Rivnut success

[Lindsay Rowland]

This may not be a big deal for the 'old man and the bicycle' types, but I've just had my first
encounter with rivnuts and finally won. I needed to fit water bottle mounts on a frame I've set up
as a fixed wheeler.

In this small town, the places you'd expect a chance of buying a couple of 5mm rivnuts were
disappointing. I may as well have been speaking Urdu or Fon. Rivnut is a great trigger for 'Huh?'.

I finally located some at the local aircraft maintenance hanger for $1 each. For all intents and
purposes aircraft bits and pieces are AF or non-metric. I wasn't deterred and as it turns out 3/16
fine thread is so close to 5mm x .8 (most water bottle screws) that they're as good as
interchangeable.

After carefully measuring and drilling the frame, it was time to wrangle with the rivnuts. I'd
assumed it was just a matter of putting the rivnut in the hole and then tightening a water bottle
bolt to expand the 'riv' part of the device. Nope. It took a bit of fussing around to locate a
longer 5mm bolt, nut and a piece of flat plate with a hole the right size. The device went: bolt,
8mm spanner, nut, washer, flat plate, rivnut. Then it was down to carefully tightening the nut with
the rivnut inserted in the frame. I made a point of greasing the washer under the nut so that it
could spin easily. It was then a matter of feeling when the resistance slightly increased then
stopping. The rivnuts are aluminium so it would be very easy to strip the threads.

In my searching earlier I came across a rivnut kit with assorted sizes and a pop rivet plyers -
$160! Sure the plyers would have made the insertion a whole lot easier, but without them I had a
very intimate learning experience. And I'm quite chuffed to have water bottle mounts where they
weren't previously and it only cost $2.

So if anyone is thinking about fitting water bottle mounts to a bike I can vouch that is quite
straight forward and they should have the confidence to take the job on, even without the
special tool.

Cheerz, Lynzz

 

[Ronald]

> The device went: bolt, 8mm spanner, nut, washer, flat plate, rivnut. Then it was down to carefully
> tightening the nut with the rivnut inserted in the frame.

Thanks, i was planning on using the same device to fit some rivnuts and wundered if it would work.

"Lindsay Rowlands" <[email protected]> wrote in message
news:[email protected]...
> This may not be a big deal for the 'old man and the bicycle' types, but I've just had my first
> encounter with rivnuts and finally won. I needed to fit water bottle mounts on a frame I've set up
> as a fixed wheeler.
>
> In this small town, the places you'd expect a chance of buying a couple of 5mm rivnuts were
> disappointing. I may as well have been speaking Urdu or Fon. Rivnut is a great trigger for 'Huh?'.
>
> I finally located some at the local aircraft maintenance hanger for $1 each. For all intents and
> purposes aircraft bits and pieces are AF or non-metric. I wasn't deterred and as it turns out 3/16
> fine thread is so close to 5mm x .8 (most water bottle screws) that they're as good as
> interchangeable.
>
> After carefully measuring and drilling the frame, it was time to wrangle with the rivnuts. I'd
> assumed it was just a matter of putting the rivnut in the hole and then tightening a water bottle
> bolt to expand the 'riv' part of the device. Nope. It took a bit of fussing around to locate a
> longer 5mm bolt, nut and a piece of flat plate with a hole the right size. The device went: bolt,
> 8mm spanner, nut, washer, flat plate, rivnut. Then it was down to carefully tightening the nut
> with the rivnut inserted in the frame. I made a point of greasing the washer under the nut so that
> it could spin easily. It was then a matter of feeling when the resistance slightly increased then
> stopping. The rivnuts are aluminium so it would be very easy to strip the threads.
>
> In my searching earlier I came across a rivnut kit with assorted sizes and a pop rivet plyers -
> $160! Sure the plyers would have made the insertion a whole lot easier, but without them I had a
> very intimate learning experience. And I'm quite chuffed to have water bottle mounts where they
> weren't previously and it only cost $2.
>
> So if anyone is thinking about fitting water bottle mounts to a bike I can vouch that is quite
> straight forward and they should have the confidence to take the job on, even without the
> special tool.
>
> Cheerz, Lynzz

 

[Jobst Brandt]

Lindsay Rowlands writes:

> This may not be a big deal for the 'old man and the bicycle' types, but I've just had my first
> encounter with rivnuts and finally won. I needed to fit water bottle mounts on a frame I've set up
> as a fixed wheeler.

> I finally located some at the local aircraft maintenance hanger for $1 each. For all intents and
> purposes aircraft bits and pieces are AF or non-metric. I wasn't deterred and as it turns out 3/16
> fine thread is so close to 5mm x .8 (most water bottle screws) that they're as good as
> interchangeable.

> After carefully measuring and drilling the frame, it was time to wrangle with the rivnuts. I'd
> assumed it was just a matter of putting the rivnut in the hole and then tightening a water bottle
> bolt to expand the 'riv' part of the device.

Not a good idea! I don't know many riders who believe that drilling a hole in a frame tube is a
reasonable concept. I assume the rivnut was securely tightened and painted to prevent motion,
corrosion and water intrusion. Normally a water bottle thread is brazed or welded into the tube,
thereby becoming a structural reinforcement for the hole in the tube. A rivnut is not doing anything
for strength and is not part of the tube and I suspect it will loosen with time, having no preload.

Jobst Brandt [email protected] Palo Alto CA

 

[Mike Jacoubowsk]

> Not a good idea! I don't know many riders who believe that drilling a hole in a frame tube is a
> reasonable concept. I assume the rivnut was securely tightened and painted to prevent motion,
> corrosion and water intrusion. Normally a water bottle thread is brazed or welded into the tube,
> thereby becoming a structural reinforcement for the hole in the tube. A rivnut is not doing
> anything for strength and is not part of the tube and I suspect it will loosen with time, having
> no preload.

Jobst: These days, water bottle bosses are not "normally" brazed or welded into place. Even Reynolds
is suggesting rivnuts for 853, which is amazingly-thin tubing. If you look at modern bikes, you'll
find virtually all of them sporting rivnuts these days, with no more incidence of failure that what
you'd find from the brazed variety (which would sometimes be the point of tube failure, just as the
rivnut style are). The use of rivnuts cuts across all lines... materials (steel, aluminum, carbon,
titanium), pricing (mass produced & custom) and origin (Italian, Chinese, domestic).

--Mike-- Chain Reaction Bicycles http://www.ChainReactionBicycles.com

 

[John Everett]

On Wed, 7 May 2003 16:07:13 +0200, "Ronald" <[email protected]> wrote:

>> The device went: bolt, 8mm spanner, nut, washer, flat plate, rivnut. Then it was down to
>> carefully tightening the nut with the rivnut inserted in the frame.
>
>Thanks, i was planning on using the same device to fit some rivnuts and wundered if it would work.
>
>"Lindsay Rowlands" <[email protected]> wrote in message
>news:[email protected]...
>> This may not be a big deal for the 'old man and the bicycle' types, but I've just had my first
>> encounter with rivnuts and finally won. I needed to fit water bottle mounts on a frame I've set
>> up as a fixed wheeler.
>>
>> In this small town, the places you'd expect a chance of buying a couple of 5mm rivnuts were
>> disappointing. I may as well have been speaking Urdu or Fon. Rivnut is a great trigger for
>> 'Huh?'.
>>
>> I finally located some at the local aircraft maintenance hanger for $1 each.

Last time I needed a Rivnut inserted the guy at the local aircraft maintenance hangar did it with
the proper tool, gratis.

jeverett3<AT>earthlink<DOT>net http://home.earthlink.net/~jeverett3

 

[Lindsay Rowland]

[email protected] wrote:
: Lindsay Rowlands writes:

: Not a good idea! I don't know many riders who believe that drilling a hole in a frame tube is a
: reasonable concept. I assume the rivnut was securely tightened and painted to prevent motion,
: corrosion and water intrusion. Normally a water bottle thread is brazed or welded into the tube,
: thereby becoming a structural reinforcement for the hole in the tube. A rivnut is not doing
: anything for strength and is not part of the tube and I suspect it will loosen with time, having
: no preload.

The strength issue certainly occurred to me and I'll keep an eye on things, though the frame in
question is a nothing-exotic steel number with no intrinsic value other than being an appropriate
receptacle to attach other bike components.

I may be mistaken but I've seen what are suspiciously rivnut-like fittings in late model aluminium
frames. If they're OK for frame makers then I don't feel reckless about taking the risk with a 20
year old steel frame.

Cheerz, Lynzz

 

[Lindsay Rowland]

Ronald <[email protected]> wrote:
:> The device went: bolt, 8mm spanner, nut, washer, flat plate, rivnut. Then it was down to
:> carefully tightening the nut with the rivnut inserted in the frame.

: Thanks, i was planning on using the same device to fit some rivnuts and wundered if it would work.

Some of the details I left out were that I drilled the holes so that the rivnuts were close fitting
and I also deburred them.

The flat plate is to stop the rivnut turning as you tighten up the nut, so anything that is long
enough and with an appropriate close fitting hole will
do.

I should point out too that the thread on the bolt I used for inserting the rivnut stripped probably
because the load on the tightening nut distorted it so be prepared to sacrifice a bolt or two. I
used a couple from a kit of nuts and bolts bought in the local supermarket.

In hindsight, I should have painted some metal etching primer on the bare steel of the hole and
lathered some silicone sealant on the rivnut to keep water out. I'll do that next time.

Lots of luck.

Cheerz, Lynzz

 

[Hillbiker]

I worked as the New Product Engineer for Rivnuts when they were a part of BFGoodrich (1987-1989.)
They won't do anything for the strength of the tube. However, they expand radially into interference
with the hole BEFORE they form a bulge on the back side of the work, so they won't come loose, and
they are "splash-proof" if not fully water-tight.

At one time they made a special which was actually headless, and which held in the workpiece JUST by
the interference with the walls of the hole. In fact, the interference with the hole will actually
keep the head of the Rivnut from drawing down against the workpiece -- if it isn't down when you
start your pull, it may not GO down at all!

> A rivnut is not doing anything for strength and is not part of the tube and I suspect it will
> loosen with time, having no preload.
>
> Jobst Brandt [email protected] Palo Alto CA

 

[Doug Goncz]

>In my searching earlier I came across a rivnut kit with assorted sizes and a pop rivet
>plyers - $160!

Where?

That's way too much!

Yours,

Doug Goncz, Replikon Research, Seven Corners, VA http://users.aol.com/DGoncz If a computer won't do
what needs to be done, lie to it. Don't try this trick on people.

 

[A Muzi]

> >In my searching earlier I came across a rivnut kit with assorted sizes
and
> >a pop rivet plyers - $160!

" Doug Goncz " <[email protected]> wrote in message
news:[email protected]...
> Where? That's way too much!

Too much for a hundred pieces or too much for twenty thousand pieces? Hard to tell, isn't it?
--
Andrew Muzi http://www.yellowjersey.org Open every day since 1 April 1971

 

[Steven Scharf]

Lindsay Rowlands <[email protected]> wrote in message
news:<[email protected]>...
> This may not be a big deal for the 'old man and the bicycle' types, but I've just had my first
> encounter with rivnuts and finally won. I needed to fit water bottle mounts on a frame I've set up
> as a fixed wheeler.

Argh, don't use Rivnuts for this!

See: "http://www.nordicgroup.us/cageboss.htm"

 

[Andy Dingley]

On 9 May 2003 10:40:07 -0700, [email protected] (Steven Scharf) wrote:

>Argh, don't use Rivnuts for this!

Why ?

>See: "http://www.nordicgroup.us/cageboss.htm"

Why ?

"but it looks tacky and unprofessional" is hardly a compelling argument.

As it happens, I was looking in the RAF training notes on airframes tonight. They seem pretty
sanguine about using Rivnuts (and a whole slew of other fastenings, all listed in huge detail). So
what's the problem for downtubes ?

 

[John Everett]

On 9 May 2003 10:40:07 -0700, [email protected] (Steven Scharf) wrote:

>Lindsay Rowlands <[email protected]> wrote in message
>news:<[email protected]>...
>> This may not be a big deal for the 'old man and the bicycle' types, but I've just had my first
>> encounter with rivnuts and finally won. I needed to fit water bottle mounts on a frame I've set
>> up as a fixed wheeler.
>
>Argh, don't use Rivnuts for this!
>
>See: "http://www.nordicgroup.us/cageboss.htm"

I checked the link and Scharf's web site (nordicgroup) claim Rivnuts "look tacky and
unprofessional". My Vitus came with Rivnuts and with the bottle cages in place you can't even see
them. How can something basically invisible look "tacky and unprofessional"?

Meanwhile, Scharf's page touts all kinds of tacky looking methods requiring straps and/or hose clamp
looking things.

jeverett3<AT>earthlink<DOT>net http://home.earthlink.net/~jeverett3

 

[Mike Demicco]

In article <[email protected]>, [email protected] wrote:

> Lindsay Rowlands writes:
>
> > After carefully measuring and drilling the frame, it was time to wrangle with the rivnuts. I'd
> > assumed it was just a matter of putting the rivnut in the hole and then tightening a water
> > bottle bolt to expand the 'riv' part of the device.
>
> Not a good idea! I don't know many riders who believe that drilling a hole in a frame tube is a
> reasonable concept. I assume the rivnut was securely tightened and painted to prevent motion,
> corrosion and water intrusion. Normally a water bottle thread is brazed or welded into the tube,
> thereby becoming a structural reinforcement for the hole in the tube. A rivnut is not doing
> anything for strength and is not part of the tube and I suspect it will loosen with time, having
> no preload.

I concur. Just recently, my Trek 1200 aluminum frame cracked around the seat tube at a crimped-in
(rivnut) threaded insert for the front derailler mount. Had there been no insert (i.e., had the
frame been built for a clamp-on derailler) I doubt the frame would have failed. Clamp-on water
bottle cage mounts are available and the safer choice.

 

[Jobst Brandt]

Mike DeMicco writes:

>>> After carefully measuring and drilling the frame, it was time to wrangle with the Rivnuts. I'd
>>> assumed it was just a matter of putting the Rivnut in the hole and then tightening a water
>>> bottle bolt to expand the 'riv' part of the device.

>> Not a good idea! I don't know many riders who believe that drilling a hole in a frame tube is a
>> reasonable concept. I assume the Rivnut was securely tightened and painted to prevent motion,
>> corrosion and water intrusion. Normally a water bottle thread is brazed or welded into the tube,
>> thereby becoming a structural reinforcement for the hole in the tube. A Rivnut is not doing
>> anything for strength and is not part of the tube and I suspect it will loosen with time, having
>> no preload.

> I concur. Just recently, my Trek 1200 aluminum frame cracked around the seat tube at a crimped-in
> (Rivnut) threaded insert for the front derailleur mount. Had there been no insert (i.e., had the
> frame been built for a clamp-on derailleur) I doubt the frame would have failed. Clamp-on water
> bottle cage mounts are available and the safer choice.

This sound so much like the claims that cranks don't break and that those that do were the result of
any number of unrelated effects, like for instance lubricating the spindle before installation. The
reason that tale got into manufacturer's instruction sheets is because they have a problem. The
results I see are ISIS and that Shimano is still not satisfied with their solution as we see on the
straight spline and pinch bolts on their next generation.

http://www.lancearmstrong.com/lance/online2.nsf/Docs/5331302CD9C5EBBA86256D15006FD9B9

I am still waiting to see what they devise for crank failures at the pedal eye, something far easier
to solve than the spindle attachment.

Cranks break and holes in frame tubes, loaded in torsion and/or bending, causes tube failures.
This is nothing new but as often happens, R&D takes place on the customers shift. If the stresses
around a 1/4" hole in a frame tube were visible, I'm sure few people would even consider drilling
such a hole.

Jobst Brandt [email protected] Palo Alto CA

 

[Steven Scharf]

John Everett <[email protected]> wrote in message

> I checked the link and Scharf's web site (nordicgroup) claim Rivnuts "look tacky and
> unprofessional". My Vitus came with Rivnuts and with the bottle cages in place you can't even see
> them. How can something basically invisible look "tacky and unprofessional"?

There's a big difference when it comes with Rivnuts from the manufacturer (for a very good reason in
the case of the Vitus), and doing it yourself by drilling holes after the fact. And even when
factory installed, there are already enough problems with aluminum tubing to not take any chances
with weakening the tubing even further (see the post in this thread by Mike DeMicco).

IMVAIO, the Zefal Gizmo Clamps, the KLICKFix Bottle Fix, and the Minoura bottle cage holder, are
solutions to the problem that do not have the downside of weakening the frame or allowing water to
get inside the frame. They look no worse that the various clamps that hold other accessories, such
as computers, onto the bicycle.

Everyone would prefer that their frame has cage bosses from the factory, be they braze-ons or
factoty installed Rivnuts. When this is not the case, the prudent method for adding bottle mounts is
to use one of the many clamps that are available.

 

[Andy Dingley]

On 12 May 2003 15:36:16 -0700, [email protected] (Steven Scharf) wrote:

>There's a big difference when it comes with Rivnuts from the manufacturer (for a very good reason
>in the case of the Vitus), and doing it yourself by drilling holes after the fact.

Why ? Why can't a Rivnut be perfectly well installed afterwards ? It's what they're designed for !

 

[John Everett]

On Tue, 13 May 2003 13:55:56 +0100, Andy Dingley <[email protected]> wrote:

>On 12 May 2003 15:36:16 -0700, [email protected] (Steven Scharf) wrote:
>
>>There's a big difference when it comes with Rivnuts from the manufacturer (for a very good reason
>>in the case of the Vitus), and doing it yourself by drilling holes after the fact.
>
>Why ? Why can't a Rivnut be perfectly well installed afterwards ? It's what they're designed for !

Exactly!

jeverett3<AT>earthlink<DOT>net http://home.earthlink.net/~jeverett3

 

[Steven M. Schar]

"Andy Dingley" <[email protected]> wrote in message
news:[email protected]...
> On 12 May 2003 15:36:16 -0700, [email protected] (Steven Scharf) wrote:
>
> >There's a big difference when it comes with Rivnuts from the manufacturer (for a very good reason
> >in the case of the Vitus), and doing it yourself by drilling holes after the fact.
>
> Why ? Why can't a Rivnut be perfectly well installed afterwards ? It's what they're designed for !

The Rivnut was designed for it, but the bicycle frame was not designed for it. They can be installed
in older steel frames.

 

[Andy Dingley]

On Tue, 13 May 2003 15:36:30 GMT, "Steven M. Scharf" <[email protected]> wrote:

>The Rivnut was designed for it, but the bicycle frame was not designed for it. They can be
>installed in older steel frames.

Anyone got any evidence of a frame that failed at the waterbottle mounts, Rivnut or not ?

It's like the way that thin swaged spokes don't cause wheel failures. Yes, they're obviously less
strong at that point. But that's not where the _structure_ fails.

Never ask a metallurgist to do a structural engineer's job.