cutting stainless

hi,
Some questions on cutting stainless. I have an angle grinder with an
attachment for cutting metal, it's probably a bit dangerous but it works
well. I can get extra thin disks suitable (and advertised) for cutting
stainless, but I wondered about the heatlth risks. It doesn't seem that
healthy to breathe dust containing chromium and nickel which has burned.
The same question about using a plasma torch.
Second question, can anyone suggest a cheapish method for cutting 3 mm = 1/8
inch stainless sheet? I don't want to cut that much, but a bit more than
would be comfortable with a hacksaw.
Thanks,
Reply to
Peter Fairbrother
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Bring them to a shop with a decent shear?
Electric or air shear?
Regards, Joe Agro, Jr. (800) 871-5022
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V8013
Reply to
Joe AutoDrill
Negligible. If the thought bothers you, wear a dust mask.
Can be more of an issue, as there are more fumes. Do this in a well ventilated area (like outside) and you should be fine.
Straight cuts or curves? For straight cuts, you could try a cut-off disk in a circular saw held against a straight-edge (board or piece of angle) clamped to the metal.
For curves, a metal cutting blade or a "Remgrit" carbide abrasive blade in a handheld jigsaw, or maybe the largest size (B3) Beverly shear.
For speed and simplicity, a plasma cutter looks like the best solution. Again, you can get very straight cuts by running the torch head along a straightedge clamped to the metal.
--Glenn Lyford
Reply to
glyford
Breathing burned chromium (CrO2) is undoubtedly better than breathing elemental Cr, which is extraordinarily toxic. OTOH, burnt zinc (welded galvanized) is much more toxic than likely elemental Zn dust is. But no dust/fumes is the best dust/fumes. Ergo, shearing often roolz. They make electric hand shearers for sheetmetal workers. Ones that could handle 1/8" SS are proly perty pricey, tho. ---------------------------- Mr. P.V.'d formerly Droll Troll
Reply to
Proctologically Violated©®
As far as shearing; stainless is a major pain to shear unless you have a VERY rigid, heavy shear with sharp knives. Forget about the HF Shear/Brake/Slip Roll, It won't cut anything thicker than .010 stainless, and then, not for the full cut length. The knives flex and the material just folds between them. JR Dweller in the cellar
Peter Fairbrother wrote:
Reply to
JR North
Tell me about it. After losing bids for nearly a year, I just scored this one on Ebay:
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Tracking by UPS says it will get here tommorrow. Can't wait for my new toy.
Karl
Reply to
Karl Townsend
On Thu, 14 Apr 2005 20:38:09 +0100, Peter Fairbrother wrote something ......and in reply I say!:
You should at least wear a dust mask for all this work. The cutting wheels are putting out bits of grit/glass/glue/binder all over the place. It's bad for you in any context. I doubt the fumes from cutting with a wheel would be very great.
Plasmaa could well be different. Here you should probably be looking at a fume mask, or make sure the output is blown or sucked away.
With a cutting wheel in an angle grinder? Actually a circular saw is a lot safer. Tough on the saw, so buy one that is either built for it or cheapish, and be prepared to rebuy. ****************************************************************************************** WHY _ARE_ WE HERE?
Nick White --- HEAD:Hertz Music
remove ns from my header address to reply via email
!!
Reply to
Old Nick
This may be obvious, but safety is important.... If you use the thin type of cutting disc, be very careful not to put any side/twist force on the disc, they can fracture pretty easily. A firm grip and face mask are a must.
Good Luck.
Reply to
Derek
I have a couple of diamond cutting disks (which came with the grinder) which I haven't used. I was told not to use them on steel, though I was also told it would be okay to use them on other metals. It doesn't say anything about what you can or can't cut with them on the disks or in the instruction booklet though.
First, is that right? And second, even if it is, could I use them on stainless?
Thanks,
Reply to
Peter Fairbrother
On Sat, 16 Apr 2005 01:23:22 +0100, Peter Fairbrother wrote something ......and in reply I say!:
Don't know, but if they're not for steel then they are probably not for stainless. I was warned that it is easy to damage diamond disks if you cut metal with them.
There are special "iron free" abrasive disks for stainless.
****************************************************************************************** WHY _ARE_ WE HERE?
Nick White --- HEAD:Hertz Music
remove ns from my header address to reply via email
!!
Reply to
Old Nick
Stainless steel is still steel, so don't use your diamond disks on stainless. The reason is that diamonds are a form of carbon, and carbon will disolve in steel ( low carbon steel, high carbon steel, cast iron all have carbon disolved in them. )
Dan
Reply to
dcaster
Okay, thanks.
So what happens when you try? I'd guess the sharp corners dissolve first, and the whole surface is smoothed. Grit size gets large, but it doesn't get any softer - does that stop it cutting?
Just curious now,
-- Peter
Sweet dreams are made of Anything that gets you in the seam And I feel like I'm Seventeen again. Eurythmics
Reply to
Peter Fairbrother
Some context - these are 4 inch metal disks with perhaps 20 1/8" slots in the outside edge. How fast will the diamond dissolve? They didn't cost me anything, but I wouldn't want to waste them.
I have used diamond files on HSS tooling - I haven't seen anything like dissolving diamond there, but could be I haven't done it enough.
Also, if you were to use diamond on cast iron, it would already be saturated with carbon*, so in (simple) theory no more carbon would dissolve - so can you cut cast iron with diamond?
Still curious :)
*
if i am not wrong - the white zone is for laoding and unloading only - if
-- Peter Fairbrother
Plagiarise! Let no-one else's work evade your eyes! Remember why The Good Lord made your eyes! So don't shade your eyes, Plagiarise! Plagiarise! Plagiarise! .. only be sure to always call it please research
T Lehrner^H^H^H^H^H^H^H Lehrer
Reply to
Peter Fairbrother
[ ... ]
It will dissolve fast enough so you would count it as wasting them
You aren't generating enough heat. There is *lots* of heat at the point of contact with a powered wheel, since the points are so small, and moving so fast. *That* is where the diamond dissolves.
If it were a very slow moving wheel, ideally with a flood of water coolant, you probably would have very long life.
I would not bet on it. At those temperatures, the carbon already in the cast iron would burn away, thus making room for more. Besides -- the carbon in cast iron is not alway evenly distributed, so there is plenty of low-carbon iron available to grab your diamonds.
Note that things like the Drill Doctor use a diamond wheel with HSS drill bit -- not because it is better for HSS, but because it lasts long enough in that application, and it allows them to say that it can be used for sharpening carbide tipped masonry drill bits, too. Otherwise, CBN (Cubic Boron Nitride) would be a better abrasive for the purpose.
Go ahead and try one -- and tell *us* how fast it dulls.
Enjoy, DoN.
Reply to
DoN. Nichols
Drill doctor may be a bit more cunning.
Normal grinding speeds are about 6,000 FPM and at this speed the wear rate of diamond grit against steel is pretty prohibitive. However if you drop the grinding speed to about 1,000 FPM the peak temperature and reaction rate drops drastically. It still grinds steel at a reasonable rate but now with an acceptable wheel life. I don't know the surface speed of the Drill Doctor wheels but I expect it's nearer 1,000 than 6,000FPM
Low surface speed is why diamond files and diamond dental burrs work fine on steel. Your 4" discs should be fine at about 1000RPM.
Jim
Reply to
pentagrid
[ ... ]
O.K. Let's find out:
RPM (unloaded) 4250 (G.R. Strobotac) Diameter (over grit) 1.2485" (Starrett digital calipers)
Circumference; 3.9223" or: 0.3269 feet
SFM (calculated) 1,389.14
So -- your guess is not that far off -- and may even better during loaded grinding -- I opted (lacking more than two hands) to measure the RPM unloaded only. :-)
If he has anything to drive them that slow.
Enjoy, DoN.
Reply to
DoN. Nichols

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