I am new to the forum. Please forgive my lack of machining knowledge. I was given a small bench grinder, it starts and runs fine, very quiet. The problem is I am missing a left handed nut for the grinder in order to mount a grinding wheel. It has a 1/2 inch arbor, which I think is referring to the shaft that the grinding wheels mount to. The threads are not standard threads. Anyway, where would I get this nut, the grinder is useless without it. Any help would be most appreciative.
Follow along with the video below to see how to install our site as a web app on your home screen.
Note: This feature may not be available in some browsers.
Largest Manufacturing Technology Community on the Web
Stay Connected:
Bench grinder qustion
- Thread starter bmg88201
- Start date
- Replies 31
- Views 3,799
dalmatiangirl61
Diamond
- Joined
- Jan 31, 2011
- Location
- BFE Nevada/San Marcos Tx
Unless its a metric thread (is it chinesium) it should be a standard thread, Fastenal and Ace Hardware carry left hand thread nuts. If you insist it is not standard, we need to know diameter and threads per inch in order to figure out what it is.
D.Minnich
Cast Iron
- Joined
- Mar 30, 2021
- Location
- Cleveland area
I would just order it online. I just googled this. All you have to do is change it to your brand...and maybe throw in a model #...google should spit it out.
The grinder brand is Buffalo, yeah it’s Taiwanese. 3500 rpm, 1/4 hp, arbor size is 1/2 inch per the label, model HG-6A. I tried a standard 1/2 inch nut on the right hand side and it only screws on a couple of threads and stops. I tried to count threads per inch and came up with 14 since the threaded end is not an inch long, I counted threads for a half inch and doubled it. Thanks for the help, I’ll keep trying, worse case is keeping the wheel and buffing pads and file 13 the grinder.
michiganbuck
Diamond
- Joined
- Jun 28, 2012
- Location
- Mt Clemens, Michigan 48035
You can go to decent hardware and pick up a few nuts to try.
14 MM is .551 so a little larger than 1/2"
look to see if it is fine or course thread, try to see that the right nut goes on by hand turning.
With having the right-hand nut you might just try that at the store..and so know the left
14 MM is .551 so a little larger than 1/2"
look to see if it is fine or course thread, try to see that the right nut goes on by hand turning.
With having the right-hand nut you might just try that at the store..and so know the left
Joe Gwinn
Stainless
- Joined
- Nov 22, 2009
- Location
- Boston, MA area
What's closest is M12x1.75, which will just fill a 0.500" hole. Many hardware stores carry such nuts in RH thread, so could be used for testing.
EPAIII
Diamond
- Joined
- Nov 23, 2003
- Location
- Beaumont, TX, USA
You say it is 1/2" and about 14TPI. I am thinking it may be a fine thread. 1/2-13 is the standard size. A well stocked hardware store (ACE) should have them in both right and left hand threads.
You will probably spend more in gas getting there than the cost of couple of a few nuts.
You will probably spend more in gas getting there than the cost of couple of a few nuts.
Wow, great information. I will take all this information to heart and do some snooping at the hardware stores. And if I can’t order just one then I’ll get the smallest amount I can. I did notice that standard 1/2 inch bolt threads are finer than the arbor threads by a little. In my opinion, I would not consider the arbor threads to be classified as fine threads. Thanks for helping this dumb ole pipe welder out.
michiganbuck
Diamond
- Joined
- Jun 28, 2012
- Location
- Mt Clemens, Michigan 48035
You can rub a sharpie on the thread and then rub a slip of cardboard or even paper to make an eyeball thread pitch gauge.
Joe Gwinn
Stainless
- Joined
- Nov 22, 2009
- Location
- Boston, MA area
You may wish to acquire a thread pitch gauge. Here is one:
ChgImposs Metric & Imperial & US Screw Gauge SAE Whitworth 55 Degree & Metrisch 60 Degree Thread Pitch Gauge for Industrial Measurement: Amazon.com: Industrial & Scientific
tnmgcarbide
Diamond
- Joined
- Jul 6, 2004
- Location
- N. GA- 33.992N , -83.72W usa
if it's made in the country of Taiwan, and purports to have an 1/2" thread,
then i would say it probably is . 1/2-13 , 1/2-20 ... i'd say the 20 tpi is
likely.
the easy way here is to try the other side , w/ the right hand threads first. it will most likely be the opposite of the lh thread. a .50 cent
nut from the hardware store tells the truth...then buy what you need.
better still... take the nut to a REAL hardware store and see if they have a bolt that fits the rh nut.
that would be a good place to be .
then i would say it probably is . 1/2-13 , 1/2-20 ... i'd say the 20 tpi is
likely.
the easy way here is to try the other side , w/ the right hand threads first. it will most likely be the opposite of the lh thread. a .50 cent
nut from the hardware store tells the truth...then buy what you need.
better still... take the nut to a REAL hardware store and see if they have a bolt that fits the rh nut.
that would be a good place to be .
Buy a new one for $30 max.
Bill D
Diamond
- Joined
- Apr 1, 2004
- Location
- Modesto, CA USA
It may be Whitworth which is a British standard of 55 degrees instead of 60 degrees. Often found in Asia.
Bill D
Bill D
metalmagpie
Titanium
- Joined
- May 22, 2006
- Location
- Seattle
It's a left handed 1/2-20 nut. Order one from McMaster-Carr.
Sorry for the bother on a such a trivial matter. I took the RH nut to hardware store and it would not fit a metric bolt, it started a few threads on a 12mm bolt including 12mm 1.75, I tried both course and fine, no luck. I guess I’ll invest in a thread gauge, maybe that will lead to the right size. Thanks for everybody’s input.
bikebuilder
Stainless
- Joined
- Feb 26, 2007
- Location
- Montana
You don't need a thread gauge.
Go back to store and try it on standard threads. It will go I wager. They will have the correct lh nut at a place like ACE.
Go back to store and try it on standard threads. It will go I wager. They will have the correct lh nut at a place like ACE.
michiganbuck
Diamond
- Joined
- Jun 28, 2012
- Location
- Mt Clemens, Michigan 48035
Did you try it on imperial threads? like 1/2 13-20 and 28.
tnmgcarbide
Diamond
- Joined
- Jul 6, 2004
- Location
- N. GA- 33.992N , -83.72W usa
when does a grinder arbor be metric? i have many import bench/pedestal grinders,
and the threads are not metric . i hope you tried an english 1/2-20 first.
the wheels are standard, so a fucking 6" or 8" grinder should have an
english thread .
i have never, ever , seen a non standard thread on a bench grinder, angle
grinder , drill chuck arbor...sawzall set screw... if that machine is
that out of whack , throw it away and start over.
and the threads are not metric . i hope you tried an english 1/2-20 first.
the wheels are standard, so a fucking 6" or 8" grinder should have an
english thread .
i have never, ever , seen a non standard thread on a bench grinder, angle
grinder , drill chuck arbor...sawzall set screw... if that machine is
that out of whack , throw it away and start over.
Did you even look at that piece of shit? In 60 degree threads it does not have 13 or 20 TPI. What use would that be to the OP?
Similar threads
