Funky small eye bolt threads

When I look at small eye bolt threads (not wood screw, machine screw)
I see thread sizes like 1/8"-32 and 3/32"-32 and 3/16"-24 in the
(e.g. McMaster-Carr page 1465.)
Is it possible that these are really 6-32, 8-32, and 10-24 threads,
just called something weird out of the deep eyebolt tradition? Or are
there truly funky threads with matching funky nuts only used on
I remember stove bolts coming in similar small fractional funky sizes
too but don't see them much anymore.
Reply to
Tim Shoppa
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A 10-24 nut fits the 3/16-24s from Home Depot just fine. Can't say for sure about the other two sizes.
We use them to hold mold-in inserts at my work, so I keep a small supply as well as a box of extra nuts. Each "insert holder" needs two nuts and I can tell no difference between the nut that comes with the eyebolt or the ones from the box.
Reply to
William Bagwell
(Catalog page actually has 5/32"-32, not 3/32"-32)
While 5/32"-32 and 3/16"-24 match up with #8-32 and #10-24, the diameter of 1/8"-32 would be like #5 (0.1250" basic diameter) rather than #6 (0.1380" basic diameter). Of course #5-32 isn't a standard thread, unlike #5-40 and 44.
I've seen #10-24 referred to as 3/16"-24, eg on boxes of stove bolts, but don't recall seeing 5/32"-32 before.
Reply to
James Waldby
Well... using the formula for diameter for number screws, I find that:
====================================================================== Katana:dnichols 22:57:27 > number-screw 5 32 For a #5-32.000 screw: Clearance diameter: 0.125 Tap drill diameter: 0.094 ======================================================================
So -- it is a number screw, but an uncommon one.
As for 3/32-32: (0.093" diameter)
====================================================================== Katana:dnichols 22:57:32 > number-screw 3 32 For a #3-32.000 screw: Clearance diameter: 0.099 Tap drill diameter: 0.068 Katana:dnichols 22:59:19 > number-screw 2 32 For a #2-32.000 screw: Clearance diameter: 0.086 Tap drill diameter: 0.055 ======================================================================
Neither of these match the diameter of the fractional size.
Same lack of match for a 3/16-24: (0.1875")
====================================================================== Katana:dnichols 23:01:41 > number-screw 10 24 For a #10-24.000 screw: Clearance diameter: 0.190 Tap drill diameter: 0.148 Katana:dnichols 23:01:47 > number-screw 9 24 For a #9-24.000 screw: Clearance diameter: 0.177 Tap drill diameter: 0.135 ======================================================================
It calculates to be just a bit loose.
Enjoy, DoN.
Reply to
DoN. Nichols
Thank you James.
I went to the local hardware store, bought some screw eyes of the various small sizes, and indeed 6-32, 8-32, and 10-24 seem to fit just fine.
Looking at my old machining books, I note that the nomenclature used for the screw eyes (3/16"-24, 5/32"-32, 1/8"-32) exactly matches the nomenclature for standard BSW and BSF threads. I think that's mostly coincidence, and I can tell by looking that these screw eyes were not cut with Whitworth thread forms. (Maybe not entirely coincidence because maybe our UNC/UNF threads were by design semi-compatible with BSW and BSF thread in parameters if not profile.)
Reply to
Tim Shoppa
The old US Sellers thread standards use pretty much the same pitches that Whitworth chose, except for 1/2-13 instead of 1/2-12.
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Jim Wilkins
Reply to
Jim Wilkins
Actually a lot loose! Grabbed one today and immediately noticed it is a rolled thread. Thought "ah-ha" and reached for my calipers, the un-threaded part of the eye bolt is only .158. Way under sized for 3/16 in my book.
Even the crests are a bit under 3/16 and the blame thing tapers five thou! .176 close to the tip to .181 near the eye. Apparently the root does not taper (nothing to measure it with here) as a nut is just as floppy at either end.
Bag of two eye bolts with two nuts and the plastic 'box' of 100 nuts are both distributed by Crown Bolt. No surprise why they fit the same... Nor was the country of origin;-)
Reply to
William Bagwell

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