Gstan

Ok, I’m pretty sure son standard sizing. 1/4x20x 1 ½ means 1/4” thick, 20 threads per inch and 1 ½” long. Am I correct?
How about metric? My 4*40 has M3x20 nuts for a motor mount. Is M3 the thickness and thread size and 20 the length?
And what is the best place to purchase these?

DMcQuinn

My Feedback: (13)

you are correct about the sizing. bolts smaller than 1/4 inch use a numbering system. 4-40 6-32 8-32, etc. The smaller number is smaller diameter and the second number is the threads per inch. Sears hardware, ACE hardware, etc usually have these. But the smaller sizes are sometimes harder to find. small metric (e.g. 2 mm 3 mm etc) can be hard to buy locally. rtlfasteners, microfasteners sell them on line.

DavidAgar

My Feedback: (108)

You can also go to the local Ace Hardware store. They sell a varity of size bolts at mine. Good Luck, Dave