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But Mad North-Northwest
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I believe the original photo identifies this as a DIN 6921 class 90 fastener.
Fastenal and others carry these.
Well I learned something today:

"These self-locking hexagon flange bolts are designated property class '90' or '100'. The flange bolts are case hardened in order to perform their self-locking function, and therefore cannot be classified as property class 9.8 or 10.9, although their tensile strength is at least 900 resp.1040 MPa."

Looks like the torque spec for an M8 class 90 bolt is 34Nm, or 25 ft-lb.
 

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Discussion Starter #22
I believe the original photo identifies this as a DIN 6921 class 90 fastener.
Fastenal and others carry these.
Thank you!

I called Fastenal and they do carry them. Should be here in a couple days.

How did you know that these were DIN 6921? I can guess how you knew the class 90 but not the DIN.

Would love to learn.

Thank you again,

Vin
 

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Thank you!

I called Fastenal and they do carry them. Should be here in a couple days.

How did you know that these were DIN 6921? I can guess how you knew the class 90 but not the DIN.

Would love to learn.

Thank you again,

Vin
Vin,
The pic you posted showed it to be a Verbus sourced part, and the non ISO marking of 90 puzzled me, so I tried a search for DIN class
Once the din standard number popped up, it became easy to look for a source.
Joe
 

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great pick up on that bolt symbol as belonging....sort of....to verbus, Joe!

In fact the symbol on Vin's bolt head is 'Bauer & Schaurte'
which I should have got, as the old factory is not even that far from me!
bauer1.jpg

and here the connection
verbus.jpg

DIN 6921 probably just stands for a 'flanged' bolt.

oh and don't go for DIN 6921S btw (thinking aha, the 'S' must mean for 'super' strength)....the S is a 'serrated' flange...so not what you want;)
 

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Discussion Starter #25
This group is amazing!

Vin
 

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Vin,
The pic you posted showed it to be a Verbus sourced part, and the non ISO marking of 90 puzzled me, so I tried a search for DIN class
Once the din standard number popped up, it became easy to look for a source.
Joe
Good eye and useful information. Thanks.
 

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Discussion Starter #28
Vin,
You may consider giving up your membership at the gym!!
And I need to get my glasses prescription checked as well 😄

Vin
 

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Discussion Starter #29
Hello All,

Wanted to complete the thread and provide some future guidance.

The description of DIN 6921S class 90 is in fact correct.

As you can see, the bolt on the left is the original which is serrated. The bolt on the right is the replacement I ordered from Fastenal, part number 0161881. M8-1.25 x 20mm, also serrated.

The Fastenal replacement is about 1.5mm shorter, but I do not think that matters.

LSD put together using 24ft/lbs torque on these bolts.

IMG_5155.jpg

IMG_5157.jpg


As always, thank you to all who helped.

Sincerely,

Vin
 

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Thanks for the follow up Vin!
And there was me saying you don’t want the 6291S as it would be serrated !
Live n learn👍
 
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