# How tight is 6 Nm?



## Young Un (7 Apr 2009)

My carbon fibre seat post arrived today and I would like to fit it for tonights TT. However, in the instructions it says to only aplly 6 Nm to do it up, so how much is that?, I have got a torque wrench but it only goes down to 50nm and so isn't useful at all.

Cheers
Steve


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## ianrauk (7 Apr 2009)

Can't you set your torque wrench to the amount you need?

And don't you mean UP to 50nm?


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## Young Un (7 Apr 2009)

ianrauk said:


> Can't you set your torque wrench to the amount you need?
> 
> And don't you mean UP to 50nm?




No the torque wrench is a big one and only seems to deal with 50 Nm up to something like 200Nm.


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## Tynan (7 Apr 2009)

tee hhe, use a metre of wrench and hang .6Kg off it

I think, check the metre and the 0.6KG but you get the idea

I do my carbon seat post up as tight as I can with my multitool, it's never occured to me to worry about how tight


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## cisamcgu (7 Apr 2009)

Hmmmmm.... imagine a spanner 30cm long then if you hung two bags of sugar from the end of the spanner when the spanner was horizontal and attached to the bolt, that would be pretty close to 6Nm


Andrew


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## ianrauk (7 Apr 2009)

Oh I see, then you be needing a smaller one (states bleedin' obvious).


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## Young Un (7 Apr 2009)

ianrauk said:


> Oh I see, then you be needing a smaller one (states bleedin' obvious).




Yup I would, I might ask on my club forum to see if anyone has one that I could borrow before tonight


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## yello (7 Apr 2009)

6nm is bugger all. Go easy. 

Use the smallest spanner you can find (i.e. length, not bolt size!) and DO NOT heave it up tight. You'll have to go by feel but I reckon to aim for just as it bites/starts to stiffen and a just touch more.... but feel is everything here, do not be tempted to over-tighten.

It's a seat post so you'll be able to gauge very easily if it's too loose! Just gently does it until the post feels secure.

Edit: just dawned on me; seat post, it'll be a hex bolt in all likelihood. That's allen key territory. Same theory but you'll not need to be quite so gentle, allen key's flex a little so you'll be able to give that more beef. Surprised Tynan is brave enough to give it full welly but it's obviously ok!


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## MacB (7 Apr 2009)

if it cracks then you've gone too far.

Seriously, size of tool/length will make a difference, what feels like a lot of effort with a tiny allen key will feel like nothing with a longer lever arm.

I keep seeing the NM recommendations but have been loathe to spend ion a torque wrench. Going by feel at present, will probably break something at some point though


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## Crackle (7 Apr 2009)

About the same amount of force as between turning a tin opener and opening a jar of jam.


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## yello (7 Apr 2009)

Crackle said:


> About the same amount of force as between turning a tin opener and opening a jar of jam.



I wish I'd thought of that! Lovely description!


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## Gary D (7 Apr 2009)

Steve,

I have replied on the forum.

Gary.


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## Young Un (7 Apr 2009)

Pm sent on the other forum Gary


Steve


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## jimboalee (7 Apr 2009)

MacBludgeon said:


> if it cracks then you've gone too far.
> 
> *Seriously, size of tool/length will make a difference*, what feels like a lot of effort with a tiny allen key will feel like nothing with a longer lever arm.
> 
> I keep seeing the NM recommendations but have been loathe to spend ion a torque wrench. Going by feel at present, will probably break something at some point though



It how you use it.


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## jayce (7 Apr 2009)

Take your time as its not that tight i work with these tools every day


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## very-near (7 Apr 2009)

I have got a wrench which goes down that far. It cost me about £25-£30 IIRC.

The down side is that I don't have an allen key socket to fit it (1/4" drive)

If you are really worried about it, I might be able to wangle something, and get an old boy (was a local club rider) I work with who lives in Redditch ('greenlands' area ??? )to take it home with him one evening you could get off him - how big is the allen key ?


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## hubgearfreak (7 Apr 2009)

MacBludgeon said:


> if it cracks then you've gone too far.
> 
> Going by feel at present, will probably break something at some point though




then you can but a steel bicycle and go by feel. 

MacB..i think that yours is a steel bike. you'd need to be a gorilla to break it with normal handtools




Young Un said:


> No the torque wrench is a big one and only seems to deal with 50 Nm up to something like 200Nm.



that's not a torque wrench for cycling applications, give it to a car mechanic or farmer


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## Young Un (7 Apr 2009)

very-near said:


> I have got a wrench which goes down that far. It cost me about £25-£30 IIRC.
> 
> The down side is that I don't have an allen key socket to fit it (1/4" drive)
> 
> If you are really worried about it, I might be able to wangle something, and get an old boy (was a local club rider) I work with who lives in Redditch ('greenlands' area ??? )to take it home with him one evening you could get off him - how big is the allen key ?




Thanks very much for offering very-near, but I have now sorted it thanks to Gary 'legend' D.

Cheer for the advice guys.

Steve


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## youngoldbloke (7 Apr 2009)

Recommend torque wrenches from _PVR Direct_, Sealey, with calibration certificates. Most useful a STW1012, 2-24 Nm, (also AK623, 27.1 -108.5 Nm. for BB etc) Also Sealey S0533 Hex Bit & Holder set. Wrenches were about £25-30. Certificated kit - and they were discounted by more than 50% when I bought them. Best prices around at the time. relatively difficult to find 'light' torque wrenches anyway. The S0533 Hex bit and holder set is really worth having. 
(this posted in earlier threads)


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## palinurus (7 Apr 2009)

Young Un said:


> My carbon fibre seat post arrived today and I would like to fit it for tonights TT.



Good luck, hope the wind drops for you.


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## Young Un (7 Apr 2009)

palinurus said:


> Good luck, hope the wind drops for you.



Cheers, did a 27.05 for a ten which I am pretty pleased with considering there was a really big headwind for the first 5 miles. I also took a minute out of someone, who last week beat me by 5 seconds so oeverall I am pretty pleased.


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## Radius (7 Apr 2009)

Nice one Steve, I think I gots the same seatpost as you, which I also fitted today. Ended up racing (well, following, but it's more fun that way) a training TTer through Richmond park, after I made up a fair bit of ground (he was slow up the hills) we stayed the same distance apart for about 10 miles  I'll put it all down to the reduced weight of the post


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## 02GF74 (8 Apr 2009)

tighten it until it no longer slips and then 1/4 turn more.

as ^^^ say, too far and you start to see it crack. I had this on mine so to preven this, I pushed in a short piece of copper pipe inside the post to the area where the clamp is to prevent it crushing. Ok, so I gained a few grammes but was able to use the post and bling is more imiportant!


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