Subject: Coolant when sawing?

From: [email-masked] (Bob Neidorff)
Date: Mon, 23 Jan 1995 17:03:49 GMT

Well, I was hacksawing through a 3" x 1" mild steel bar.
My Nautilus coach would have been pleased.  :-)  

It took me 3/4 hour for the first piece.  :-(  Part of my
problem was using too fine of a blade.  I was using an 18 
TPI cheapie edge-hardened blade.  It seemed to stay sharp, 
so perhaps it was hard enough for the job.

I decided to try a squirt of Tap Magic.  What the heck.
Well, it seemed to reduce friction, and the stuff actually
smoked slightly when I cut, so something was getting hot in
there.  But the fluid on the contact point didn't last long,
and it caused the chips to stay in the teeth as a slurry.

Was I helping or hurting with this fluid?

Is there a better fluid for the job?

What do you use when hacksawing?

-- 
Bob Neidorff; Unitrode I. C. Corp.  |  Internet: [email-masked]
7 Continental Blvd.                 |  Voice   : (US) 603-429-8541
Merrimack, NH  03054-0399 USA       |  FAX     : (US) 603-424-3460

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From: [email-masked] (Mike Rehmus)
Date: 24 Jan 1995 05:30:51 GMT

>What do you use when hacksawing?

You have the correct idea, Bob.

The correct stroke speed is one stroke per second or slightly slower 
and lift on the back stroke.  Much faster and you will exceed the 
surface speed limit of the blade and lose the temper.

I use CoolTool II as it is thicker and stays in the cut.  The speed 
difference is about 2X faster if I use a lube over no lube.  A 
sulfer-based cutting oil (pipe threading lube) would also work 
but is messier.

Try one of the Starrett yellow blades at the proper pitch.  They last a 
long time and repay their slightly higher cost.

Mike

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From: [email-masked] (Russ Kepler)
Date: Tue, 24 Jan 1995 14:42:25 GMT

>What do you use when hacksawing?

When hacksawing CRS I usually use a coarse blade such as a 14
tooth/inch and Rigid thread cutting oil.  This is about as close to
the original "sulphurated oil" that you see in old references that you
can find anymore.  It sure helps the cutting, and the blades last a
lot longer (I'm using Starrett grey carbon blades in a high-tension
frame).

Sure bothers my machinist friends to come over and find that I cut all
that material by hand.  Most of them have been in shops with power
hacksaws and bandsaws too long to remember that there's a way to do it
with a vise and a handsaw.

-- 
Russ Kepler posting from home  [email-masked]

                      Please don't feed the Engineers