Cutting sheet steel

On Tue, 25 Nov 2003 03:04:45 GMT, Ernest Christley
wrote:

I've got some .035 4130 that I have to cut elevon ribs from.

Are there any better options?

--
http://www.ernest.isa-geek.org/
"Ignorance is mankinds normal state,
alleviated by information and experience."
Veeduber


Veedubber,

One of the easiest ways to cut sheet 4130 is with a band saw. Use an
old metal cutting blade installed upside down (the teeth pointing up).
Run the saw at normal speed and feed in the material. Keep the
pressure up and it will go (melt) through like you are cutting butter.
Don't pause though, it is not so easy to get started again. Some have
also used the back side of the blade for this purpose with success.

O-ring Seals

One of the easiest ways to cut sheet 4130 is with a band saw. Use an
old metal cutting blade installed upside down (the teeth pointing up).
Run the saw at normal speed and feed in the material. Keep the
pressure up and it will go (melt) through like you are cutting butter.
Don't pause though, it is not so easy to get started again. Some have
also used the back side of the blade for this purpose with success.

O-ring Seals

---------------------------------------------------

Dear O-ring (and the Group),

I believe you'll find there's a bit more to it than that :-)

First off, the 'normal speed' you're referring to is for a woodworking bandsaw.
The down-side is that most woodworking bandsaws are fitted with a rubber
'tire' on their driver- & idler-wheels. Friction cutting steel (which is what
you're doing) will destroy the tire on the driver-wheel in short order.
Bandsaw tires are moderately expensive and can be hellishly difficult to
replace on some saws.

Metal-cutting bandsaws do not use tires. The wheels are sizes so that the
teeth overhang the edge of the wheel, not only for cooling but for clearing the
swarf.

You can set-up a metal cutting bandsaw for friction cutting if you have the
proper ratio pulleys (ie, increase the blade speed).

The popularity of this method hinged largely on the builder's ability to splice
their own blades because the original idea was to use common steel strapping.
Operated at high speed -- and cutting relatively thin stock -- the stuff does
in fact cut like butter, with a very attractive displace of sparks, too :-)
But the strapping was rapidly consumed and unless you were a dab hand at
splicing, ideally with a Do-All type butt-welder, there was no long-term
advantage over regular cutting.

All of this came about due to the difficulty of cutting relatively hard steel
in thinner gauges, which loves to strip the teeth off anything. .035 4130, you
can do pretty well using a regular bi-metallic 32T blade by simply rigging the
work to feed 'downhill' so that two teeth are in contact with the work.

I've responded to your message because it appeared to be addressed to me, even
though I was not the person who posted the original question. Someone else has
already offered the most practical solution, which is to track down a
stomp-shear and just whack those puppies out. But the fellow posting the
question implied he not only wanted to make the part but that he wanted to
acquire the tool, learn to use it, and make the parts himself. In that light I
thought telling him to buy a shear might be a bit much :-) ...but did mention
several other methods & tools for producing the parts. I think I even
mentioned bandsawing but I assumed he would know I meant with a metal-cutting
bandsaw.

Friction cutting is kind of fun but if your only means of splicing a blade is
to taper the piece and use hard solder, I think you'll find you can't use
strapping. Too thin; the splice fails due to the heat. And if you can't use
strapping I don't see much sense in ruining a good blade, unless you're trying
to cut 6xxx stock or a leaf spring or something like that and friction cutting
is your only option. Personally, I'd just whip out my phasor, give them
Klingons hell :-)

-R.S.Hoover

On 26 Nov 2003 02:52:25 GMT, (Veeduber) wrote:

Thanks RS for the additional information. Sorry, the post was not
intended for you that is just how it came out in the thread. In my
experience, and I have been doing this technique off and on for over
20 years, is that it has not harmed the tires on my old Craftsman wood
cutting band saw. I am not advocating using a "good" blade for this.
Many of us have sufficient old dull blades around for this purpose. I
tend to wear out blades rather than break them.

O-ring
--------------------------------------------------

Dear O-ring (and the Group),

I believe you'll find there's a bit more to it than that :-)

First off, the 'normal speed' you're referring to is for a woodworking bandsaw.
The down-side is that most woodworking bandsaws are fitted with a rubber
'tire' on their driver- & idler-wheels. Friction cutting steel (which is what
you're doing) will destroy the tire on the driver-wheel in short order.
Bandsaw tires are moderately expensive and can be hellishly difficult to
replace on some saws.

Metal-cutting bandsaws do not use tires. The wheels are sizes so that the
teeth overhang the edge of the wheel, not only for cooling but for clearing the
swarf.

You can set-up a metal cutting bandsaw for friction cutting if you have the
proper ratio pulleys (ie, increase the blade speed).

The popularity of this method hinged largely on the builder's ability to splice
their own blades because the original idea was to use common steel strapping.
Operated at high speed -- and cutting relatively thin stock -- the stuff does
in fact cut like butter, with a very attractive displace of sparks, too :-)
But the strapping was rapidly consumed and unless you were a dab hand at
splicing, ideally with a Do-All type butt-welder, there was no long-term
advantage over regular cutting.

All of this came about due to the difficulty of cutting relatively hard steel
in thinner gauges, which loves to strip the teeth off anything. .035 4130, you
can do pretty well using a regular bi-metallic 32T blade by simply rigging the
work to feed 'downhill' so that two teeth are in contact with the work.

I've responded to your message because it appeared to be addressed to me, even
though I was not the person who posted the original question. Someone else has
already offered the most practical solution, which is to track down a
stomp-shear and just whack those puppies out. But the fellow posting the
question implied he not only wanted to make the part but that he wanted to
acquire the tool, learn to use it, and make the parts himself. In that light I
thought telling him to buy a shear might be a bit much :-) ...but did mention
several other methods & tools for producing the parts. I think I even
mentioned bandsawing but I assumed he would know I meant with a metal-cutting
bandsaw.

Friction cutting is kind of fun but if your only means of splicing a blade is
to taper the piece and use hard solder, I think you'll find you can't use
strapping. Too thin; the splice fails due to the heat. And if you can't use
strapping I don't see much sense in ruining a good blade, unless you're trying
to cut 6xxx stock or a leaf spring or something like that and friction cutting
is your only option. Personally, I'd just whip out my phasor, give them
Klingons hell :-)

-R.S.Hoover

snipped
Operated at high speed -- and cutting relatively thin stock -- the stuff does
in fact cut like butter, with a very attractive displace of sparks, too :-)
snipped

As a Tool&Die shop owner for many years, I have friction-sawed a lot of
different materials and it is the only way to go when cutting stainless steel.

Your post was excellent and I would like to add one thing;
ASAP Aircraft Co., years ago, had some small, flat parts laser cut. Later, the
edges of the parts began showing small cracks caused by the intense heat of the
laser and they stopped using that method of cutting.
Friction sawing also produces heat. In fact, it melts the material.
I dont know if this would be a problem or not but I think I would normalize the
parts. Just to be on the safe side.

Warren

(Veeduber) wrote in message ...
One of the easiest ways to cut sheet 4130 is with a band saw. Use an
old metal cutting blade installed upside down (the teeth pointing up).
Run the saw at normal speed and feed in the material. Keep the
pressure up and it will go (melt) through like you are cutting butter.
Don't pause though, it is not so easy to get started again. Some have
also used the back side of the blade for this purpose with success.

O-ring Seals

---------------------------------------------------

Dear O-ring (and the Group),

I believe you'll find there's a bit more to it than that :-)

First off, the 'normal speed' you're referring to is for a woodworking bandsaw.
The down-side is that most woodworking bandsaws are fitted with a rubber
'tire' on their driver- & idler-wheels. Friction cutting steel (which is what
you're doing) will destroy the tire on the driver-wheel in short order.
Bandsaw tires are moderately expensive and can be hellishly difficult to
replace on some saws.

Metal-cutting bandsaws do not use tires. The wheels are sizes so that the
teeth overhang the edge of the wheel, not only for cooling but for clearing the
swarf.

You can set-up a metal cutting bandsaw for friction cutting if you have the
proper ratio pulleys (ie, increase the blade speed).

The popularity of this method hinged largely on the builder's ability to splice
their own blades because the original idea was to use common steel strapping.
Operated at high speed -- and cutting relatively thin stock -- the stuff does
in fact cut like butter, with a very attractive displace of sparks, too :-)
But the strapping was rapidly consumed and unless you were a dab hand at
splicing, ideally with a Do-All type butt-welder, there was no long-term
advantage over regular cutting.

All of this came about due to the difficulty of cutting relatively hard steel
in thinner gauges, which loves to strip the teeth off anything. .035 4130, you
can do pretty well using a regular bi-metallic 32T blade by simply rigging the
work to feed 'downhill' so that two teeth are in contact with the work.


I used to cut 4130 using the bandsaw method, with a 1/2" bimetal
blade installed the right way, and just letting the teeth round off
the first time I used it. It would cut rather nicely, and didn't hurt
the rubber tire. Keeping the cut straight was the biggest hassle.
There's a German-made friction-cutting tool designed to cut sheet
of all sorts using a steel wheel that doesn't spin but instead
oscillates at a fairly high frequency in an arc of about 20 degrees or
so. I saw it demonstrated on aluminum, steel and even stainless steel.
Really noisy, but a really clean cut, too. No chips. When the section
of the disc doing the work gets a bit dull, you loosen the screw and
rotate it a bit to a sharper section. I am trying to remember the
name, but can't. It was a big hit at our aircraft engineer's symposium
a couple of years ago. Not cheap, but well worth the cost if you're
doing much cutting.
Friction welding of aluminum aircraft skin was presented there,
too, though not demonstrated. Skins are butted together and a
high-speed carbide bit with a flat end and one raised tit are run over
the joint under pressure, the metal heats and fuses, and the alloy is
not affected so strength isn't hurt at all. I don't know how. You get
a flush, seamless joint with far less hassle than riveting. Also very
expensive. I think Airbus is using it on the A380, maybe.

Dan

Dan

In article ,
(Dan Thomas) wrote:

(Veeduber) wrote in message
...
One of the easiest ways to cut sheet 4130 is with a band saw. Use an
old metal cutting blade installed upside down (the teeth pointing up).
Run the saw at normal speed and feed in the material. Keep the
pressure up and it will go (melt) through like you are cutting butter.
Don't pause though, it is not so easy to get started again. Some have
also used the back side of the blade for this purpose with success.

O-ring Seals

---------------------------------------------------

Dear O-ring (and the Group),

I believe you'll find there's a bit more to it than that :-)

First off, the 'normal speed' you're referring to is for a woodworking
bandsaw.
The down-side is that most woodworking bandsaws are fitted with a rubber
'tire' on their driver- & idler-wheels. Friction cutting steel (which is
what
you're doing) will destroy the tire on the driver-wheel in short order.
Bandsaw tires are moderately expensive and can be hellishly difficult to
replace on some saws.

Metal-cutting bandsaws do not use tires. The wheels are sizes so that the
teeth overhang the edge of the wheel, not only for cooling but for clearing
the
swarf.

You can set-up a metal cutting bandsaw for friction cutting if you have the
proper ratio pulleys (ie, increase the blade speed).

The popularity of this method hinged largely on the builder's ability to
splice
their own blades because the original idea was to use common steel
strapping.
Operated at high speed -- and cutting relatively thin stock -- the stuff
does
in fact cut like butter, with a very attractive displace of sparks, too :-)
But the strapping was rapidly consumed and unless you were a dab hand at
splicing, ideally with a Do-All type butt-welder, there was no long-term
advantage over regular cutting.

All of this came about due to the difficulty of cutting relatively hard
steel
in thinner gauges, which loves to strip the teeth off anything. .035 4130,
you
can do pretty well using a regular bi-metallic 32T blade by simply rigging
the
work to feed 'downhill' so that two teeth are in contact with the work.


I used to cut 4130 using the bandsaw method, with a 1/2" bimetal
blade installed the right way, and just letting the teeth round off
the first time I used it. It would cut rather nicely, and didn't hurt
the rubber tire. Keeping the cut straight was the biggest hassle.
There's a German-made friction-cutting tool designed to cut sheet
of all sorts using a steel wheel that doesn't spin but instead
oscillates at a fairly high frequency in an arc of about 20 degrees or
so. I saw it demonstrated on aluminum, steel and even stainless steel.
Really noisy, but a really clean cut, too. No chips. When the section
of the disc doing the work gets a bit dull, you loosen the screw and
rotate it a bit to a sharper section. I am trying to remember the
name, but can't. It was a big hit at our aircraft engineer's symposium
a couple of years ago. Not cheap, but well worth the cost if you're
doing much cutting.
Friction welding of aluminum aircraft skin was presented there,
too, though not demonstrated. Skins are butted together and a
high-speed carbide bit with a flat end and one raised tit are run over
the joint under pressure, the metal heats and fuses, and the alloy is
not affected so strength isn't hurt at all. I don't know how. You get
a flush, seamless joint with far less hassle than riveting. Also very
expensive. I think Airbus is using it on the A380, maybe.

Dan

Dan

I would think that the seam would lose a lot of its basic heat treat
strength, due to the melting/recrystallization.

Orval Fairbairn wrote:
In article ,
(Dan Thomas) wrote:


(Veeduber) wrote in message
...

One of the easiest ways to cut sheet 4130 is with a band saw. Use an
old metal cutting blade installed upside down (the teeth pointing up).
Run the saw at normal speed and feed in the material. Keep the
pressure up and it will go (melt) through like you are cutting butter.
Don't pause though, it is not so easy to get started again. Some have
also used the back side of the blade for this purpose with success.

O-ring Seals


---------------------------------------------------

Dear O-ring (and the Group),

I believe you'll find there's a bit more to it than that :-)

First off, the 'normal speed' you're referring to is for a woodworking
bandsaw.
The down-side is that most woodworking bandsaws are fitted with a rubber
'tire' on their driver- & idler-wheels. Friction cutting steel (which is
what
you're doing) will destroy the tire on the driver-wheel in short order.
Bandsaw tires are moderately expensive and can be hellishly difficult to
replace on some saws.

Metal-cutting bandsaws do not use tires. The wheels are sizes so that the
teeth overhang the edge of the wheel, not only for cooling but for clearing
the
swarf.

You can set-up a metal cutting bandsaw for friction cutting if you have the
proper ratio pulleys (ie, increase the blade speed).

The popularity of this method hinged largely on the builder's ability to
splice
their own blades because the original idea was to use common steel
strapping.
Operated at high speed -- and cutting relatively thin stock -- the stuff
does
in fact cut like butter, with a very attractive displace of sparks, too :-)
But the strapping was rapidly consumed and unless you were a dab hand at
splicing, ideally with a Do-All type butt-welder, there was no long-term
advantage over regular cutting.

All of this came about due to the difficulty of cutting relatively hard
steel
in thinner gauges, which loves to strip the teeth off anything. .035 4130,
you
can do pretty well using a regular bi-metallic 32T blade by simply rigging
the
work to feed 'downhill' so that two teeth are in contact with the work.


I used to cut 4130 using the bandsaw method, with a 1/2" bimetal
blade installed the right way, and just letting the teeth round off
the first time I used it. It would cut rather nicely, and didn't hurt
the rubber tire. Keeping the cut straight was the biggest hassle.
There's a German-made friction-cutting tool designed to cut sheet
of all sorts using a steel wheel that doesn't spin but instead
oscillates at a fairly high frequency in an arc of about 20 degrees or
so. I saw it demonstrated on aluminum, steel and even stainless steel.
Really noisy, but a really clean cut, too. No chips. When the section
of the disc doing the work gets a bit dull, you loosen the screw and
rotate it a bit to a sharper section. I am trying to remember the
name, but can't. It was a big hit at our aircraft engineer's symposium
a couple of years ago. Not cheap, but well worth the cost if you're
doing much cutting.
Friction welding of aluminum aircraft skin was presented there,
too, though not demonstrated. Skins are butted together and a
high-speed carbide bit with a flat end and one raised tit are run over
the joint under pressure, the metal heats and fuses, and the alloy is
not affected so strength isn't hurt at all. I don't know how. You get
a flush, seamless joint with far less hassle than riveting. Also very
expensive. I think Airbus is using it on the A380, maybe.

Dan

Dan


I would think that the seam would lose a lot of its basic heat treat
strength, due to the melting/recrystallization.

A PDF on stir/friction welding from NASA.gov
http://makeashorterlink.com/?E472217A6


ww

"Aardvark" wrote in message ...
Orval Fairbairn wrote:
In article ,
(Dan Thomas) wrote:


snip
I used to cut 4130 using the bandsaw method, with a 1/2" bimetal
blade installed the right way, and just letting the teeth round off
the first time I used it. It would cut rather nicely, and didn't hurt
the rubber tire. Keeping the cut straight was the biggest hassle.
There's a German-made friction-cutting tool designed to cut sheet
of all sorts using a steel wheel that doesn't spin but instead
oscillates at a fairly high frequency in an arc of about 20 degrees or
so. I saw it demonstrated on aluminum, steel and even stainless steel.
Really noisy, but a really clean cut, too. No chips. When the section
of the disc doing the work gets a bit dull, you loosen the screw and
rotate it a bit to a sharper section. I am trying to remember the
name, but can't. It was a big hit at our aircraft engineer's symposium
a couple of years ago. Not cheap, but well worth the cost if you're
doing much cutting.
Friction welding of aluminum aircraft skin was presented there,
too, though not demonstrated. Skins are butted together and a
high-speed carbide bit with a flat end and one raised tit are run over
the joint under pressure, the metal heats and fuses, and the alloy is
not affected so strength isn't hurt at all. I don't know how. You get
a flush, seamless joint with far less hassle than riveting. Also very
expensive. I think Airbus is using it on the A380, maybe.

Dan

Dan


I would think that the seam would lose a lot of its basic heat treat
strength, due to the melting/recrystallization.

A PDF on stir/friction welding from NASA.gov
http://makeashorterlink.com/?E472217A6


ww


The Eclipse 500 is using a patented stir weld process...

--
Dan D.

Aardvark wrote in message .. .
Orval Fairbairn wrote:


I would think that the seam would lose a lot of its basic heat treat
strength, due to the melting/recrystallization.

A PDF on stir/friction welding from NASA.gov
http://makeashorterlink.com/?E472217A6


ww


That's the process. The metal, as they say, does not actually melt,
just plasticizes, and doesn't lose its strength.


Dan

It appears that my previous thank you note didn't get through. Maybe
it's a appropriate, 'cause now I get to thank everyone on Thanksgiving.
The generosity of members of this list is boundless. I actually had
several people volunteer to cut the sheet for me. I declined those
offers because of the shipping cost and difficulty of communication (and
I really do want to keep the 'I built that' element as much as possible).

I have an inlaw that has access to a portable plasma torch. I'm going
to get the sheet laid out and get up with him. I had actually forgotten
all about this particular resource until someone here mentioned it.
However, I'm still of the mind to hold back at least one piece so that I
can give that friction cutting method a try. Just 'cause I LIKE to see
sparks flying.

Beyond that, I've had dozens of occasions to recieve excellent
information from this newsgroup, both as direct responses to questions
I've posed and in responses to others...even from old curmudgeons(sp?)
like Barnyard Bob. Regardless of the amount of bickering and
namecalling, I firmly believe that everyone here has the goal of
building/help build the safest possible airplane at the least expense of
time, effort, and dollars. When I come flying into Sun'n'Fun or Oskosh
in a few years, you can all rest assured that you had a hand in getting
me there.

Thank you.

(PS - If I crash and burn on test flight, then it's all on my head.)

--
http://www.ernest.isa-geek.org/
"Ignorance is mankinds normal state,
alleviated by information and experience."
Veeduber