Anyone make their own line boring bar/equipment? It doesn't look that hard
to make and could be handy on jobs that are too big for machine tools. Just
wondering if there are any good plans or project info on these. The stuff
looks pretty expensive to buy new for what it is.

RogerN

"RogerN" fired this volley in
:

Anyone make their own line boring bar/equipment? It doesn't look that
hard to make and could be handy on jobs that are too big for machine
tools. Just wondering if there are any good plans or project info on
these. The stuff looks pretty expensive to buy new for what it is.

RogerN




I made a simple jig that mounts the work on the cross-slide, and holds
the boring tool between centers. It allows me much longer bores than a
single-ended boring bar mounted in the tool holder would.

It's really nothing more than a plate to which I clamp or screw the work.
The boring bar is a piece of 5/8" stock with a hole for the tool bit and
a hole for a setscrew, plus center pockets on both ends. Drive it with a
dog.

About the only drawback is that the bore size is limited to the amount of
tool overhang you can afford; with my little 1/4" bit, that's about
1.25"(or a bore of 2.5" max) before chatter kills the job. And, of
course, you have to adjust the tool on every cut, rather than moving the
cross-slide.

But it works.

LLoyd

"RogerN" wrote in message
...
Anyone make their own line boring bar/equipment? It doesn't look that
hard to make and could be handy on jobs that are too big for machine
tools. Just wondering if there are any good plans or project info on
these. The stuff looks pretty expensive to buy new for what it is.

RogerN



Depends on the job. Years ago, on Hopto excavators, my dad would mount an
engine cylinder boring machine to the side of the boom to bore out the pivot
pin area, to install a replaceble pin in made.

"Lloyd E. Sponenburgh" lloydspinsidemindspring.com wrote in message
. 3.70...
"RogerN" fired this volley in
:

Anyone make their own line boring bar/equipment? It doesn't look that
hard to make and could be handy on jobs that are too big for machine
tools. Just wondering if there are any good plans or project info on
these. The stuff looks pretty expensive to buy new for what it is.

RogerN




I made a simple jig that mounts the work on the cross-slide, and holds
the boring tool between centers. It allows me much longer bores than a
single-ended boring bar mounted in the tool holder would.

It's really nothing more than a plate to which I clamp or screw the work.
The boring bar is a piece of 5/8" stock with a hole for the tool bit and
a hole for a setscrew, plus center pockets on both ends. Drive it with a
dog.

About the only drawback is that the bore size is limited to the amount of
tool overhang you can afford; with my little 1/4" bit, that's about
1.25"(or a bore of 2.5" max) before chatter kills the job. And, of
course, you have to adjust the tool on every cut, rather than moving the
cross-slide.

But it works.

This is essentially how the original boring machines worked. Lots of early
automobile engine blocks were actually bored on lathes.

Some of the old English MAP books show miniature versions of those old
boring setups on lathes. Brit lathes, which traditionally have T-slotted
cross slides (or saddles; I forget which) are ideal for that work.

--
Ed Huntress

On Tue, 2 Mar 2010 19:59:07 -0800, "Bill McKee"
wrote:


"RogerN" wrote in message
...
Anyone make their own line boring bar/equipment? It doesn't look that
hard to make and could be handy on jobs that are too big for machine
tools. Just wondering if there are any good plans or project info on
these. The stuff looks pretty expensive to buy new for what it is.

RogerN



Depends on the job. Years ago, on Hopto excavators, my dad would mount an
engine cylinder boring machine to the side of the boom to bore out the pivot
pin area, to install a replaceble pin in made.


I seem to recall a rig by Wayne Cook. Maybe he'll chime in.

Pete Keillor

In article ,
"RogerN" wrote:

Anyone make their own line boring bar/equipment? It doesn't look that hard
to make and could be handy on jobs that are too big for machine tools. Just
wondering if there are any good plans or project info on these. The stuff
looks pretty expensive to buy new for what it is.

RogerN

Haven't got there yet, but I'm with you. I need one and they seem to be
priced too high for what they are. At some point when I asked about it
getting an old bridgeport head (from folks rebuilding and upgrading the
head) was suggested as a power-unit & feed option. I've also seen
mention of getting one from army surplus, but have never seen such
myself.

--
Cats, coffee, chocolate...vices to live by

On Mar 2, 7:54*pm, "RogerN" wrote:
Anyone make their own line boring bar/equipment? *It doesn't look that hard
to make and could be handy on jobs that are too big for machine tools. *Just
wondering if there are any good plans or project info on these. *The stuff
looks pretty expensive to buy new for what it is.

RogerN

A lot of that type of thing is specific to the job at hand, locomotive
steam cylinders, VW engine cases, compressor shells, car engines,
etc. One of Guy Lautard's Bedside Readers had a description of such a
rig and some of Colvin and Stanley's works described what they built
up in locomotive shops to redo cylinders in situ. The Model Engineer
magazine had a lot of such setups on the old Brit lathes, they had T-
slots on the carriages so were easy to rig up. The cutter bar spun
between centers and the work was fastened on the carriage and
traversed with same. What you need to build is pretty much determined
by what you need to machine. A lot of what they used to do with such
rigs on a lathe is now done with boring heads on a mill. Basically
all you need is a tool holder, a way to guide it through the rough
bore, a method of spinning it and another one to periodically move it
down the line. You'll also need some way of fastening the works so it
doesn't move relative to the workpiece. The last could be easy or
could be hard, depending on what you want to work on. A star wheel
advance for the cutter is pretty easy to rig.

Stan

On Wed, 03 Mar 2010 06:24:47 -0600, Pete Keillor wrote:
On Tue, 2 Mar 2010 19:59:07 -0800, "Bill McKee"... wrote:
"RogerN" regor... wrote ...
Anyone make their own line boring bar/equipment? It doesn't look that
hard to make and could be handy on jobs that are too big for machine
tools. Just wondering if there are any good plans or project info on
these. The stuff looks pretty expensive to buy new for what it is.

Depends on the job. Years ago, on Hopto excavators, my dad would mount
an engine cylinder boring machine to the side of the boom to bore out
the pivot pin area, to install a replaceble pin in made.

I seem to recall a rig by Wayne Cook. Maybe he'll chime in.

Or maybe not ~ but anyway, in DropBox/_2002_retired_files, see:
http://www.metalworking.com/DropBox/_2002_retired_files/Lineboring00.txt
http://www.metalworking.com/DropBox/_2002_retired_files/Lineboring01.jpg
http://www.metalworking.com/DropBox/_2002_retired_files/Lineboring02.jpg
http://www.metalworking.com/DropBox/_2002_retired_files/Lineboring03.jpg

(Per 2002 section of
http://members.dslextreme.com/users/waynecook/dropbox.htm )

--
jiw