Quick-acting nut or screw clamps
Quick-acting nut or screw clamps
(OP)
I'm looking for a screw clamp or a bolt/nut assembly that can quickly be pushed in to place and then tightened (preferably in stainless steel). I found a screw clamp that does this at Carr Lane (BAR-LOK⢠Quick-Acting Screw Clamps on carrlane.com), but they don't have anything in stainless, and then I found a quick-threading nut at McMaster-Carr (P/N 98150A710), but they don't have it in stainless either, and I don't know how reliable these are (I'm not even sure exactly how they work). Does anyone know of something that would work? Also, does anyone know how the quick-threading nuts work, and how reliable they are?
Thanks a million!
Thanks a million!





RE: Quick-acting nut or screw clamps
RE: Quick-acting nut or screw clamps
RE: Quick-acting nut or screw clamps
The nut is extra deep. The threads are relieved as if you ran a 1xOD milling cutter right through the center of the nut at ~45 degrees to the axis. Which would be a decent way to make a few on short notice.
When the nut is seated, it engages the stud threads like two grooved 'hands' or half-nuts facing in opposite directions and displaced from each other along the stud axis by half the nut depth.
To disengage, back the nut off a couple turns, and then tilt it around an axis normal to the stud axis, and the nut can be freely withdrawn straight along the stud axis.
They're strong enough to use for tooling, and work great, with high strength studs. I don't think they can develop quite as much tension as a regular nut, because the radial force from the axially displaced thread halves applies a bending moment to the stud. If you're going to cinch 'em real tight, you need to check your studs for bending under that loading condition, which would not be present with regular nuts.
Mike Halloran
Pembroke Pines, FL, USA
RE: Quick-acting nut or screw clamps
Dennis
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RE: Quick-acting nut or screw clamps
RE: Quick-acting nut or screw clamps
In my experience, antiseize compounds do a good job of stopping galling. However the stainless grade and whether it's heat treated or not is important. 316 easily galls whereas a heat treated 400 series doesn't.