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lue
05-09-2010, 04:19 PM
does anyone know where i can get some heat treated hex cap bolt screws? i'm looking for the M8-1.25 metric bolts about a good 4inches long. i know there are some at local ace hardware and true value but i'm scare they might break off due to vibrations or some thing. i'm going to be using this bolt for adjusting the alternator in my celica.

Galcobar
05-09-2010, 09:36 PM
Make sure to get ones with a proper hardness number/shear strength and you should be good.

celicaturbo700
05-09-2010, 11:45 PM
^agreed

Galcobar
05-10-2010, 01:46 AM
I'm not sure, but I think Fastenal has stores in the U.S.

Grot
05-10-2010, 02:34 AM
An autoparts store should have the correct ones.

Im pretty sure mine sells them

klapa
05-10-2010, 03:07 AM
Best place to really KNOW what you are getting - is McMaster-Carr in Atlanta GA.

They will list not only hardness "grade" - e.g. "Grade 8" but also the actual material - e.g. "SST 440".

I buy metric hardware from them all the time for my business - you might be surprised to find how inexpensive they are compared with the "Home Depot" and Fastenal" of the world.

In fact - here locally we have a FastenAl right down the street - but they have nearly nil for metric hardware - especially the smaller machine screws that we frequently need.

Check out McMaster-Carr - they have a great website.

You might have to buy a package of fifty of smaller items like washers, etc. - yet you may find that this package will cost you twice what a package of four would cost from the other vendors.

lue
05-10-2010, 03:19 AM
Make sure to get ones with a proper hardness number/shear strength and you should be good.

how do i know which kind has a good or tough hardness to it? does it have a certain number to tell? sorry, i'm a noob at reading screws..

klapa
05-10-2010, 03:39 AM
They are "graded" by stength/harness - and at least for a hex-head bolt will have lines on the top to denote the rating.

These lines are just short lines - if there are none - then it is a "grade 1" - "lawn mower" quality soft steel that is good for general low strength fastening application where there is little to no actual stress.

If there are three of these lines then the bolt is grade 5 - most bolts are this for most applications except those that are subject to continuous thrust.

Five lines is Grade 8 - the best - the strongest. Like a flex-plate is bolted to a torque converter with Grade 8 - head bolts are Grade 8 - flywheel bolts - Grade 8.

Best thing to do is just get the Manf. P/n - then you won't need to guess.

lue
05-10-2010, 04:49 AM
They are "graded" by stength/harness - and at least for a hex-head bolt will have lines on the top to denote the rating.

These lines are just short lines - if there are none - then it is a "grade 1" - "lawn mower" quality soft steel that is good for general low strength fastening application where there is little to no actual stress.

If there are three of these lines then the bolt is grade 5 - most bolts are this for most applications except those that are subject to continuous thrust.

Five lines is Grade 8 - the best - the strongest. Like a flex-plate is bolted to a torque converter with Grade 8 - head bolts are Grade 8 - flywheel bolts - Grade 8.

Best thing to do is just get the Manf. P/n - then you won't need to guess.

i decided to go to truevalue today and buy some hex screws. it has a number 8.8 JH on top of the bolt. i don't know if that stands for the grade..??

Galcobar
05-10-2010, 05:21 AM
http://lmgtfy.com/?q=bolt+hardness+scale

lue
05-10-2010, 05:50 AM
http://lmgtfy.com/?q=bolt+hardness+scale

that was pretty kool how you did that..i guess 8.8 will do it then. =)

thanks for all the help guys. my dumb ass learned a lot from this forum.

celica9303
05-10-2010, 05:59 AM
EVERY BOLT I REPLACE ON MY CAR IS WITH A GRADE 8 overkill/ probably but i know they wont break