Goodbye To Garbage

[neptunebob]

I do see that you can still get the "batch feed" - although I have never seen one in real life. I just thought HD would have them because they sell all other GE appliances. You think it still has the "Carbolloy cutter".

Oh wait, Carbolloy is probably what they use in their jet engines.

 

[jamiel]

You can order GE disposers from HD. I did and they are shipped right to your door. I put in one of them with a ISE air-switch last year.

 

[tolivac]

GE "Carboloy" was a material that GE made and was used in machine tool and lathe cutters.GE fabricated cutters for lathes and milling cutters and other machine tools for machining all types of metals.It was some stroke of genius that someone in their appliance dept thought of using that tough, sharp GE "carboloy" as a disposer shredder cutter.The Anehiem machine don't have Carboloy cutters-sure wish they did!!

 

[sudsmaster]

Carboloy is a trademarked name for a type of carbide used for making metal cutting tools. There are many types of carbides in use today; Carboloy is a tungsten carbide with either nickel or cobalt as a "binder" to hold the relatively brittle tungsten carbide particles together.

Carboloy was developed by GE in the 20's. It is also the name of the company Carboloy that spun off from GE, and which now makes many types of carbide cutting tools and inserts.

Carbides are extremely hard and make excellent cutting tools. Their one weakness is that they are not very heat shock or mechanical shock resistant. Heat shock wouldn't be an issue in a food disposal. Mechanical shock might be a problem if a metal utensil gets down there. But usually even the broken edges of a carbide tool are still sharp - they might not hold tolerance or give a good finish any more, but who cares if macerated corn cobs don't have a good finish?

I'm not sure but I'm assuming that Carboloy has better mechanical shock resistance than other carbides.

Other choices for disposal cutters might be various tool steels, which are by nature more shock resistant than carbides. However they are not as corrosion resistant as carbides.

I have shattered a number of carbide tool bits/inserts just by light mechanical impact. I've even burnt some up by running them too fast through too hard a substance. But they are practically indispensible for machining nowadays.

 

[sudsmaster]

Here's a link to a good discussion of carbides and tungsten carbide...

What Is Tungsten Carbide Used For?

Tungsten carbide is a strong, durable material used across various industries, from mining to electronics. Known for its high wear resistance, it has applications in cutting tools, wear parts, and coatings.

www.azom.com

 

[tolivac]

From disposers to carbides-interesting.When I worked in a tool repair-and sales store(industrial and commercial tools)They sold hammer drill bits that had carbide tips for drilling thu concrete-besides the rotating action-there was also hammering action applied to the bit as well-that grade of carbide had to be impact resistent as well as maintaining a sharp cutting edge-another instance of impact reistence-the use of tungsten carbide for armor peircing shells and bullets.Tungsten is safer for this application than Depleted uranium projectiles used now.Both of these materials work well for blasting thru tanks bodies becuase of their hardness, and weight.Another use of impact resistence is in the use of carbides on rescue saw blades and saw chains.Remember the show "Emergency"? and the "K-12" gas circular saw they used to cut thru various things to rescue victims?These machines can also be equipped with blades that have carbide teeth for cutting thru most non-ferrous building materials-and yes they can cut thru nail embedded wood.Similar circular saw blades are availabe for coomon circular saws-often called "renovation blades"Another trait of these blades is their negative raked teeth.Another carbide blade for circular saws is what is called a "carbide chip" blade-very large blocky,sharp peices of carbide are fused to the rim of the blade.These are also very aggressive in cutting most materials-except stone,brick,or masonry.Diamond or silicon carbide blades are need for these.
Another thing on carbides---safety issue-esp for you saw sharpeners out there-you can sharpen carbide saw tips and other carbide tools with diamond or silicon carbide wheels-just be sure you DON'T breathe the dust-the dust contains the cobalt which will serously damage your lungs.I know of a saw sharpener that went out of business due to cobalt poisoning.His equipment was sold at the "ReTool" store here.I just remember "Carboloy"This is the instance I first saw it-besides disposer cutters-was the replaceable metal lathe tool cutters and replaceable teeth for milling machine cutters-for machining various types of metals-We used them in our High School metal shop.The instructor cautioned the tools were expensive and had to be treated carefully-besides brittle the tools were sharp-esp the mill cutters-you had to handle them with a rag-or they could cut you.The edges on the mill cutters were honed to near razor sharpness-and maintained it even after cutting steel.Just so long you didn't overfeed the cutter or drop it.

 

[sudsmaster]

Well, yes, carbide cutters are sharp, and I generally get at least one cut a day from either a carbide cutter or a burr or something. And, while carbide can cut steel far longer than a tool steel like M2, it will wear in time. Usually this is in form of chipping of the cutting edge, rather than blunting type of wear you see with a tool steel. Usually the chipping will take place because the rpm's are too slow, but it can also occur from thermal or mechanical shock. The former when cooling is uneven, the latter from intermittant contact of cutting edge with work. Both occur when milling metals, it's the nature of the operation, and it's much harder on the cutting tool than, say, lathe turning where the tool bit is in constant contact with the work. But basically all cutting tools and inserts are considered consumables in the machining trade. Many can be resharpened but I don't think anyone bothers to resharpen carbide inserts. Not worth the time.

Add to that the fact that no two machinists will ever agree 100% on how to run a cutter... luckily the specs are loose enough to allow for quite a variation in feeds, speeds, and depth of cut. There are also mfg recommendations for just how to handle various cutters for various materials... although in the shops I've worked people tend to do some trial and error and stick with what works.

If I can get the shop time, I'm planning on fabricating new lid hinges for the KA/Hobart KD-2P portable dishwasher I've been working on. Because it's stainless, I will likely use carbide cutters, although a tool steel will handle it also, just at lower speeds.

 

[tolivac]

Many woodworkers claim that a sharper edge can be honed on steel tools-but the carbide ones will maintain their edge longer.Its true that the carbide tool inserts were usually replaced when nicked or dull.I did only a little machining in the school shop-none since then.I have used carbide saw blades A LOT-the best out there.And some sawmill circular and band blades have replaceable carbide teeth(the circuilar blades)the band blades they are brazed on.For sawmill applications-its a tough job-the teeth may encounter nails,rocks,bullets,"spikes" put in by some folks to "sabotage" lumbering operations.

 

[sudsmaster]

At one time, all carbide edges were brazed on. The industry moved to replaceable inserts that are manufactured to such close tolerances that they can be replaced with a simple turn of a screw or two, and the cutter will still maintain the same tolerances - usually within a few tenths of a thousandth of an inch (for comparision, the average human hair is 3 thousands of an inch thick). Machining equipment (like CNC mills and lathes) is expensive, and the labor doesn't come all that cheap either, so if a cutting tool insert can be renewed in a few minutes and production basically uninterrupted, then that's a savings.

It's possible that some carbides can't take as fine an edge as a good tool steel, due to the brittleness factor. Add to that most woods are not uniform, so I guess you have a defacto partially interrupted cut, which can further stress the edge. This is probably true of hand tools for shaping and whittling. This is probably why we don't see too many carbide razor blades. But I've got the same carbide tipped blade on my circular saws for seven years now - they just don't seem to wear out anywhere near as fast as the steel ones do. Not that I do all that much wood working, mainly 2x4's to build up structures and such. The steel blades seem to have a finer kerf, though, and that can be handy when material is as a premium.

 

[tolivac]

anogher place for the carbide cutting inserts---stump grinders-when I had some trees cut down a awhile ago-the sawer used a stump cutter to grind the stumps-it had carbide cutters on the cutting wheel.He could replace them when they got really dull or worn away.Like as Sudmaster said-the carbide could still have a sharp edge when nicked-of course good enough for shredding corncobs or grinding stumps.I also found reference to a flail mower-crop shredder that carbide edged cutters.It was used to cut and shred the crop remains so they could be plowed under after harvest.A similar mower is used to mow roadsides.I just wonder what happens to the carbide edged flail knives when they hit a rock!!

 

[sudsmaster]

Rocks may not be as much of a problem as hitting steel. Rocks are brittle too, so they may give before the carbide does. Steel is generally very tough, and carbide seems to break quite readily if pressed too hard against it.

The cutters in the video look quite beefy, however. More like rods. A lot of metal cutting carbide tool inserts are also slab-sided, to help prevent chipping, among other things.

 

[tolivac]

You can get thin kerf carbide saw blades now-they are really nice esp for my older Shopsmith--puts less load on the motor.The blades are from DeWalt.Got 'em at Home Depot.The kerf is a scant 1/16 in wide.Unbeleivable-and nice cut.On one of the blades-'rock Carbide" it could cut nails or screws in the wood.Have it on the machine-cuts well.
On the Flail mowers-rocks could cause the blades to dislodge from their chain mounts-the thick rubber guards on the front and rear of the mower unit is there for a good reson-not only from objects hit by the knives-also in case a flail knife gets loose and "thrown"I would be concerned carbide chips could be projectiles-that would be a concern if you were the tractor driver.On side mount mowers-a thick peice of plywood covers the engine and operator side of the tractor in case something is thrown in the engine or operators direction.These types of mowers are common here-for mowing ditches-could be flail or swing knife rotary.Both are powered by hydraulic motors.I haven't seen carbide edged rotary mower blades.

 

[sudsmaster]

Well, it all depends on the grade of carbide and how it's shaped.

By way of example, a carbide masonry drill will disintegrate rapidly if you try to drill a hole in steel with it.

A carbide metal cutting drill bit will disintegrate quickly if you try to cut a hole in cement with it.

 

[tolivac]

The carbide tips in some carbide tipped core cutters for rotary hammer drills are rated to drill thru rebar.sold these at the tool place--they were VERY expensive.The drills were often used to drill walls or floors that contained rebar.I had seen the solid carbide drill bits-a gunsmith I knew of used them to drill hardened rifle recievers for scope mounts.Another person I knew of used them to drill holes in fiberglass circuit boards-the carbide drills worked well for those jobs.You just can't bear down on them-they will break.You can push harder on the steel bits before they break.
I think its pretty amazing the uses and jobs the carbide tools we have been talking about are used for.I have some literature on the grades and types of carbides-got it from that tool place-just don't know where I put it-that book has been thru 3 moves.I am sure its outdated now.Another thing for the carbides-both the US and Germans used it for armor peircing projectiles.Those shells sure did a good job of holing tanks and concrete pillboxes.The DU projectiles today leave a radioactive residue after peircing a target-that is hazardous to anyone who gets near it or inhales it.The carbide projectiles don't have that hazard.There are thoughts by the ammunition makers to go back to carbide.Some of the "mysterious" illnesses today from the wars could have been caused by the DU residue.