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    What do you use to determine beam size needed?

    You raise a good point about coming up with a cost-effective design. I've designed a lot of lifting devices, termed under-hook appliances in the business, and I adjusted the safety factor to suit the application and the circumstances of usage. First of course was to determine the legal safety...
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    What do you use to determine beam size needed?

    Notice that I wrote what the engineer would say, not what an actual beam might measure. There can be a big difference because as-rolled dimensions can be all over the map. The dimensions listed in the beam tables are the minimum dimensions and properties the beam must meet, eg. a W16x50 has a...
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    What do you use to determine beam size needed?

    I doubt very much that the engineer you referred to said such a thing! 1) There ain't such an animal as a commercial sized "seventeen" inch beam. The nearest is 18". 2) There are 15 different weights of 18 inch I-beams ranging in section modulus from 221 inch-cubed to 57.9 inch-cubed. 3)...
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    Keeping silver soldering flux usable

    Much good advice here; I like the one about storing the flux container in a glass jar with a little water in the jar. When mixing water directly with the flux I would caution you to use distilled water as the minerals in tap water will impede the flow of the solder in lap joints. For high...
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    OT: Trying to start an Engineering Group in Minnesota, USA

    Well, there are engineer's meetings and ENGINEER'S MEETINGS! I'm the past secretary \ treasurer of the ancient and honourable Grand Valley Group of Engineers now in its 93rd year of functioning. We currently meet in my city of Cambridge, one hour's drive west of Toronto. In the past (before...
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    Ideas for ID holding of 4" OD tubing with variable wall thicknesses

    If you do a lot of this kind of work I'd consider a 3 inch OD 3 jaw chuck. Put the outside jaws into the chuck and clamp on a dowel pin. Then check the concentricity of the OD of the jaws. If acceptable you are good to go. Simply slip the tube over the chuck jaws so that the chuck key may...
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    Question: Generally recognized rule of thumb for selecting appropriate metric units?

    "Metric Ton" is an Americanism ... sorry Americanizm. Everywhere else in the world, 1000 kg is a Tonne. Perhaps so. Much metrication is used in the USA too but the unwashed masses don't know and don't care. But my point regarding mega grams is valid especially in meetings and telephone...
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    Question: Generally recognized rule of thumb for selecting appropriate metric units?

    From my father's training manuals eons ago, the rule of thumb in the metalworking racket was to use mm. The rationale was that shop drawings accumulate smudges, grease spots, spatter marks, fly specks etc. that might be confused for decimal points or commas. But I agree that the choice is the...
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    Bolts Vs. Pins

    I sure hope that you don't design structures, because the bolted joints would not be in compliance with the building code when using the above criterion! A structural bolt has a maximum allowable shear stress and a maximum allowable tensile stress, the magnitude of each depending on the grade...
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    Bolts Vs. Pins

    What about bolts that "see" tensile and shear stress simultaneously? How much stress of each could a bolt carry simultaneously? Fact is, a bolt or pin in a clevis application, even a close-fitting clevis, sees shear and bending stresses simultaneously under load due to the edge deformation of...
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    Cut Threads that are the as strong as a rolled thread

    In the structural steel business A325 and A490 bolts are used to hold together bridges and building frames. Properly designed joints, along with proper torquing of all bolts, produces a joint system that is fatigue resistant. To achieve this, the bolting material is chosen so that the nut is...
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    Heat Treat Assistance needed!

    Induction hardening (really induction heating) is a method of heating conductive work pieces by electro-magnetic means. In essence the work piece is the short-circuited secondary winding of a transformer. Look this up on Youtube as "induction heating" or DIY induction heating. There is a lot...
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    Slightly OT - Resistance welding rings

    In my past, say 15 or so years ago, my employer purchased a length of chain from a manufacturer in the Netherlands. This manufacturer, with his quotation, sent a video tape covering the manufacturing process of this chain; the individual links were welded electrically, using a process very...
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    So what do you do for a living

    Of course they are stale, I'm an old guy. And they are supposed to be irritating to those that have no business inquiring what I do. I fact, the quip "as little as possible" is well received by people that know my profession. Arminius
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    So what do you do for a living

    "What do you do for a living?" Depending on the circumstances I would reply with one of the following, or a variant thereof: 1) As little as possible... 2) Anything for a buck... 3) I'm her (pointing at wife) kept man. Arminius
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    Making an oddball circular slide rule

    Somewhat off topic and not contributing to the question posed but, I post it for completeness regarding slide rules. In the early 1960's I had a summer job working in a civil engineering soils and aggregate lab. The engineer I worked for had a circular slide rule 10'' to 12'' diameter with a...
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    Homemade lapping compound

    Job/work piece description would be helpful... If you are lapping a soft material you may wish to use a lapping compound that breaks down with use, so as not to continue lapping... Bon Ami cleanser springs to mind. Arminius
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    Question about large metal contruction pin tolerance

    If it is for hoisting or lifting, ie. crane work, .75 mm diametral clearance is the way to go. If the working environment is rough or very difficult, double that to 1.5 mm on the dia. Best method: consult the design engineer whose name and seal should be on the drawing. Arminius
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    OT - Looking for an online engineering degree

    To the OP: You want to think very seriously what it is you wish to achieve. Do you want to become a licensed professional engineer, P.E. or P.Eng. designation? If so then you may wish to talk to your state licensing board first. They can advise you what courses are mandatory. My personal...
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    Shallow blind tapped hole

    I've done the following with a shallow, full-depth thread 5-40UNC hole. Drilled as required for 5-40 and then tapped using a 4-40 bottoming tap. Then went and re-tapped using 5-40 bottoming tap. Worked remarkably well in the bearing bronze work piece. The OP solved his problem with thread...