I have a basic Bridgeport universal mill and a small (8 inch swing)
Harrison lathe. I need to alter some home fabricated lower suspension arms
from a race car. I cut off the stock compliant rubber bushed "eye" from the
arms, and welded in a drilled and tapped buttress to take a rod end. I now
find the geometry of the car has proven to need yet more negative camber.
The rod ends are now threaded right out, so the ends of the threaded shanks
are just flush with the inside walls of the buttresses. I need them about a
quarter of an inch further exttended, and ideally for the rod ends to have
less shank out of the buttress for added safety and strength. I have
decided to bore ou the threaded holes to take a steel tube, internally
threaded 5/8 UNF for the existing rod ends. I am unsure of the best way to
hold the arms to allow me to drill concentrically with the existing
threaded hole to take a sleeve which I envisage as having about a 5mm wall
thickness. This will effectively extend the buttress further outboard, and
the existing rod end will screw into it and use the same type of locknut
against the end of the sleeve. Any clever ideas how to set this up, given I
have very limited fixtures and tooling, and not a lot of experience with my
machine tools? Thanks.

Photos are at http://www.gatesgarth.com/bore/bore.html

Why not just weld that nut on to extend the threads? Put a bolt and nut
so the nut is just touching the arm and tack it in place. Then turn the
bolt so that you know there is no binding - then finish the weld all
around the outside.

-jim

Chris Wilson wrote:

I have a basic Bridgeport universal mill and a small (8 inch swing)
Harrison lathe. I need to alter some home fabricated lower suspension arms
from a race car. I cut off the stock compliant rubber bushed "eye" from the
arms, and welded in a drilled and tapped buttress to take a rod end. I now
find the geometry of the car has proven to need yet more negative camber.
The rod ends are now threaded right out, so the ends of the threaded shanks
are just flush with the inside walls of the buttresses. I need them about a
quarter of an inch further exttended, and ideally for the rod ends to have
less shank out of the buttress for added safety and strength. I have
decided to bore ou the threaded holes to take a steel tube, internally
threaded 5/8 UNF for the existing rod ends. I am unsure of the best way to
hold the arms to allow me to drill concentrically with the existing
threaded hole to take a sleeve which I envisage as having about a 5mm wall
thickness. This will effectively extend the buttress further outboard, and
the existing rod end will screw into it and use the same type of locknut
against the end of the sleeve. Any clever ideas how to set this up, given I
have very limited fixtures and tooling, and not a lot of experience with my
machine tools? Thanks.

Photos are at http://www.gatesgarth.com/bore/bore.html

On Sat, 28 May 2011 13:57:39 -0500, jim wrote:

Why not just weld that nut on to extend the threads? Put a bolt and nut
so the nut is just touching the arm and tack it in place. Then turn the
bolt so that you know there is no binding - then finish the weld all
around the outside.

-jim

I did consider this Jim, but once the rod end it totally out of the
bulkhead region it's solely held by the weld around the nut. It's a big
heavy old car (Nissan Skyline) and rather than just rely on a peripheral
weld I would be happier if the rod end was in a tube that was supported in
the middle, and welded all round at both ends, if you see what I mean. The
weld a nut on idea is tempting, time and effort wise, though Thanks for
the idea and the post Jim.

On Sat, 28 May 2011 19:31:14 +0100, Chris Wilson
wrote:

I have a basic Bridgeport universal mill and a small (8 inch swing)
Harrison lathe. I need to alter some home fabricated lower suspension arms
from a race car. I cut off the stock compliant rubber bushed "eye" from the
arms, and welded in a drilled and tapped buttress to take a rod end. I now
find the geometry of the car has proven to need yet more negative camber.
The rod ends are now threaded right out, so the ends of the threaded shanks
are just flush with the inside walls of the buttresses. I need them about a
quarter of an inch further exttended, and ideally for the rod ends to have
less shank out of the buttress for added safety and strength. I have
decided to bore ou the threaded holes to take a steel tube, internally
threaded 5/8 UNF for the existing rod ends. I am unsure of the best way to
hold the arms to allow me to drill concentrically with the existing
threaded hole to take a sleeve which I envisage as having about a 5mm wall
thickness. This will effectively extend the buttress further outboard, and
the existing rod end will screw into it and use the same type of locknut
against the end of the sleeve. Any clever ideas how to set this up, given I
have very limited fixtures and tooling, and not a lot of experience with my
machine tools? Thanks.

Photos are at http://www.gatesgarth.com/bore/bore.html

I take it the problem is that arms are too long to set up on the BP
table with the hole axis vertical? If so, clamp the arm to the *front*
of the table with the tail end hanging down towards the floor. If
they're stiil too long, tilt the part and the head.

Or make a friend who owns a right angle head.

Or clamp the arm to your lathe's crosslide and put the tool in the
spindle.

--
Ned Simmons

On May 28, 2:31*pm, Chris Wilson wrote:
I have a basic Bridgeport universal mill and a small (8 inch swing)
Harrison lathe. I need to alter some home fabricated lower suspension arms
from a race car. I cut off the stock compliant rubber bushed "eye" from the
arms, and welded in a drilled and tapped buttress to take a rod end. I now
find the geometry of the car has proven to need yet more negative camber.
The rod ends are now threaded right out, so the ends of the threaded shanks
are just flush with the inside walls of the buttresses. I need them about a
quarter of an inch further exttended, and ideally for the rod ends to have
less shank out of the buttress for added safety and strength. I have
decided to bore ou the threaded holes to take a steel tube, internally
threaded 5/8 UNF for the existing rod ends. I am unsure of the best way to
hold the arms to allow me to drill concentrically with the existing
threaded hole to take a sleeve which I envisage as having about a 5mm wall
thickness. This will effectively extend the buttress further outboard, and
the existing rod end will screw into it and use the same type of locknut
against the end of the sleeve. Any clever ideas how to set this up, given I
have very limited fixtures and tooling, and not a lot of experience with my
machine tools? Thanks.

Photos are athttp://www.gatesgarth.com/bore/bore.html

I read this as asking how to locate the center of the threaded hole.

I would cut the head off a bolt that fits it, screw it into the
threads and chuck the bolt in the drill chuck, then figure out how to
support and clamp the part in that position. You don't want to tighten
the clamps while the bolt is in the chuck, in case the work springs
sideways, but you could loosen the chuck and retract it, then check
alignment after clamping by seeing if it will still slide onto the
bolt shank.

Commercial bolt threads may not be exactly concentric with and
parallel to the shank. If that matters you could indicate the shank
while threading in the bolt.

jsw

On Sun, 29 May 2011 05:09:37 -0700 (PDT), Jim Wilkins
wrote:


Commercial bolt threads may not be exactly concentric with and
parallel to the shank. If that matters you could indicate the shank
while threading in the bolt.

jsw


Just about any bolt that was formed in a thread roller will be
concentric.

Once you cut off the head of course. This means most socket head cap
screws should be the bolts to use.




One could not be a successful Leftwinger without realizing that,
in contrast to the popular conception supported by newspapers
and mothers of Leftwingers, a goodly number of Leftwingers are
not only narrow-minded and dull, but also just stupid.
Gunner Asch