Randall,
Are you saying the bolt solution is superior to Nelson's additional taper pin,
or just as good and a
little easier?
In Nelson's additional taper pin he threads the small end and nyloc's it. Are
you saying the taper
pin and nyloc provides less clamping force than the straight bolt (with bolt
head -- No head on the
taper pin). I can imagine Nelson's taper pin may tighten throughout the cross
shaft w/o much
clamping force, but on the other hand if there's enough force in this system to
shear the original
pin, seems that the bolt's clamping force alone (w/o considering bolt's shaft)
would not provide
much force. I can't imagine the bolt clamping force deforming the fork enough
to "clamp" it to the
cross shaft with enough force to withstand the rotational shear forces
involved. Am I missing your
point?
I keep coming back to the Nelson's taper pin solution because I believe use of
the reamer will
correct any sloppiness in the hole I drill -- freehand. I have a large floor
model drill press but
the cast iron foot is broken. Probably not a bad idea to fix that. Maybe that
would solve this problem.
I had thought the original pin was hardened and would snap rather than bend.
TRF calls it "high
tensil steel". Moss describes it as "high strength". You're saying the pin is
soft and bends before
it breaks, thus the bolt to hole sloppiness makes no difference?
Thanks for the tip on the drill bits. Do you a Drill Doctor?
Don Malling
Randall wrote:
>>Nelson argues that unless the bolt is a press fit, it is too
>>sloppy and does not share the load of
>>the fork pin. First the fork pin snaps and then the load is
>>carried by the bolt. He makes the same
>>case for the roll pin because it's a spring.
>>
>>I take it you guys believe it doesn't matter in actual practice?
>>Seems like a reasonable line of
>>logic to me.
>
>
> Like James said, I believe that once the tapered pin starts to deform (which
> it will before it snaps, my broken one looked like a pretzel), the bolt will
> come into shear and so carry the load. The extra friction between the fork
> and shaft caused by the clamping force of the bolt will help, too. (In
> fact, that may be the most important part, since it keeps the pin from being
> bent back and forth.)
>
> Plus, with two points of shear plus the friction, the bolt is considerably
> stronger than the taper pin ... even if the pin breaks, the bolt will carry
> the load just fine.
>
> More importantly (to me), the tip came to me from Ken Gillanders at BFE, and
> Herman van den Akker does the same thing too. These guys do a lot of
> Triumphs, so they know from experience what works and what doesn't.
>
> However, I will admit that when I did my own, I used a drill press and a
> slightly undersize drill bit. The result was a hole that was a light press
> fit for the 1/4" Grade 8 bolt I used. Sorry, I don't recall offhand whether
> it was a "C" drill (.242") or "D" (.246"). You'll need to measure your bolt
> anyway.
>
> FWIW, Enco has a set of drills that includes all sizes A-Z, 1-60 and 1/16 to
> 1/2 by 1/64 (115 bits in all) for $30.
> http://www.use-enco.com/CGI/INPDFF?PMKANO=47&PMPAGE=68
>
> Randall
|