Why did John Deere convert to metric bolts?
And when they converted, why did they decide to put 13mm, 15mm, and 18mm heads on their bolts?
Before I came across the CTS II, the only time I had to use a 15mm was when it was actually a Whitworth bolt. And a lot of tool sets don't even have a 18mm.
Worse still, when you replace a bolt with one from a fastener supplier, it will have a different size head than the John Deere ones. JD M10 is 15mm, generic M10 is 16mm. Then when you get into nyloc nuts it gets worse. M10 nyloc is 17mm. M12 bolt head 18mm, M12 nyloc 19mm.
I thought the USA was still using UNC and UNF?
The 7720 was good, 5/16 bolts have 1/2 heads, 3/8 bolts have 9/16 heads, 1/2 bolts have 3/4 heads, wherever you buy them, you can substitute bolts and still be able to use the same size spanners. UNF/UNC nyloc nuts are the same size as the bolt heads too.
Does anybody know what they were thinking????????
And when they converted, why did they decide to put 13mm, 15mm, and 18mm heads on their bolts?
Before I came across the CTS II, the only time I had to use a 15mm was when it was actually a Whitworth bolt. And a lot of tool sets don't even have a 18mm.
Worse still, when you replace a bolt with one from a fastener supplier, it will have a different size head than the John Deere ones. JD M10 is 15mm, generic M10 is 16mm. Then when you get into nyloc nuts it gets worse. M10 nyloc is 17mm. M12 bolt head 18mm, M12 nyloc 19mm.
I thought the USA was still using UNC and UNF?
The 7720 was good, 5/16 bolts have 1/2 heads, 3/8 bolts have 9/16 heads, 1/2 bolts have 3/4 heads, wherever you buy them, you can substitute bolts and still be able to use the same size spanners. UNF/UNC nyloc nuts are the same size as the bolt heads too.
Does anybody know what they were thinking????????