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Evan
01-08-2005, 12:22 PM
I just got the new Sears tool catalog yesterday. On the cover is a tool I have never used, what they call a twin cut saw. It is a worm drive saw with two counter-rotating carbide blades that run directly against each other sanwiched together. They show it freehand cutting a hefty thickwall piece of square steel tubing. Anyone used one? Any comments?

doug931
01-08-2005, 03:23 PM
Evan, I wonder if this is the type of saw a lot of the local fab shops have started to use. The one I have heard the most about is made by Milwauky,A portable metal cutting skil saw. It apparantly pushs right thru 1/2 steel plate. A couple of my welder friends use it to cut up 1" deck grating. Imagine what it can do on alum plate. Doug

John Stevenson
01-08-2005, 04:22 PM
Not heard of these Evan but there are hand held saws with special tipped blades 'very' similar to wood saws made for metal.

A friend of mine has a couple, one is a hand held and he uses it to cut sections out of barges and weld new plates in.

The second is a snip saw, like the wood ones but these have a simple vise on the bottom.
They run at about 3,000 rpm make a very clean cut and leave minimum burrs, unlike the abrasive saws.
When I last visited he was cutting 3" x 2" solid steel for toolholders. Took about 30 to 45 seconds to cut and left a nice clean cut.
The type you don't have to clean up if you don't want to.

John S.

Thrud
01-08-2005, 05:12 PM
Evan

I have heard of them but I have not used one. They are supposed to reduce the chance of kickback while increasing cutting speed and are much safer as a added bonus. They are higher maintenance and the blades are really expensive to replace. I don't think they were designed for metal slitting operations (such as roofing and heating/AC) but they may work fine in that application. Just an major upgrade to the old worm drive saw...

The new Titainium Carbide cold cut saws for steel that are out now are about $500 for just a blade but they are a big improvement over the abrasive chop saws - if you flood coolant on them (you have to make sure your saw is made to use coolant first - most can only run dry!) produce clean cuts that are not work hardened otherwise heating can increase hardness on ferrous alloys and make machining difficult - watch out for this!

[This message has been edited by Thrud (edited 01-08-2005).]

JIMofalltrades031
01-08-2005, 08:23 PM
yeh, I think the idea came from some tool outfit in Australia. They had a reciprocating saw with opposed blades shaped like scimitars. I will try to find the link I had. They were really proud of them to the tune of 700 or 800 aus dollars. I used the craftsman in the catalog to cut L-channel for motor fuel tank cages. Works but I didn't think it was very strong. Plastic casing and I think nylon type gears.

wierdscience
01-08-2005, 10:32 PM
I have seen several of the 14" cutoff saws that use the carbide blade.Ther are similar to the regular abrasive types,but are built heavier and run only 2500rpm.
Local steel supplier uses them everyday.He says they make between 60 and 100 cuts per day in structural steel up to 4x4x3/8 sqaure tube.The cut is better than the abrasive and nearly cold.The other advantage is the blade doesn't shrink.
Disadvantages are they don't like thin walled(<1/8")sections,an you don't dare use it on mystery metal.
He also told me the baldes last about a month before sending them out for sharpening.

Blades run $125-175 and the saw itself is $425
Haven't seen the Sears saw in action yet,but I'm beting it's gonna be crap,like most Sears stuff these days.

John Stevenson
01-09-2005, 12:55 AM
I think we are talking different machines here.
take a look at the Makita range.
These run at about 3,000 rpm will cut thin tube up to solids.
Blades cost about 25 to 30 UKP here which should work out about the same in $$ as you get thngs cheaper in the US, more buying power.

The blades cannot be sharpened it does say so on them.

The snip saw type blades ast a lot longer then the hand held, probably due to being more rigid.

I have looked at these and I'm impressed, if I did more fabrication type of work than large solids for machining I'd get one in a heartbeat.

John S.

CCWKen
01-09-2005, 01:51 AM
That must be for the Canadian Sears only. "They" won't let us have stuff like that here unless it's covered in so many warning labels you can't find the switch. http://bbs.homeshopmachinist.net//biggrin.gif

Have a number? I'd like to see that.

Evan
01-09-2005, 02:34 AM
The thing that interests me is the counter-rotating blades. I have been considering building an abrasive chop saw but it is limited in that you have to bring the work to the saw. This has potential. I suspect that Dave is correct and the blades are probably very expensive. But, I won't use it every day but if I do it could be very handy. The counter-rotating part should mean not just low "kickback" but NO kickback. Since it is cutting in both directions at once it should equalize the forces and just chew through the work.

Here is the front cover (NOT an ad for Sears, but I am sure they won't mind).

The Canadian catalog number is 092 821 580

BTW, they advertise the case is aluminum, not plastic. It weighs 11 1/2 lbs. Also, a realistic HP rating, 1.25hp. Two year warranty.

http://vts.bc.ca/pics/tsaw11.jpg

[This message has been edited by Evan (edited 01-09-2005).]

Mike Burdick
01-09-2005, 03:15 AM
From Sears:

http://content.sears.com/data/product_images/009/26829/00926829000-190.jpg

Craftsman 6-1/8 in. Circular Saw, Twin Blade Cutter (http://www.sears.com/sr/javasr/product.do?vertical=TOOL&pid=00926829000&adCell=P11)


_______________________________


[This message has been edited by Mike Burdick (edited 01-09-2005).]

Evan
01-09-2005, 03:43 AM
Hmm...

Thanks for the link. Replacement blade set is $50.00 bucks for a pair. I think I just might build a cutoff saw instead. Now I am thinking of using that three horse 3ph motor for my rotary phase converter as a cutoff saw. If I set it up right it can do both at the same time.

hoffman
01-09-2005, 08:05 AM
Buddy of mine got one for christmas. We experimented with some 3/16 plate and it ripped through it pretty good. Supposed to be good for 1/4. It left a pretty smooth cut on the 3/16 with no burr. The deal you see in the pic sticking out the top of the guard is a lube stick for cutting aluminum. The ad looks like he's cutting steel and they don't recommend lube for steel...
Seems to be an OK tool but I didn't want to run out and get one.

------------------
Hoffman in Warner Robins Ga

JIMofalltrades031
01-09-2005, 10:55 AM
we get the "high impact glass filled nylon" here....

http://www.sears.com/sr/javasr/product.do?BV_UseBVCookie=Yes&vertical=TOOL&pid=00926829000&tab=spe#tablink