1. This site uses cookies. By continuing to use this site, you are agreeing to our use of cookies. Learn More.
  2. Welcome To LandyZone!

    LandyZone is the biggest Land Rover forum on the net. We have plenty of very knowledgable members so if you have any questions about your Land Rover or just want to connect with other Landy owners, you're in the right place.

    Registering is free and easy just click here, we hope to see you on the forums soon!

High tensile bolts 8.8 v A2-70 stainless

Discussion in 'alt.fan.landrover' started by Simon Coupland, Jun 24, 2004.

  1. I have just swapped the bolts on my Safety Devices role cage for stainless
    (the old ones were rusty).

    I then got thinking whether they are strong enough.

    The original bolts are 8.8 grade and the stainless ones are A2-70.

    Anyone know if this is OK, or should I go back to 8.8 grade..?

    cheers

    simon

    --
    Simon Coupland
    Peak District, UK


     
  2. Simon Hi,

    I think that the best would be to ask SD themselves.
    But I think stainless steel has a tendency to crack under load while steel
    bolts warp and bend but do not break as easily.

    Please let us know since I would also like to replace the rusty bolts on my
    SD rollcages on both my Discos.

    Alternatively why don't you use cadmium plated bolts?

    Take care
    Pantelis


    "Simon Coupland" <someone@somewhere.com> wrote in message
    news:cbe0sc$l28$1$8300dec7@news.demon.co.uk...
    > I have just swapped the bolts on my Safety Devices role cage for stainless
    > (the old ones were rusty).
    >
    > I then got thinking whether they are strong enough.
    >
    > The original bolts are 8.8 grade and the stainless ones are A2-70.
    >
    > Anyone know if this is OK, or should I go back to 8.8 grade..?
    >
    > cheers
    >
    > simon
    >
    > --
    > Simon Coupland
    > Peak District, UK
    >
    >



     
  3. Pantelis,

    I have sent a mail to SD, so I'll pass on their comments. (I assume they'll
    say to revert to original spec as it would be a liability for them to say
    otherwise).

    I'll go to cad plated if that's the result of their comments.

    cheers

    simon

    --
    Simon Coupland
    Peak District, UK


    "Pantelis Giamarellos" <pantg@otenet.gr> wrote in message
    news:2jvh5rF15r6uuU1@uni-berlin.de...
    > Simon Hi,
    >
    > I think that the best would be to ask SD themselves.
    > But I think stainless steel has a tendency to crack under load while steel
    > bolts warp and bend but do not break as easily.
    >
    > Please let us know since I would also like to replace the rusty bolts on
    > my
    > SD rollcages on both my Discos.
    >
    > Alternatively why don't you use cadmium plated bolts?
    >
    > Take care
    > Pantelis
    >
    >
    > "Simon Coupland" <someone@somewhere.com> wrote in message
    > news:cbe0sc$l28$1$8300dec7@news.demon.co.uk...
    >> I have just swapped the bolts on my Safety Devices role cage for
    >> stainless
    >> (the old ones were rusty).
    >>
    >> I then got thinking whether they are strong enough.
    >>
    >> The original bolts are 8.8 grade and the stainless ones are A2-70.
    >>
    >> Anyone know if this is OK, or should I go back to 8.8 grade..?
    >>
    >> cheers
    >>
    >> simon
    >>
    >> --
    >> Simon Coupland
    >> Peak District, UK
    >>
    >>

    >
    >



     
  4. rads

    rads Guest

    On Thu, 24 Jun 2004 09:28:51 +0100, "Simon Coupland"
    <someone@somewhere.com> wrote:
    >
    >I'll go to cad plated if that's the result of their comments.
    >
    >cheers
    >
    >simon

    Cad plating is now almost obsolete. Cadmium is either carcinogenic, or
    poisonous, possibly both and definitely unpleasant.

    Zinc plating is more readily available.

    MAKE SURE bolts are de-embrittled after plating, otherwise heads can
    mysteriously fall off a couple of hours after you tightened them.

    David

     
  5. Wolverine

    Wolverine Guest

    Pantelis wrote:
    "But I think stainless steel has a tendency to crack under load while steel
    bolts warp and bend but do not break as easily."

    This is true. Stainless should not be used on areas of stress. It will snap,
    steel will bend.
    --
    Wolverine
    Big Red '93 110 CSW


     
  6. On or around Thu, 24 Jun 2004 08:46:11 +0100, "Simon Coupland"
    <someone@somewhere.com> enlightened us thusly:

    >I have just swapped the bolts on my Safety Devices role cage for stainless
    >(the old ones were rusty).
    >
    >I then got thinking whether they are strong enough.
    >
    >The original bolts are 8.8 grade and the stainless ones are A2-70.
    >
    >Anyone know if this is OK, or should I go back to 8.8 grade..?
    >


    we did this a while back. If you can get A2-80 then they're nearer
    8.8-spec. I doubt, however, that the strength of the bolt is that critical,
    A2-70 are pretty close to 8.8 - the toughest bolts I've seen were marked
    12.9, but I couldn't find any to replace 'em, and 8.8s in the same
    application never failed.

    Check with SD as was suggested, if you're not sure.

    Interesting to note that the specification for seat belt bolts (7/16"UNF) is
    designed to be OK even with mild steel bolts, which seems a sensible way to
    go - you can never know that someone will replace a bolt with the same spec.

    --
    Austin Shackles. www.ddol-las.fsnet.co.uk my opinions are just that
    0123456789112345678921234567893123456789412345678951234567896123456789712345
    1 weebl: What's this? | in recognition of the fun that is weebl and bob
    2 bob: it a SigRuler! | check out the weebl and bob archive:
    3 weebl: How Handy! | http://www.weebl.jolt.co.uk/archives.php
     
  7. kernowdragon

    kernowdragon New Member

    Joined:
    Apr 7, 2009
    Posts:
    1,878
    Likes Received:
    0
    Location:
    Wickford, Essex
    Long dead thread I know, but was searching for similar info myself and came across it, deciding it was an appropriate place to stick what I'd found......

    Where can I use A2-70 Stainless Steel bolts ?

    A2-70 can be safely used to hold car body panels and bumpers in place.
    Wing bolts, hinge bolts, handles, locks, light fittings etc.
    A2-70 can be safely used on non-mechanically loaded engine components where a clamping action is required.
    Manifold attachment, ancilliary attachment, pipe clamps, flanges etc.
    A2-70 can also be used for securing access panels, cover plates and accessory items to the vehicle.


    Where should I NOT use A2-70 Stainless Steel bolts ?


    A2-70 should not be used in heavily loaded mechanical or structural areas.
    • Areas of direct loading on the suspension.
    • Areas of direct loading on the steering column and linkages.
    • Active engine componets (con-rods, crank shaft, clutch & power off-takes)
    • Active gearbox and power-train components.
    A general rule of thumb is that it's OK to replace 8.8 and lower rated nuts and bolts.

    Any nut or bolt stamped with a 10:9 or 12:9 should be replaced with an identically rated (or higher) component AND NOT an A2-70 component.