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bolt class
t.j. - 25/2/07 at 10:30 AM

Hi,

Can anyone tell me what class bolt are needed for sva in the brackets.

I planning m12 class 8.8. Or does it have to be 10.9 ?

Thxs!


flak monkey - 25/2/07 at 10:34 AM

8.8 is fine


DRC INDY 7 - 25/2/07 at 10:45 AM

I have 12.9 as supplied by MK


t.j. - 25/2/07 at 10:51 AM

quote:
Originally posted by DRC INDY 7
I have 12.9 as supplied by MK


12.9???????????????
looks like overkill to me.


DRC INDY 7 - 25/2/07 at 12:03 PM

For suspension on road vehicles they are between 10.9-12.9


flak monkey - 25/2/07 at 12:06 PM

8.8 grade bolts are fine for all the suspension bolts on a locost as they are horrendously over specced at M12 anyway.

If you are using M8 bolts for suspension pivots, then I would suggest 12.9 grade SHCS.


macnab - 25/2/07 at 01:47 PM

I use to fly flex wing microlights, the ones with handglider type wings. The wing is held on by just one rather small bolt! Which not surprisingly worried me a bit till I found out it was rated to 14 tons! Fine since the plane was only about 200kgs

I’m also sure I heard that there’s class of M8 bolt that can hold the weight of a 40ton locomotive!




[Edited on 25/2/07 by macnab]


flak monkey - 25/2/07 at 02:02 PM

A 12.9 M8 bolt will take 4.5tonnes to break in tension or 4 tonnes to yeild. Which works out at 2.5tonnes in single shear or 5 tonnes in double shear (as in locost suspension bolts)

An M12 8.8 bolt will take 5.5tonnes in tension before it yeilds, and 3.3tonnes in single shear and 6.6tonnes in double shear...

David