Very Interesting "Bolt Science"

[Joe C.]

Here is what I found while researching the phenomenon of loosening header flange bolts.

http://www.boltscience.com/pages/vibloose.htm

Whiz-Lock is a registered trademark of the MacLean-Fogg Co

[Bill M.]

Re: Very Interesting "Bolt Science"

BE SURE TO CLICK ON THE VIDEO LINK AT THE BOTTOM OF THE PAPER.

Did I see no. of cycles = Hz. ?!

[Michael W.]

Re: Very Interesting "Bolt Science"

Did I see no. of cycles = Hz. ?!

Yes. In the test the bolt with the plain washer came loose in 300 cycles, with a spilt washer it came loose in 500. No surprise there. I learned long ago that washers, french locks, lock wire etc. does not stop a fastener from coming loose, it simply prevents it from falling apart completely. Sometimes.

[Dick W.]

Re: Very Interesting "Bolt Science"

Properly installed, safety wire works every time

[Joe C.]

Re: Very Interesting "Bolt Science"

Did I see no. of cycles = Hz. ?!

Yeah, I didn't understand that either. AFAIK, Hz = cycles/sec, not cycles.

Here's where I saw it first:

http://www.boltscience.com/index.htm

[Robert S.]

Re: Very Interesting "Bolt Science"

Seems to leave two choices for exhaust manifolds, french locks or Stage 8 bolts. So far, french locks have worked for me.

Bob

[Joe R.]

Re: Very Interesting "Bolt Science"

Yeah, I didn't understand that either. AFAIK, Hz = cycles/sec, not cycles.

Bill and Joe,

Technically, you are both correct (Hertz = cycles per second). But sometimes cycles is used informally as shorthand for cycles / second. E.G. 60 cycle power.

Joe

[Joe L.]

Re: Very Interesting "Bolt Science"

Here is what I found while researching the phenomenon of loosening header flange bolts.

http://www.boltscience.com/pages/vibloose.htm

Whiz-Lock is a registered trademark of the MacLean-Fogg Co

Joe------


I'm glad to see that they agree with my long-held opinion that split lockwashers are useless. If they had come to any other conclusion I would have questioned their credibility.

[Michael G.]

Re: Very Interesting "Bolt Science"

I'd be careful about extrapolating the results of Junkers tests to apply to all threaded joints. I think these folks have over-simplified it to the nth degree.

I do like their initials, though....

[Bill M.]

Re: Very Interesting "Bolt Science"

Bill and Joe,

Technically, you are both correct (Hertz = cycles per second). But sometimes cycles is used informally as shorthand for cycles / second. E.G. 60 cycle power.

Joe

Joe:

I think the abscissa is cycles, not cycles/sec...

Bill

[Joe R.]

Re: Very Interesting "Bolt Science"

Joe:

I think the abscissa is cycles, not cycles/sec...

Bill

Bill,

You lost me there. Did you mean numerator or denominator, or what? Cycles is unit less. Cycles per second means how many 360 degree cycles of a waveform (sine wave, square wave, etc) are there in one second.

Joe

[Charles F.]

Re: Very Interesting "Bolt Science"

Didn't know what "abcissa" was. Per Wikipedia:

The first of the two terms by which a point is referred to, in a system of fixed rectilinear coordinate (Cartesian coordinate) axes. The abscissa is also known as the "x" coordinate of a point, shown on the horizontal line, with the ordinate, also known as the "y" coordinate, shown on the vertical line.
The point (3,2) has 3 as its abscissa and 2 as its ordinate. Chuck

[Bill M.]

Re: Very Interesting "Bolt Science"

Bill,

You lost me there. Did you mean numerator or denominator, or what? Cycles is unit less. Cycles per second means how many 360 degree cycles of a waveform (sine wave, square wave, etc) are there in one second.

Joe

(Sorry, Joe. Too many math classes.)

I think the x-axis is cycles, not cycles/sec.

Bill

[Joe C.]

Re: Very Interesting "Bolt Science"

Didn't know what "abcissa" was. Per Wikipedia:

The first of the two terms by which a point is referred to, in a system of fixed rectilinear coordinate (Cartesian coordinate) axes. The abscissa is also known as the "x" coordinate of a point, shown on the horizontal line, with the ordinate, also known as the "y" coordinate, shown on the vertical line.
The point (3,2) has 3 as its abscissa and 2 as its ordinate. Chuck

Well done!
Now, name the three axes in solid geometry.

[Richard J.]

Re: Very Interesting "Bolt Science"

I've had a problem keeping the header bolts tight on my exhaust manifold. What to you call the washers shown at the 9 o'clock position on the blue background pic at the bottom of the page? (interlocking washers split the long way) Header company sold me a handful of those and I have them on the car now. Was curious as to the name of them.

Unfortunately, french clips wont work with my headers.