Re: was Re: Weepy Head Gskt Fix!is stretch bolt defence clamping methods,

[Avi <Avi@cosmoslink.net>]

Mik, you are a good man....
see Kevin's post on the subject, good information.
As for removing the studs, I knew you had to remove the studs..... no other
way possible....as to the methods of removing a stud, that's not too big a
deal so long as they are not frozen in place!!!!!!!. 
My last comment(last question)is: if you are not using the studs "as studs"
meaning a natural alignment, why not use bolts (raceware, if you
want)?.....here is my version (of answer), bolts are much more costly to
make (in small quantity and from special material which i presume the
raceware hardware is), so it is "STUDS", i am also guessing (never saw
one), that the raceware hardware (threads) "is cut not rolled as the OEM
factory is?........ 

Nice chatting with you,

Avi

BTW, did you "really" know that stretch bolts (on heavy duty application)
are installed via a portable hydraulic press?...... the press is put on the
stud (not bolt), stretch the stud and you put on the nut finger tight, you
release the press and "voila" perfect torque..... 



>That or the old trick, of using two nut's tightned against each other!
>
>Some even "slot" the end of the stud
>
>                            Mik
>
>-----Original Message-----
>From: Avi <Avi@cosmoslink.net>
>To: Mik Tip <miktip@worldnet.att.net>
>Cc: quattro@coimbra.ans.net <quattro@coimbra.ans.net>
>Date: Saturday, December 27, 1997 1:23 PM
>Subject: was Re: Weepy Head Gskt Fix!is stretch bolt defence clamping
>methods,
>
>
>>Mik,
>>stretch bolts are used in HEAVY DUTY engines the ones that cost $500,000
>>(and more) AN ENGINE.........including some small ships engines........the
>>stretch bolts are installed with an hydraulic set-up...(and they get
>reused).
>>(in essence all threaded fasteners are a VARIATION of so called "stretch
>>bolts" including your "Raceware"), the difference in your OEM "stretch
>>bolts" is that the bolt is taken a lot closer to the yield point, in other
>>words using it to the MAX, that is also the reason why they are not
>>recommanded for REUSE, since they (the bolts) might be too close to the
>>yield point (after the first use), BTW, you can reuse OEM stretch bolts but
>>you MUST measure the bolt to find out if it did not exceed the yield point.
>>
>>"The highest possible clamping forces with very small variations can be
>>achieved with threaded fasteners using the angular tightening method and
>>the yield point controlled tightening method" (from automotive engineering
>>handbook).
>>
>>Avi
>>one of this days you might tell me how you can pull a head STRAIGHT-UP from
>>a VW 4cyl without taking the "studs" off......(engine in car...)
>>
>>
>>>As for the "stretch-bolts" being "BEST" there more in line with
>>>"Least costly for manufacturer" category!
>>
>>
>
>