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OverTheTop

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Went to 3D print at work today and the extruder temperature went up seriously quickly, overshot and the firmware tripped out. Started looking at PID values and all sorts of things. Turned out one of the Mech engineers had changed the hot head for some reason and put a 12v heater in where there should gave been a 24v one. That was about 100W extra. Returned the PIDs and it is doing nicely again.

Also found a fan that was jammed so I need to order some spares.
 

dr wogz

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Trying to comprehend a new method for tolerance stack calculations..

We, like many manuf. & Eng. departments, tend to 'not' do proper tolerance stack calcs. One of the newer engineers in the dept. is quite good at it, and has a particular method he is trying to teach us. But I am an old goat, and seem to have trouble learning this new methods / understanding it.. and I seem to be quite set in my ways.. (gut feeling / looks about right / experience method..)

And it's frustrating that I don't get it on the 1st pass / 1st few tries..
 

jqavins

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I'm very curious. I only know two ways to do a tolerance stack-up. One is to just add all the worst case values, which is dead simple. The other is a "Monte Carlo" (which most people do wrong) which gives less than the absolute worst case, but can give you a 3σ or 4σ or whatever level of confidence you choose, and is still pretty simple (under certain assumptions, and virtually impossible to do correctly otherwise).
 

dr wogz

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1) he is a Russian engineer, and probably one of the more competent engineer I've worked with (and equally arrogant.. but maybe that came from his years as an officer in the Russian navy..) He is also a big fan of the TRIZ method, which a lot of design people should know!!

2) He also did a lot to work in France, as is quite adept with ISO / DIN standards for tolerancing parts / fits.

This method he shows is literally a 'walk in the park'. You start at one point, and work [walk] your way thru the dims to the desired end point. You put arrows to denote if you are adding or subtracting the numbers, and you then get the stack bay adding the pluses, then adding the negatives, then getting eh difference of the two. The tolerances are then all added up to get your total ± .. its seems easy, and seemed pretty straight forward.

But in his method, you are expected to start looking at hole clearances & screw dimeters & such.. It becomes a very thorough method.. but one you need to practice a bit with to be confident..

I'm old school: add them all up then add / subtract the total tolerances.. So, while his method is similar, there are differences in how he sets things up & follow thru the part / parts.

And, as mentioned, I'm old school, and do mainly sheet metal. I'm used to suppliers giving ±.001 or .002 on parts, even over bends.. so a .281" hole for a 1/4-20 screw will fit fine..

He does also touch on the sigma-6 method too, to ensure you are within the ball park / depending on how many parts you are making..

 

boatgeek

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Got my second shot of Moderna this morning. So far, it just feels like I got a shot. We'll see if that holds in 12-24 hours.

I also tried to shop for a Zune on Ebay at lunchtime. They're surprisingly hard to find for such an awesome piece of technology.
 

mbeels

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Got my second shot of Moderna this morning. So far, it just feels like I got a shot. We'll see if that holds in 12-24 hours.
Hope that goes well, I'm coming up on my second shot pretty soon as well.

I also tried to shop for a Zune on Ebay at lunchtime. They're surprisingly hard to find for such an awesome piece of technology.
I have to ask, what makes the Zune "awesome" over another generic media player?
 

OverTheTop

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Went shopping for new couches, coffee table and entertainment unit. Old ones are nearly 25 years old. Time to modernise.

Started looking for a 3D printer to buy for when we get some holiday money refunded.
 

boatgeek

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I have to ask, what makes the Zune "awesome" over another generic media player?
It was a tongue in cheek nod to the Bill Gates conspiracy theories about the vaccine. I’m pretty sure the Zune is not in any way awesome. Apparently too deep a reference. :D
 
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mbeels

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It was a tongue in cheek nod to the Bill Gates conspiracy theories about the vaccine. I’m pretty sure the Zune is not in any way awesome. Apparently too deep a reference. :D
WHOOOSH! Right over my head. I had to look up what a "Zune" was, so by then, the joke ship had sailed and I hadn't even gotten my ticket yet. I'm a little slow 😄.
 

KC3KNM

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It was a tongue in cheek nod to the Bill Gates conspiracy theories about the vaccine. I’m pretty sure the Zune is not in any way awesome. Apparently too deep a reference. :D
Hey man, I really liked my Zune HD.

I also really liked Windows Phone.

Everything I love dies, apparently.
 
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jqavins

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I also tried to shop for a Zune on Ebay at lunchtime. They're surprisingly hard to find for such an awesome piece of technology.
ROTFL!

Hey man, I really liked my Zune HD.
Oh, sorry man, I didn't mean to offend.

Anyway, my car (Ford Escape) stopped going (again) on Wednesday. Early last month it was the transmission. This time the turbo seized up. Had to get a cab home Wednesday night, then a cab back to a rental car office (Enterprise) in the morning yesterday. Then found out the repair will take a lot longer than we expected (about eight or nine days) so I shopped around for a cheaper rental (after striking out looking for a shop to fix the car sooner).

So, my wife picked me up from work (Hornell, NY) early in the Enterprise car and we drove an hour to the nearest place (Dollar at the Corning/Elmira regional airport) to get the cheaper one. Then back to the Hornell to return the car to Enterprise, then finally home (Howard). Including a stop at CVS on the way back to Hornell, it was a four hour ordeal.

The worst part is that it was a nice car from Enterprise and a cramped econobox from Dollar, but it will cost us $300 less in the end.
 

dr wogz

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ROTFL!

So, my wife picked me up from work (Hornell, NY) early in the Enterprise car and we drove an hour to the nearest place (Dollar at the Corning/Elmira regional airport) to get the cheaper one. Then back to the Hornell to return the car to Enterprise, then finally home (Howard). Including a stop at CVS on the way back to Hornell, it was a four hour ordeal.

The worst part is that it was a nice car from Enterprise and a cramped econobox from Dollar, but it will cost us $300 less in the end.
I would consider that a pretty drive! (But I get it, this is your "home" and you know the roads pretty well..)
 

jqavins

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I would consider that a pretty drive! (But I get it, this is your "home" and you know the roads pretty well..)
And I didn't mention that it was raining hard, and after a full day at work. And with the aggravation of the second major car repair in two months casting a pall over the whole thing.
 

kuririn

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The worst part is that it was a nice car from Enterprise and a cramped econobox from Dollar, but it will cost us $300 less in the end.
Current rental situation here is limited supply, high demand. I hear that some standard rentals are going for over $200 a day now. Tourists are renting U-Haul trucks and vans instead.
Nice thing about Enterprise is that they pick you up, don't have to find a ride to get there.
 

jqavins

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Depending on the distance and time. If I'd asked the Enterprise here in Hornell to pick me up at home at 7:30 (about 16 miles and the office doesn't open until 8:00) I'm sure I'd've been SOL.
 

teepot

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I'm hunting the pack rat that is in my garage. These things are smart. It avoided all the traps I set last night. I'll go to Home Depot and get some sticky traps today. I'll get it hopefully sooner rather than later.
 

jqavins

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Woke up and looked out the window. There is effing fresh effing snow on the effing ground on the effing first effing day or effing May! That's effing enough, mother effing Mother Effing Nature!
 

Cl(VII)

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Dropped some orders at the PO, counted laps at my kids’ swim-a-thon team fundraiser, went on a 30 mile bike ride, and ate sushi for lunch. It has been a good day so far, but now I need a nap.
 

Wayco

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Woke up and looked out the window. There is effing fresh effing snow on the effing ground on the effing first effing day or effing May! That's effing enough, mother effing Mother Effing Nature!
Come on Joe, tell us how you really feel.
Just finished a hike to the “fallen roof” cliff dwelling in southern Utah, near Bluff.
7C12FE1C-9D2B-4B43-9F7E-557F067B0319.jpeg


Great hike, wonderful weather, and one of the best preserved dwellings we have seen in all the sites we have visited over the last twenty years exploring Comb Ridge. Parts of the fallen roof are at our feet, and you can see the handprints of ancient Puebloans overhead.
 

hobie1dog

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Finally got my 5 ft. tall Mirage M3si speakers put in the bedroom and my wife hooked all the wiring, well she also put them in the bedroom on a dolly as they are 135 lbs. each. Now I have to get 2 surround speakers put in there for surround sound as I'm not a fan of just stereo. I've got to find some bigger speakers for the garage too.
 
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