A Curiousity – Wood vs Metal Screws
flairwoodworks
| Posted in General Discussion on
Ever notice how all-wood handscrews are designed not to rack, but their modern-day counterparts can be angled quite a bit, while all-wood twin-screw vises can skew a lot, but metal twinscrew vises can rack very little, if at all? Odd.
Replies
Have you been racking your brain too much on that one, Chris? ;-)
He wooden do that to his metal capacity. It might rack it to much and screw it up.
Ever notice how all-wood handscrews are designed not to rack..
As in the design was intended or was it just that wooden screws have a very deep root comparied to a common metal thread for strength? Not sure I know, but a very good question that I will ponder upon.
You ask questions like my Son-In-Law askes me all the time. He is a Professor of early child education. Maybe he thinks I am a sort of gifted child or maybe just testing me for fun?? I have no idea....
Anyway, this Sunday he asked me about Lasers... I know something about them.. I have used them but NO EXPERT on the subject... He asked about Blue-Ray.. I stated that I am offering you information that I 'think' I know about them Lasers that I read about on http://en.wikipedia.org/wiki/Laser
I told him that I thought the designers loved the color Blue and the power needed would fit into the FCC (and other nations) regulations. I told him that as you go up in frequency, the ray is 'skinnier' and you can get more information (tracks) per given area of the medium.. He just looked at me really funny and then went away.... I think that I like the questions he gives me.. God help me if he thinks I am wrong....
Dunno
I don't know anything about wood handscrews, but I know that metal vise handscrews come in a few different flavors.
There are Acme threads, flat threads and one other kind that I forgot the name of, and they have different characteristics.
For instance, Acme threads will remain "tight" *(that is, with little lash) throughout their life, because of the taper in them, while flat threads will get looser and looser as they wear. There are many other differences, of course, but that's the one I can think of off the top of my head, because that's the one that mattered to me at the time I learned it. :)
So I suppose if you turned Acme style threads into your wooden handscrew, and then used it on a bench vise, you would have very little lash, but you would have racking problems. :)
It seems to me the female portion of the operation played some role in characteristics, but I didn't pay that much attention at the time, so I have no idea what that role is. :)
Chris,
Metal-screw handscrews are threaded into metal barrel nuts, that pivot in their beds in the jaws and allow for the angling of the jaws. Wood threaded handscrews are threaded directly into the wooden jaws, so there is little slack for angling the jaws.
Conversely, metal threaded vise screws are generally fixed to the moving jaw with a fairly snug collar or flange that is screwed or bolted to the jaw, allowing for little slack to skew the jaw. The wooden counterpart is generally slid thru an oversized hole in the moving jaw; the oversized head of the screw itself, not a flange, transfers the force to the jaw, allowing for more "slop", and ability to skew the jaw.
Ray
"allowing for more "slop", and ability to skew the jaw"
Ray, your comment prompted me to flash on my days of eating at the Army mess hall, where a lot of slop got past our skewed jaws. ;-)
Ralph,
Ah hope you'll 'skews me for mah sloppy syntax. Wha' jaw 'spect from a child of the South?
Ray
syntax and grammuh
(In your best Foghorn Leghorn voice) Ah have no problem with yohr syntax, son, or yohr grammuh. Ah do, howevuh have a problem with those Revenu'uhs and their sin taxes. ;-)
Ah Say, AH SAY!
Well, butter mah haid an call me a biscuit.
Them revenoor boys er 'bout as subtle as a hand grenade in a barrel o' mush.
Ray
This forum post is now archived. Commenting has been disabled