Welding 4130...

[Blueskies]

I am a rookie at this welding stuff, and plan to get plenty of practice before building real airplane parts. That said,
what do you all think about heat treating after welding? I will be gas welding. Do I really need 4130 rod, or can I use
another high carbon steel rod? How about 'S2' rod (only if not heat treating?)?

I have seen all sorts of discussion about this, but none of it is really clear. I know some of you folks are indeed
experts so I am seeking your advise.

Thanks All!

Dan D.
Kalamazoo, MI

[J.Kahn]

Blueskies wrote:
> I am a rookie at this welding stuff, and plan to get plenty of practice before building real airplane parts. That said,
> what do you all think about heat treating after welding? I will be gas welding. Do I really need 4130 rod, or can I use
> another high carbon steel rod? How about 'S2' rod (only if not heat treating?)?
>
> I have seen all sorts of discussion about this, but none of it is really clear. I know some of you folks are indeed
> experts so I am seeking your advise.
>
> Thanks All!
>
> Dan D.
> Kalamazoo, MI
>
>

Do not use 4130 rod, which would require oven heat treatment of the
welds. RG45 mild steel rod is best for gas welding. Also don't use ER
rod, which is also mild steel but which is formulated for arc and works
poorly with gas.

Mild steel rod provides perfectly adequate joints because the weld
fillet is several times thicker than the parent metal, while at the same
time being softer material it provides better fatigue resistance.

When doing finish welding of clusters, as the last weld of a cluster is
complete and while the cluster area is still hot, go back over the
cluster to bring the entire cluster up to dull red (not orange) then let
it air cool with no drafts. This brings the zone reasonably close to
the original normalized state of the parent metal and is all that is
necessary.

The secret to not burning through on thin tube at the start is to get
the parent metal just under the melting point and drop a molten bead of
rod on the joint, then heat the bead until the adjacent metal melts and
the bead blends into the parent metal. Then start adding more rod and
moving the torch.

The rod plays a role in heat control. When an edge starts to burn away
back off just slightly and put the rod in the way of the flame which
limits the heat to the burnout and deposits rod there to fill it in at
the same time, then keep going. This is the way to deal with burnaways
without getting all flustered and stopping.

Be generous with rod feed to the puddle to keep it "full" as you advance
to avoid undercut edges. If you get the puddle nice and full looking
and feathered into the parent material all round the edge, then just
move the torch along while keeping the puddle full with rod, you will
get a beautiful textbook bead that looks almost like a TIG bead with
full penetration.

Gas is great because it is very forgiving of imperfect technique and you
can go back over mistakes if necessary.


John

[Ernest Christley]

J.Kahn wrote:
> Blueskies wrote:
>> I am a rookie at this welding stuff, and plan to get plenty of
>> practice before building real airplane parts. That said, what do you
>> all think about heat treating after welding? I will be gas welding. Do
>> I really need 4130 rod, or can I use another high carbon steel rod?
>> How about 'S2' rod (only if not heat treating?)?
>>
>> I have seen all sorts of discussion about this, but none of it is
>> really clear. I know some of you folks are indeed experts so I am
>> seeking your advise.
>>
>> Thanks All!
>>
>> Dan D.
>> Kalamazoo, MI
>>
>
> Do not use 4130 rod, which would require oven heat treatment of the
> welds. RG45 mild steel rod is best for gas welding. Also don't use ER
> rod, which is also mild steel but which is formulated for arc and works
> poorly with gas.
>
> Mild steel rod provides perfectly adequate joints because the weld
> fillet is several times thicker than the parent metal, while at the same
> time being softer material it provides better fatigue resistance.
>
> When doing finish welding of clusters, as the last weld of a cluster is
> complete and while the cluster area is still hot, go back over the
> cluster to bring the entire cluster up to dull red (not orange) then let
> it air cool with no drafts. This brings the zone reasonably close to
> the original normalized state of the parent metal and is all that is
> necessary.
>
> The secret to not burning through on thin tube at the start is to get
> the parent metal just under the melting point and drop a molten bead of
> rod on the joint, then heat the bead until the adjacent metal melts and
> the bead blends into the parent metal. Then start adding more rod and
> moving the torch.
>
> The rod plays a role in heat control. When an edge starts to burn away
> back off just slightly and put the rod in the way of the flame which
> limits the heat to the burnout and deposits rod there to fill it in at
> the same time, then keep going. This is the way to deal with burnaways
> without getting all flustered and stopping.
>
> Be generous with rod feed to the puddle to keep it "full" as you advance
> to avoid undercut edges. If you get the puddle nice and full looking
> and feathered into the parent material all round the edge, then just
> move the torch along while keeping the puddle full with rod, you will
> get a beautiful textbook bead that looks almost like a TIG bead with
> full penetration.
>
> Gas is great because it is very forgiving of imperfect technique and you
> can go back over mistakes if necessary.
>
>
> John

Everything he said, with one addition. Practice on strips of thin sheet
stood on edge. You should be able to move down the edge, making a
rounded off fat bead that sort of sits as a bubble on tops. You should
pratice moving the torch in and out, getting the metal to melt but not
flow, and holding it there. Once you can do that, the thin walled tube
will be much easier.

[Blueskies]

"Ernest Christley" > wrote in message ...
: J.Kahn wrote:
: > Blueskies wrote:
: >> I am a rookie at this welding stuff, and plan to get plenty of
: >> practice before building real airplane parts. That said, what do you
: >> all think about heat treating after welding? I will be gas welding. Do
: >> I really need 4130 rod, or can I use another high carbon steel rod?
: >> How about 'S2' rod (only if not heat treating?)?
: >>
: >> I have seen all sorts of discussion about this, but none of it is
: >> really clear. I know some of you folks are indeed experts so I am
: >> seeking your advise.
: >>
: >> Thanks All!
: >>
: >> Dan D.
: >> Kalamazoo, MI
: >>
: >
: > Do not use 4130 rod, which would require oven heat treatment of the
: > welds. RG45 mild steel rod is best for gas welding. Also don't use ER
: > rod, which is also mild steel but which is formulated for arc and works
: > poorly with gas.
: >
: > Mild steel rod provides perfectly adequate joints because the weld
: > fillet is several times thicker than the parent metal, while at the same
: > time being softer material it provides better fatigue resistance.
: >
: > When doing finish welding of clusters, as the last weld of a cluster is
: > complete and while the cluster area is still hot, go back over the
: > cluster to bring the entire cluster up to dull red (not orange) then let
: > it air cool with no drafts. This brings the zone reasonably close to
: > the original normalized state of the parent metal and is all that is
: > necessary.
: >
: > The secret to not burning through on thin tube at the start is to get
: > the parent metal just under the melting point and drop a molten bead of
: > rod on the joint, then heat the bead until the adjacent metal melts and
: > the bead blends into the parent metal. Then start adding more rod and
: > moving the torch.
: >
: > The rod plays a role in heat control. When an edge starts to burn away
: > back off just slightly and put the rod in the way of the flame which
: > limits the heat to the burnout and deposits rod there to fill it in at
: > the same time, then keep going. This is the way to deal with burnaways
: > without getting all flustered and stopping.
: >
: > Be generous with rod feed to the puddle to keep it "full" as you advance
: > to avoid undercut edges. If you get the puddle nice and full looking
: > and feathered into the parent material all round the edge, then just
: > move the torch along while keeping the puddle full with rod, you will
: > get a beautiful textbook bead that looks almost like a TIG bead with
: > full penetration.
: >
: > Gas is great because it is very forgiving of imperfect technique and you
: > can go back over mistakes if necessary.
: >
: >
: > John
:
: Everything he said, with one addition. Practice on strips of thin sheet
: stood on edge. You should be able to move down the edge, making a
: rounded off fat bead that sort of sits as a bubble on tops. You should
: pratice moving the torch in and out, getting the metal to melt but not
: flow, and holding it there. Once you can do that, the thin walled tube
: will be much easier.


Thanks all! I have been practicing melting metal this week. Pretty amazing 'art', this welding. My blobs are not very
pretty (downright ugly in fact), and just getting the torch right is part of the battle. Great fun!

I don't have a bunch of thin scrap to work on, but I do have some old 1/8" iron that I am playing with, and then going
back to the 4130 scraps and blowing holes through it. I see Spruce has a grab bag of shorts that I will probably buy,
and I need about 1' of 3" wide 0.065" 4130, so I am planning to buy some strips from them also.

Side note, any hints on cutting the strip?

Thanks again!

Dan D. in Kalamazoo MI

[[email protected]]

On Feb 23, 5:20 pm, "Blueskies" > wrote:

> and I need about 1' of 3" wide 0.065" 4130, so I am planning to buy some strips from them also.
>
> Side note, any hints on cutting the strip?


Buy a metal-cutting abrasive disc (chop-saw disc) at the hardware
store in a size that'll fit your table saw. It'll zip through 4130
nicely. Lots of noise, lots of sparks, so wear hearing and eye
protection and make sure your work area is free of anything that might
burn or smolder.

Dan

[Blueskies]

> wrote in message oups.com...
: On Feb 23, 5:20 pm, "Blueskies" > wrote:
:
: > and I need about 1' of 3" wide 0.065" 4130, so I am planning to buy some strips from them also.
: >
: > Side note, any hints on cutting the strip?
:
:
: Buy a metal-cutting abrasive disc (chop-saw disc) at the hardware
: store in a size that'll fit your table saw. It'll zip through 4130
: nicely. Lots of noise, lots of sparks, so wear hearing and eye
: protection and make sure your work area is free of anything that might
: burn or smolder.
:
: Dan
:

Good idea, thanks!

lotsa sparks, smoldering, noise! Life is good!

Dan D.

[cavelamb himself]

Blueskies wrote:
> > wrote in message oups.com...
> : On Feb 23, 5:20 pm, "Blueskies" > wrote:
> :
> : > and I need about 1' of 3" wide 0.065" 4130, so I am planning to buy some strips from them also.
> : >
> : > Side note, any hints on cutting the strip?
> :
> :
> : Buy a metal-cutting abrasive disc (chop-saw disc) at the hardware
> : store in a size that'll fit your table saw. It'll zip through 4130
> : nicely. Lots of noise, lots of sparks, so wear hearing and eye
> : protection and make sure your work area is free of anything that might
> : burn or smolder.
> :
> : Dan
> :
>
> Good idea, thanks!
>
> lotsa sparks, smoldering, noise! Life is good!
>
> Dan D.
>
>

also - check Bud's "how to" corner...
Very helpful info about Zen and the Art of Welding.

http://www.airbum.com/articles/ArticleZenWelding.html

[Mike Young]

"Blueskies" > wrote in message
. ..
>
> > wrote in message
> oups.com...
> : On Feb 23, 5:20 pm, "Blueskies" > wrote:
> :
> : > and I need about 1' of 3" wide 0.065" 4130, so I am planning to buy
> some strips from them also.
> : >
> : > Side note, any hints on cutting the strip?
> :
> :
> : Buy a metal-cutting abrasive disc (chop-saw disc) at the hardware
> : store in a size that'll fit your table saw. It'll zip through 4130
> : nicely. Lots of noise, lots of sparks, so wear hearing and eye
> : protection and make sure your work area is free of anything that might
> : burn or smolder.
> :
> : Dan
> :
>
> Good idea, thanks!
>
> lotsa sparks, smoldering, noise! Life is good!

Great for entertaining the grandkids, but not so good if you're an arbor
bearing. The grit accelerates wear... yada yada. For stuff that size, buy a
small bench shear from Grizzly or Horrible Fright. It'll cost less than
overhauling your good power tools, not to mention being generally useful for
sheet metal work.

[Drew Dalgleish]

On Sat, 24 Feb 2007 02:40:35 -0600, "Mike Young"
> wrote:

>"Blueskies" > wrote in message
. ..
>>
>> > wrote in message
>> oups.com...
>> : On Feb 23, 5:20 pm, "Blueskies" > wrote:
>> :
>> : > and I need about 1' of 3" wide 0.065" 4130, so I am planning to buy
>> some strips from them also.
>> : >
>> : > Side note, any hints on cutting the strip?
>> :
>> :
>> : Buy a metal-cutting abrasive disc (chop-saw disc) at the hardware
>> : store in a size that'll fit your table saw. It'll zip through 4130
>> : nicely. Lots of noise, lots of sparks, so wear hearing and eye
>> : protection and make sure your work area is free of anything that might
>> : burn or smolder.
>> :
>> : Dan
>> :
>>
>> Good idea, thanks!
>>
>> lotsa sparks, smoldering, noise! Life is good!
>
>Great for entertaining the grandkids, but not so good if you're an arbor
>bearing. The grit accelerates wear... yada yada. For stuff that size, buy a
>small bench shear from Grizzly or Horrible Fright. It'll cost less than
>overhauling your good power tools, not to mention being generally useful for
>sheet metal work.
>
>
I haven't had a bearing fail on my saw yet but I think I could buy
quite a few before I got to the price of a shear.

[J.Kahn]

Blueskies wrote:
> "Ernest Christley" > wrote in message ...
> : J.Kahn wrote:
> : > Blueskies wrote:
> : >> I am a rookie at this welding stuff, and plan to get plenty of
> : >> practice before building real airplane parts. That said, what do you
> : >> all think about heat treating after welding? I will be gas welding. Do
> : >> I really need 4130 rod, or can I use another high carbon steel rod?
> : >> How about 'S2' rod (only if not heat treating?)?
> : >>
> : >> I have seen all sorts of discussion about this, but none of it is
> : >> really clear. I know some of you folks are indeed experts so I am
> : >> seeking your advise.
> : >>
> : >> Thanks All!
> : >>
> : >> Dan D.
> : >> Kalamazoo, MI
> : >>
> : >
> : > Do not use 4130 rod, which would require oven heat treatment of the
> : > welds. RG45 mild steel rod is best for gas welding. Also don't use ER
> : > rod, which is also mild steel but which is formulated for arc and works
> : > poorly with gas.
> : >
> : > Mild steel rod provides perfectly adequate joints because the weld
> : > fillet is several times thicker than the parent metal, while at the same
> : > time being softer material it provides better fatigue resistance.
> : >
> : > When doing finish welding of clusters, as the last weld of a cluster is
> : > complete and while the cluster area is still hot, go back over the
> : > cluster to bring the entire cluster up to dull red (not orange) then let
> : > it air cool with no drafts. This brings the zone reasonably close to
> : > the original normalized state of the parent metal and is all that is
> : > necessary.
> : >
> : > The secret to not burning through on thin tube at the start is to get
> : > the parent metal just under the melting point and drop a molten bead of
> : > rod on the joint, then heat the bead until the adjacent metal melts and
> : > the bead blends into the parent metal. Then start adding more rod and
> : > moving the torch.
> : >
> : > The rod plays a role in heat control. When an edge starts to burn away
> : > back off just slightly and put the rod in the way of the flame which
> : > limits the heat to the burnout and deposits rod there to fill it in at
> : > the same time, then keep going. This is the way to deal with burnaways
> : > without getting all flustered and stopping.
> : >
> : > Be generous with rod feed to the puddle to keep it "full" as you advance
> : > to avoid undercut edges. If you get the puddle nice and full looking
> : > and feathered into the parent material all round the edge, then just
> : > move the torch along while keeping the puddle full with rod, you will
> : > get a beautiful textbook bead that looks almost like a TIG bead with
> : > full penetration.
> : >
> : > Gas is great because it is very forgiving of imperfect technique and you
> : > can go back over mistakes if necessary.
> : >
> : >
> : > John
> :
> : Everything he said, with one addition. Practice on strips of thin sheet
> : stood on edge. You should be able to move down the edge, making a
> : rounded off fat bead that sort of sits as a bubble on tops. You should
> : pratice moving the torch in and out, getting the metal to melt but not
> : flow, and holding it there. Once you can do that, the thin walled tube
> : will be much easier.
>
>
> Thanks all! I have been practicing melting metal this week. Pretty amazing 'art', this welding. My blobs are not very
> pretty (downright ugly in fact), and just getting the torch right is part of the battle. Great fun!
>
> I don't have a bunch of thin scrap to work on, but I do have some old 1/8" iron that I am playing with, and then going
> back to the 4130 scraps and blowing holes through it. I see Spruce has a grab bag of shorts that I will probably buy,
> and I need about 1' of 3" wide 0.065" 4130, so I am planning to buy some strips from them also.
>
> Side note, any hints on cutting the strip?
>
> Thanks again!
>
> Dan D. in Kalamazoo MI
>
>
>
Dunno what torch you're using Dan, but I can highly recommend the Meco
Midget with a 0, 1, 2 and 3 tip, plus a 0 tip drilled to halfway between
0 and 1 (# 74 wire drill). The 0 for .028, the 0.5 for .035, the 1 for
..035 in dense areas and sometimes .049, and the 2 for .049, and the 3
and possibly a #4 for .065. The "Tinman", Kent White, sells the Meco
for a fantastic price and has a really good and quite comprehensive DVD
on building a tube fuselage done with Earl Luce the Buttercup Guy and
Joe Maj, an Oshkosh welding guru and a chemistry PhD.

The Midget is actually a jeweler's torch, but in the big end of the
range as jeweler's torches go and is perfect for thinwall tube since it
is feather light and you can hold it in your hand like a pen. When you
get the tip size and gas flow right for the job it doesn't pop. I
absolutely love mine.

The other torch I really like is the Henrob but it is really heavy and
a bit awkward in tight spaces. The Henrob does great flame cuts but
this is a no no on aircraft metal because the flame cut edge is heavily
oxidized.

If you are perceptive and learn what to look for you can acquire most of
the skill to do good welds by practicing on your own with the help of
reading materials and videos. When you are to the point in the future
where you think your welds are airworthy, cut up some cross section
samples and take them to a certified welder for some critique.

John

[[email protected]]

Check out: http://www.jumprunenterprises.com

[[email protected]]

To view clips from a 4130 Steel Tube Airframe Construction DVD, visit:

http://www.jumprunenterprises.com

[[email protected]]

On Feb 24, 1:40 am, "Mike Young" > wrote:
> "Blueskies" > wrote in message
>
> . ..
>
>
>
>
>
>
>
> > > wrote in message
> oups.com...
> > : On Feb 23, 5:20 pm, "Blueskies" > wrote:
> > :
> > : > and I need about 1' of 3" wide 0.065" 4130, so I am planning to buy
> > some strips from them also.
> > : >
> > : > Side note, any hints on cutting the strip?
> > :
> > :
> > : Buy a metal-cutting abrasive disc (chop-saw disc) at the hardware
> > : store in a size that'll fit your table saw. It'll zip through 4130
> > : nicely. Lots of noise, lots of sparks, so wear hearing and eye
> > : protection and make sure your work area is free of anything that might
> > : burn or smolder.
> > :
> > : Dan
> > :
>
> > Good idea, thanks!
>
> > lotsa sparks, smoldering, noise! Life is good!
>
> Great for entertaining the grandkids, but not so good if you're an arbor
> bearing. The grit accelerates wear... yada yada. For stuff that size, buy a
> small bench shear from Grizzly or Horrible Fright. It'll cost less than
> overhauling your good power tools, not to mention being generally useful for
> sheet metal work.- Hide quoted text -
>
> - Show quoted text -

Been cutting steel on a couple of tablesaws for a long time
now. No bearing hassles. If the bearings were really old and the seals
were gone, it sure would be a problem.


Dan

[Maxwell]

"Blueskies" > wrote in message news:VwLDh.1061
> I don't have a bunch of thin scrap to work on, but I do have some old 1/8"
> iron that I am playing with, and then going
> back to the 4130 scraps and blowing holes through it. I see Spruce has a
> grab bag of shorts that I will probably buy,
> and I need about 1' of 3" wide 0.065" 4130, so I am planning to buy some
> strips from them also.
>
> Side note, any hints on cutting the strip?
>

You might be able to cut .065" on a wood cutting band saw, on high speed,
the faster the better. Use an old fine tooth blade. Leaves a nasty burr, but
cuts very fast.

I used to cut sheet steel this way quite often. But I don't remember how
thick. It might be limited to 030 or 040, but I think I have done some 065
with good results.

Kind of like cutting barn metal with a skill saw, and the blade mounted
backwards.

[Morgans[_2_]]

<Dan_> wrote
> Been cutting steel on a couple of tablesaws for a long time
> now. No bearing hassles. If the bearings were really old and the seals
> were gone, it sure would be a problem.

I third your no problems.

I have an Old Milwaukee circular saw that I have been using since 1982, and
a good part of that was 5 days a week professional carpentry. It has also
cut way too many feet of steel to count, up to 3/8" thick.

It has never had the bearings touched, or even regreased.

I'm not sure how much of this is a testament for the saw's manufacturer, or
that cutting steel will not hurt bearings.
--
Jim in NC

[Maxwell]

"Morgans" > wrote in message
...
>
> <Dan_> wrote
>> Been cutting steel on a couple of tablesaws for a long time
>> now. No bearing hassles. If the bearings were really old and the seals
>> were gone, it sure would be a problem.
>
> I third your no problems.
>
> I have an Old Milwaukee circular saw that I have been using since 1982,
> and a good part of that was 5 days a week professional carpentry. It has
> also cut way too many feet of steel to count, up to 3/8" thick.
>
> It has never had the bearings touched, or even regreased.
>
> I'm not sure how much of this is a testament for the saw's manufacturer,
> or that cutting steel will not hurt bearings.
> --
> Jim in NC
>

I have had a bearing problems with my Skil Saw. Not the motor, but the guard
bearing is very rough from cutting metal siding.

While *most* sealed bearings found on motors or jackshafts *shouldn't* have
a problem. A number of guards and guides found on woodworking equipent were
not designed with metal grindings in mind, and they can indeed cause a
problem.

Also, most quality friction saws designed for steel include TEFC, totally
enclosed fan cooled motors. While circular saws and most table saws do not.
And unlike wood dust, the build up of metallic duct inside these motors can
easily cause dangerous and catistrophic failures. Read *fireworks* and
shocking experiences. Especially in the quality metal framed tools like the
older Skil and Milwaukee brands. So your mileage may certainly vary.

The only problems I have personally experienced with Old Milwaukee brand
products were different levels of morning sickness.

[Morgans[_2_]]

"Maxwell" > wrote

> I have had a bearing problems with my Skil Saw. Not the motor, but the
> guard bearing is very rough from cutting metal siding.

That is a definite problem, but easily cured by taking apart the guard, and
cleaning and regreasing the sliding surfaces. That is all they are, is two
pieces of metal sliding on each other, with a brass shim between some of
them.

I have had far more problems with the guard gunking up cutting concrete and
other masonry, than cutting steel. Again, about a half hour, clean the
guard, and back in business.

>
> The only problems I have personally experienced with Old Milwaukee brand
> products were different levels of morning sickness.

<chuckle> That HAD to be a Freudian slip, or something. I too, have been
harmed far more by OLD Milwaukee, than by my Milwaukee circular saw.

No doubt, those blades make a mess. Cleaning is a necessary part of the
deal.

Nowadays, diamond blades are cheap enough to justify using them, over the
sacrificing blades. They are much cleaner.
--
Jim in NC

[J.Kahn]

Maxwell wrote:
> "Blueskies" > wrote in message news:VwLDh.1061
>> I don't have a bunch of thin scrap to work on, but I do have some old 1/8"
>> iron that I am playing with, and then going
>> back to the 4130 scraps and blowing holes through it. I see Spruce has a
>> grab bag of shorts that I will probably buy,
>> and I need about 1' of 3" wide 0.065" 4130, so I am planning to buy some
>> strips from them also.
>>
>> Side note, any hints on cutting the strip?
>>
>
> You might be able to cut .065" on a wood cutting band saw, on high speed,
> the faster the better. Use an old fine tooth blade. Leaves a nasty burr, but
> cuts very fast.
>
> I used to cut sheet steel this way quite often. But I don't remember how
> thick. It might be limited to 030 or 040, but I think I have done some 065
> with good results.
>
> Kind of like cutting barn metal with a skill saw, and the blade mounted
> backwards.
>
>
>
Are you talking about friction cutting?

[Maxwell]

"J.Kahn" > wrote in message
...
> Maxwell wrote:
>> "Blueskies" > wrote in message
>> news:VwLDh.1061
>>> I don't have a bunch of thin scrap to work on, but I do have some old
>>> 1/8" iron that I am playing with, and then going
>>> back to the 4130 scraps and blowing holes through it. I see Spruce has a
>>> grab bag of shorts that I will probably buy,
>>> and I need about 1' of 3" wide 0.065" 4130, so I am planning to buy some
>>> strips from them also.
>>>
>>> Side note, any hints on cutting the strip?
>>>
>>
>> You might be able to cut .065" on a wood cutting band saw, on high speed,
>> the faster the better. Use an old fine tooth blade. Leaves a nasty burr,
>> but cuts very fast.
>>
>> I used to cut sheet steel this way quite often. But I don't remember how
>> thick. It might be limited to 030 or 040, but I think I have done some
>> 065 with good results.
>>
>> Kind of like cutting barn metal with a skill saw, and the blade mounted
>> backwards.
>>
>>
>>
> Are you talking about friction cutting?

I guess you would have to call it that. It was told to me years ago from a
old sheet metal journeyman. It did forget to mention though, it makes a LOT
of noise. I have done a lot of 22 ga. steel. But I think I did some 065
stainless too, but it's been too long to recall for sure. If you have a
vertical band saw that will run 600 fpm or up, grab an old 8 pitch blade,
max the speed out, and give it a try. It takes a bit of extra feed pressure,
so be careful where you place your fingers. The material jumps a bit at the
end of each cut, just like anytime you use a lot of feed pressure.
Surprisingly the blade seems to last forever.

[J.Kahn]

Maxwell wrote:
> "J.Kahn" > wrote in message
> ...
>> Maxwell wrote:
>>> "Blueskies" > wrote in message
>>> news:VwLDh.1061
>>>> I don't have a bunch of thin scrap to work on, but I do have some old
>>>> 1/8" iron that I am playing with, and then going
>>>> back to the 4130 scraps and blowing holes through it. I see Spruce has a
>>>> grab bag of shorts that I will probably buy,
>>>> and I need about 1' of 3" wide 0.065" 4130, so I am planning to buy some
>>>> strips from them also.
>>>>
>>>> Side note, any hints on cutting the strip?
>>>>
>>> You might be able to cut .065" on a wood cutting band saw, on high speed,
>>> the faster the better. Use an old fine tooth blade. Leaves a nasty burr,
>>> but cuts very fast.
>>>
>>> I used to cut sheet steel this way quite often. But I don't remember how
>>> thick. It might be limited to 030 or 040, but I think I have done some
>>> 065 with good results.
>>>
>>> Kind of like cutting barn metal with a skill saw, and the blade mounted
>>> backwards.
>>>
>>>
>>>
>> Are you talking about friction cutting?
>
> I guess you would have to call it that. It was told to me years ago from a
> old sheet metal journeyman. It did forget to mention though, it makes a LOT
> of noise. I have done a lot of 22 ga. steel. But I think I did some 065
> stainless too, but it's been too long to recall for sure. If you have a
> vertical band saw that will run 600 fpm or up, grab an old 8 pitch blade,
> max the speed out, and give it a try. It takes a bit of extra feed pressure,
> so be careful where you place your fingers. The material jumps a bit at the
> end of each cut, just like anytime you use a lot of feed pressure.
> Surprisingly the blade seems to last forever.
>
>
>
What I've read about is taking an old blade and filing off the teeth to
make it smooth and friction cutting that way. I was cutting a little
piece of mild steel on a hobby band saw with a small 1/2 inch metal
cutting blade, and it seemed like the teeth were doing nothing but when
I pushed hard enough suddenly it would go quickly until the blade would
jam and bog it down. I guess it was friction cutting but it didn't get
red or anything.

[Maxwell]

----- Original Message -----
From: "J.Kahn" >
>>
> What I've read about is taking an old blade and filing off the teeth to
> make it smooth and friction cutting that way. I was cutting a little
> piece of mild steel on a hobby band saw with a small 1/2 inch metal
> cutting blade, and it seemed like the teeth were doing nothing but when I
> pushed hard enough suddenly it would go quickly until the blade would jam
> and bog it down. I guess it was friction cutting but it didn't get red or
> anything.

That's it, but you really don't have to file the teeth. I just mount an old
blade and go for it. The teeth wear pretty quickly.

In your case it sounds like you might not have had quite enough horsepower.
You do have to push fairly hard, and the material does feed quite quickly,
but you shouldn't bog down. I was using a 12" saw, 3/4 hp motor. I was also
using a lot more speed than I guessed earlier. I think my wood saw is closer
to 2800 feet per minute.