Axle nut sizes
Hi Doc,
I feel pretty stupid asking this because I know your thread sizes post in the old forum - http://www.skatelogforum.com/forums/showpost.php?p=364629&postcount=1&fbclid=IwAR3wtt5nJ5EUmTZfbOlnWVQnJ1io6s2sC71Kjh9YtvpH1ACtFKY7J05JnD8 - but someone in a skate group is adamant that metric 7 mm nuts fit on her 7 mm Arius NTS plates (pretty much the first Arius that came out) and metric 8 mm nuts fit on her 8 mm Arius axles. Besides, a friend of mine has been able to put an 8 mm Roll-Line nut (our skate shop says they're M8) on her 8 mm Arius axles. So my question is: are they really interchangeable? Or are standard M7 and fine M8 nuts just so close to the US sizes that it's not immediately noticeable that they're different?
Comments
I have never seen any 7mm Arius trucks and I have a set of the original adjustable ones as illustrated in Dan Miller's original patent. Perhaps she meant a Bont Athena?? The very first ones were 7mm ( I had 2 sets originally) and use M7 nuts as do the Bont Infinity plates.
Metric 8mm nuts?? Which M8?? I see M8 nuts that range from 0.75 mm between threads to 2.5 mm between threads.
Putting them on?? Well I have seen "skate techs" put 3/8 x 16 course bolts into 3/8 x 20 plates. Now back to US "8mm" axles. They are 5/16" or 7.93mm, so obviously smaller than 8mm. So one can most likely force them on, but it is not an exact fit. I am to tired to do the math to tell what the difference is, but I can shoot some side by side pix to show what the differences are.
I seriously doubt the 9/32 x 32 TPI (American "7mm") nut will fit on a M7x1 axle with any degree of success. . The M7 axle thread is much courser. Those I can photograph as well.
They may be close but not close enough for me to want to do it.
Thanks for answering!
They're definitely "7 mm" Arius trucks that she got directly from Powerdyne. I've seen them but I don't think I can repost someone else's pics here 😞.
I think Roll-Line's M8 nuts must be fine M8, not the coarse pitch that's the standard here (1.25), but I have no idea what kind of fine pitch, 1.0 or 0.75. I think so, because my friend who has both Arius plates and Roll-Line 8 mm nuts there said a normal M8 nut didn't fit on those axles at all whereas the Roll-Line nut did.
Yeah, I didn't think M7 fit on US axles (and another friend has tested this with his Roll-Line and Labeda Proline nuts & axles and found they didn't fit), but I really wondered, because that person was so adamant that they did.
Pics to illustrate all this would be really cool, so please post some if it's not too much trouble.
By the way she's asked the Riedell rep for Europe and they claimed that the standardised M whatever size nuts fit on their Powerdyne axles - must have meant M8 because "8 mm" is all that Powerdyne usually have?!
might be slightly off topic but i have some boen lock nut trucks and those 7mm are not interchangeable with my other brand 7mm axels so 7mm isn't the same lol i thought the threads were Diff but i just learned in here it's the actual size
Wow, Boens with axle nuts? Are they the newer ones from that website?
And yes, if mine had axle nuts, those would be metric for sure!
Completely crazy thought: Is it conceivable at all that - seeing as they already deviated completely from what they usually do by making "7 mm" axles at all - Powerdyne put metric axles on their early Arius plates?
I really want top see the 7mm Arius axles. I have never seen PowerDyne do 7mm anything and I have had my hands on every (and owned several) PowerDyne plate made. Ya see Riedell only sells 8mm bearings so why would they make 7mm axles.
In fact I would love a pic of her plates. You can email me the pix thru the link in this form. I won't share them.
What link?!
OK, I can now answer part of this; Roll-Line 8 mm axles are ... wait for it ... imperial 😮. So there is an international standard, only it's the US one 😁.
This is the answer I got from Roll-Line when I asked:
"The thread of the 8mm axle is imperial 5/16’’
24 thread per inch."