Tapping ti

[David]

I took my Titanium hardtail to the bike shop where I got it to see about rack installation. It
doesn't have rack mounts. Drilling & tapping the dropouts seems like a good solution, but the shop
said they can't because you need a special tap for Ti. I'm skeptical. As far as I remember, the
dropouts are CP titanium. The rest of the bike (and dropouts too if I'm wrong) is 3/2.5.

I thought CP was easier to drill/tap than chromo steel. I could hunt around on matweb, and tryto
figure this out (and still maybe get the wrong answer). Better to ask the experts.

Can they make rack mounts with a normal tap if it's CP? If it's 3/2.5? Should I go elsewhere to have
it done. I'm in the east SF Bay area, and this shop (Sharp's Bicycles in Lafayette) has always done
good work for me.

As an interim solution, I'll probably use bands around the seat-stays to mount the rack, but that
doesn't seem very stable.

Thanks, David

 

[Jim Beam]

don't drill & tap the dropout. you'll seriously weaken it.

go to nashbar.com and search for bolt-on rack eyelets instead.

jb

 

[David]

"jim beam" <[email protected]> wrote in message news:[email protected]...
> don't drill & tap the dropout. you'll seriously weaken it.

It's a stout dropout. I don't think it will crack. I doubt it will flex more with a bolt in place.
It was the bike shop's idea, but they said they didn't have the tools.

> go to nashbar.com and search for bolt-on rack eyelets instead.

I've already got the band type that attach to the seat stays (from the misc parts kit I bought last
time I installed a rack). The only hit I found at nashbar came without photo or detailed
description, so I can't tell if it's any better, or exactly what it is.

If you see something better there, please post a link.

Thanks, David

 

[Mark Vieselmeye]

David <[email protected]> wrote:
: I took my Titanium hardtail to the bike shop where I got it to see about rack installation. It
: doesn't have rack mounts. Drilling & tapping the dropouts seems like a good solution, but the shop
: said they can't because you need a special tap for Ti. I'm skeptical. As far as I remember, the
: dropouts are CP titanium. The rest of the bike (and dropouts too if I'm wrong) is 3/2.5.

I've done it on two ti bikes with no problems. Just drilled it with a hand drill and tapped it with
a cheap T-handle tap that I got from the local hardware store. Drilling without a drill-press was a
real pain, but tapping it was easy. My dropouts are fairly big, with plenty of space to position the
hole -- before you try it make sure you'll have enough clearance so the rack strut won't interfere
with the wheel skewer.

- mark

 

[David L. Johnso]

On Mon, 20 Oct 2003 23:04:02 +0000, jim beam wrote:

> don't drill & tap the dropout. you'll seriously weaken it.

Pshaw. Unless it's a high-zoot minimal dropout, it should have lots of extra material. If as the OP
said his dropouts are CP, it is not that fancy a bike. Probably, though, the dropouts are either
3/2.5 or 6/4.

Ti is also not that hard. Comparable to steel.
>
> go to nashbar.com and search for bolt-on rack eyelets instead.

A better solution. Go to a hardware store. Get "P-clamps". You can find them in various sizes,
usually with a rubber cover that will cut down scratches. That's what I used, and had no trouble. It
might be easier to fit with drilled and tapped holes, but the clamps work fine.

--

David L. Johnson

__o | More people object to wearing fur than leather because it is _`\(,_ | safer to harrass rich
white women than motorcycle gangs. (_)/ (_) |

 

[Jim Beam]

ok, please do me a favor. try and find and post a link to a pic that shows your dropout. it /may/
have sufficient spare material to locate a drilling, but it's a function of the dropout section, not
thickness. it would be unusual for a ti dropout to have sufficient - they're usually fairly
ungenerous to minimise [expensive] material costs.

to answer your original question, drilling & tapping is not a problem as far as the tools are
concerned. not for a one-off at any rate.

jb

David wrote:

> "jim beam" <[email protected]> wrote in message news:[email protected]...
>
>>don't drill & tap the dropout. you'll seriously weaken it.
>
>
> It's a stout dropout. I don't think it will crack. I doubt it will flex more with a bolt in place.
> It was the bike shop's idea, but they said they didn't have the tools.
>
>
>>go to nashbar.com and search for bolt-on rack eyelets instead.
>
>
> I've already got the band type that attach to the seat stays (from the misc parts kit I bought
> last time I installed a rack). The only hit I found at nashbar came without photo or detailed
> description, so I can't tell if it's any better, or exactly what it is.
>
> If you see something better there, please post a link.
>
> Thanks, David
>

 

[Mark Hickey]

"David" <[email protected]> wrote:

>I took my Titanium hardtail to the bike shop where I got it to see about rack installation. It
>doesn't have rack mounts. Drilling & tapping the dropouts seems like a good solution, but the shop
>said they can't because you need a special tap for Ti. I'm skeptical. As far as I remember, the
>dropouts are CP titanium. The rest of the bike (and dropouts too if I'm wrong) is 3/2.5.
>
>I thought CP was easier to drill/tap than chromo steel. I could hunt around on matweb, and tryto
>figure this out (and still maybe get the wrong answer). Better to ask the experts.
>
>Can they make rack mounts with a normal tap if it's CP? If it's 3/2.5? Should I go elsewhere to
>have it done. I'm in the east SF Bay area, and this shop (Sharp's Bicycles in Lafayette) has always
>done good work for me.
>
>As an interim solution, I'll probably use bands around the seat-stays to mount the rack, but that
>doesn't seem very stable.

If the DO's are indeed CP ti (which is the best choice IMHO) it shouldn't be too hard to drill and
tap them. Harder than aluminum, yes. Than steel? Yes (by "harder", I mean "more difficult").

Just take your time, use lots of lube, and really make sure you have lots of extra real estate to
handle the hole.

I've also had good luck with the shouldered washers that mount behind any hole in the DO (sometimes
they have to be ground down a bit to work, but it's a light, cheap and simple solution that works
quite well).

Mark Hickey Habanero Cycles http://www.habcycles.com Home of the $695 ti frame

 

[Carl Fogel]

"David" <[email protected]> wrote in message
news:<[email protected]>...

[snip]

Dear David,

If I were in your shoes, I'd wait for Chalo Contina to post a comment.

If Chalo didn't comment, I'd email him in hopes of getting the opinion of a bicycle enthusiast,
regular poster, and professional machinist.

(No offense to other posters, who may well know as much and even be machinists like Chalo.)

Carl Fogel

 

[A Muzi]

jim beam wrote:
> don't drill & tap the dropout. you'll seriously weaken it.
>
> go to nashbar.com and search for bolt-on rack eyelets instead.

There are exceptions , but usually this is a simple, quick and safe operation.

Perhaps if you had quoted even one word of the original I'd know why you said that.
--
Andrew Muzi www.yellowjersey.org Open every day since 1 April, 1971

 

[Pat Clancy]

"David" <[email protected]> wrote in message
news:<[email protected]>...
> I took my Titanium hardtail to the bike shop where I got it to see about rack installation. It
> doesn't have rack mounts. .......

Have you looked at racks from Old Man Mountain? (oddly enough, oldmanmountain.com)

Their racks do not require braze-ons or eyelets. They can be mounted using the wheel skewer. I
bought one for my Bianchi road bike, which had no rack eyelets and not enough meat on the
dropouts to drill.

Pat Clancy

 

[Jim Beam]

> Perhaps if you had quoted even one word of the original I'd know why you said that.

use a threaded news reader?

 

[David]

"Pat Clancy" <[email protected]> wrote in message
news:[email protected]...
> Have you looked at racks from Old Man Mountain? (oddly enough, oldmanmountain.com)
>
> Their racks do not require braze-ons or eyelets. They can be mounted using the wheel skewer.

I knew I had seen something like that before. I was thinking of skewer-mounted adapters though.
Asked at the LBS but no luck. I bought a regular rack yesterday, but I'll look at those.

Thanks. And thanks to everyone else for the helpful responses also. It looks like I have a lot of
good solutions.

David

 

[Tom Nakashima]

pretty funny jim, -tom

"jim beam" <[email protected]> wrote in message news:[email protected]...
> > Perhaps if you had quoted even one word of the original I'd know why you said that.
>
> use a threaded news reader?

 

[Chalo]

"David" <[email protected]> wrote:

> Drilling & tapping the dropouts seems like a good solution, but the shop said they can't because
> you need a special tap for Ti. I'm skeptical. As far as I remember, the dropouts are CP titanium.
> The rest of the bike (and dropouts too if I'm wrong) is 3/2.5.

It should not be too big a deal either way. Drilling is probably the harder of the two steps.
Centerpunch your hole location, and try to keep the pressure on and the bit cutting continuously,
because the work-hardened surface where you stop drilling can be a real nuisance.

Use an "all metals" tapping fluid or a molybdenum disulfide lubricant, and get a nice sharp ground
tap at your local bolt place or machine tool supply. The usual hardware store kind are pretty dull
right out of the package.

Don't try to cut too deep a thread; your tap drill should be no smaller than the diameter of the
fastener, minus one pitch length. For an M5x0.8 tap that means the tap drill should be no less than
4.2mm or .165" That's a #19 drill bit if metric ones aren't readily available to you.

Good luck.

Chalo Colina

 

[Peter]

"David" <[email protected]> wrote in message
news:[email protected]...
> I took my Titanium hardtail to the bike shop where I got it to see about
rack installation.
> It doesn't have rack mounts. Drilling & tapping the dropouts seems like a
good
> solution, but the shop said they can't because you need a special tap for
Ti. I'm
> skeptical. As far as I remember, the dropouts are CP titanium. The rest
of the bike
> (and dropouts too if I'm wrong) is 3/2.5.
>
cut...

Had this done on my 2002 bike based on a rock lobster ti frame I used for a ride from Calais to
Finisterre. 2000 plus miles loaded for camping and at 16 stone plus I'm not a lightweight. No
problems at all with the rack or dropouts.

LBS didn't want to know so I had it done by a local engineering firm, took about ten minutes.

Theres a picture of the rack on the bike about halfway down:
http://www.fastload.net/03/two/pages/index.html

A larger slow loading picture at http://www.fastload.net/03/two/picpages/carrier.html shows more
detail peter

 

[A Muzi]

([email protected]) kvetched:
>> Perhaps if you had quoted even one word of the original I'd know why you said that.

jim beam helpfully suggested:
> use a threaded news reader?

Yes, I have mood swings like everyone else and I'll apologize for being snitty.

Still it is nice to quote the salient points in a reply. "Salient" being something beyond zero and
less than (as Dave Damerell reminded recently) the entire history of the universe.

--
Andrew Muzi www.yellowjersey.org Open every day since 1 April, 1971

 

[Simon Brooke]

jim beam <[email protected]> writes:

> > Perhaps if you had quoted even one word of the original I'd know why you said that.
>
>
> use a threaded news reader?

Why is it that people find the concept of a store-and-forward network so hard to understand?

There is a collection of news servers. Each news server exchanges messages with a few others. Some
news servers maintain more or less continuous connections with their peers, but many (probably most)
communicate with each peer only intermittently, batching up posts before resending them. My server,
for example, communicates with its peers once every twenty minutes, so there is a minimum of a
twenty minute delay for a message to traverse my node.

The route any given message takes through the network is not deterministic. Furthermore, it's not
real time or even quick. When a message arrives at any given server, it will be batched up and
queued to be offered to other peers of that server. The consequence is it can take up to several
days for any given message to traverse the network, and certainly journey times of hours are not
unusual. Finally, different servers age out messages according to different rules.

Just because you can see a message on your local server does not mean that I can see the same
message on my local server. It may not yet have reached my server, or it may already have aged out.
This is why quoting is important, and why a threaded newsreader doesn't make the slightest bit of
difference to the importance of quoting. Usenet is not real time.

--
[email protected] (Simon Brooke) http://www.jasmine.org.uk/~simon/

Wise man with foot in mouth use opportunity to clean toes.
;; the Worlock

 

[Jim Beam]

> Still it is nice to quote the salient points in a reply.

since you put it so nicely, it will be a pleasure to oblige!

best

j

 

[David]

"peter" <[email protected]> wrote in message news:[email protected]...
>> Theres a picture of the rack on the bike about halfway down:
> http://www.fastload.net/03/two/pages/index.html
>
That was really good stuff. Thanks!

My wife's bike was stolen a few days ago. It was an old-school MTB set up as a grocery-getter. I was
converting my Bontrager Ti Lite for her. Bought a beautiful Jandd rack. For the initial mounting I
used bands around the seat stays. Not even close to providing heel clearance with her open-top
panniers mounted. Moving the rack back a few cm (with an eyelet mount) wouldn't be enough.

Now it's time to explore unconventional racks (e.g., Old Man Mountain & Delta).

David

 

[David Damerell]

jim beam <[email protected]> wrote:
>Andrew Muzi wrote, but some idiot deletes attribution lines:
>>Perhaps if you had quoted even one word of the original I'd know why you said that.
>use a threaded news reader?

Come back when you know what "propagation problems" are.
--
David Damerell <[email protected]> Kill the tomato!