Any advice on cutting square tube?

[EmptyNester]

I am about as much of a newbie as you can get.

I've been practicing with my MIG and just recently got my Power Plasma 50. I've been able to test it and learn how poor technique can create a lot of blowback

My first project will be a welding cart. I'm going to use square tube for the cart, based on designs I've seen here.

I just wondered if anyone had advice on cutting square tube before I give it a shot.

Thanks!

[Rivets]

Empty Nester,

This will sound contradictory since you have a plasma cutter, but for square multiple cuts of the same length, it's hard to beat a metal cutting bandsaw.

FWIW,
rivets

[geezer]

As Rivits has said, cutting square tubing with a plasma is a poor choice, best to use a bandsaw, chopsaw and make sure you use a square to align the blades before you use them, accurate cuts can be done with either if you take the time to set them up. The PP50 can give good accurate cuts on plate if you use a guide strip, to get that on square tube you need to guide 4 sides, not worth the setup time for that when a chopsaw will give better results. The PP 50 is a great cutter that why I have one, I just don't use it for square tube unless I forced to.

One more thing; what should be discussed and hasn't been, is PREP AND FIT UP, GAPPING etc, prior to welding, precision cutting of material is not desirable prior to some welding joints, gaps are needed for proper welding in some cases etc..I'm sure we have some more experienced people on this site who add to the issue as to when to use gaps and other fit ups on different material thichness etc are required.

[jsclark4500]

You can use a chop saw, zip blade on a grinder, bandsaw, plasma cutter, etc. Remember that the mark of a true craftsman is thier ability to turn anything that is not perfect into a work of art. With wood once you cut something wrong you throw it in the scrap pile... with steel you can add more metal via the weld and correct for irregularities. You don't have to get the cuts perfect, just close. The weld and aligning closely will take care of everything else. Have fun and relax....

[DaveO]

In a pinch, you can get a metal-cutting disk to mount in a circular saw- about $4 at a Wal Mart near you. Eye and face protection STRONGLY recommended: since you're usually hunched over the saw I'd hate to have one go bad during operation.

[performance]

Or, if you get a regular discount or wish to smile real nice at the nice lady, you can get the nice thin ones that cut a whole lot faster at fastenal for 1.25 like I did yesterday.

[performance]

To get the MOST out of the PP50, turn the plasma down to about 30 amps. Then get a tri square (also known as a speed square or Johnson). Hold it on the mark, allowing compensation for the torch tip and kerf and use it as a guide. Just drag it across the metal. Flip the tubing and cut the next side. I've done several thousand feet of tubing cuts this way. Its fast and accurate enough. The thing to watch for is that your cuts will match up once you get to the fourth side. Starting on the edge and dragging toward you is safe and effective. With a little practice it will become a seamless motion. The torch arc should start on the radius of the tube, so it won't create much if any blowback.

[EmptyNester]

Most of the feedback drives me to think that a saw is the way to go - I just don't have a chop saw or a metal bandsaw.

I had been thinking that I'd make a wood template that I could clamp on the tube so that I'd get a straight cut across all the angles. I had thought that there might be an issue with starting since starting on the edge would give the entire height of the tubing.

[performance]

Both are tools I have at my disposal. Go get one (chopsaw) from HF for a song, and if you don't push it, it will last. If its small tubing a reciprocating saw will work. Shoot, even a good jig saw will do it. If you have a circular saw, you can by a metal cutting blade for it too. Works fine....Slow and messy, but works fine.

[everlastsupport]

I would use the horizontal band saw as my first pick. Chop saw would be second pick. Like mentioned, $99 and a 20% off coupon and you can pick up a chop saw at HF. A tool you will use a lot, like a bandsaw.

Plasma would be my last pick. Sawzall/reciprocating or circular saw would be in the middle somewhere.

[zoama]

I would get a $79 portaband from Harbor Freight and use the 20% off coupon. You can also make a pivoting stand for it to make it more useful. If you can afford it, a 4 x 6 horizontal is the best choice.

[Steve]

Another saw that is really excellent for cutting tubing is a cold saw. No sparks and very accurate cuts. I have one and I use it for cutting any type of tubing or angle that I need to cut. It uses a coolant to keep the saw blade and metal nice and cool.

Cold saws can also do compound angles more accurately than most any other saw. Sort of a metal miter saw.

[acourtjester]

Hi
Since a newbie asked I’m going a little outside this post to inject my opinion.
I hate chop saws and will not use one I do use a cut-off blade in an angle grinder as little a possible. I have used up a few band saws and a great number of blades for them. They produce residue that is very controlled and if the blade breaks it no big deal.
Chop saws produce great volumes of dust, sparks and smoke that go everywhere. That stuff is bad for your health, it stinks and in some instance could be a fire hazard. Start off right and buy a metal cutting band saw the cost is not that much more and the blades last longer if you get good ones.

Have fun
Tom

[zoama]

I agree with acourtjester... chop saws stink and mess up your whole shop. I'd rather jump off the empire state building head first into a thumb tack than use a chop saw.

[performance]

They have their place. They are good for cutting solid rod stock and square stock. Also pretty good on small gauge tubing and pipe. But don't go over 3/16" wall thickness or you are looking money and time. Plate thickness are off limits.
When used correctly, they are quite efficient. One thing that many people are not aware of is that they have a THIN and THICK version of cut off blades. The Thin ones are much faster, create less dust and they are more accurate. The thick ones though it sounds counter intuitive like to walk with me on my old DeWalt.

[EmptyNester]

ACourtJester,

Thanks for the insight on the the various degrees of mess. Since I work in an attached garage, that is really a consideration.

It does sound like a bandsaw is the way to go.

Rege

[performance]

IF you want a good one for a cheap price, here is the one I bought to use. (and subsquently loaned out my taiwan made HF to a friend). The metal never moves to cut angles. That's a space and time saving feature. The head does and it has a nice cam tightening vice. After having the kind you have to swing the metal all around its very nice, and angle cuts are made accurately with a degree by degree scale and pointer. The ONLY complaint is that the idler wheel is a bronze bushing instead of a bearing...But the guides and everything are much heavier. I think the bushing is oil impregnated, but I put a shot of lithium up there every once in a while anyway. So far no problems...Oh and when/if you get it, it can be coaxed to cut 6 inches. http://www.agrisupply.com/product.as...6103&sid=&eid=

[Steve]

If you are doing plate steel, sheet steel or aluminum or any other plate or sheet that is conductive, then a plasma cutter is the way to go. For tubing, angle and rod, plasma cutters just aren't designed for that type of cutting.

I have a friend who owns a fabrication business and I asked him what he cuts his bar, angle and tubing stock with. I expected to hear a megabuck band saw or a 3 phase liquid cooled cold saw. His answer really surprised me. His shop has 8 Evolution Rage 2 cold saws.
He said that he could have invested well over 5K on a water cooled cold saw but it would have slowed down production for each man as they would have to wait to get on the saw.
And a breakdown on one machine would stop production. So he bought 8 Rage 2's and is really happy with them.

Here is a Youtube link to their video on it......http://www.youtube.com/watch?v=JyPT2...eature=related

The Rage cuts without sparks or coolant and uses a special blade that lasts for over 1000 cuts. It has a 3 year warranty including the blade. It can do compound miter cuts and is extremely accurate with no machining needed on any cuts. Very, very smooth cuts.

Here is the link......http://www.evolutiononlineshop.com/s...t%20Off%20Saw/

For around $420, I think it is a great deal. It's next on my list of tools to have. I found that Sears also carries it for $269. My friend would have a fit if I told him that! He paid $325 each for his 8.

Those abrasive chop saw blades add up and the sparks are a real pain in the you know what. Band saws are nice but take up space. The metal cutting blades on a band saw aren't cheap either.
I also like the portability of the Rage.

A way better way to cross cut metal than a band saw or a chop saw.
Just my opinion of course!

BTW...I do not work for the Evolution company, have any stock in it or are related to anyone who works or owns stock in that company. If it was a POS, I would say so.

[acourtjester]

Mark I have one of those band saws too plus the normal 4" X 6" it is a very good saw. I keep the normal one as that one will not go to verical but it is better to cut angle cuts with. Mine is a different brand (tjl industries) same saw. I think it is better made that the normal 4" X 6".
have fun
Tom

[acourtjester]

Thanks Steve
Sears still has those evolution saws on sale and over the holiday you get free shipping. I got one comming for $279. with tax.
You can never have too many tools.

have fun
Tom