Scientific American's "The Amateur Scientist." Uses 50's technology. Please. Do. Not. And don't make the atom smasher either. Transmuting elements for fun and profit is not profitable.
true, it's also expensive, power supplies aren't cheap.There is a description of how to make an xray machine in Scientific American's "The Amateur Scientist." Uses 50's technology. Please. Do. Not. And don't make the atom smasher either. Transmuting elements for fun and profit is not profitable.
Ps I would love to make a farnsworth fusor someday, those are cool as all get out.
Ben Franklin had it backwards. DC current runs from Ground to Positive, not Positive to Negative.
And we have been doing DC backwards since then
I broke a little toe some years ago. I didn't even tape it, just ice and naproxen sodium. When I told my doctor about it the next time I saw her, a couple of months later, she said all they'd have done was tape it to the two around it. "Oh, the little toe? Yeah, they wouldn't have done anything."That sounds like it's broken.
Anecdote follows, ignore as desired:
Years ago I broke a toe. Wife said "go to the doctor". "No; all he'll do is xray it, tell me it's broken, tape it to the toe next to it, and charge me $88." Taped it myself, saved $87.98. So...
Just a few weeks later, Elder Daughter broke her toe. SWMBO: "Take her to the doctor!"
He xrayed it, told us it was broken, taped it to the toe next to it. $88. An I-told-you-so moment.
the little toe is possibly the part of you, you care the least about.
But you can just remove the heavy lead-glass front from an old CRT television of computer monitor. Give it a bright blank white screen video signal, and enjoy the rays.
And in lower power stuff, like using TTL chips to drive LEDs, the output pins are capable of sinking more current than they are of sourcing.
No, those use electron guns I believe so its elemental particles your enjoying!
To be fair, he had no way of knowing, and might as well have flipped a coin. (He did have justification for his guess, but it turns out to have been bogus. Not worse than no notion at all, but also not better.)Ben Franklin had it backwards. DC current runs from Ground to Positive, not Positive to Negative.
And we have been doing DC backwards since then
When the electron beam strikes the phosphor it produces x-rays as well as exciting the phosphor to glow. The phosphor is on a comparatively thin piece of glass, and there's a second, thicker piece of lead-glass that's there to physically protect the first piece and also to block the X-rays.
If you were to remove the glass with the phosphor on it, there's be no vacuum around the cathode and you'd get to electron beam at all.
https://en.wikipedia.org/wiki/Crookes_tube
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