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I'm trying to find consensus for renaming "(mechanics)" pages, where "mechanics" refers to machinery, mechanisms, mechanical devices or mechanical engineering, rather than (e.g. classical) mechanics in physics and applied math. I would like to rename this page to something like "Wedge (mechanical device)". Any comments or objections? Geometry guy 20:41, 21 February 2007 (UTC)
I think it would be interesting to compare (1) mechanical-type wedges, and (2)"wedge-like human dynamics" in group settings. I suspect there would be many parallel's and think this should be better understood. Peace. Ken Hausle.
KenH 15:00, 19 August 2007 (Charlotte, NC)
What is the "Mrs. Prakhya" reference in the discussion of mechanical advantage? This does not seem to bear any relationship to the formula MA=S/T. -- Touretzky 06:38, 8 April 2007 (UTC)
I would say that is minor vandalism that a student from Tecumseh did. However, you did the right thing to change that back. LostNecromancer 19:49, 8 April 2007 (UTC)
The resultant forces we're interested in when calculating the mechanical advantage of a wedge are perpendicular to the applied force and thus to the length of the wedge, not perpendicular to the sloped sides of the wedge. Therefore, mechanical advantage for a wedge equals length divided by width, not length of slope divided by width (or "thickness" ??), as the article states. I.e., MA = L/W, not MA = S/W (or S/T ??). (MA for an inclined plane equals length of slope divided by height of slope, or MA = S/H.)
However, "In other words, divide the length of the wedge by its width" is correct.
Corrections made.
Cheers, Rico402 (talk) 17:58, 5 December 2008 (UTC)
Hi there! Well, it's not a "proof", but rather a mathematical method applicable only to a specific case (a "splitting wedge"), rather than the general case, where the desired direction of motion is perpendicular to the slope. (In any event, I think we've shown that supposed "authoritative" sources, i.e. the references, can disagree.)
Your other ref, the "Wedges and screws" article, is a poor choice, and very poorly placed within the article. It's a collection of diagrams principally devoted to friction vectors. No where does it say the wedge "functions by converting a force applied to its blunt end into forces perpendicular (normal) to its inclined surfaces", as your citation suggests.
I would also like to point out that if you alter the first diagram in "Wedges and screws" such that the red block has a rectangular cross-section, then since its motion is limited to vertical displacement and dependent on the horizontal displacement of the "half-wedge", and discounting friction, the applied horizontal force is translated entirely into a vertical force; and thus MA=L/W. This is how a "lifting wedge" functions.
Neither of my refs were "blog entries", and were entirely in keeping with Wiki guidelines. But, what's really needed here is a "force vector diagram", but I haven't the software to generate one. It would be helpful in describing "splitting wedges" vs. "lifting wedges".
But I do have another sound reference:
Others:
That's four solid references. I may be incomplete, but I'm certainly not "wrong".
Btw, I've restored the image of the splitting wedge showing the resultant forces perpendicular to its inclined surfaces. (Shame on you for not doing so. ;) Cheers, Rico402 (talk) 08:48, 13 September 2009 (UTC)
The point on lifting wedges vs splitting edges is important. I did some analysis of both types (complete derivations w/free-body diagrams and equations of static equilibrium), and it turns out that for a single/lifting wedge, the mechanical advantage = 1/tan(θ) = t/L, but for a double/splitting wedge, the mechanical advantage is 1/(2*tan(θ/2)) = L/t. In both examples, L is the length of the wedge (perpendicular to small side, which has length t). So, the statements about mechanical advantage are confusing as it stands, because although the overall L/t is correct in both cases, the rest of the results are not. 134.250.130.186 (talk) 19:42, 13 September 2021 (UTC)
(1) In woodworking, esp. greenwood working, a pair of wooden wedges are sometimes used to fill a gap (to holdfast a workpiece). In use, they are placed hypothenuse to hypothenuse and tapped until the fit is firm. There is a special name for this, which unfortunately escapes me now - it might be "FOLDING WEDGES" or "PARALLEL WEDGES". I think there used to be a wiki webpage on this use of a pair of wedges but I am unable to find it now without the name (but perhaps it was this: http://wiki.diyfaq.org.uk/index.php?title=Wedge ). It would be good to identify the correct name & link from here to that page (& vice versa).
Also, there is supposed to be an optimum angle for such wedges, which I am keen to discover. Suggestions I have come across so far are around: 4%/5-degrees/1:12/1:8/1:7/1:6 but I would be interested to see a definitive reference on this.
I also came across Quoin (printing), which is perhaps a special case of "folding wedges": https://en.wikipedia.org/wiki/Quoin_(printing)
The result of the move request was: consensus to move the pages at this time, per the discussion below. Dekimasuよ! 01:35, 10 May 2018 (UTC)
– in general, wedges mean this 209.52.88.26 (talk) 00:46, 4 May 2018 (UTC)