Cutting accurately enough for welding joints

"gwpm57" wrote: (clip) I'd like to invest in another method of cutting steel that will give me nice straight accurate cuts. (clip) ^^^^^^^^^^^^^^^^^^ I'm a lot like you, and I have found a good answer: spend a couple hundred bucks on a Portaband or Milwaukee hand-held, portable band saw. It will cut most anything you need cut, and it has the advantage that you carry it to the work, instead of vice versa. This means that after an assembly gets too bit to fit on the table of a stationary band saw, you can still make cuts easily. And it takes NO! floor space.

BTW, out of curiosity, I bought one of the el cheapos from Harbor Freight. Not much good--I have stopped using it.

Absolute shizz would be a cold saw. Way way way way out of your price range. What most guys do:

A good quality horizontal band saw is nice but quality goes along with price. I have a little cheap import and wished I had spent 700 to a thousand on a better one that cut faster and had a protractor head. A blade that is 3/4 wide is a lot more rigid and does not wander as much. A coolant system is needed for long life. Don't give up on an abrasive chop saw. It has been my experience that people go for the cheap abrasive discs and then get poor results. The thinner the blade the less power is required for the cut. The thinner blade has a shorter life but is less likely to wander off its cut. For accuracy my preference is Walter brand. The cheap discount discs just don't do it especially with angle cuts on small pipe. Randy

Thanks, Bob

Also, with these saws, quality of cut depends on how well the object is being held to the base. Those saws with more rigid bases get better results.

VERY true. Ive a decent protractor head Kalamazoo, dual fast action clamps, will go 45' in each direction, 10" blade..and the cheapy blades suck big time. Put on a quality blade, 1/8" or thinner..and I can do brain surgery with it.

Gunner

"If I'm going to reach out to the the Democrats then I need a third hand.There's no way I'm letting go of my wallet or my gun while they're around."

"Democrat. In the dictionary it's right after demobilize and right before demode` (out of fashion).

-Buddy Jordan 2001

Are you sure your problem is with the cutting? Joints that are both strong and pretty can be made even with torch-cuts. Sequence of welding to control distortion makes more difference in carts, shelves, racks etc than precision cutting. Careful thought to what the metal will do when the joint cools and shrinks is the key. Tack, check, bump, tack some more, check again, bump again, then clamp to expedient jigging and run final beads.

Useful aids to persuasion include a really big brass hammer and occasionally a 10-ton portapower....

I also agree with the recommendation of a Milwaukee or Porter-Cable portable bandsaw. I have a Milwaukee. It's one of the most useful tools I own. Reports differ on the efficacy of the HF knockoff: some have found the cheapo satisfactory while others have not.

Here's the best bandsaw made for your application:

Your projects sound like many of mine, and I suppose many other RCMers. I have the 4x6 horizontal-vertical bandsaw ($150 from a Homier tool sale), and it has proven to be a very worthwhile tool. These models generally need to be tuned and adjusted to get good results, but I then I usually disassemble everything I get anyway.

They aren't very comfortable to use in the vertical position, but they work OK. The small frame size limits the size of material that can fit between the blade and the housing, to a fairly small dimension. The blades are 1/2" wide, so the cuts will have to be fairly straight, not intricate curves. They're great for cutting lengths of stock in the horizontal position, relatively slow but quiet, and no sparks, flying dust or smoke.

Your saw ought to be accurate enough for the work you've described. Perhaps there's something wrong with it. For example, my 20 year old import abrasive chop saw recently began making crooked cuts. The circlip had come off the pivot pin, which had moved slightly sideways causing a bit of extra clearance. One tap with a hammer and it was back to normal.

When cutting angles I often use a piece of scrap to keep the blade from sliding along the work. Otherwise, a little sliding can cause considerable blade bending and a crooked cut. The effect is hardly noticeable on small stock, but gets obvious with thicker stuff.

Still, as someone mentioned, you might consider modifying your fitup technique.

I have one of the usual cheapie 4X6 band saw. Wouldn't want to be without it, but I consider it a last resort if speed or straightness is needed.

Just bought a Dewalt DW872. Very cool, lots of nice features. If I had to choose between the abrasive, the cold saw and the 4X6, it would be the cold saw. In case you consider getting one, here are some notes - no matter how it's adjusted, the rear jaw of the nifty multi-position vise doesn't lock down as securely as I'd like. I'll probably modify it. And the moveable jaw has sufficient up and down play that when the vise is shut, the material can float slightly if there's any tension on it (like when you have a long piece that isn't supported perfectly). The manual warns to use the aux hold-down clamp every time, but it generally can't be used unless the vise jaws are more than an inch apart. Like most chop saws, the miter markings are too crude. Easy fix is to dial in the position, then scribe lines on the base around the rear jaw. Chips produced by the saw seem to get in the way a lot - keep a blow nozzle handy. $406 delivered from here

It would be a nice addition to the chop saw. When I visited a friend recently he was using a good-sized horizontal with a coolant system to make a bunch of real simple chops of 2" pipe. Since it was obviously taking too long, I asked why he wasn't using his Makita abrasive chop saw instead. He said it had started cutting crooked recently.... turned out the pivot hold down had become bent, apparently because someone had been slamming the saw against the up-stop.

Wayne

--FWIW you can't beat a cold saw. There's at least one brand and maybe two by now that cost less than $1k. The only thing they can't do is really thin stuff like wire and for that a hacksaw does fine.