BB Chasing Tap

monkeyboy said:

Does anyone know where I can find an inexpensive chasing tap for a
bottom bracket? I don't need to cut fresh treads, just clean-up
existing ones.

Thanks

Frank

Cyclus

--
---
Marten Gerritsen

INFOapestaartjeM-GINEERINGpuntNL
www.m-gineering.nl

Quoted message said:

Does anyone know where I can find an inexpensive chasing tap for a
bottom bracket? I don't need to cut fresh treads, just clean-up
existing ones.

Thanks

Frank

Frank: Even cleaning up existing threads requires a pretty nice tool to do
the job right. But if this is just an attempt to salvage a cheap frame, and
you can't bring it to a shop to have them clean the threads for you (which
would cost a lot less than a cheap chasing tap), you could try to make your
own. Just use an old bottom bracket, hacksaw some cuts across the threads
(not quite perpendicular) and give it a try.

--Mike-- Chain Reaction Bicycles
www.ChainReactionBicycles.com

monkeyboy said:

Does anyone know where I can find an inexpensive chasing tap for a
bottom bracket? I don't need to cut fresh treads, just clean-up
existing ones.

Thanks

Frank

biketoolsetc.com has some Hozan chasers:

http://tinyurl.com/dquxe

Not "cheap" but less expensive than others. Caution! Where it says RH
and LH on each one it doesn't mean "use on left hand side" or "use on
right hand side", it means "right handed threads, left handed threads"
(Gee, how do suppose I know that now...)

Joseph

Mike Jacoubowsky said:

Quoted message said:

Does anyone know where I can find an inexpensive chasing tap for a
bottom bracket? I don't need to cut fresh treads, just clean-up
existing ones.

Thanks

Frank

Frank: Even cleaning up existing threads requires a pretty nice tool to do
the job right. But if this is just an attempt to salvage a cheap frame, and
you can't bring it to a shop to have them clean the threads for you (which
would cost a lot less than a cheap chasing tap), you could try to make your
own. Just use an old bottom bracket, hacksaw some cuts across the threads
(not quite perpendicular) and give it a try.

Sounds like a neat idea, but aren't steel BB cups hardened? Or is the
hardening somehow localized to the bearing surfaces so that it doesn't
extend to the threaded part of the cup?

A carbide(?) rod saw would do it, but I think a hacksaw might not "cut it".

Mark

Looks like I'll have to take it to a shop. I couldn't believe the price
of a BB tap...jeeesss.

I did find a thread restoring tool in McMaster Carr that would be just
the ticket, but it would cost around $50 for the tool and die set.

It looks like who ever initially installed the BB didn't lube it at
all. I had to take it out with a hammer, and now the threads are packed
with aluminum from the old BB shell. I tried using a pick to dig it
out, but it's really packed in there.

Mark Janeba said:

Mike Jacoubowsky said:

Quoted message said:

Does anyone know where I can find an inexpensive chasing tap for a
bottom bracket? I don't need to cut fresh treads, just clean-up
existing ones.

Thanks

Frank

Frank: Even cleaning up existing threads requires a pretty nice tool to do
the job right. But if this is just an attempt to salvage a cheap frame, and
you can't bring it to a shop to have them clean the threads for you (which
would cost a lot less than a cheap chasing tap), you could try to make your
own. Just use an old bottom bracket, hacksaw some cuts across the threads
(not quite perpendicular) and give it a try.

Sounds like a neat idea, but aren't steel BB cups hardened? Or is the
hardening somehow localized to the bearing surfaces so that it doesn't
extend to the threaded part of the cup?

A carbide(?) rod saw would do it, but I think a hacksaw might not "cut it".

Mark

Hozan makes one and a complete LBS may have one
or a complete set of BB taps

M-gineering said:

monkeyboy said:

Does anyone know where I can find an inexpensive chasing tap for a
bottom bracket? I don't need to cut fresh treads, just clean-up
existing ones.

Thanks

Frank

Cyclus

Just another vote for the Cyclus. Nice home shop tool at a fair price.

Quoted message said:

Hozan makes one and a complete LBS may have one
or a complete set of BB taps

biketoolsetc.com has them it you can't find locally.

Joseph

Quoted message said:

Quoted message said:

Frank: Even cleaning up existing threads requires a pretty nice tool to
do the job right. But if this is just an attempt to salvage a cheap
frame, and you can't bring it to a shop to have them clean the threads
for you (which would cost a lot less than a cheap chasing tap), you could
try to make your own. Just use an old bottom bracket, hacksaw some cuts
across the threads (not quite perpendicular) and give it a try.

Sounds like a neat idea, but aren't steel BB cups hardened? Or is the
hardening somehow localized to the bearing surfaces so that it doesn't
extend to the threaded part of the cup?

A carbide(?) rod saw would do it, but I think a hacksaw might not "cut
it".

Mark

Inexpensive bottom brackets aren't anything to write home about; the threads
can be cut fairly easily. Perhaps not with a hacksaw though; I believe I've
done it with a file or dremel tool way, way, WAY back in the day. I
certainly didn't have a carbide rod saw at my disposal though!

--Mike Jacoubowsky
Chain Reaction Bicycles
www.ChainReaction.com
Redwood City & Los Altos, CA USA

"Mike Jacoubowsky" wrote: (clip)I certainly didn't have a carbide rod saw
at my disposal though
^^^^^^^^^^^^
The harder the threads are, the better the "fake" tap will work, provided
you can cut the slots. If you are talking about the kind of carbide rod saw
I am thinking of, I doubt it will work. Are you thinking of one of those
round hack-saw blades with carbide bits embedded along the length? Due to
the fact that it is round, it will make a "cove," rather than a
straight-sided slot, and the chances are it would not cut very well. An
abrasive disk in a Dremel would be your best bet.

"Leo Lichtman" <[email hidden]> wrote in message
news:[email hidden]...

Quoted message said:

"Mike Jacoubowsky" wrote: (clip)I certainly didn't have a carbide rod saw
at my disposal though
^^^^^^^^^^^^
The harder the threads are, the better the "fake" tap will work, provided
you can cut the slots. If you are talking about the kind of carbide rod
saw I am thinking of, I doubt it will work. Are you thinking of one of
those round hack-saw blades with carbide bits embedded along the length?
Due to the fact that it is round, it will make a "cove," rather than a
straight-sided slot, and the chances are it would not cut very well. An
abrasive disk in a Dremel would be your best bet.

What is a "fake" tap?
-tom

Tom Nakashima said:

"Leo Lichtman" <[email hidden]> wrote in message
news:[email hidden]...

Quoted message said:

"Mike Jacoubowsky" wrote: (clip)I certainly didn't have a carbide rod saw
at my disposal though
^^^^^^^^^^^^
The harder the threads are, the better the "fake" tap will work, provided
you can cut the slots. If you are talking about the kind of carbide rod
saw I am thinking of, I doubt it will work. Are you thinking of one of
those round hack-saw blades with carbide bits embedded along the length?
Due to the fact that it is round, it will make a "cove," rather than a
straight-sided slot, and the chances are it would not cut very well. An
abrasive disk in a Dremel would be your best bet.

What is a "fake" tap?
-tom

What Mike J. just described above, John

Tom Nakashima said:

"Leo Lichtman" <[email hidden]> wrote in message
news:[email hidden]...

Quoted message said:

"Mike Jacoubowsky" wrote: (clip)I certainly didn't have a carbide rod saw
at my disposal though
^^^^^^^^^^^^
The harder the threads are, the better the "fake" tap will work, provided
you can cut the slots. If you are talking about the kind of carbide rod
saw I am thinking of, I doubt it will work. Are you thinking of one of
those round hack-saw blades with carbide bits embedded along the length?
Due to the fact that it is round, it will make a "cove," rather than a
straight-sided slot, and the chances are it would not cut very well. An
abrasive disk in a Dremel would be your best bet.

What is a "fake" tap?
-tom

What Mike J. just described above, John

Quoted message said:

What is a "fake" tap?
-tom

A "fake" tap is one you make yourself, by cutting slots into a bolt that
threads into the hole.

--Mike Jacoubowsky
Chain Reaction Bicycles
www.ChainReaction.com

Redwood City & Los Altos, CA USA
"Tom Nakashima" <[email hidden]> wrote in message
news:[email hidden]...

Quoted message said:

"Leo Lichtman" <[email hidden]> wrote in message
news:[email hidden]...

Quoted message said:

"Mike Jacoubowsky" wrote: (clip)I certainly didn't have a carbide rod
saw at my disposal though
^^^^^^^^^^^^
The harder the threads are, the better the "fake" tap will work, provided
you can cut the slots. If you are talking about the kind of carbide rod
saw I am thinking of, I doubt it will work. Are you thinking of one of
those round hack-saw blades with carbide bits embedded along the length?
Due to the fact that it is round, it will make a "cove," rather than a
straight-sided slot, and the chances are it would not cut very well. An
abrasive disk in a Dremel would be your best bet.

What is a "fake" tap?
-tom

Mike J. said:

Inexpensive bottom brackets aren't anything to write home about; the threads
can be cut fairly easily. Perhaps not with a hacksaw though; I believe I've
done it with a file or dremel tool way, way, WAY back in the day. I
certainly didn't have a carbide rod saw at my disposal though!

--Mike Jacoubowsky
Chain Reaction Bicycles
www.ChainReaction.com
Redwood City & Los Altos, CA USA

Hi Mike & all
I've never understood;
1. How a rigid or guided BB Tap such as a Campy or Park BTS 1, can
correct existing threads w/o cutting into them, there by reducing the
amount of material in the "V"s of the threads, causing either slop in
the threads and / or a weakening of the threads.
2. In this day & age of outboard BB bearings & cartage bearing BBs,
Facing seems more important. The steel exterior of the cartridge seems
to me like it would mitigate against minor thread misalignment and the
outside bearing housing should be butted against the BB face causing
the housing to align w/ a true BB face. Don't get me wrong, I would
love to use & own a BB tap & facer. It's just when I think carefully
about the taping function, I wonder.
Please be so kind as to explain the errors in my thinking.

Thanks, John

Quoted message said:

I've never understood;
1. How a rigid or guided BB Tap such as a Campy or Park BTS 1, can
correct existing threads w/o cutting into them, there by reducing the
amount of material in the "V"s of the threads, causing either slop in
the threads and / or a weakening of the threads.

I've wondered about that one too, but apparently you can in fact re-shape
the metal somewhat, without removing much. A severly cross-threaded bottom
bracket will require more extensive work though; back in the day we used to
braze some material into the threads and then run the taps. Obviously, this
destroys the paint in the area, and also runs the risk of damaging the frame
from excessive heat if you're not careful.

Quoted message said:

2. In this day & age of outboard BB bearings & cartage bearing BBs,
Facing seems more important. The steel exterior of the cartridge seems
to me like it would mitigate against minor thread misalignment and the
outside bearing housing should be butted against the BB face causing
the housing to align w/ a true BB face.

Facing bottom brackets isn't such an issue anymore for most new frames; when
they're built at the factory, they're threaded and faced at the same time.

Quoted message said:

Don't get me wrong, I would
love to use & own a BB tap & facer. It's just when I think carefully
about the taping function, I wonder.
Please be so kind as to explain the errors in my thinking.

Thanks, John

--Mike Jacoubowsky
Chain Reaction Bicycles
www.ChainReaction.com
Redwood City & Los Altos, CA USA
"john" <[email hidden]> wrote in message
news:[email hidden]...

Quoted message said:

Mike J. said:

Inexpensive bottom brackets aren't anything to write home about; the
threads
can be cut fairly easily. Perhaps not with a hacksaw though; I believe
I've
done it with a file or dremel tool way, way, WAY back in the day. I
certainly didn't have a carbide rod saw at my disposal though!

--Mike Jacoubowsky
Chain Reaction Bicycles
www.ChainReaction.com
Redwood City & Los Altos, CA USA

Hi Mike & all
I've never understood;
1. How a rigid or guided BB Tap such as a Campy or Park BTS 1, can
correct existing threads w/o cutting into them, there by reducing the
amount of material in the "V"s of the threads, causing either slop in
the threads and / or a weakening of the threads.
2. In this day & age of outboard BB bearings & cartage bearing BBs,
Facing seems more important. The steel exterior of the cartridge seems
to me like it would mitigate against minor thread misalignment and the
outside bearing housing should be butted against the BB face causing
the housing to align w/ a true BB face. Don't get me wrong, I would
love to use & own a BB tap & facer. It's just when I think carefully
about the taping function, I wonder.
Please be so kind as to explain the errors in my thinking.

Thanks, John

monkeyboy said:

Does anyone know where I can find an inexpensive chasing tap for a
bottom bracket? I don't need to cut fresh treads, just clean-up
existing ones.

Even guys who build engines at home send out valve grinding.
Sometimes it makes sense to have it done with first class tools.

Although I know several sources for Campagnolo, Cobra and
Silva taps I can't help you find cheap ones. Raleigh used
to sell a unpiloted HKC set at a very low price- maybe an
old Raleigh dealership near you might want to sell them?

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

Quoted message said:

Quoted message said:

Quoted message said:

Frank:
Does anyone know where I can find an inexpensive

chasing tap for a

Quoted message said:

Quoted message said:

Quoted message said:

bottom bracket? I don't need to cut fresh treads, just clean-up
existing ones.

Quoted message said:

Mike Jacoubowsky said:

Frank: Even cleaning up existing threads requires a pretty nice tool
to do the job right. But if this is just an attempt to salvage a cheap
frame, and you can't bring it to a shop to have them clean the threads
for you (which would cost a lot less than a cheap chasing tap), you
could try to make your own. Just use an old bottom bracket, hacksaw
some cuts across the threads (not quite perpendicular) and give it a try.

Mark Janeba said:

Sounds like a neat idea, but aren't steel BB cups hardened? Or is the
hardening somehow localized to the bearing surfaces so that it doesn't
extend to the threaded part of the cup?

A carbide(?) rod saw would do it, but I think a hacksaw might not "cut it".

Yes, Miks's suggestion was clever, use a carbide-coated wire
(any hardware store). They fit in your hacksaw frame.

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

A Muzi said:

monkeyboy said:

Does anyone know where I can find an inexpensive chasing tap for a
bottom bracket? I don't need to cut fresh treads, just clean-up

Quoted message said:

Although I know several sources for Campagnolo, Cobra and
Silva taps I can't help you find cheap ones. Raleigh used
to sell a unpiloted HKC set at a very low price- maybe an
old Raleigh dealership near you might want to sell them?

EDCO made a cheap unpiloted set as well. They turn up occaissionally on
eBay.

--

-John ([email hidden])