Machinist's Minutes: Fill and penetration make a weld

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  • เผยแพร่เมื่อ 23 มิ.ย. 2024
  • Learn from our past mistakes!

ความคิดเห็น • 14

  • @donmathias1705
    @donmathias1705 5 วันที่ผ่านมา +7

    I'm 66. First welded when I was 13 and fert spreader broke axle. Dad was away on holiday and my grandfather was minding us on the farm. Had watched enough to have a go. Got the axle rewelded and reinforced and operating again. I was hooked. At 16 began my apprenticeship at a very reputable engineering company but because of demarcation and union stuff arc welding was for boiler makers. Not fitters and turners. Gas welding sure to make our own tip tools etc. Times change and learn stuff a bit later and a lifetime of good, bad and ugly welding consider myself quite capable but not perfect. I work in a hydraulic shop and the same attitude exists. Grrr. Well did some cylinders other day and prepped stuff for welding. The expert welded on fittings and then got called away. I was able to machine barrels and then welded on ends etc and second lot of fittings. Rams got assembled and tested. I guess I must be ok because my welds were clean and pressure tight. The "welders" fittings leaked! Only took a year of holding my tongue. Funny, I love quizzing other tradesman about what and why they do stuff. You don't know what you don't know unless you're enquisitive. I'm also happy to pass on tips for manual machining etc. Just frustrating when we get rework that is caused by sloppy attitude, lack of attention to detail, or too lazy to clean and inspect all of the components properly. Feel sorry for clients who don't know their repairs are borderline, but bills are high.

  • @skwerlz
    @skwerlz 5 วันที่ผ่านมา +8

    Good news is you're not a dummy, you're just a hands-on learner. Proof is that you didn't make the same mistake twice. And you're not the only one. I've had to go so far as repeatedly embarrassing engineers in front of their supervisors to get them to leave space for welds in their designs.

    • @melgross
      @melgross 4 วันที่ผ่านมา +1

      They don’t seem to be actual engineers with a degree. Engineers normally spec out welds pretty well. It’s one of the things mechanical engineers learn in school. It’s usually welders who don’t meet. The specs maid down because they don’t understand why something is spec’d that way. Like the difference between a machinist and an engineer. The machinist understands how to machine something, but not really why it has to be made that way. I’ve come across this often. So they modify the part and then it doesn’t meet specs anymore and has to be scrapped. The same problems happen in a lot of bigger companies between design and production engineers. The production engineer gets a design and thinks, “we can’t easily make this” and modifies it so that it they can. Then it breaks and the design engineers look at it and can’t understand why until they realize it was modified. This happens all too often and is a reason why some things fail.

    • @skwerlz
      @skwerlz 4 วันที่ผ่านมา +1

      @@melgross No argument that there are bad apples on all sides of a drawing, plenty of cocky welders and machinists to go around. These two engineers came to mind though because of the context of the video. They'd design large signs with embedded LCD panels but not take into account the space the welds they were calling out would take up so the panels wouldn't fit into their frames. Being stamped drawings we couldn't enlarge the frames the quarter inch required to get clearance. Between the costs of new drawings, reworks, and the production delays there was enough noise to draw the attention of the department head, so he dragged the engineers down to the shop to figure out what was going wrong. We built a frame around one panel to the spec the engineers gave us to demonstrate the problem. Yes these two were actual engineers with actual degrees, their designs were pretty good, they just didn't take into account that welds take up space. These two got dragged down to the shop a couple years later for a similar problem with basically the same result.

    • @melgross
      @melgross 2 วันที่ผ่านมา

      @@skwerlz I’m not saying I don’t believe you. I’ve encountered a lot of odd design problems over the years. It’s just that they should have had at least one course that delineated how this needed to be done.

  • @carolinemcnabb9957
    @carolinemcnabb9957 5 วันที่ผ่านมา +7

    Great as usual . I've met a lot of machinists/toolmakers that had no use for welding and in general looked down their noses at welding processes. Glad you take a practical-balanced approach .

    • @funone8716
      @funone8716 4 วันที่ผ่านมา

      Ya try to find a machinist/welder these days. I guess rare animal, but I wouldn't feel adequate if I wasn't fully capable of BOTH skills. Been at it 44 years now.

  • @douglascalhoun6471
    @douglascalhoun6471 5 วันที่ผ่านมา +2

    Good explanations as a machinist who has also done welding in the past. The biggest difficulty that I see is two dissimilar sizes of material. A lot of people fail to get good penetration on the thicker side by failing to understand that you spend more time on the thicker piece.

  • @copperchatter6890
    @copperchatter6890 4 วันที่ผ่านมา +1

    Love the way this guy explains things!

  • @jabonet
    @jabonet 5 วันที่ผ่านมา +4

    I would love to hear stories of big mistakes and why they happened and what was your mistake when doing them. ❤

  • @haroldsprenkle4173
    @haroldsprenkle4173 3 วันที่ผ่านมา +1

    Got to add a story I remember. Fred, told me this one, he was working in Colorado, got sent by union to take a test for a job on nuke installation, test was test tabs, 2 x 1/2? Hey I am remembering his story here give me a break. Welding machine, every stick rod available, grinders etc. Weld it, bend it, back again, If coupon didn't break you passed.
    Fred said he gapped it good, arc outside edge in, chipped and flipped, chipped and slagged. Welded all flush, can't remember if he said 6011 or 6010. Built up flush, ground flush. Out of many welders taking test he got the job. Tensile strength of weld should be the same of parent metal. Or close.
    Flexibility because everything moves.

  • @haroldsprenkle4173
    @haroldsprenkle4173 3 วันที่ผ่านมา

    Hey my old hero Shaver told me one time weld it all the way through, it will be stronger that way. Then there are techniques to getting 100 % welds. No down hand passes, leave gaps, no constraint. Etc. Peheats, stress relief, in the end only the welder knows unless it has been xrayed.

  • @joemomma9177
    @joemomma9177 3 วันที่ผ่านมา

    Please, please send this video to the guy at asiawelder. He needs to figure out this concept. Lol😂 Excellent explanation

  • @tas32engineering
    @tas32engineering 5 วันที่ผ่านมา

    Showing how compound gearing works. The ratio's & change gears is not very well documented on video.
    Many have attempted it. But poor results.
    Denominator must be factorised.