10mm metric fine threads

[SmartWerks]

If its the strut mount bolts it will be 1.25 pitch, had enough Japanese cars to know. Get a pitch measure for feck sake

 

[ukracer]

Thanks mate. That helps but I also need to learn why I was confused

NOW I know why.

I have thread gauges but my son has the car.

THANKS AGAIN

 

[SmartWerks]

No worries, give us a shout as i have a fair few of them lying around. I'm currently breaking a t sport so have surplus for the cost of a stamp. Nice cars the 200's

 

[graffian]

Use bolts as pitch gauges. Grab an M6 or M8 and you can be fairly sure they are 1mm and 1.25m pitch.
You can measure it if you have a ruler, or caliper, get the threads clean and then roll a bit of paper round the
thread, it will leave nice marks and you can measure the pitch.

 

[SmartWerks]

Use bolts as pitch gauges. Grab an M6 or M8 and you can be fairly sure they are 1mm and 1.25m pitch.
You can measure it if you have a ruler, or caliper, get the threads clean and then roll a bit of paper round the
thread, it will leave nice marks and you can measure the pitch.

Nowt like over complicating a job a tuppence tool will do which we all should own?

 

[Pete.]

M10 x 1.25 and M10 x 1.0 are both fine threads. 1.0 is easy to check it's spark plug size for NGK plugs starting with C

 

[premmington]

This has been a problem at our workshop of late. I have even bought a thread pitch gauge to measure threads for special bolts.

I used to used a thread pitch file for the job.

 

[Tigman]

measure the nut and work out the TPI ( threads per inch ) then you will know what the thread is !

 

[normspanners]

Seat belt mounts

Careful on that one most seat belt mounts are 7/16 unf even on japs and they will screw into metric fine
I had that on evo9 somebody used seat belt bolts to mount suspension,
and they ripped out

 

[Rocketman]

WARNING you need to know what strength grade that nut is before replacing it with a new one.

I will more or less guarantee it's not 8.8 or they wouldn't have used a fine thread in the first place. It could well be 12.9 and will take considerably more load than a 8.8.

 

[Maker]

WARNING you need to know what strength grade that nut is before replacing it with a new one.

I will more or less guarantee it's not 8.8 or they wouldn't have used a fine thread in the first place. It could well be 12.9 and will take considerably more load than a 8.8.

So that's what the 8.8 is on the head of bolts. Is it tensile strength - 8.8 : 88,000 PSI?

 

[ford34/2]

Metric bolts

8.8
Class 8.8
Medium Carbon Steel, Quenched and Tempered

All Sizes below 16mm
580 Proof Load MPa
640 Min Yield Strength MPa
800 Min Tensile strength MPa

16mm - 72mm 600 660 830

10.9
Class 10.9
Alloy Steel, Quenched and Tempered

5mm - 100mm
830
940
1040

12.9
Class 12.9
Alloy Steel, Quenched and Tempered

1.6mm - 100mm
970
1100
1220

Stainless markings vary. Most stainless is non-magnetic.

Usually stamped A-2

A-2 Stainless
Steel alloy with 17- 19% Chromium and 8-13% Nickel

All Sizes thru 20mm
210 Min.
450 Typical. Yield Strength MPa

500 Min.
700 Typical. Min tensile strength MPa

Tensile Strength: The maximum load in tension (pulling apart) which a material can withstand before breaking or fracturing.

Yield Strength: The maximum load at which a material exhibits a specific permanent deformation

Proof Load: An axial tensile load which the product must withstand without evidence of any permanent set.

1MPa = 1N/mm2 = 145 pounds/inch2

 

[mike os]

check the thread carefully... metric fine comes in with 0.75,1.0,1.25 pitch varieties... just to keep it interesting...

 

[premmington]

Metric bolts

8.8
Class 8.8
Medium Carbon Steel, Quenched and Tempered

All Sizes below 16mm
580 Proof Load MPa
640 Min Yield Strength MPa
800 Min Tensile strength MPa

16mm - 72mm 600 660 830

10.9
Class 10.9
Alloy Steel, Quenched and Tempered

5mm - 100mm
830
940
1040

12.9
Class 12.9
Alloy Steel, Quenched and Tempered

1.6mm - 100mm
970
1100
1220

Stainless markings vary. Most stainless is non-magnetic.

Usually stamped A-2

A-2 Stainless
Steel alloy with 17- 19% Chromium and 8-13% Nickel

All Sizes thru 20mm
210 Min.
450 Typical. Yield Strength MPa

500 Min.
700 Typical. Min tensile strength MPa

Tensile Strength: The maximum load in tension (pulling apart) which a material can withstand before breaking or fracturing.

Yield Strength: The maximum load at which a material exhibits a specific permanent deformation

Proof Load: An axial tensile load which the product must withstand without evidence of any permanent set.

1MPa = 1N/mm2 = 145 pounds/inch2

Good info!

 

[normspanners]

M10 x 1.25 and M10 x 1.0 are both fine threads.

As Pete says 10mm thread X standard is 1.5, standard fine is 1.25, fine is 1.00, super fine .75 (not common).
Bilstein shocker top nuts old ones where 1.0 newer ones are 1.25
I allways have 1.5 to 1.0 in stock and taps etc for this reason.

 

[Rocketman]

So that's what the 8.8 is on the head of bolts. Is it tensile strength - 8.8 : 88,000 PSI?

Correct, well it's the tensile strength as shown by Ford34/2. On nuts it is often harder to see but you can usually see a small number 8 or 10 or 12 - if you can't don't buy/use them as they will probably be monkey metal.

So when replacing bolts on anything always replace with at least the same tensile strength.

BTW Halfords sell nothing higher than 8.8 and some are the totally useless 4.4 which I would not advise to use on anything on a car.

Just took the front wishbone off my car and even though the bolt was rusty you could still see the 10.9 mark. So the nut needs to be the same.

Cap heads on injection mould tools we usually use 12.9 or 10.9 min.

 

[ukracer]

check the thread carefully... metric fine comes in with 0.75,1.0,1.25 pitch varieties... just to keep it interesting...

Add to that 1.5 which I think is what we all have hundreds of.. Lol and it gets confusing.

 

[Maker]

the totally useless 4.4 which I would not advise to use on anything on a car.

FWIW, my dad had a gib key puller that specifically came with low tensile bolts so the bolts would snap before the head of the key does.

 

[Robotstar5]

FWIW, my dad had a gib key puller that specifically came with low tensile bolts so the bolts would snap before the head of the key does.

Similar, we had shear bolts in the transfer lines at Longbridge so the brackets would "snap" off instead of causing damage.

 

[Maker]

It didn't work though, the head of the key shot off and buried itself in the OSB lining in the shed. We ended up using a big puller to pull the whole flywheel off with the key in place, it got a hairline crack though because the key wouldn't budge.