Subject: Cutting metal on bandsaw meant for wood

From: Les Bartel <[email-masked]>
Date: Mon, 10 Feb 1997 07:52:17 -0600

I've been toying with the idea of putting a larger pully on the shaft
driven by the motor to slow my saw (14" Jet) for cutting metal.  The
apparent problem is that I can only slow it to about 1000 feet per
minute.  The largest pully that will work on top appears to be about 16"
diameter.  This still seems too fast for cutting steel.  Has anyone else
done this?  What other precautions should I take?  I will get a separate
metal cutting blade.

 - les

I try to mean what I say, but sometime I don't say what I mean.
Therefore, it is up to you to make sure that what I say is what I
mean.

My return mail address is incorrect to prevent spammers from getting
my real address.

Les Bartel
[email-masked]
VeriBest, Inc.  (A wholly owned subsidiary of Intergraph Corp.)
Huntsville, AL. (Corporate office in Boulder CO.)

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From: Michael Peele <[email-masked]>
Date: Mon, 10 Feb 1997 13:27:03 -0500

> done this?  What other precautions should I take?  I will get a separate

You don't have to use a slower speed to cut metal. I use wood speeds(3000 F/min)
and old blades. It's called friction cutting, well more like grinding. I have cut
1/8" O1 tool steel and 1/4" mild steel on my 14" Delta bandsaw. Blades not good
for anything else after a friction cutting session so I always use dull baldes.

Michael Peele

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From: [email-masked](Gerald Marquis)
Date: 11 Feb 1997 00:56:04 GMT

In <[email-masked]> Michael Peele <[email-masked]> writes: 
>
>Les Bartel wrote:
>> 
>> I've been toying.......for cutting metal.........
>  What other precautions should I take? 
>> 
>>  - les
>
>

If you decide to try friction cutting, make sure your saw is clean. 
Friction cutting is almost like torch cutting in that the high speed
blade heats the metal almost to the melting point and then drags it off
in a pretty good shower of sparks.  The build up of hot "filings" can
easily start a fire.

You might also try posting your original question to
rec.crafts.metalworking.

Gerry Marquis
Elyria, Ohio

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From: [email-masked] (Jonathan Waterbury)
Date: Tue, 11 Feb 1997 00:20:58 -0600

> in a pretty good shower of sparks.  The build up of hot "filings" can
 
I've wondered about this as well: What if one were to put a metal cutting
blade on a slowed down a Delta 14" bandsaw? How would that work compared
to a dedicated metal-cutting bandsaw? The friction cutting thing appeals
to me not in the least.

-- 
Cheers,
Jonathan

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From: Bill Pounds <[email-masked]>
Date: Tue, 11 Feb 1997 21:12:34 -0800

> to a dedicated metal-cutting bandsaw? The friction cutting thing appeals

Actually, most folks don't know that Delta builds a metal/wood cutting
bandsaw. I happen to have one. It is basically identical to the 14"
closed base saw, except that the lower wheel is driven via an oil bath
gear box. Even the casting in this area is very similar to the wood
cutting saw. But the wheels and guides appear to be the same on both.
The gear box has a push/pull knob that changes the gearing from direct
drive, for 3000fpm for wood, to gear reduced drive for 400-1000fpm (or
something like that), for metal.

All you need to do is figure out how to get enough reduction with your
pulleys to slow it down below 1000fpm. Then get yourself a metal cutting
blade and your in buisness.

-- 
Bill Pounds
[email-masked]

**********************************************
* Join the National Rifle Association today. *
*  The rights you save will be your own!     *
**********************************************

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From: [email-masked](Gerald Marquis)
Date: 13 Feb 1997 00:44:46 GMT

>blade and your in buisness.

I agree with Bill.  To cut metal, or anything, you need to move the
correct blade through the table at the correct speed.  To do true
contour sawing in low carbon steel (1010 to 1030) you need to saw at a
speed that allows any individual tooth to cut a chip of metal. 
Generaly, this would be in the 150 fpm range for 1/4" and up, 200 to
250 down to 1/8", up to 350 fpm for 1/16", and 400 or so for 1/32".   
Normally, in the thickness examples given above, you would use a 10
tooth above 1/4, and then a 14 tooth, an 18, 24, and 32 tooth blade as
you reduce in thickness.  Whenever possible, choose a blade that allows
you to have AT LEAST 2 or 3 teeth within the material thickness as you
cut.  If this is not possible, increase the speed a little so that a
tooth does not catch on the edge of the metal.  

When cutting softer metals like aluminum and brass, you can almost go
to wood cutting speeds and blade pitch.  Except for the rule of thumb
to keep 2 or 3 teeth within the material.  Cut most stainless steels
the same as carbon steels, you'll just move slower.

One final word.  Make sure there is no tooth protuding at the weld. 
This can cause blade breakage in any material but in metal it can be
especially bad.  If that tooth breaks off and gets embedded in the
material you are cutting, you can wipe out the whole blade in seconds. 
The vast majority of contour sawing in metal is done dry.  Sometimes
some beeswax is helpful in gummy metal like soft aluminum to keep the
material from building up in the gullet.  Sorry I've been so long
winded.  Good luck.

Gerry Marquis
Elyria, Ohio

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From: "G.I." <[email-masked]>
Date: 12 Feb 97 21:11:48 GMT

One of the problems you will run into when you try to use your tools for
metal and wood is that in most cases working with metal requires you to use
a lube or coolant which makes a mess that will have to be totally cleaned
up or any wood coming in contact with it will absorb the lube or coolant.
It can be done but be very careful about cleaning up after one or the
other. The problem with heat is also present it doesn't take much to ignite
wood shavings. I use my drill press for both and I built a plywood top for
use when I want to drill anything in wood.

Good luck!

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From: Dave Druckerman <[email-masked]>
Date: Wed, 12 Feb 1997 10:36:55 -0700

Bill Pounds wrote:
> so), for metal.
P.S.  I looked into the wood/metal cutting saw Bill is referring to
here.  They are virtually identical except for that gearbox, from what I
can tell from Delta's catalog.  They're even on the same page - you have
the woodcutting one and the metal/woodcutting one, and then all the
base, motor, electrical control, etc. options.  The metal/woodcutting
saw's cost was in the realm of $1400 to $1500 at the end of last year,
or about twice the cost of the equivalent 1 hp enclosed stand Delta
woodcutter.  As I wasn't sure if I would need/want the metal cutting, I
contacted the Delta technical support line to see if I would be able to
upgrade (basically add the gearbox and multi-step pulleys), and they
said they do not offer an upgrade.  When asked if the parts would fit a
14" woodcutting saw, the tech. support rep. just reiterated "Sorry, we
don't offer an upgrade."  

For the additional $600 or so, I've concluded that it's a better deal to
buy the woodcutter and then get a seperate metal cutting bandsaw.  For
the work I'm likely to need a metal cutting bandsaw for, something like
the Porter Cable or Milwaukee portable saws will do, and even with their
pipe-leg stands, I'm still dollars ahead.  Another alternative is a
metal cutting saw from Grizzley.  Their roll around saw (from their
metal working catalog) is even cheaper than the PC and Milwaukee
portables, and it can be raised to vertical and install a small table,
but I have no idea of the quality.  

Dave Druckerman

Just my .02 cents 
(yes, alas, with the instantaneous, cheap, global communication of the
Internet, I fear the value of my "wisdom and insight" has indeed
decreased by 2 orders of magnitude)

My opinion, not my employers.  

P.S. - Does anyone else's e-mail package and/or ISP not allow you to
post a message unless your newly added material is more than the old
information that is copied?  I keep getting an error unless I say more
than the sum of the previous posters, forcing me to be more wordy, or
making me snip much more than I would otherwise like to.

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From: Bruce Johnson <[email-masked]>
Date: Thu, 13 Feb 1997 03:00:56 -0800

It depends what you mean by "metal cutting". If you mean 1/4" aluminum,
1/8" brass, 10 ga mild steel, etc. you don't have to get fancy. I have a
cheap Enco 14" bottom-of-the-line woodworking bandsaw that I keep set up
just for cutting "sheet metal". I didn't even bother to change the
pulleys. I just set it up at the lowest speed it has, and put on a 1/4"
x 14 good quality metal cutting blade (I like Lennox). It works fine,
although earmuffs are a requirement!

Now, if "metal cutting" means 1" steel plate, that requires serious
horsepower and big stiff frame, well beyond most woodworking bandsaws.

BTW, I have a 14" Bridgewood (from Wilke Machinery) wood/metal bandsaw
with the quick change gearbox like on the Delta. It's a good sturdy saw
that's served me well for 15 years. The gearbox works fine, but I found
that I really never used the feature. I bought the Enco because I got
sick of changing blades back and forth!

Bruce Johnson
Johnson's Extremely Strange Musical Instrument Co.
Burbank, CA

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From: [email-masked] (Computer Systems Manager)
Date: Thu, 13 Feb 1997 20:10:45 +1100

[This followup was posted to rec.woodworking and a copy was sent to the 
cited author.]

In article <[email-masked]>, Les Bartel says...

> Huntsville, AL. (Corporate office in Boulder CO.)

Les,

I borrowed a copy of a book called "Using The Bandsaw" by Nick Engler 
>from  my local library yesterday and I think you should do likewise 
*before* you shove any steel through your bs.  The old adage that if it 
doesn't feel right then don't do it comes to mind when I think about your 
intentions.  So much for the safety bit.

The book has a section devoted to converting a single-speed bs into a 
four-speed job.  It basically involves replacing the single pulley with 
ganged, 4-inch dia., four-step pulleys on both the motor drive shaft and 
the blade drive wheel.  The four-step pulley diameters are 4", 3-3/8", 2-
5/8" and 2".  The drive pulley diameter is about 10"-12". ... a lot 
smaller than the 16" you were suggesting.  A v-belt joins them ... in the 
same fashion as the speed changer in a drill press.

According to Engler, this mechanism will produce outputs of about 2800-
3100 fpm, 1900-2100 fpm, 1100-1200 fpm and 680-750fpm.  He then goes on 
to list what speed settings to use for various wood cutting exercises and 
also lists speeds for cutting nonferrous metals, paper, particleboard, 
plastic and plywood.

I can't describe his detailed setup in this forum due to size obviously, 
so would refer you to Engler's book for the complete story.

Hope this helps,
-- 
Regards, Rick
In Oz
To email me first remove the * from the email address shown above.