Hi. I saw a message posted to this group by someone saying that he
can cut 1 square inch of soft steel cross section in 60 seconds. That
sounded pretty fast to me, and I decided to give it a try. I was able
to cut about half a square inch of steel bar in about 30 minutes.
This is with a regular Craftsman hacksaw with a good blade. I am
using a large vise which holds the work steadily. I used a small
amount of gear oil in the kerf. The saw is cutting (I can feel it
bite on the cutting stroke), and filings are coming out. Actually, a
1/2 inch square cut is quite a bit of filings. But this is
approximately 1/60th the rate that the newsgroup post alluded to. I
thought that I should be at least within a factor of 10. The steel
that I am using is part of a bracket, and it cuts easily with a file
(no skate).

I know that an expert computer programmer can program 60 times faster
than a beginner, and get paid 10 times as much, but computer software
is a strange animal. I would think that I should be able to get
within a factor of 10. The blade wasn't buckling, so I think that a
high-tension hacksaw would not give all that much of a boost. It may
improve cutting speed by a factor of 3.

So, how does one cut a square inch of steel in 60 seconds? Inches do
matter!

Thanks,
Eric

"Eric Chang" wrote in message
om...
Hi. I saw a message posted to this group by someone saying that he
can cut 1 square inch of soft steel cross section in 60 seconds. That
sounded pretty fast to me, and I decided to give it a try. I was able
to cut about half a square inch of steel bar in about 30 minutes.
This is with a regular Craftsman hacksaw with a good blade. I am
using a large vise which holds the work steadily. I used a small
amount of gear oil in the kerf. The saw is cutting (I can feel it
bite on the cutting stroke), and filings are coming out. Actually, a
1/2 inch square cut is quite a bit of filings. But this is
approximately 1/60th the rate that the newsgroup post alluded to. I
thought that I should be at least within a factor of 10. The steel
that I am using is part of a bracket, and it cuts easily with a file
(no skate).

I know that an expert computer programmer can program 60 times faster
than a beginner, and get paid 10 times as much, but computer software
is a strange animal. I would think that I should be able to get
within a factor of 10. The blade wasn't buckling, so I think that a
high-tension hacksaw would not give all that much of a boost. It may
improve cutting speed by a factor of 3.

So, how does one cut a square inch of steel in 60 seconds? Inches do
matter!

Thanks,
Eric

Your blade probably has too many teeth to get a bite into the steel with
your available down pressure. It isn't a linear affect. 10 to 14 tpi is a
better bet for 1/2".

The rule about not pushing down, just letting the blade do the work may
apply to wood but not steel.

At risk of the thread going OT, the Craftsman aspect may part of the problem
:-)

Bob

In article , Eric Chang says...

using a large vise which holds the work steadily. I used a small
amount of gear oil in the kerf.

Gear oil is an extreme pressure lubricant. Don't use
it for cutting. Use a cutting fluid like lard oil.

Use the best HSS blade you can find, with coarse
enough teeth.

Jim

==================================================
please reply to:
JRR(zero) at yktvmv (dot) vnet (dot) ibm (dot) com
==================================================

Definetly doing *something* wrong, as last week I cut through an annealed
torsion bar in a few minutes... that's 1-1/8" or so round!
Dulled my blade though...can't cut crap with it anymore... must finish power
hacksaw project....

Tim

--
"I have misplaced my pants." - Homer Simpson | Electronics,
- - - - - - - - - - - - - - - - - - - - - - --+ Metalcasting
and Games: http://webpages.charter.net/dawill/tmoranwms

"Eric Chang" wrote in message
om...
Hi. I saw a message posted to this group by someone saying that he
can cut 1 square inch of soft steel cross section in 60 seconds. That
sounded pretty fast to me, and I decided to give it a try. I was able
to cut about half a square inch of steel bar in about 30 minutes.
This is with a regular Craftsman hacksaw with a good blade. I am
using a large vise which holds the work steadily. I used a small
amount of gear oil in the kerf. The saw is cutting (I can feel it
bite on the cutting stroke), and filings are coming out. Actually, a
1/2 inch square cut is quite a bit of filings. But this is
approximately 1/60th the rate that the newsgroup post alluded to. I
thought that I should be at least within a factor of 10. The steel
that I am using is part of a bracket, and it cuts easily with a file
(no skate).

I know that an expert computer programmer can program 60 times faster
than a beginner, and get paid 10 times as much, but computer software
is a strange animal. I would think that I should be able to get
within a factor of 10. The blade wasn't buckling, so I think that a
high-tension hacksaw would not give all that much of a boost. It may
improve cutting speed by a factor of 3.

So, how does one cut a square inch of steel in 60 seconds? Inches do
matter!

Thanks,
Eric

I wonder how many of us could actually cut a 1" square piece of steel in one
minute with a hand saw. I know if I tried, I would be winded, and probably
would run overtime.

Hell, it takes me a least 2-3 minutes to cut off a 1 inch diameter steel rod in
my lathe spinning at high speed with a new, sharp hacksaw blade. By the time
it's done, I'm breathing hard, cussing, sweating, etc.

Mike Eberlein

Leo Lichtman wrote:

I wonder how many of us could actually cut a 1" square piece of steel in one
minute with a hand saw. I know if I tried, I would be winded, and probably
would run overtime.

"Eric Chang" wrote in message
om...
Hi. I saw a message posted to this group by someone saying that he
can cut 1 square inch of soft steel cross section in 60 seconds. That
sounded pretty fast to me, and I decided to give it a try. I was able
to cut about half a square inch of steel bar in about 30 minutes.

Strike a bloody light!
I'd almost forgotten how painful a power hacksaw is.

6 to 10 *seconds* would be about right to get through a one inch square steel bar
using my Brobo cold cut-off saw - plus, the finish on the cut ends is "milled"
super-smooth.

Power hacksaws?
Weld a steel loop on them, and donate them to a local boat owner.

Jeff

One of the (many) things guaranteed to set me off is seeing a student
cutting stock in a lathe as you describe. I believe that it is
extremely dangerous and downright foolish.

Of course in your shop you may do as you wish but in mine it is
verboten!

Errol Groff
Instructor, Machine Tool Department
H.H. Ellis Tech
613 Upper Maple Street
Danielson, CT 06239

860 774 8511 x1811

http://pages.cthome.net/errol.groff/

http://newenglandmodelengineeringsociety.org/



On Fri, 05 Mar 2004 17:07:51 -0600, mikee wrote:

Hell, it takes me a least 2-3 minutes to cut off a 1 inch diameter steel rod in
my lathe spinning at high speed with a new, sharp hacksaw blade. By the time
it's done, I'm breathing hard, cussing, sweating, etc.

Mike Eberlein

Leo Lichtman wrote:

I wonder how many of us could actually cut a 1" square piece of steel in one
minute with a hand saw. I know if I tried, I would be winded, and probably
would run overtime.

"mikee" wrote in message
...
Hell, it takes me a least 2-3 minutes to cut off a 1 inch diameter steel
rod in
my lathe spinning at high speed with a new, sharp hacksaw blade. By the
time
it's done, I'm breathing hard, cussing, sweating, etc.

Mike Eberlein

As Errol suggests, this practice seems very dangerous. Further, it seems
very slow. Parting tools are made for this application and are very capable
when used correctly.

I understand that most HSM's are not *really* concerned with how every 15sec
period of their day is spent, but parting is so much easier....

As for the hacksaw, it's almost certainly the blade being the wrong tpi (and
if it's dulling, buy a better blade - Starrett makes nice bimetal blades).
At work we do a lot of bench work. I use a 14tpi blade for cutting anything
including or larger than 1/8". I'd say 60sec for 1in square is perhaps
pushing it, but 120sec is ample time. Yes, it's a lot of work, but that's
why we have electricity.

Regards,

Robin

On Sat, 6 Mar 2004 11:55:18 +1100, "A.Gent" wrote:
Strike a bloody light!
I'd almost forgotten how painful a power hacksaw is.

6 to 10 *seconds* would be about right to get through a one inch square steel bar
using my Brobo cold cut-off saw - plus, the finish on the cut ends is "milled"
super-smooth.

Power hacksaws?
Weld a steel loop on them, and donate them to a local boat owner.

So, how do you do internal cuts? Your cold saw can't get in there,
breaking and rewelding a bandsaw blade is a pain, but it is simple
to thread a power hacksaw blade through a starter hole. Works with
hand hacksaws too, if the frame is large enough.

BTW, my favorite hand hacksaw is a big sturdy bow frame (3 to 4 feet
long) with a length of bandsaw blade used as the hacksaw blade. Long
strokes, cuts quick, and you can really crank in some tension on the
blade to help it cut true.

Gary

"Gary Coffman" wrote in message
...
On Sat, 6 Mar 2004 11:55:18 +1100, "A.Gent" wrote:
Strike a bloody light!
I'd almost forgotten how painful a power hacksaw is.

6 to 10 *seconds* would be about right to get through a one inch square steel bar
using my Brobo cold cut-off saw - plus, the finish on the cut ends is "milled"
super-smooth.

Power hacksaws?
Weld a steel loop on them, and donate them to a local boat owner.

So, how do you do internal cuts? Your cold saw can't get in there,
breaking and rewelding a bandsaw blade is a pain, but it is simple
to thread a power hacksaw blade through a starter hole. Works with
hand hacksaws too, if the frame is large enough.

Yep. True. But:
In the past 25 years I could count the number of times I've needed to do that on one
hand. And then, I'd use a hand hacksaw.

But point taken.

Thing is, though, when I used to use a power hacksaw, I'd typically set it up and
then go and then go and do something else for a while. With the cold cutoff, I set
it up, cut, and its done.

The former is relaxing, but frustrating.
The latter is no less relaxing, and immensely satisfying.

Clearance can be a pain for some cuts too, I'll admit. And short pieces.

BTW, my favorite hand hacksaw is a big sturdy bow frame (3 to 4 feet
long) with a length of bandsaw blade used as the hacksaw blade. Long
strokes, cuts quick, and you can really crank in some tension on the
blade to help it cut true.

Gary

Wowsers. Same here, but for wood, not metal.
I really like my big old home-made wood bowsaw (with rope tensioner).

Jeff

"mikee" wrote in message ...
Hell, it takes me a least 2-3 minutes to cut off a 1 inch diameter steel rod in
my lathe spinning at high speed with a new, sharp hacksaw blade. By the time
it's done, I'm breathing hard, cussing, sweating, etc.

Mike Eberlein

"mikee" writes in message ...
at some future date...

Hi guys!
I'm typing this with one hand because the lathe ripped my arm off...

Just for grins after reading this thread I grabbed a 1 1/8" piece of square
steel, and hacksawed it through with a hand hacksaw, wimpy frame and a used
18 tpi 10" long blade. Took ~2.5 minutes. I then took the same stock and
put it in the old benchtop power hacksaw I have with a 14 tpi 12" blade.
The machine took ~6 minutes running at 90 strokes a minute. The machine
strokes about 5" per stroke, I stroked about 9" per stroke and about the
same speed, with a coupla short breaks . After the machine was done cutting
I did notice that I was puffing a lot less than when doing it by hand.
lg
no neat sig line
"Eric Chang" wrote in message
om...
Hi. I saw a message posted to this group by someone saying that he
can cut 1 square inch of soft steel cross section in 60 seconds. That
sounded pretty fast to me, and I decided to give it a try. I was able
to cut about half a square inch of steel bar in about 30 minutes.
This is with a regular Craftsman hacksaw with a good blade. I am
using a large vise which holds the work steadily. I used a small
amount of gear oil in the kerf. The saw is cutting (I can feel it
bite on the cutting stroke), and filings are coming out. Actually, a
1/2 inch square cut is quite a bit of filings. But this is
approximately 1/60th the rate that the newsgroup post alluded to. I
thought that I should be at least within a factor of 10. The steel
that I am using is part of a bracket, and it cuts easily with a file
(no skate).

I know that an expert computer programmer can program 60 times faster
than a beginner, and get paid 10 times as much, but computer software
is a strange animal. I would think that I should be able to get
within a factor of 10. The blade wasn't buckling, so I think that a
high-tension hacksaw would not give all that much of a boost. It may
improve cutting speed by a factor of 3.

So, how does one cut a square inch of steel in 60 seconds? Inches do
matter!

Thanks,
Eric

PR wrote:
"mikee" wrote in message ...
Hell, it takes me a least 2-3 minutes to cut off a 1 inch diameter steel rod in
my lathe spinning at high speed with a new, sharp hacksaw blade. By the time
it's done, I'm breathing hard, cussing, sweating, etc.

Mike Eberlein

"mikee" writes in message ...
at some future date...

Hi guys!
I'm typing this with one hand because the lathe ripped my arm off...

surely Mikee is jesting(?). what exactly is the method? unless you
are running the crossfeed you will be dulling teeth almost instantly.
maybe that is why he sweats? --Loren

"larry g" wrote in message ...
Just for grins after reading this thread I grabbed a 1 1/8" piece of square
steel, and hacksawed it through with a hand hacksaw, wimpy frame and a used
18 tpi 10" long blade. Took ~2.5 minutes. I then took the same stock and
....
Hi Larry. Thanks for the real life data. There have been a lot of good
suggestions. One of the problems is that I am using a 24 tpi blade. The
hacksaw is tightened very well, and the frame is reasonably sturdy. It
is cutting (there are a lot of metal filings), but just too slowly. I tried
cutting a 1/2 inch piece of rebar. It took 10 minutes. This is in line with
the 1 hour per square inch of material cut.

There was a suggestion to use a high quality coarse blade, like a Starret.
I'll give that a try. If I can do 1 square inch in 2 minutes, or even in
5 minutes, that will be great!

Thanks,
Eric

"Robin S." wrote in message ...
....
As for the hacksaw, it's almost certainly the blade being the wrong tpi (and
if it's dulling, buy a better blade - Starrett makes nice bimetal blades).
At work we do a lot of bench work. I use a 14tpi blade for cutting anything
including or larger than 1/8". I'd say 60sec for 1in square is perhaps
pushing it, but 120sec is ample time. Yes, it's a lot of work, but that's
why we have electricity.

Regards,

Robin

Hi Robin. This sounds like a great suggestion. It is a bit hard to find 14
tpi blades around here, but I will try ordering some online. I am not afraid
of some work; I need the exercise anyhow.

Thanks,
Eric

Subject: hacksaw cutting slowly
From: (Eric Chang)
Date: 10/03/04 16:51 GMT Standard Time
Message-id:

"larry g" wrote in message
...
Just for grins after reading this thread I grabbed a 1 1/8" piece of square
steel, and hacksawed it through with a hand hacksaw, wimpy frame and a used
18 tpi 10" long blade. Took ~2.5 minutes. I then took the same stock and
...
Hi Larry. Thanks for the real life data. There have been a lot of good
suggestions. One of the problems is that I am using a 24 tpi blade.

Not ideal but even so I'm surprised it cuts that slowly. 18 tpi is a good all
purpose blade.


The
hacksaw is tightened very well, and the frame is reasonably sturdy. It
is cutting (there are a lot of metal filings), but just too slowly. I tried
cutting a 1/2 inch piece of rebar. It took 10 minutes. This is in line with
the 1 hour per square inch of material cut.

Cutting the heads off a couple of 3/8" bolts the other day took maybe 15
seconds each with an 18 tpi blade. You could double that for a 1/2" bolt. A 24
tpi should be fine for steel although a bit slower than a coarser blade so I
have to conclude your blades are blunt or crappy quality.


Dave Baker - Puma Race Engines (www.pumaracing.co.uk)
I'm not at all sure why women like men. We're argumentative, childish,
unsociable and extremely unappealing naked. I'm quite grateful they do though.

Subject: hacksaw cutting slowly
From: (Eric Chang)
Date: 10/03/04 16:51 GMT Standard Time
Message-id:

"larry g" wrote in message
...
Just for grins after reading this thread I grabbed a 1 1/8" piece of square
steel, and hacksawed it through with a hand hacksaw, wimpy frame and a used
18 tpi 10" long blade. Took ~2.5 minutes. I then took the same stock and
...
Hi Larry. Thanks for the real life data. There have been a lot of good
suggestions. One of the problems is that I am using a 24 tpi blade. The
hacksaw is tightened very well, and the frame is reasonably sturdy. It
is cutting (there are a lot of metal filings), but just too slowly. I tried
cutting a 1/2 inch piece of rebar. It took 10 minutes. This is in line with
the 1 hour per square inch of material cut.

Also in the interests of science. Just been out to the workshop to find a bit
of scrap bar to test on. 5/8" round steel bar, not sure what grade but it had a
paint code on the end and was maybe better than mild steel. Brand new 18 tpi
blade. Two trials, 20.0 seconds and 18.8 seconds and that included maybe a
second getting my left hand off the stopwatch and onto the saw and another
second at the end when I stopped the watch.

That was going mental with the saw mind you and no attention to trying to cut
any sort of a neat or straight line so I shifted a bit more metal than if I'd
cut it perpendicular to the axis.

So call it 18 seconds which would make it (8/5) squared or 2.56 times as long
for a 1" round bar = 46 seconds. Calculate all that out into square inches and
near as dammit 1 minute per square inch. I'd add a bit to that though for
making a neater cut and also not giving oneself a heart attack by the end of
the day. 2 minutes would be comfy.

I would say that a quality 18 tpi blade will make your life a lot easier.


Dave Baker - Puma Race Engines (www.pumaracing.co.uk)
I'm not at all sure why women like men. We're argumentative, childish,
unsociable and extremely unappealing naked. I'm quite grateful they do though.

There was a suggestion to use a high quality coarse blade, like a Starret.
I'll give that a try. If I can do 1 square inch in 2 minutes, or even in
5 minutes, that will be great!


If you're using a Starret blade you might have trouble with the cut. A
Starrett blade, though, should be fine.

I'm not nitpicking here - there's a story involved.

Douglas R. Starrett was my father in law. He was quite a guy. Began working
for the company in the toolmaking program in 1941 and, except for the WW2
years, was there until he died in 2001.

He was up at the house one day, and I kidded him about the guys in the shop not
being able to spell the company's name correctly. I showed him a carbon steel
hacksaw blade marked "Starret". He was immediately all over me, wanting to
know where I had gotten it, what the package had said, and so on. He relaxed
only when I explained that it had been in my grandfather's tool chest and
probably dated from the 1950s or earlier. He said with evident relief that
there had been some counterfeit blades on the market then which they thought
had originated in Mexico. He said that the US on the blade was also a
giveaway, as the Starrett company always used the full "USA".

Then there was the time I saw a spray can of WD-40 on his kitchen counter.
Starrett makes a competitor to it, M-1, which is a bit heavier and has greases
and waxes in it that make it a lubricant and long-term rust preventative, but
it is used for many of the same purposes. When I asked him why the WD-40, he
replied that he had gotten it for his mother, who was in her 90s at the time.
I was confused, and asked him why he would buy it instead of M-1 and just what
the hell his mother would need it for anyway. He laughed and replied that the
DMSO in the WD-40 seemed to help with her arthritis. First time I ever heard
that one.

John Martin