Smart Nuts

video Smart Nuts

These adjustable nuts are drilled and tapped so the nut will slide over any
length of threaded rod. The threads are engaged when tilted or tightened
again a stop. We use these in our shop for clamping stacks of paper for
padding and bookbinding. There is a video about hardcover bookbinding on our
YouTube channel showing one use for these nuts. They can be made from brass,
aluminum and steel, but we like hex pvc since it's very easy to machine and
quite inexpensive.

granthams (author) says: Jan 8, 2013. 1:19 AM

By keeping slight pressure on the drill quill downfeed lever, the
tap will 'thread' itself into the pvc nut. This is something I would not
try with a smaller tap or in metal due to the likelyhood of breaking the
tap. This drill press is also modified both with a forward/reverse switch
so the tap can be easily backed out. This drill press also has a shop
built socket with handwheel attahment on the quill pulley to tap by
hand so the tap can take small bites by working it back and forth
to clear chips, like you mention in your comment.

FYI screw machine drill bits with a 135 degree point are about the
same length as a tap and don't tend to walk like a 118 degree bit.

sleeping says: Jan 8, 2013. 12:26 AM

By the way how do you keep the TAP from "drilling" instead of tapping thread with the drill? I normally tap threads manually.

sleeping says: Jan 8, 2013. 12:23 AM

Thanks for great idea. Hope you keep the instructables, really good stuff.

granthams (author) says: Jan 7, 2013. 7:42 PM

That's right. The end mill is used to cut a clean path without threads so that when the nut is held at an angle, it will slide easily.The reason the nut needs to be an inch high is to have enough internal partial threads to grip the threaded rod.

bill z says: Jan 7, 2013. 7:19 PM

so the end mill removes the threads from the top inside and the bottom outside when it straightens out the remaining threads half on top and half on bottom hold the nut in place right

rimar2000 says: Jan 7, 2013. 5:25 PM

Very, very clever and useful. Thanks for sharing.

bill z says: Jan 7, 2013. 3:57 PM

well done sir now you need to get all the rest of those "projects" on here I'll get ahold of this weekend

embochner says: Jan 7, 2013. 11:05 AM

brilliant idea

granthams (author) says: Jan 7, 2013. 6:37 AM

The 3/8" end mill goes all the way thru, starting about 1/16" ahead of the tapped hole and exiting about 1/16" behind the tapped hole on the opposite side. An end mill should be used because it cuts it's own path, A twist drill bit tends to follow the threads and messes up the threads.

Lectric Wizard says: Jan 7, 2013. 6:05 AM

Are the entry & exit offsets on opposite sides of the nut ? How far do they go thru -( I assume over half way) ? A quick sketch would be nice. Thanks!