Bolt supply?

[HairyScreech]

I have just been trying to get some M12x1.5 10.9 grade bolts and can't seem to find any for love nor money.

Anyone know a source for some? I need some slightly longer ones for the calliper brackets so they have to be 10.9

40mm ideally but happy to cut some down.

It seems everywhere only has 1.75mm pitch or 1.25mm pitch and the E30 calliper bolts are 1.5mm pitch.

[DanThe]

Loads on ebay, I use cap screws from a local supplier

[HairyScreech]

I tried Egay. Maybe I somehow fudged the search, couldn't find 10.9s on there.

Edit - bugger it, gone for 12.9 cap heads for now, will hunt down the correct M12x1.5 10.9 hex head bolts later.

What do you torque them to Dan?

[DanThe]

FT

[HairyScreech]

Animal.

[DanThe]

With a 3/8 ratchet and experienced hand control/feel its not going to kill any threads

[maxfield]

With a 3/8 ratchet and experienced hand control/feel its not going to kill any threads

Or 2 ratatats on the buzz gun I'd you're a fitter

[hennared323i]

Do not over torque 12.9's

Different application I know but we replaced some 1 1/2" WW 10.9's with 12.9's and torqued them up to the same values....when the squeeze came on the bolt heads started firing off like bullets.

12.9's have a smaller plastic limit than 10.9's so less tolerant of over stressing

[DanThe]

Indeed, the higher the number the more brittle the bolt is, what was the application out of interest?

[hennared323i]

Holding a tunnel boring machine trailing shield in a fixed position.

When the driver got the machine geometricaly screwed up the friction generated by the lining binding on the inside of the shield and the ground binding on the outside was enough to split a few welds and pop a few bolt heads off.

Interesting times

[DanThe]

Cool, sounds like the 12.9 bolts would be much happier holding the brake caliper on an E30

[hennared323i]

Pic of cracked gusset and non sheared bolt heads (good side):



Pic of remedials after failure - big bit of steel and much welding:

[hennared323i]

Cool, sounds like the 12.9 bolts would be much happier holding the brake caliper on an E30

I expect they would

[HairyScreech]

So quick check says 110-125Nm for a 12.9 M12.

(= 80-90lbft)

[hennared323i]

I have just been trying to get some M12x1.5 10.9 grade bolts and can't seem to find any for love nor money.

Anyone know a source for some? I need some slightly longer ones for the calliper brackets so they have to be 10.9

40mm ideally but happy to cut some down.

It seems everywhere only has 1.75mm pitch or 1.25mm pitch and the E30 calliper bolts are 1.5mm pitch.

These any good?

http://www.margnor-online.co.uk/167m12x1-5px40.html

[HairyScreech]

That looks like the buggers.

Will have to save that link and put some on order.

[DanThe]

No shoulder on that, which will weaken it to a degree if your being fussy. Id rather use a 12.9 with a shoulder, helps centre the bracket/caliper too which is why you find lots of automotive bolts have non standard shoulder lengths/diameters

[hennared323i]

http://www.margnor-online.co.uk/168md12x50.html

These then and buzz 10mm off the thread

[DanThe]

[HairyScreech]

I don't think the bolts I took out were shouldered (or shanked if your like) will check when I fit the callipers.

Your right the shear strength is increased by shank bolts but only in the shanked section. Tensile strength is purely a smallest cross section thing so does not change.

For the 10.9 your looking at 90-110Nm.

[suedenim]

Used to order from this company for architectural metalwork applications. Plenty of tech data on their site too.

http://www.vjtechnology.com/

[mikelat]

I get all my special bolts/nuts through aircraft supply outlets as they have lots of high spec stuff and at reasonable prices.