Welding question: reinforce by inner sleeve

Folks - 43-13-1B says an inner sleeve can be up to 1/16th inch smaller
in diameter than the ID of the original tubing.

When you slip the inner tube inside the original tube 1/16th turns
into a lot of slop.

Do you make any attempt to center the inner tube in the original
tubing? If so, how? - Mike

On Wed, 07 Jun 2006 16:00:05 -0400, Michael Horowitz
wrote:

Folks - 43-13-1B says an inner sleeve can be up to 1/16th inch smaller
in diameter than the ID of the original tubing.

When you slip the inner tube inside the original tube 1/16th turns
into a lot of slop.

Do you make any attempt to center the inner tube in the original
tubing? If so, how? - Mike


Simplest method is to slit the tube and expand it to fit snuggly, or
better slit a tube that is too large to fit (like a piece of the tube
being sleeved) and squeeze it down to fit. Then drill both ends being
joined in 2 or 3 places, evenly around the tube, and rosette weld as
well as welding the butt, which can also be scarfed to make a stronger
weld.

--
Posted via a free Usenet account from http://www.teranews.com

On Wed, 07 Jun 2006 17:28:01 -0400, clare at snyder.on.ca wrote:

On Wed, 07 Jun 2006 16:00:05 -0400, Michael Horowitz
wrote:

Folks - 43-13-1B says an inner sleeve can be up to 1/16th inch smaller
in diameter than the ID of the original tubing.

When you slip the inner tube inside the original tube 1/16th turns
into a lot of slop.

Do you make any attempt to center the inner tube in the original
tubing? If so, how? - Mike


Simplest method is to slit the tube and expand it to fit snuggly, or
better slit a tube that is too large to fit (like a piece of the tube
being sleeved) and squeeze it down to fit. Then drill both ends being
joined in 2 or 3 places, evenly around the tube, and rosette weld as
well as welding the butt, which can also be scarfed to make a stronger
weld.


Outstanding! That would solve my problem!

Hate to sound ungrateful but could you point to a reference that
allows this. Please don't take offence, but I'm going to have to
describe what I've done to my supervisory A&P and then to someone with
an IA - Mike

On Wed, 07 Jun 2006 20:25:38 -0400, Michael Horowitz
wrote:

On Wed, 07 Jun 2006 17:28:01 -0400, clare at snyder.on.ca wrote:

On Wed, 07 Jun 2006 16:00:05 -0400, Michael Horowitz
wrote:

Folks - 43-13-1B says an inner sleeve can be up to 1/16th inch smaller
in diameter than the ID of the original tubing.

When you slip the inner tube inside the original tube 1/16th turns
into a lot of slop.

Do you make any attempt to center the inner tube in the original
tubing? If so, how? - Mike


Simplest method is to slit the tube and expand it to fit snuggly, or
better slit a tube that is too large to fit (like a piece of the tube
being sleeved) and squeeze it down to fit. Then drill both ends being
joined in 2 or 3 places, evenly around the tube, and rosette weld as
well as welding the butt, which can also be scarfed to make a stronger
weld.


Outstanding! That would solve my problem!

Hate to sound ungrateful but could you point to a reference that
allows this. Please don't take offence, but I'm going to have to
describe what I've done to my supervisory A&P and then to someone with
an IA - Mike
I think it is called out in AC134. It is also in an old tome called
Airplane and Engine Maintenance for the Airplane Mechanic, by Brimm
and Boggess published in 1936 on page 201, reference figure IV.

For rosette welds, only the OUTER tube is drilled. A scarfed or
fishmouthed joint is called for in this refference rather than a
straight butt joint.

If you want the job to be easier to inspect, keep a sufficient gap
between the ends that it is possible for the inspector to tell you
have good penetration into the sleave. If you do this you will also
want to weld the slit in the sleave.

A simpler, but messier looking repair is using the sleave on the
OUTSIDE of the tube..

--
Posted via a free Usenet account from http://www.teranews.com

clare wrote:
On Wed, 07 Jun 2006 20:25:38 -0400, Michael Horowitz
wrote:

On Wed, 07 Jun 2006 17:28:01 -0400, clare at snyder.on.ca wrote:

On Wed, 07 Jun 2006 16:00:05 -0400, Michael Horowitz
wrote:

Folks - 43-13-1B says an inner sleeve can be up to 1/16th inch smaller
in diameter than the ID of the original tubing.

When you slip the inner tube inside the original tube 1/16th turns
into a lot of slop.

Do you make any attempt to center the inner tube in the original
tubing? If so, how? - Mike


Simplest method is to slit the tube and expand it to fit snuggly, or
better slit a tube that is too large to fit (like a piece of the tube
being sleeved) and squeeze it down to fit. Then drill both ends being
joined in 2 or 3 places, evenly around the tube, and rosette weld as
well as welding the butt, which can also be scarfed to make a stronger
weld.


Outstanding! That would solve my problem!

Hate to sound ungrateful but could you point to a reference that
allows this. Please don't take offence, but I'm going to have to
describe what I've done to my supervisory A&P and then to someone with
an IA - Mike
I think it is called out in AC134. It is also in an old tome called
Airplane and Engine Maintenance for the Airplane Mechanic, by Brimm
and Boggess published in 1936 on page 201, reference figure IV.

For rosette welds, only the OUTER tube is drilled. A scarfed or
fishmouthed joint is called for in this refference rather than a
straight butt joint.

If you want the job to be easier to inspect, keep a sufficient gap
between the ends that it is possible for the inspector to tell you
have good penetration into the sleave. If you do this you will also
want to weld the slit in the sleave.

A simpler, but messier looking repair is using the sleave on the
OUTSIDE of the tube..

--


Did you mean AC 43-13-1B? Rewelding a piece of tubing is discussed when
doing an external splice to streamlined tubing for sure, but I'm not
sure splitting and rewelding an _inner_ sleeve is discussed.

For a variety of reasons this should be a smooth repair - Mike

FYI - I talked with an IA on the splitting of tube to reduce its
diameter. He said nothing doing on a certificated aircraft. - Mike



On Wed, 07 Jun 2006 22:32:10 -0400, clare at snyder.on.ca wrote:

On Wed, 07 Jun 2006 20:25:38 -0400, Michael Horowitz
wrote:

On Wed, 07 Jun 2006 17:28:01 -0400, clare at snyder.on.ca wrote:

On Wed, 07 Jun 2006 16:00:05 -0400, Michael Horowitz
wrote:

Folks - 43-13-1B says an inner sleeve can be up to 1/16th inch smaller
in diameter than the ID of the original tubing.

When you slip the inner tube inside the original tube 1/16th turns
into a lot of slop.

Do you make any attempt to center the inner tube in the original
tubing? If so, how? - Mike


Simplest method is to slit the tube and expand it to fit snuggly, or
better slit a tube that is too large to fit (like a piece of the tube
being sleeved) and squeeze it down to fit. Then drill both ends being
joined in 2 or 3 places, evenly around the tube, and rosette weld as
well as welding the butt, which can also be scarfed to make a stronger
weld.


Outstanding! That would solve my problem!

Hate to sound ungrateful but could you point to a reference that
allows this. Please don't take offence, but I'm going to have to
describe what I've done to my supervisory A&P and then to someone with
an IA - Mike
I think it is called out in AC134. It is also in an old tome called
Airplane and Engine Maintenance for the Airplane Mechanic, by Brimm
and Boggess published in 1936 on page 201, reference figure IV.

For rosette welds, only the OUTER tube is drilled. A scarfed or
fishmouthed joint is called for in this refference rather than a
straight butt joint.

If you want the job to be easier to inspect, keep a sufficient gap
between the ends that it is possible for the inspector to tell you
have good penetration into the sleave. If you do this you will also
want to weld the slit in the sleave.

A simpler, but messier looking repair is using the sleave on the
OUTSIDE of the tube..

On Sat, 10 Jun 2006 19:52:06 -0400, Michael Horowitz
wrote:

FYI - I talked with an IA on the splitting of tube to reduce its
diameter. He said nothing doing on a certificated aircraft. - Mike


splitting the original tube I can understand, but splitting the insert
tube, especially if it is welded up again. huh?

the trouble in repair work is that if the guy has little appreciation
of structural engineering and the actual forces the part will see in
service quite often you will see a lapse into a position of comfort
that may only be held because it has never been tested.

very frustrating.

maybe try a grab bag of tube scraps from Aircraft Spruce to see
whether you get a useable piece.

Stealth Pilot

Structural tube sizes are usually 5/8" or larger, which are
available in 0.120" wall thickness. Buy 0.120" wall in the same
diameter as the tube you're splicing, chuck it in the lathe, turn it to
the desired slip fit OD.

Dan Horton