I recently came across a oneway wheel balancing system
for grinders with a 1/2" spindle. Unfortunately, the spindle
on my old Jet 6" grinder is a bit too short (1/8" or so).
I was thinking oneway I could make things work would be to
use thinner nuts on the ends of the spindle.
Another way would be to machine the ends of the flange pieces
down by about 0.160", which will still allow a 1" wide wheel
to be used.
What are the specs on those nuts?
I know one is RH- and one is LH-threaded, and I think both
are 1/2" diameter. I measured 12 threads per inch with my
(std) gauge, but the common course thread 1/2" nuts are 13 tpi.
The closest metric size would be M12x2.0, but again the
thread pitch is funny. Most M12 are 1.25, 1.5, or 1.75mm
per thread. Maybe it's 1.75 ?
Any one know this spec for sure and even better where I
might find a high grade, thinner, LH nut like this?
I could also machine the existing nuts thinner, but I'd
rather use a higher grade, thinner one.
Thanks for any suggestions.
The Chinese apparently looked in their old copy of Machinery's
Handbook and noted that 1/2-12 is a US standard size, and comes
before 1/2-13 in the list. They must have then assumed that because
it was listed first, it is the preferred thread. Otherwise there is no
explanation for them using that thread in so much of the equipment
they export to the US.
"Jeff Dantzler" wrote: (clip) I measured 12 threads per inch with my (std)
gauge, but the common course thread 1/2" nuts are 13 tpi.(clip)
The outboard spindle thread on my Jet woodlathe was 12 TPI, LH also. I
called Jet to find out whether they had a handwheel to fit, and the answer
was no. The guy in Customer Service also said he had no idea why they used
non-standard threads. I ended up using 13 pitch threads, and just ran it in
until it jammed. It is possible that if you split a nut with hacksaw, you
will get a thin nut that goes on kind of like a self-locking nut. It
doesn't really need a lot of holding power. It just needs to press the
One-way perforated disks against the sides of the wheel hard enough to
Regarding 1/2" x 12 TPI it may be that they decided to use british
whitworth thread which is 12 TPI. That may not be very common in the US
but still readily available in the UK. If you could actually check the
thread angle accurately and found it to be 55 degrees instead of 60 that
would confirm it. I suspect that would be a lot of trouble though.
Jeff Dantzler wrote:
I suspected something funny was afoot.
I'll go ahead and machine the flanges to get an extra 0.160".
The grinder is to be a dedicated tungsten grinder, so it will
never see any appreciable loading. If I can get the wheels
balanced, dressed, and attached, I'll be happy.
The design of the balancing flange / nut is such that
the wheel thickness does not make a difference, since
the grinder spindle nut bears on the ends of the flange.
If I used a thinner wheel, I could machine more off
Since I just spent good money on a pair of wheels, I'll
start out by machining off what I can and that should
get me where I need to be.
Oneway says spindle must be at least 1 7/8".
Mine are 1 3/4", but I can gain 0.160" easily, which