Cutting angles for welding

[Rch]

Harv et al, I looked up the Porter Cable portable band saws on the net.<A target="_blank" HREF=http://portercable.com/cgi-bin/products.cgi?method=bytype&prod_id=METAL_CUTTING>http://portercable.com/cgi-bin/products.cgi?method=bytype&prod_id=METAL_CUTTING</A> I see 2 versions. I didn't even know there was such an animal. From looking at the picture I'm unsure if you can just cut off ends or can you cut a longer piece in the middle. Also how easy is it to cut a 45 degree angle exactlly? Also, what do they go for? Is a carbide chop saw a big improvement over the abrasive blade?
Brent, for sure I'm going to improve my band saw vise with a jig to cut a 45 degree angle.
It seems a power miter saw for steel would have a niche. Obviously, adapting a wood one is problematic.

 

[Egon]

I have used a reciprocating saw with metal cutting blade. It seems to do the job but may be hard to get a double angle cut started corectly.

Egon

 

[Anonymous Poster]

A couple of years ago we bought the top-of-the-line Milwaukee SAWZALL and I am AMAZED at the capabilities of this tool! I should have had one YEARS ago. It saws pipe, both mild steel and other materials, and is a super tool for cutting large diameter PVC. I haven't tried it because I'm pretty good with a torch, but I suppose I could "fish-mouth" a pipe with it if I needed to.....especially smaller diameters. I'm used to working with 6-8-10-12" diameter piping so I habitually use my GAS HATCHET for that kind of stuff.

 

[wroughtn_harv]

Morning Ray,

<A target="_blank" HREF=http://portercable.com/cgi-bin/products.cgi?method=byid&prod_id=725>This</A> is the one I've got and love. I paid two fifty plus tax and license if I remember right.

Btw, I have a deep throat Milwaulkee fresh out of the shop, not even plugged in since it got back, two hundred dollars. That's a hundred off what Lowes and HD want for it. I'll had a hundred to that and get me the deep throat Porter Cable.

There is some skill involved in operating a portaband. That comes with practice. I've gotten pretty lucky over the years at making straight cuts. Luck comes with even more practice.

A funny story, sorry.

I'm a competitive sort. An example would be when I was a cable splicer at the telephone company all the splicers made a big deal out of cutting pennys with their electrician scissors. I of course had to do it faster, just my nature. Then one day a big old lineman cut a quarter in half just cause he could to show me something I guess. Ever since then when a newbie would show how he could cut a penney I'd do him a quarter. I like to say I didn't know I could do it until I saw a lineman do it. And anything a lineman can do I can do, better./w3tcompact/icons/laugh.gif

Well, I heard a story some years ago about a french canadian fitter that couldn't read a tape measure but he was the best fitter to be found.

Ever since then when I'm fitting things up I try to avoid using a tape. I look at it and then try to make the cut. I've had some successes. But there have been some failures, we don't talk about them.

The point being that when you start cutting angles and doing stuff like coping pipe don't be afraid to trust your eye and instinct. One good thing about working with steel is you can fix a mistake and you're the only one that will know. I do it all the time./w3tcompact/icons/laugh.gif

But remember, it's a mistake if you catch it. It's a screw up if you don't.

 

[Egon]

Just add a pipe strecher to your tool supply and the misses can all be redone.

Egon

 

[Egon]

Do you use a jig for holding and moving the torch when you bevel pipe ends?

Egon

 

[Anonymous Poster]

There is a regular machine for bevel cutting the ends of pipe. It is a sort of clamp-around arrangement with the torch on a circumferential chain track. They do have a tendency to "fish-mouth" sometimes....especially on used and not-so-round pipe. We are talking diameters 14" and up. The little stuff is faster to do with a wrap-a-round; a chalk; and a steady hand on the Victor Journeyman No. 200 torch with number 00 tip.
You cut the pipe with the torch laying less-than-normal to the surface of the pipe and pointing toward the scrap end, and as soon as the piece drops off you beat the end of the pipe with a 24 OZ. ball peen....I prefer a VAUGHN...........hammer to establish a small flat area on the butt joint.

 

[wroughtn_harv]

For smaller pipe, two inch and smaller, I have mechanical knotchers. I have a Vogt that cuts two inch (2 3/8) schedule forty so fine. A weldor bud says it leaves a joint that even Ray Charles couldn't mess us welding.

Williams Low Bucks makes a mechanical knotcher that I've got set up for one inch, one and a quarter inch, and one and a half inch pipe.

The Vogt is much nicer a machine. But it cost four times what the Williams does but is worth it.

When I'm doing production knotching (coping) like I will today or tomorrow I use the plasma torch and a sure-fit guide because it's two and a half inch pipe. On pipe that's larger than that I usually make a sure-fit type guide myself from the next larger size of pipe than I'm cutting. I have found they pay for themselves if there's more than twenty cuts usually. Less than that I use the wrap around method or even the old guesstimator.

The only problem with the guesstimator is I've found it's really sensitive to moon--earth movements. When they move it messes up my wife's whacky adjustment which has a definate affect on me. Funny how that works.

 

[Egon]

Right on. The jigs get handy when the pipe thicness increases.

Egon

 

[Ken Kegris]

I have a evolution 14 inch cold cut saw 1400 RPM 300.00 new haven't changed the blade and bought it new in 2004 before retirement. Very little edge very little heat, lots of sparks and throws shavings all around the shop. I also have a band saw 6 inch and between the two along with the plasma cutter I haven't used the torch in years. I use the torch for cutting stuff like a tooth off a cutting edge where i have a lot of weld to skin away. Haven't done none now for years. I am getting to the point if I cant get it at my level or get it on the bench I don't want to do it.