Bandsaw vs cold saw

I'm probably going to open a question that sounds like the 'red states vs blue states' but I gotta ask:
I deal with a University Engineering proto shop that has a 8x12
horizontal band saw was inexpensive to start with, is getting pretty ratty, needs to be replaced. The question: cold saw or bandsaw? I'm pushing for a bandsaw because blade costs are so much lower.
The kicker: this shop is used by inexperienced users doing all sorts of known and unknown materials. Much of the work is not easy cutting of long sticks of hot rolled angle. More like short chunks of anything including stainless. I can't depend on them clamping the part correctly. I can't depend on smooth entry feed or even the right feed pressure.
To give you a feel for things: the Delta vertical bandsaw has a blade life of around 2 weeks, usually winds up missing most of the teeth after someone tries to cut some .120 stainless, snags the teeth. I'm afraid I'd be looking at sending in a $500 cold saw blade every other week. Not going to happen on my watch.
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wrote:

Roy:
I don't have any experience with a cold saw but PLENTY of experience with a bandsaw. We have the same situation, inexperienced students shoving anything through the saw, sometime a brand new blade can be demolished almost as soon as it is installed.
Band saw blades while not cheap are much more affordable in a student shop. Maybe a hands on demo with a sign off sheet before students are allowed to use the saw would help.
Good luck with a losing battle!
Errol Groff
Instructor, Machine Tool Department H.H. Ellis Technical High School Danielson, CT
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Errol Groff wrote:

You should see what happens in the machine shops which are open out of hours. I was in a postgraduate machine shop a while back, and there was a tiny vertical bandsaw there. One of those machines which is only really meant for cutting plywood. A guy was trying to cut a 5" x 3" cast aluminium ingot with the saw. One of those unmarked ingots which is full of sand. I told him that perhaps he should wait until the morning and use a more appropriate saw in a different shop, but no, the research project was too urgent :-).
A power hacksaw may be another possibility for your shop. They cut straight and the blades are a lot cheaper than cold saw blades.
Best wishes,
Chris
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Errol Groff wrote:

Sounds like what used to happen down the votech college in Wichita. I used to attend the machining evening class and someone in the day classes used to ruin the band saw blades in short order. It annoyed the instructors and on a number of occasions I ended up sawing 2" aluminium plate by hand because it was quicker than using the saw.

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I do not believe anyone that likes you will tell you to get the cold saw in your case.
Cold saws are neat when you know they will only cut suitable materials.
Wes
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I agee. Bandsaw it is. And a blade welder and boxes of blade stock.
Gunner
"They couldn't hit an elephant at this dist..." Maj. Gen. John Sedgewick, killed by a sniper in 1864 at the battle of Spotsylvania
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Jeez, there should be SOME consequence for somebody abusing the machine. You're not going to get him to pay for it, I'm sure. But maybe if his department had to pay, there would be pressure on him to do better. 'Course you'd have to know who the perp was & you probably never do.
I feel your pain, Bob
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    --FWIW I'd get the cold saw to supplement the bandsaw. I've had a cold saw for two decades and I'd be lost without it. Once you've got it and use it you'll find the bandsaw will last a lot longer due to its reduced work load. Heh.
--
"Steamboat Ed" Haas : Never thought I'd live to see
Hacking the Trailing Edge! : our "iron curtain" crumble...
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Pity that you have to choose, eh?
Altho a lot depends on what you make/setup you buy, a band saw does seem more practical in overall general use. The advantage to a cold saw is near-finished cut faces, high accuracy (.005 or better reproducibility in some cases), and nice centering vises, good for short material.
A properly set up band saw can give .015 reproducibility, but this is all proly moot in a proto shop.
On a band saw, once tooth loss occurs, you can stem its progression by dremel-ing a "ramp" from the no-tooth region up to the full-tooth region, so no more teeth break. I usually give about a 1/2"-1" "lead" up to full-tooth, on 1/2" 12-tooth blades.
If blade breakage is a problem, get a good blade welder. I've almost never had a blade re-break at a weld, and have used "patch-work" blades, of 10 or more welds, in 130" 1" blades. Of course, this won't help if the blade is simply dull all the way around.
Steamboat mentioned "lightening the burden", which is a very good point, esp. when you "match" saw to material. For example, a radial arm saw or chop saw with carbide can be great for aluminum, very nice cuts. Use progressive cuts depth-wise on thick wide alum. Sometimes this is the only solution for things like long length of 14" wide x 1/4" alum.
But the best supplement to a band saw -- an almost necessary one -- is a cheap chop saw with an abrasive blade (as thin as is practical, 3/32 being a good compromise), which serves as a very efficient and economical brute-force solution for "ugly" stuff -- thin crappy mat'l, drill rod, SS, hard to hold stuff, thin-wall tubing, you name it -- a god-sent solution that will save boucou $$ in blades, time, and misery.
You can also put an abrasive blade on an RAS, as well. I've done this to cut sheets of spring steel, using progressive-depth cuts as well, if thick mat'l.
It's best to push the RAS blade into the material, rather than pull, but you do what you have to do. You can also "rip" alum lengthwise on a RAS/carbide, for example, getting two pieces of angle out of channel, or channel out of tubing, etc.
Consider rigging up recirc. coolant if your saw doesn't already have it. Altho a bandsaw blade appears to run over-all cool, local tooth temps can get mighty high, esp. on SS -- watch the puffs of smoke come off SS, even on lite cuts.
Consider *two* cheapie band saws, one set up just for ferrous (steel, cast iron, SS -- fine-ish tooth and slowwww), and the other for non-ferrous (brass alum) -- the roughest tooth you can buy, at the fastest speed, which just whizzes through the material. This will overall save time and blades, because people just don't like changing belts and blades.
Also, consider using a VFD with a 3-ph motor, for much wider speed control. You may still need to change belt pulley settings, but not as often.
--
PV'd



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RoyJ wrote:

Hi Roy,
Sorry you're stuck with this, I've been re-treaded twice (part time) with the instructor stuff (vo-tech and university). I'd like to think I've more patience now, but shop habits either start early or come "HARD".
I'd go for the cheap band saw (most work), "and" the cold saw (precise potato chip thin error work), "then" a dry abrasive saw (for the beautiful sand pounding children, whom their parents enrolled at birth, can use) if they're not sure. I can just imagine myself starting the semester with that...
It's about shop habits, if your going to treat your workers well, your co-workers well, or keep your employer solid, you better know where your starting and going. A concept or design is not the start, or the end, in a "blink of an eye".
The best instructors I can remember always "set the groundwork of performance" and were taskmasters at your getting there.
"Known and unknown materials ????", tell the students there might be depleted uranium in the materials rack and see if they pay attention, and check before they grab it!!!! (and of course, know how to find out if it is, and how to work with it if they want too).
Matt
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Hey Roy,
There is a discussion "further up the page" here on RCM right now about abrasive cut-off wheels. Don't you have one or two of those dirty things for "students"?
Brian Lawson, Bothwell, Ontario. XXXXXXXXXXXXXXXXXXX
wrote:

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Nope. Too noisy, too dirty, too much fire hazard for the area. That and they don't seem to understand the difference between ferrous materials that cut nicely on an abrasive saw and aluminum that just clogs it up. Sigh.
I need to have a discussion with the materials guy to clue him in on subjects near and dear to my heart. What's funny is that he will be happy to cover the subjects I ask him about without any conversation.
Brian Lawson wrote:

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Brian Lawson wrote:

Watch it ... I just yesterday bought a 10" chopsaw and some 7" wheels ... because it's more accurate on square and miter cuts than my portaband-in-a-vertical-adapter . Used properly , an abrasive wheel can be a good choice . Used wrong , it can be a death sentence .
--
Snag
sometimes ya gotta
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I think I may opt for the cold saw, but add to it a key actuated switch so that you can have a modicum of control over it's use. That way you could eyeball the setup prior to the cut to be sure of things.
The cold saw works fine for stainless with the right setup and technique. It also is much faster than the band saw so monitoring it's use would not kill too much of your time.
--

Roger Shoaf

About the time I had mastered getting the toothpaste back in the tube, then
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