Vintage norton wheels

Hi everybody,

An older friend of mine gave me a bunch of vintage nos and lightly used surface grinding wheels and smaller ones for a toolpost grinder. Anyway norton wheel threw me off as I could not find documentation on what it does. Ferrous?, non Ferrous? Carbide? Thanks curious. The wheel mounts on a typical 6 12


Danny

37C is a silicon carbide abrasive, preferred for cast iron, also non-ferrous and non-metal (e.g., rubber or plastic), but could be used for most anything.
320 is the grit size, so quite fine for a grinding wheel. You will have to work to keep this wheel dressed, non-clogged, and free-cutting.
J8 is a medium bond and density wheel, maybe one notch on the hard side of medium, nothing to see here, move along.
E is a shellac bond, which is good for cool cutting and fine finishes; good compensation for the 320 grit.

All that "decoding" is totally standard industry numbering system by the way.

Be extra EXTRA careful with shellac bonded wheels, ..........especially old ones, .......unless you are 100% sure about a shellac wheel the only tool you need is a hammer - to smash them.

dgmoto: Danny, do your self a favor and learn to read the wheel designation numbers. Keep in mind that the first pair of numbers are usually a manufactures number and the rest of numbers and letters will tell you what the wheel is made of and will describe the various characteristics such as bond density and and bond hardness and grain size and much other good info. Its been many years since I had to learn them when I first started in a roll grinding shop, but was always handy when I went over to the machine shop side.

JH

Limy Sami said:

Be extra EXTRA careful with shellac bonded wheels, ..........especially old ones, .......unless you are 100% sure about a shellac wheel the only tool you need is a hammer - to smash them.

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I would toss those wheels out.. Old wheels are rotten and dangerous.

Thanks for sharing the information.

There so fine i would guess there for use in the glass grinding industry not ours.

Can be used for grinding carbide like a green wheel. Used to be favored when natural diamonds were common and very expensive. Can give a great finish but may break down (wear away) as much or even more than the carbide they remove. still a good wheel for a very tight corner, putting a tickle edge to an insert or needing a super finish..it was also common to use them for grinding a radius so having space I would likely keep at least one as I am a grinder hand and could use them in a safe way... don't think they ring well if at all so use on a SG or bench grinder better than a TC grinder. Don't get them hot.

Shellac bond lets the grit lose easier than vittrified wheel so runs cool and sharp but you grind with regard for how it breaks down.. like how you go to or come off a step. often down grind then work away from that position/ not run into or toward a step. So you always think of where the wheel is high and low. If you tried to grind a magnetic chuck you might find a few thousandth wear and so a taper in the chuck front to back as the wheel breaks down..*Yes a 320 (fine grit size)wheel would never be used for chuck grinding.

Wheels not having an RPM notation are old and some were for special purpose so it is not a bad idea to break them. That wheel may be a good wheel after broken to be used for wet dressing a diamond wheel.If so it will seem to melt as you rub a wet diamond wheel. Might try it on a slow bench grinder (1800 and 3600) for tickle finish edge to HSS and carbide bits.

High pressure grinding carbide so spin into the edge with wheel going down..then for the last .003 (or so) come from the heal first with still the wheel going down.

As others have noted, old wheels can be dangerous. At the very least, you will want to do a "ring" test, and even then stand well out of the path when spinning them up.

awake said:

As others have noted, old wheels can be dangerous. At the very least, you will want to do a "ring" test, and even then stand well out of the path when spinning them up.

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that is why I said be extra EXTRA careful, ........to my ears a shellac bonded wheel sounds very different to a vitrified bond, ....almost to the point of sounding ''dead'' or just like a cracked vitrified wheel, I know because I got caught out - once (and that was plenty for me )

FWIW Its been a good while,.... BUT IIRC - if you delve in to the uses of various grinding wheel bonds, Shellac wheels have a very limited / specialist application .........so unless you need one of their applications don't use the bloody things

Limy Sami said:

that is why I said be extra EXTRA careful, ........to my ears a shellac bonded wheel sounds very different to a vitrified bond, ....almost to the point of sounding ''dead'' or just like a cracked vitrified wheel, I know because I got caught out - once (and that was plenty for me )

FWIW Its been a good while,.... BUT IIRC - if you delve in to the uses of various grinding wheel bonds, Shellac wheels have a very limited / specialist application .........so unless you need one of their applications don't use the bloody things

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I agree Sami. You only need one wheel to burst on you know it's not recommended.

Regards Tyrone.

I only recently found out that grinding wheels have a recommended use-by date, and it's only a few years!

Not much to go wrong with an AO vitrified wheel or a diamond wheel..
But some old diamond wheels perhaps mid 60s and older would not be sold today because of the binder used in plastics.
Still good to wear a mask for grinding...

Setting around AO vitrified wheel can soak up oil from being out in the air and can become hard to balance. I think wheels should be covered and stacked with a spacer or hung on a peg with a cover and turned occasionally.

Who knows what binders went into a 60 year old shellac bonded wheel. So I would wear a mask at using.

Stacked wheels are likely to tip and fall so chance to crack?

old natural diamond wheels sounded different also, they whispered through the work. Like skimming through cream..They have D listed not MD

As limy said shellac bonded wheel sounds very different

Shellac used as a glue does go brittle with age, I have some shellac based sticks for glueing gemstones to brass dop sticks for faceting. After 20 years, they tend to catch fire instead of melting over an alcohol flame and if you persist in using them, the resulting bond is very weak. If those wheels are bonded with shellac, I would not hesitate to smash them and then bin them. You could also make a Youtube video of them being spun up (from a safe distance) and post the link here .

When I saw the title: vintage Norton wheels, I instantly thought vintage Norton motorcycle!

Tyrone Shoelaces said:

I agree Sami. You only need one wheel to burst on you know it's not recommended.

Regards Tyrone.

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Mine was on a Churchill surface grinder, .the previous guy who'd used it, hadn't ''spun the wheel out'' ...left it running with the coolant turned off, and it had been idle for a day or 2. ......it was a job shop so not in use all the time.

I'd loaded my parts and switched on (the wheel was well up from the table and work) ....... almost before the wheel was up to speed I realised something was wrong, hit the stop button but it was too late.

That pink 10'' (I think) wheel exploded like a shot gun going off, .......the guard stopped the bits going up and round the shop, but a big lump went down on to the work, before shooting out sideways, missing me by inches and bouncing off a lathe back splash guard.

Does wonders for constipation.

PS, When we found the bits, you could see the oil and coolant in some of them on the freshly broken faces.

Shellac polymerises in air, its a slow constant process, so from day one its always setting getting harder, shrinking and getting ever more brittle, same to some degree with the rubber bonded wheels too.

Mine was on a bigger " Churchill " surface grinder Sami. The wheel would be about 15" dia by 2" wide.

I was grinding some large rollers out an old self aligning roller bearing. They'd be about 3" long by 1-3/4" in dia. I'd stood about ten of them on their end to grind them so I could use them as setting blocks. I was grinding away nice and peaceful when all of a sudden there was an almighty BANG and everything stopped. The wheel burst in such a fashion that the loose chunks of wheel wedged inside the wheel guard, jammed the spindle and blew the fuses !

I was really lucky I wasn't hurt but the speed it all went tits up really shook me and left a lasting impression.

Funnily enough I'd be working on another machine near the same surface grinder when the operator was doing exactly the same job. I heard a bang and I looked around to see one of the rollers flying through the air at head height down the shop. The machine pointed down the passage way and the roller went about 30 yards before landing !

We turned the grinder around after that so it pointed at a wall.

I must have been a slow learner because a year or two later I did exactly the same thing. I found out later that the rollers were slightly convex on the ends !

Regards Tyrone.

Limy Sami said:

Mine was on a Churchill surface grinder, .the previous guy who'd used it, hadn't ''spun the wheel out'' ...left it running with the coolant turned off, and it had been idle for a day or 2. ......it was a job shop so not in use all the time.

I'd loaded my parts and switched on (the wheel was well up from the table and work) ....... almost before the wheel was up to speed I realised something was wrong, hit the stop button but it was too late.

That pink 10'' (I think) wheel exploded like a shot gun going off, .......the guard stopped the bits going up and round the shop, but a big lump went down on to the work, before shooting out sideways, missing me by inches and bouncing off a lathe back splash guard.

Does wonders for constipation.

PS, When we found the bits, you could see the oil and coolant in some of them on the freshly broken faces.

Click to expand...

OT:
Couple of years ago local millwright died when big pedestal grinder wheel exploded and hit him in the chest. After that they decided to get rid of bigger pedestal grinders and replace them with belt grinders. IMO much better solution for shop use where every dickhead has access to bench grinder..

Tyrone Shoelaces said:

Mine was on a bigger " Churchill " surface grinder Sami. The wheel would be about 15" dia by 2" wide.

I was grinding some large rollers out an old self aligning roller bearing. They'd be about 3" long by 1-3/4" in dia. I'd stood about ten of them on their end to grind them so I could use them as setting blocks. I was grinding away nice and peaceful when all of a sudden there was an almighty BANG and everything stopped. The wheel burst in such a fashion that the loose chunks of wheel wedged inside the wheel guard, jammed the spindle and blew the fuses !

I was really lucky I wasn't hurt but the speed it all went tits up really shook me and left a lasting impression.

Funnily enough I'd be working on another machine near the same surface grinder when the operator was doing exactly the same job. I heard a bang and I looked around to see one of the rollers flying through the air at head height down the shop. The machine pointed down the passage way and the roller went about 30 yards before landing !

We turned the grinder around after that so it pointed at a wall.

I must have been a slow learner because a year or two later I did exactly the same thing. I found out later that the rollers were slightly convex on the ends !

Regards Tyrone.

Click to expand...

Found which Churchill that nearly had me - it was an OSB and if memory serves ''must'' have been the 60'' table (going by the number of parts we could get on in one go, ..anyway a Ref http://www.lathes.co.uk/churchill-surface/