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Looks like the rear most arm locks failed. On my lift, once they lift of the ground a gear engages and they will not move. Also, this is 100% a fear of mine. Just a single misjudgment of balance and this happens. I bought two pole jacks, one for front/rear just in case.
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Dec 2, 2021 00:14
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the spyder posted:Looks like the rear most arm locks failed. On my lift, once they lift of the ground a gear engages and they will not move. The rear arm swing locks failed well after the balance was compromised here. Having seen the splines on the studs of a fair few swing locks this doesn't really bother me, as the forces those locks were subjected to aren't what the engineers had in mind or within range of the typical use case.
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Dec 2, 2021 02:29
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Yeah that looks to me like he forgot to put a pole under the back after pulling the engine out, or didn't put it on the lift planning for how much that was going to change the center of mass. It's absolutely a fear of mine, though the ever present "hmm, this concrete floor was poured in the 50s or 60s and has cracks in it, will today be the day it splits around the mounting studs and the lift and truck tip over on me?" Dread overrides it, which is why I typically don't even think about going under a vehicle over 3500lbs (half the lift rating) on my lift unless it's got jackstands under the lift arms, and shake test everything before I consider it even on light vehicles.
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Dec 2, 2021 03:34
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slidebite posted:I love how the girlfriend hardly seems fazed. Kinda looks at the guy on the jack like, well? Same thing happened to me while I had the engine out of my C6. I unbolted the front subframe to make installing the engine a little easier as it tucks under the cowl. Forgetting that the transmission in the back was heavy enough to make it tip over backwards. Fortunately I was only on jackstands (placed on the jacking points), and the weight imbalance wasn't so bad - I sat on the core support and phoned my dad to come over and throw a jack under the transmission! In hindsight it makes sense since the car is made of plastic and all the weight is in the drivetrain. If you're ever working on one of these on a lift, throw a transmission jack under the transmission! (or engine) Pomp and Circumcized fucked around with this message at 00:39 on Dec 3, 2021 |
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Dec 3, 2021 00:37
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NoWake posted:yup, not much else to do at this point but go home for the rest day/week/career Pretty much. I like to assume the boss is there in the office and he’s going in to resign. kastein posted:Yeah that looks to me like he forgot to put a pole under the back after pulling the engine out, or didn't put it on the lift planning for how much that was going to change the center of mass. Biggest problem with the Corvettes is that they only have the 4 designated lift points, so only thing to do would have been to use a lift or stand under the rear once it was up.
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Dec 3, 2021 20:34
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My coworker just shared this picture of a failed "weld" on his two post lift. This is on a strap that helps the end resist tr moment load. 
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Dec 3, 2021 21:46
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TIG welders are expensive, just give everybody hot glue guns.
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Dec 3, 2021 21:59
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that was structural paint
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Dec 3, 2021 22:11
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StormDrain posted:My coworker just shared this picture of a failed "weld" on his two post lift. This is on a strap that helps the end resist tr moment load. Somebody flip the photo for the true horror.
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Dec 3, 2021 22:50
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Dec 3, 2021 23:19
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Omg I am dying. I just added eyebrows and sent it back to him.
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Dec 3, 2021 23:42
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StormDrain posted:My coworker just shared this picture of a failed "weld" on his two post lift. This is on a strap that helps the end resist tr moment load. Well that's loving horrifying
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Dec 4, 2021 01:38
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kastein posted:Well that's loving horrifying Ya here's some more color. He has had the lift for a while. 10k rated. Uses it for a side by side and cars. He put a dually Super duty on it which scaled around 8500lbs on it and this thing gave way. So the straps aren't needed until they are and they are really needed. Warranty would only replace the front arms and he told them to gently caress themselves and he tore down and rewelded the ones on the rear. Of course now can he trust anything to be welded right? I don't recall the brand but its not a Bendpak or Rotary.
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Dec 4, 2021 01:52
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Its a bend something alright.
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Dec 4, 2021 02:32
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Welcome to Muppet Garage! My assistant Beaker here will now demonstrate our new no-strap lift system!
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Dec 4, 2021 04:14
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StormDrain posted:Ya here's some more color. I would bet Atlas. Or anything sold by Greg Smith Equipment. I'll never cheap out on a lift after watching them fail under static load testing.
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Dec 4, 2021 06:18
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I'd argue a reason enough not to use "jerry rig" is that the term doesn't make sense. Jerry rigging and German engineering feel orthogonal. I understand jerry rigging as a field repair that does the necessary, whereas German engineering is a too complicated solution that fails in the field. The nazis lost because they didn't jerry rig enough.NoWake posted:yup, not much else to do at this point but go home for the rest day/week/career How does the insurance payment compare against the expense of finding, hiring and training a new employee. I would think someone who has hosed up this bad to be highly sought after in the work force, there's at least one gently caress up he won't commit again.
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Dec 4, 2021 08:23
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I thought "Jerry Rig" as a term came from the Allies finding equipment at the tail end of WWII when that storied German engineering had to be bodged up to keep running in the face of critical POL/parts/expertise shortages.
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Dec 4, 2021 08:28
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Memento posted:I thought "Jerry Rig" as a term came from the Allies finding equipment at the tail end of WWII when that storied German engineering had to be bodged up to keep running in the face of critical POL/parts/expertise shortages. Yeah as far as I know "jerry rigging" is the term used for an american botching german equipment to make it work.
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Dec 4, 2021 10:49
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SEKCobra posted:Yeah as far as I know "jerry rigging" is the term used for an american botching german equipment to make it work. I don't think so. One of the biggest issues facing Germany once the tide swung the other way was a lack of spares. The factories were cranking out tanks and new projects, but not manufacturing any spare parts. Combined with the high level of engineering complexity in the vehicles (interleaved road wheels, transmissions that needed the turret removed to change, etc), this led to a lot of Panthers, tigers, and the like being out of service for broken parts over battle damage. The soldiers would try and fix them with whatever they had available, leading to the phrase. If you want to learn about tanks, watch "The Chieftain" and "The Tank Museum" on YouTube. sharkytm fucked around with this message at 16:40 on Dec 4, 2021 |
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Dec 4, 2021 16:26
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the spyder posted:I would bet Atlas. Or anything sold by Greg Smith Equipment. I'll never cheap out on a lift after watching them fail under static load testing. Looks like this: http://www.championautolift.com/economy-two-posts.html Evidently these guys went to black to copy Bendpak's recent moves.
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Dec 4, 2021 17:02
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So as an aspiring welder, what went wrong here? What kind of welding is this? How is it even possible to lay down that large bead with so little penetration?
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Dec 4, 2021 18:23
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ryanrs posted:So as an aspiring welder, what went wrong here? What kind of welding is this? How is it even possible to lay down that large bead with so little penetration? Not being a pro myself my guess is they spent too much time holding the gun or stick on the piece that the weld is stuck to and not the other.
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Dec 4, 2021 18:56
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It's pretty easy to do that with mig and have it look nice but peel right off especially if you don't prep the material. It looks like they didn't remove the mill scale and treated it like a glue gun rather than a mig welder, you can't just squirt metal in there and hope it sticks. https://youtu.be/lSNXTgmNbxk
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Dec 4, 2021 19:05
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Does it also factor in that the bigger piece has more thermal mass and, uh, heatsinking ability? (Video looks very relevant but I'm not in a position to watch it right now)
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Dec 4, 2021 20:27
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It's completely possible to make a strong, full-penetration weld on a thick chunk of structural steel, or lay a booger on top that looks like a weld but is barely fused to the base metal and peels off under any load. It's all in the technique. Doing a thick weld properly means you have to do stuff like clean the area, preheat the parts, and work slowly, and all of those things take time and cost money!
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Dec 4, 2021 21:19
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May also want to heat treat it after, depending your application Had a former boss who didn't believe in heat treating, which is fine if you're willing to reweld the same corner on a vibrating bin every month. sharkytm posted:I don't think so. One of the biggest issues facing Germany once the tide swung the other way was a lack of spares. The factories were cranking out tanks and new projects, but not manufacturing any spare parts. Combined with the high level of engineering complexity in the vehicles (interleaved road wheels, transmissions that needed the turret removed to change, etc), this led to a lot of Panthers, tigers, and the like being out of service for broken parts over battle damage. The soldiers would try and fix them with whatever they had available, leading to the phrase. I'm addition, Germans tended to make rolling modifications to parts that made part interchangeability uncertain between even the same models of equipment, on top of dubious QC and poor manufacturing processes. It was apparently not uncommon for maintenance crews to have to modify a replacement part to be able to use it as a replacement for a nominally identical part. EvenWorseOpinions fucked around with this message at 00:33 on Dec 5, 2021 |
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Dec 5, 2021 00:22
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Reading about how WW2 Germany used prisoners as labor, I'm not surprised that quality may have been sketchy. If I was Jewish prisoner making parts for Messerschmitts or Panther tanks or V2 rockets, I'd probably turn a blind eye to if the parts were in spec or not.
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Dec 5, 2021 01:12
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Dr.Smasher posted:Reading about how WW2 Germany used prisoners as labor, I'm not surprised that quality may have been sketchy. If I was Jewish prisoner making parts for Messerschmitts or Panther tanks or V2 rockets, I'd probably turn a blind eye to if the parts were in spec or not. There's some stories of German shells not exploding and when examined, they found a note from a forced laborer saying "this is all I can do for you" https://hushkit.net/2020/04/17/the-b-17-miracle-defying-hitler-with-sabotage/
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Dec 5, 2021 04:22
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One of the big advantages the US had during WW2 was that you by and large managed to make actually interchangeable parts that you could both assemble on actual assembly lines and trivially replace. Meanwhile, German production was still surprisingly artisanal; every single tank was meticulously assembled in place from parts that were adjusted to fit each other. Computer viking fucked around with this message at 05:11 on Dec 5, 2021 |
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Dec 5, 2021 05:07
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The US also had the advantage that the tank factories weren't being bombed every day.
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Dec 5, 2021 07:00
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Cojawfee posted:The US also had the advantage that the tank factories weren't being bombed every day. Not to mention the interference from Hitler.
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Dec 5, 2021 09:13
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sharkytm posted:Not to mention the interference from Hitler. https://www.csparks.com/watchmaking/CycloidalGears/RichardThoen.xhtml quote:The "big wheels" at (Picatinny Arsenal) were adamant and would not permit deviations from the drawings of that era, 1940. They maintained that these gears had been made before so why couldn't Kodak make them? Of course they had, with non-generating milling cutters. We had a war to win and wanted to mass produce these items (with conventional generating cutters) . ... Millions of dollars could have been saved and much better fuses been made if it had not been for the asinine, arbitrary decisions of those who didn't know the "score."
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Dec 5, 2021 09:33
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Platystemon posted:https://www.csparks.com/watchmaking/CycloidalGears/RichardThoen.xhtml Sounds like the hidebound bureaucracy of DoD
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Dec 5, 2021 17:37
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Cojawfee posted:The US also had the advantage that the tank factories weren't being bombed every day. Absolutely, but being able to assemble a working tank from any random selection of spares without much adjustment would presumably also have been a huge benefit to the guys who were being bombed.
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Dec 5, 2021 17:46
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Pigsfeet on Rye posted:Sounds like the hidebound bureaucracy of DoD At least the War Department in those days could count. And (mostly) wasn't swayed by marketing nonsense.
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Dec 5, 2021 19:25
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The Bureau of Ordinance, though…
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Dec 5, 2021 19:26
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Could someone explain what the difference is between a "generating" and "non-generating" cutter? I'm having trouble googling.
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Dec 6, 2021 16:37
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Blue Footed Booby posted:Could someone explain what the difference is between a "generating" and "non-generating" cutter? I'm having trouble googling. Gear generating cutters have the spurving bearing in line with the panametric fam to avoid side-fumbling and reduce sinusoidal deplaneration. Real answer: https://www.youtube.com/watch?v=B0XSsa79Y1w
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Dec 6, 2021 16:53
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StormDrain posted:My coworker just shared this picture of a failed "weld" on his two post lift. This is on a strap that helps the end resist tr moment load. StormDrain posted:Ya here's some more color. This, exactly. I'd definitely invest in some lift-height jack stands if I didn't chuck the whole thing. Powershift posted:Gear generating cutters have the spurving bearing in line with the panametric fam to avoid side-fumbling and reduce sinusoidal deplaneration. God dammit, it's not a retro-turbo encabulator. The basic problem, as I understand it, in the gear scenario above is that cycloidal gears are more difficult to make, and less tolerant of changes in clearances, primarily any change in spacing between the gears. Involute gears are more fault-tolerant, and easier to machine. https://mechanicalengineering.blog/comparison-between-involute-and-cycloidal-tooth-profiles/ I just had my own mechanical failure. Feast your eyes: https://www.youtube.com/watch?v=lUVGwz4CYGo (sound on, or it's not going to be interesting.)        One of those rollers was damned near square...
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Dec 6, 2021 19:47
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