I need to put a smooth finish on the inside of some aluminum tube. 1"
ID smallest - 2" ID biggest. Same application different sizes. If it
was steel or cast iron I would just run a brake hone or cylinder hone
down it, but I think the stones would just pack up with aluminum if I
tried that with this. It doesn't need to be precise, just smooth. I
want to round off the weld seam (not to bad to begin with) and make it
fairly shiny inside. Flap wheels? Buffing wheel with a "course"
substitute for rouge? Other?

On Apr 13, 12:08*pm, Bob La Londe wrote:
I need to put a smooth finish on the inside of some aluminum tube. *1"
ID smallest - 2" ID biggest. *Same application different sizes. *If it
was steel or cast iron I would just run a brake hone or cylinder hone
down it, but I think the stones would just pack up with aluminum if I
tried that with this. *It doesn't need to be precise, just smooth. *I
want to round off the weld seam (not to bad to begin with) and make it
fairly shiny inside. *Flap wheels? *Buffing wheel with a "course"
substitute for rouge? *Other?

Needs more info about your tubes but....Ball Sizing?
Pressing a hard ball through the tube. Expands and smoothes the ID.

Bal-Tec's site explains the process.
http://www.precisionballs.com/index.php

HTH,
PaulS

"Bob La Londe" wrote in message
...
I need to put a smooth finish on the inside of some aluminum tube. 1"
ID smallest - 2" ID biggest. Same application different sizes. If it
was steel or cast iron I would just run a brake hone or cylinder hone
down it, but I think the stones would just pack up with aluminum if I
tried that with this. It doesn't need to be precise, just smooth. I
want to round off the weld seam (not to bad to begin with) and make it
fairly shiny inside. Flap wheels? Buffing wheel with a "course"
substitute for rouge? Other?



I have actually tried this on the inside of a half cylinder of aluminum for
optical purposes. With aluminum, smooth and shiny are not the same thing.
Aluminum has a very hard outer oxide surface layer. As you sand, you break
through parts of that and then gouge the soft metal underneath while the
remaining oxide protects other areas. Even fine grits will give a gray
pitted surface, although maybe thats shiny enough for what you want. The
easiest way to get moderately shiny, but not so smooth surface is careful
machining with kerosene.

If you want smooth and mirror shiny, I used a gradual progression of silicon
carbide paper down to 3000 grit with kerosene which supposedly prevents
forming new oxide. I then used red rouge on a soft buff for final polish,
but that is because that is what I had.

If you look on youtube, people have posted all sorts of particular methods
of polishing aluminum with all sorts of compounds, but they are all
tedious.

On Apr 13, 12:08*pm, Bob La Londe wrote:
I need to put a smooth finish on the inside of some aluminum tube. *1"
ID smallest - 2" ID biggest. *Same application different sizes. *If it
was steel or cast iron I would just run a brake hone or cylinder hone
down it, but I think the stones would just pack up with aluminum if I
tried that with this. *It doesn't need to be precise, just smooth. *I
want to round off the weld seam (not to bad to begin with) and make it
fairly shiny inside. *Flap wheels? *Buffing wheel with a "course"
substitute for rouge? *Other?

Weld seam might be best handled with a straight reamer if it's sizable.

"Bob La Londe" wrote in message
...
I need to put a smooth finish on the inside of some aluminum tube. 1"
ID smallest - 2" ID biggest. Same application different sizes. If it
was steel or cast iron I would just run a brake hone or cylinder hone
down it, but I think the stones would just pack up with aluminum if I
tried that with this. It doesn't need to be precise, just smooth. I
want to round off the weld seam (not to bad to begin with) and make it
fairly shiny inside. Flap wheels? Buffing wheel with a "course"
substitute for rouge? Other?

Ok shiny was probably not the best term. Smooth is more important. It will
have a low pressure pneumatic seal with am o-ring and piston. The raw tube
works ok, but I was thinking with a better than mill finish the o-rings
might last longer.

So far I have not worn out an o-ring with the existing units, but I would
like to make future ones "better."

"Bob La Londe" fired this volley in
:


Ok shiny was probably not the best term. Smooth is more important.
It will have a low pressure pneumatic seal with am o-ring and piston.
The raw tube works ok, but I was thinking with a better than mill
finish the o-rings might last longer.

So far I have not worn out an o-ring with the existing units, but I
would like to make future ones "better."

How long are these tubes, Bob?

It takes darned near forever with a long boring bar, but with the right
speeds and the right rake on an HSS boring bit, you can get a pretty nice
finish.

Get it turned to "round" (sans weld), then use a small flap hone if you
want to clean it up.

Remember, I went through this recently with a customer's project, and
finally ended up buying an aluminum air cylinder long enough to cut what
I needed. But mine was 18" long and 6" i.d. That made it kind of hard
to bore with a conventional setup, and I didn't have the time to jig the
lathe to mount the work on the cross-slide, and the bit in the spindle,
supported by the tailstock.

LLoyd

On Fri, 13 Apr 2012 09:08:59 -0700 (PDT), Bob La Londe
wrote:

I need to put a smooth finish on the inside of some aluminum tube. 1"
ID smallest - 2" ID biggest. Same application different sizes. If it
was steel or cast iron I would just run a brake hone or cylinder hone
down it, but I think the stones would just pack up with aluminum if I
tried that with this. It doesn't need to be precise, just smooth. I
want to round off the weld seam (not to bad to begin with) and make it
fairly shiny inside. Flap wheels? Buffing wheel with a "course"
substitute for rouge? Other?

You have a lot of variables and compromises in there, which I'll leave
to others to deal with. I haven't done what you're trying to do.

But this is a good excuse to bring up a related article that may be of
some use to other aluminum honers, especially anyone working on model
engines. These capital-heavy industrial methods may not be directly
applicable but it should be a help to see what industrial users are
dealing with when they hone hyper-eutectic aluminum:

http://www.sunnen.com/newsdetails.aspx?newsid=11

Here's more good stuff on honing aluminum from Sunnen:

http://db1.spiderline.com/exec/searc...minum&a=100810

--
Ed Huntress

Bob La Londe wrote:
I need to put a smooth finish on the inside of some aluminum tube. 1"
ID smallest - 2" ID biggest. Same application different sizes. If it
was steel or cast iron I would just run a brake hone or cylinder hone
down it, but I think the stones would just pack up with aluminum if I
tried that with this. It doesn't need to be precise, just smooth. I
want to round off the weld seam (not to bad to begin with) and make it
fairly shiny inside. Flap wheels? Buffing wheel with a "course"
substitute for rouge? Other?








I think I may have seen aluminium tube with a weld seam but rarely, the
stuff I normally get in the size range you mention is extruded so no
weld seam. I there a reason why you can't get what you need without the
seam.

"David Billington" wrote in message
...
Bob La Londe wrote:
I need to put a smooth finish on the inside of some aluminum tube. 1"
ID smallest - 2" ID biggest. Same application different sizes. If it
was steel or cast iron I would just run a brake hone or cylinder hone
down it, but I think the stones would just pack up with aluminum if I
tried that with this. It doesn't need to be precise, just smooth. I
want to round off the weld seam (not to bad to begin with) and make it
fairly shiny inside. Flap wheels? Buffing wheel with a "course"
substitute for rouge? Other?








I think I may have seen aluminium tube with a weld seam but rarely, the
stuff I normally get in the size range you mention is extruded so no weld
seam. I there a reason why you can't get what you need without the seam.

The seam really is not a major issue. The over all smoothness of the
interior bore is what's important.

"Lloyd E. Sponenburgh" lloydspinsidemindspring.com wrote in message
. 3.70...
"Bob La Londe" fired this volley in
:


Ok shiny was probably not the best term. Smooth is more important.
It will have a low pressure pneumatic seal with am o-ring and piston.
The raw tube works ok, but I was thinking with a better than mill
finish the o-rings might last longer.

So far I have not worn out an o-ring with the existing units, but I
would like to make future ones "better."

How long are these tubes, Bob?

Finished working length may vary from 10-12 inches.

It takes darned near forever with a long boring bar, but with the right
speeds and the right rake on an HSS boring bit, you can get a pretty nice
finish.

Yeah, I thought about a round face boring bit, but supporting and doing a
12" internal finish is beyond my skills and equipment. I was just hoping to
improve the finish "some"

Get it turned to "round" (sans weld), then use a small flap hone if you
want to clean it up.

I may "just" do a flap wheel down the bore and see how that works out.
perfectly round is not super critical. it's a low pressure o-ring fit after
all.

Remember, I went through this recently with a customer's project, and
finally ended up buying an aluminum air cylinder long enough to cut what
I needed. But mine was 18" long and 6" i.d. That made it kind of hard
to bore with a conventional setup, and I didn't have the time to jig the
lathe to mount the work on the cross-slide, and the bit in the spindle,
supported by the tailstock.


I recall your project. I read quite a bit on that thread. Glad you got it
worked out.


Bob

On Apr 13, 10:08*am, Bob La Londe wrote:
I need to put a smooth finish on the inside of some aluminum tube. *1"
ID smallest - 2" ID biggest. *Same application different sizes. *If it
was steel or cast iron I would just run a brake hone or cylinder hone
down it, but I think the stones would just pack up with aluminum if I
tried that with this. *It doesn't need to be precise, just smooth. *I
want to round off the weld seam (not to bad to begin with) and make it
fairly shiny inside. *Flap wheels? *Buffing wheel with a "course"
substitute for rouge? *Other?

If you've got a ridge, I'd either do ball sizing or get a helical
reamer to get rid of it. If you need to improve the surface finish,
ream a little larger, then use a lead lap on it. You need a lap
surface softer than the metal you're trying to lap. And like the
other guy said, I've not seen aluminum tubing with weld seams, all
I've seen has been extruded. If you could get that sort of thing in
the sizes you need, you'd be ahead of the game.

Stan

On Fri, 13 Apr 2012 13:18:27 -0700, Bob La Londe wrote:

"Lloyd E. Sponenburgh" lloydspinsidemindspring.com wrote in message
. 3.70...
"Bob La Londe" fired this volley in
:


Ok shiny was probably not the best term. Smooth is more important. It
will have a low pressure pneumatic seal with am o-ring and piston. The
raw tube works ok, but I was thinking with a better than mill finish
the o-rings might last longer.

So far I have not worn out an o-ring with the existing units, but I
would like to make future ones "better."

How long are these tubes, Bob?

Finished working length may vary from 10-12 inches.

It takes darned near forever with a long boring bar, but with the right
speeds and the right rake on an HSS boring bit, you can get a pretty
nice finish.

Yeah, I thought about a round face boring bit, but supporting and doing
a 12" internal finish is beyond my skills and equipment. I was just
hoping to improve the finish "some"

Get it turned to "round" (sans weld), then use a small flap hone if you
want to clean it up.

I may "just" do a flap wheel down the bore and see how that works out.
perfectly round is not super critical. it's a low pressure o-ring fit
after all.

Remember, I went through this recently with a customer's project, and
finally ended up buying an aluminum air cylinder long enough to cut
what I needed. But mine was 18" long and 6" i.d. That made it kind of
hard to bore with a conventional setup, and I didn't have the time to
jig the lathe to mount the work on the cross-slide, and the bit in the
spindle, supported by the tailstock.


I recall your project. I read quite a bit on that thread. Glad you got
it worked out.


Bob

I think that if the seam on the inside is very big, doing your flapwheel
alone is going to be very disappointing.

I would either try to do a boring bar mounted on the cross-slide, with
center rest to hold the tube in place, or mount the tube on the cross
slide and run it past a boring bar that's spinning on the lathe, with
center rest fixed to the lathe base somehow, or I would make a boring bar
with a pilot that runs down the inside of the current tube (avoiding the
seam) and shaves everything evenly.

I suspect the piloted boring bar would be the closest to being within my
abilities, and it certainly matches the drawer full of 50-year-old ball
bearing sets that I inherited from my uncle. I don't know what would
work for you.

I'd bore it out, then look at polishing it with whatever 'soft' tools
came to hand.

But first, I'd look for seamless tubing.

--
My liberal friends think I'm a conservative kook.
My conservative friends think I'm a liberal kook.
Why am I not happy that they have found common ground?

Tim Wescott, Communications, Control, Circuits & Software
http://www.wescottdesign.com

On Apr 13, 1:26*pm, "Bob La Londe" wrote:

Ok shiny was probably not the best term. *Smooth is more important. *It will
have a low pressure pneumatic seal with am o-ring and piston. *The raw tube
works ok, but I was thinking with a better than mill finish the o-rings
might last longer.

So far I have not worn out an o-ring with the existing units, but I would
like to make future ones "better."

Paul Schiller has the right idea. Ball size. MSC sells 10 1 inch
balls for $13.6x . So not too expensive to try it. The 2 inch dia
balls are not so cheap.

Dan

On Fri, 13 Apr 2012 13:13:59 -0700, "Bob La Londe"
wrote:

"David Billington" wrote in message
.. .
Bob La Londe wrote:
I need to put a smooth finish on the inside of some aluminum tube. 1"
ID smallest - 2" ID biggest. Same application different sizes. If it
was steel or cast iron I would just run a brake hone or cylinder hone
down it, but I think the stones would just pack up with aluminum if I
tried that with this. It doesn't need to be precise, just smooth. I
want to round off the weld seam (not to bad to begin with) and make it
fairly shiny inside. Flap wheels? Buffing wheel with a "course"
substitute for rouge? Other?








I think I may have seen aluminium tube with a weld seam but rarely, the
stuff I normally get in the size range you mention is extruded so no weld
seam. I there a reason why you can't get what you need without the seam.

The seam really is not a major issue. The over all smoothness of the
interior bore is what's important.


Why not just use the cylinder hones, that you mentioned, with kerosene
flood cooling/lube. Should keep the stones clean.


Cheers,

John B.

How many parts?
One or two, no idea.
Many? Roller burnisher.
Greg O

On Sat, 14 Apr 2012 16:49:57 -0500, "Greg O"
wrote:

How many parts?
One or two, no idea.
Many? Roller burnisher.
Greg O

Neither ball sizing or roller burnishing is appropriate for thin
tubes.

I was waiting to see the wall thickness before commenting, based on
industry practice rather than my own experience, but I either missed
it or it hasn't been stated.

We did a lot of roller burnishing when I was at Wasino. You need some
resistance to make it work. I don't think it would iron out a weld
seam, regardless. It's used to size and to flatten the peaks of the
bore's surface finish.

Similarly, ball sizing. Unless those tube walls are quite thick, I
can't see it ironing out a weld seam. It probably would just locally
stretch the tube, unless the tube has very thick walls. That doesn't
seem likely if it's seam-welded.

--
Ed Huntress

"Gunner Asch" wrote in message
news
On Fri, 13 Apr 2012 10:26:40 -0700, "Bob La Londe"
wrote:

"Bob La Londe" wrote in message
...
I need to put a smooth finish on the inside of some aluminum tube. 1"
ID smallest - 2" ID biggest. Same application different sizes. If it
was steel or cast iron I would just run a brake hone or cylinder hone
down it, but I think the stones would just pack up with aluminum if I
tried that with this. It doesn't need to be precise, just smooth. I
want to round off the weld seam (not to bad to begin with) and make it
fairly shiny inside. Flap wheels? Buffing wheel with a "course"
substitute for rouge? Other?

Ok shiny was probably not the best term. Smooth is more important. It
will
have a low pressure pneumatic seal with am o-ring and piston. The raw
tube
works ok, but I was thinking with a better than mill finish the o-rings
might last longer.

So far I have not worn out an o-ring with the existing units, but I would
like to make future ones "better."

The ball method..at a steady speed.

Or a cylinder hone (which is what I would use)

You don't think the stones will plug up with aluminum?

"Ed Huntress" wrote in message
...
On Sat, 14 Apr 2012 16:49:57 -0500, "Greg O"
wrote:

How many parts?
One or two, no idea.
Many? Roller burnisher.
Greg O

Neither ball sizing or roller burnishing is appropriate for thin
tubes.

I was waiting to see the wall thickness before commenting, based on
industry practice rather than my own experience, but I either missed
it or it hasn't been stated.

We did a lot of roller burnishing when I was at Wasino. You need some
resistance to make it work. I don't think it would iron out a weld
seam, regardless. It's used to size and to flatten the peaks of the
bore's surface finish.

Similarly, ball sizing. Unless those tube walls are quite thick, I
can't see it ironing out a weld seam. It probably would just locally
stretch the tube, unless the tube has very thick walls. That doesn't
seem likely if it's seam-welded.

..125" wall thickness.

"Bob La Londe" fired this volley in news:6Hrir.1512
:

You don't think the stones will plug up with aluminum?

Maybe not, if the whole affair is lubricated with kerosene, and fresh is
kept pouring through the tube while honing is going on.

On Sat, 14 Apr 2012 20:59:42 -0700, "Bob La Londe"
wrote:

"Ed Huntress" wrote in message
.. .
On Sat, 14 Apr 2012 16:49:57 -0500, "Greg O"
wrote:

How many parts?
One or two, no idea.
Many? Roller burnisher.
Greg O

Neither ball sizing or roller burnishing is appropriate for thin
tubes.

I was waiting to see the wall thickness before commenting, based on
industry practice rather than my own experience, but I either missed
it or it hasn't been stated.

We did a lot of roller burnishing when I was at Wasino. You need some
resistance to make it work. I don't think it would iron out a weld
seam, regardless. It's used to size and to flatten the peaks of the
bore's surface finish.

Similarly, ball sizing. Unless those tube walls are quite thick, I
can't see it ironing out a weld seam. It probably would just locally
stretch the tube, unless the tube has very thick walls. That doesn't
seem likely if it's seam-welded.

.125" wall thickness.

Then I'm skeptical that ball sizing or roller burnishing would iron
out the weld. They'd probably just distort the tube.

--
Ed Huntress

On Sat, 14 Apr 2012 20:57:48 -0700, "Bob La Londe"
wrote:

"Gunner Asch" wrote in message
news
On Fri, 13 Apr 2012 10:26:40 -0700, "Bob La Londe"
wrote:

"Bob La Londe" wrote in message
...
I need to put a smooth finish on the inside of some aluminum tube. 1"
ID smallest - 2" ID biggest. Same application different sizes. If it
was steel or cast iron I would just run a brake hone or cylinder hone
down it, but I think the stones would just pack up with aluminum if I
tried that with this. It doesn't need to be precise, just smooth. I
want to round off the weld seam (not to bad to begin with) and make it
fairly shiny inside. Flap wheels? Buffing wheel with a "course"
substitute for rouge? Other?

Ok shiny was probably not the best term. Smooth is more important. It
will
have a low pressure pneumatic seal with am o-ring and piston. The raw
tube
works ok, but I was thinking with a better than mill finish the o-rings
might last longer.

So far I have not worn out an o-ring with the existing units, but I would
like to make future ones "better."

The ball method..at a steady speed.

Or a cylinder hone (which is what I would use)

You don't think the stones will plug up with aluminum?

Not if you hone wet. I've honed a lot of aluminum brake cyls. Just
keep the stones wet. Varsol or brake fluid.

On Sun, 15 Apr 2012 11:58:07 -0400, wrote:

On Sat, 14 Apr 2012 20:57:48 -0700, "Bob La Londe"
wrote:

"Gunner Asch" wrote in message
news
On Fri, 13 Apr 2012 10:26:40 -0700, "Bob La Londe"
wrote:

"Bob La Londe" wrote in message
...
I need to put a smooth finish on the inside of some aluminum tube. 1"
ID smallest - 2" ID biggest. Same application different sizes. If it
was steel or cast iron I would just run a brake hone or cylinder hone
down it, but I think the stones would just pack up with aluminum if I
tried that with this. It doesn't need to be precise, just smooth. I
want to round off the weld seam (not to bad to begin with) and make it
fairly shiny inside. Flap wheels? Buffing wheel with a "course"
substitute for rouge? Other?

Ok shiny was probably not the best term. Smooth is more important. It
will
have a low pressure pneumatic seal with am o-ring and piston. The raw
tube
works ok, but I was thinking with a better than mill finish the o-rings
might last longer.

So far I have not worn out an o-ring with the existing units, but I would
like to make future ones "better."

The ball method..at a steady speed.

Or a cylinder hone (which is what I would use)

You don't think the stones will plug up with aluminum?

Not if you hone wet. I've honed a lot of aluminum brake cyls. Just
keep the stones wet. Varsol or brake fluid.

And use silicon carbide stones, rather than aluminum oxide.

--
Ed Huntress

"Gunner Asch" wrote in
message
...
On Sat, 14 Apr 2012 20:57:48 -0700, "Bob La
Londe"
wrote:

"Gunner Asch" wrote in
message
news
On Fri, 13 Apr 2012 10:26:40 -0700, "Bob La
Londe"
wrote:

"Bob La Londe"
wrote in message
...
I need to put a smooth finish on the inside
of some aluminum tube. 1"
ID smallest - 2" ID biggest. Same
application different sizes. If it
was steel or cast iron I would just run a
brake hone or cylinder hone
down it, but I think the stones would just
pack up with aluminum if I
tried that with this. It doesn't need to be
precise, just smooth. I
want to round off the weld seam (not to bad
to begin with) and make it
fairly shiny inside. Flap wheels? Buffing
wheel with a "course"
substitute for rouge? Other?

Ok shiny was probably not the best term.
Smooth is more important. It
will
have a low pressure pneumatic seal with am
o-ring and piston. The raw
tube
works ok, but I was thinking with a better
than mill finish the o-rings
might last longer.

So far I have not worn out an o-ring with the
existing units, but I would
like to make future ones "better."

The ball method..at a steady speed.

Or a cylinder hone (which is what I would use)

You don't think the stones will plug up with
aluminum?

Not if you apply liberal amounts of kerosene and
dont try to take off
huge amounts at one time. If anything..it will
tend to burnish the
thing into being round. Shrug

I see lots of aluminum parts being honed on
Sunnen hones every day in
machne shops. They just dont try to take off
many thousands at one time.

Gunner

Using a hone to remove weld irregularities will
result in an oval cylinder.
When the stones contact the weld there is also
contact with the opposite
side. As the weld is cut so is the area opposite
which you don't want to
happen. Is this weld longitudinal or
circumferential? Try to only cut
the problem area with perhaps a piloted scraper as
another poster
suggested. If the weld is circum. then maybe an
expanding pilot
with a rotating cutter?
Going back to the oval cylinder, I've seen this
happen with small engine
cylinders where a guy tried to hone out aluminum
smears with a hone.
As the hone worked on the smears it also cut the
opposite side and
gave an oval hole out of spec. What I do with
these smears is use
sodium hydroxide and room temp water. Lay the cyl
horizontal and
work on one area at a time and it will remove all
of it. Then hone......
phil k.

"Bob La Londe" wrote in message
...
"Ed Huntress" wrote in message
...
On Sat, 14 Apr 2012 16:49:57 -0500, "Greg O"
wrote:

How many parts?
One or two, no idea.
Many? Roller burnisher.
Greg O

Neither ball sizing or roller burnishing is appropriate for thin
tubes.

I was waiting to see the wall thickness before commenting, based on
industry practice rather than my own experience, but I either missed
it or it hasn't been stated.

We did a lot of roller burnishing when I was at Wasino. You need some
resistance to make it work. I don't think it would iron out a weld
seam, regardless. It's used to size and to flatten the peaks of the
bore's surface finish.

Similarly, ball sizing. Unless those tube walls are quite thick, I
can't see it ironing out a weld seam. It probably would just locally
stretch the tube, unless the tube has very thick walls. That doesn't
seem likely if it's seam-welded.

.125" wall thickness.

Lathe jaws machined to match the OD, take a light pass with a boring bar to
remove the weld, and roller burnish.
A hone will work too, but the roller burnisher will give a much smoother
finish.

I have bore many aluminum small engine blocks .010" over size with a Sunnen
hone with AN 500 stones and Sunnen's honing oil.

Either way you will need to get the cylinder cleaned up before any type of
finish can be done.
GregO