M8 to M6 thread reducer? Do they exist?

[Jamoi]

All hail the mighty VTR hive mind...

I have an M8 hole, but I want to use M6 bolts, do you know if a reducer exists?

I ordered a pack on eBay from a "UK seller" which looked perfect for the job, but turns out the seller is actually in China and this was last year and they never arrived.

Do they have a specific name I could search for within the UK?

Cheers all

[Jamoi]

*****Edit*****

I believe I've found a UK stockist, so if anyone else is interested, I'll update once they arrive.

[yellabell]

They look like a similar idea to a helicoil?
I've done it before to repair a knackered subframe but I used M8 grub screws drilled & tapped out to M6. You need to put a slot in the end to screw the m8 into place (or use the M6 and a locknut) and then a bit of blue loctite.

[Jamoi]

They look like a similar idea to a helicoil?
I've done it before to repair a knackered subframe but I used M8 grub screws drilled & tapped out to M6. You need to put a slot in the end to screw the m8 into place (or use the M6 and a locknut) and then a bit of blue loctite.

Hey Yellabell, yes similar idea to a helicoil, but hopefully more of a positive fixing.

I did contemplate drilling and tapping a bit of M8 threaded rod, but I only have basic plumbing tools rather that a pillar drill etc. I'd like to build up some workshop tools eventually. It would make this project much easier!

[yellabell]

If you need owt exotic, non standard or stuff you can't buy message me. If the boss isn't looking I can knock a few bits up on the lathe at work.

[Jamoi]

If you need owt exotic, non standard or stuff you can't buy message me. If the boss isn't looking I can knock a few bits up on the lathe at work.

Ooh thanks

[tony.mon]

It might be too thin to take much torque. The thread root for a m8 isn't far off the outside diameter of the M6 thread, if that makes sense.
You might consider drilling oversize, then using an M10 to M6 version.
Alternatively, get it welded up, then drill and tap as you require.

Where is the fixing, is it into steel or alloy, blind or into walled section, if walled, how thick?

[Jamoi]

It might be too thin to take much torque. The thread root for a m8 isn't far off the outside diameter of the M6 thread, if that makes sense.
You might consider drilling oversize, then using an M10 to M6 version.
Alternatively, get it welded up, then drill and tap as you require.

Where is the fixing, is it into steel or alloy, blind or into walled section, if walled, how thick?

Yeah I hear you, I wouldn't use them for anything substantial. But it's just a really convenient M8 threaded boss already in the subframe (I think they secured the pillion footrests/exhaust hangers on the original subframe), I want to secure a bit of seat fairing using an m6 bolt through a rubber lined top hat spacer. So, max 6nm.

[MickMick]

I have used Wurth inserts successfully inside a VW turbo as I had a sheared bolt inside the variable dump vain section. https://eshop.wurth.co.uk/Product-categ ... en/GB/GBP/
You can buy them on ebay/amazon etc.
Regards
Michael

[Jamoi]

Hi Micheal, thanks for the info and link. They're just what I'm looking for.

I have ordered something very similar, so if they fail to turn up I'll get on to these!

[MickMick]

No probs. Mine was the M6 down to M4 with hardened Steel hex bolt because of the heat and work purfect.