Adjustable Squares shootout..Starrett VS B&S, Mitutoyo and Chineseum - Printable Version +- Woodnet Forums (https://forums.woodnet.net) +-- Thread: Adjustable Squares shootout..Starrett VS B&S, Mitutoyo and Chineseum (/showthread.php?tid=7350411) |
RE: Adjustable Squares shootout..Starrett VS B&S, Mitutoyo and Chineseum - Timberwolf - 10-06-2019 (10-02-2019, 11:17 AM)adamcherubini Wrote: I may not have watched carefully enough. Did he think the Starrett blade was out of square? From what I could tell it was out of straight, very possibly due to wear. The hollow thru the center of the blade is the tell tale sign. The Chinese tool was essentially unused. So makes sense that it was straight. ,,,,,,,,,,,,,,,,,,,,,,,,,, but my layout tools are like family members to me. I could not agree more....Particularly the little guys and the really old ones... ...... RE: Adjustable Squares shootout..Starrett VS B&S, Mitutoyo and Chineseum - pprobus - 10-07-2019 (10-05-2019, 08:24 PM)Derek Cohen Wrote: Inside the head is a tiny clamp, and this runs against the groove in the rule, which is hardened steel (at least I want it to be hardened steel, of my knive blades will wear it prematurely). That little clamp not only needs to fit the groove to hold the rule square to the head, but it must resist wear itself. As soon as it becomes a sloppy fit, accuracy goes. While you are correct about everything else in your assessment, I do disagree with this, somewhat. If the fit becomes sloppy between the clamp and the groove, does not necessarily mean that accuracy is out the window. The clamp's purpose is to hold the rule against an accurate surface, which is the surface inside the groove that the rule sits in. As long as it can do that without allowing the rule to move accuracy should still be maintained. For ex. I assume the clamp is designed so that there's enough clamp "length" to apply the correct pressure on the rule to keep it from moving. As long as the wear is even and the full length or nearly the full length of the clamp is still in contact with the rule, accuracy should still be maintained. Now if the square was dropped and the clamp length was either reduced due to breakage or bending, then I would agree that there is a possibility that not enough pressure could be put on the rule and there could be movement which would greatly affect the accuracy. Paul RE: Adjustable Squares shootout..Starrett VS B&S, Mitutoyo and Chineseum - Derek Cohen - 10-07-2019 (10-07-2019, 06:52 AM)pprobus Wrote: While you are correct about everything else in your assessment, I do disagree with this, somewhat. If the fit becomes sloppy between the clamp and the groove, does not necessarily mean that accuracy is out the window. The clamp's purpose is to hold the rule against an accurate surface, which is the surface inside the groove that the rule sits in. As long as it can do that without allowing the rule to move accuracy should still be maintained. For ex. I assume the clamp is designed so that there's enough clamp "length" to apply the correct pressure on the rule to keep it from moving. As long as the wear is even and the full length or nearly the full length of the clamp is still in contact with the rule, accuracy should still be maintained. Now if the square was dropped and the clamp length was either reduced due to breakage or bending, then I would agree that there is a possibility that not enough pressure could be put on the rule and there could be movement which would greatly affect the accuracy. Paul, you are correct. It is not the clamp that wears but the base inside the head which the clamp pulls the rule onto. That wears. It wears faster if the metals of the head and the rule are different in their wear resistance. Generally, the cheaper combos use softish metals. Here is a video (it is to FWW mag): https://www.finewoodworking.com/2016/12/02/truing-combination-square Regards from Perth Derek RE: Adjustable Squares shootout..Starrett VS B&S, Mitutoyo and Chineseum - bandit571 - 10-07-2019 Got to checking one of my Combo squares, this morning... [attachment=21087] Defiance by Stanley, No. 122.....held a square (that I also checked) to the combo square... [attachment=21088] NO gaps, repeat, no gaps. End of one blade sits lower, is all ( can't hold both and the camera... ) same board as before, same jointed edge... [attachment=21089] Usually, I use a combo square to lay out a straight line for grooves and such to follow....where I can set a distance in from an edge... As long as I take care and not drop, or otherwise abuse it....it should stay this way. Instead of a groove that can wear....this has a slot. "Clamp" in a bit more robust.. Might just keep this around.... |