M3-M4 Rivnut and Bolts

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MTJ
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M3-M4 Rivnut and Bolts

Post by MTJ »

on FB it was mentioned that there is a wholesale change on these sizes.... yet I can't find it. ( just got my QB Tsi kit)

Was there a SB on this? Musta missed this.
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PhilipRueker
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Re: M3-M4 Rivunt and Bolts

Post by PhilipRueker »

What was meant was that generally speaking M3 rivnuts have been replaced by M4 rivnuts across the build.

Main reason being that M3's often strip the thread and so it's easier to just go up one size to M4.

As far as I know, all newer instructions now will only refer to use M4 rivnuts.
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permagray
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Re: M3-M4 Rivunt and Bolts

Post by permagray »

While this is true, some number of the parts will have been punched to the M3 size and you will need to enlarge the holes for M4 rivnuts. They have not yet updated the manual to explain this.
WmInce
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Re: M3-M4 Rivunt and Bolts

Post by WmInce »

permagray wrote: Tue Apr 28, 2020 9:24 am While this is true, some number of the parts will have been punched to the M3 size and you will need to enlarge the holes for M4 rivnuts. They have not yet updated the manual to explain this.
Perhaps a dumb question, but why isn't the factory just punching M4 holes there begin with?
Bill Ince
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PhilipRueker
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Re: M3-M4 Rivunt and Bolts

Post by PhilipRueker »

WmInce wrote: Tue Apr 28, 2020 11:14 am
permagray wrote: Tue Apr 28, 2020 9:24 am While this is true, some number of the parts will have been punched to the M3 size and you will need to enlarge the holes for M4 rivnuts. They have not yet updated the manual to explain this.
Perhaps a dumb question, but why isn't the factory just punching M4 holes there begin with?
I Imagine they may have already made some parts which were still done to the M3 plans and their automatic process won't easily let them remount a part to change the holes after the part is completed, so they let the builders do it (which is easy enough and allows you to make sure you get a perfect fit for the rivnuts).

As permagray said, I'd imagine newly manufactured parts will start coming out with M4 size holes in the future.
Building a Sling TSi in my Garage.
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