My new grinding setup

Re: My new grinding setup

Paul Leuba

Mark, that’s very innovative. A question: in the second picture there appears to be a slight radius on the ground edge. Is that on purpose, or perhaps, the result of a wide angle lens?

Paul in Hunt Valley, MD

Re: My new grinding setup

Mark Nowicki

Thanks, but it is not my innovation or idea. I read about a similar setup in an old woodworking book.

The camber is what I wanted to achieve.

Re: My new grinding setup  *LINK*

William Duffield

Your jig gave me an idea. For those of us who are turners, we probably have a Wolverine jig with the attachment for roughing gouges. Mark's length of T-track, 2 T-bolts and 2 knobs could easily adapt the Wolverine for this plane blade cambering setup. In the picture, just replace the roughing gouge with the top end of Mark's jig.

The picture is from Woodcraft's offer for the Wolverine jig.

https://www.woodcraft.com/products/oneway-wolverine-grinding-jig

Re: My new grinding setup

walta

Mark it seems likely you and or other that may not understand how very very dangerous your improvised grinder is as shown.



Your grinding stone is totally on guarded. The stone wheel is very venerable if anything should happen to bump into the side of the stone it is likely to get a hair line crack, the next time the wheel comes up to speed large parts of the wheel are very likely to go flying in every direction. Should even a small part of the wheel find your head your survival seems unlikely.

Walta

Grinder Safety – Grinder Safety Do’s

Always handle and store wheels in a careful manner

Visually inspect all the wheels before mounting for possible damage

Make sure operating speed of machine does not exceed speed marked on wheel, its blotter or container

Check mounting flanges for equal size, relieved as required and correct diameter

Use mounting blotters when supplied with wheels

Be sure work rest is properly adjusted on bench pedestal and floor stand grinders

Always use safety guard that covers a minimum of one-half the grinding wheel

Allow newly mounted wheels to run at operating speed, with guard in place, for at least one minute before grinding

Always wear safety glasses or some type of approved eye protection while grinding

Turn off coolant before stopping wheel to avoid creating an out-of-balance condition

Grind Don’ts

Don’t use a wheel that has been dropped or appears to have been abused

Don’t force a wheel onto a machine or alter the size of the mounting hole – If a wheel won’t fit the machine, get one that will

Don’t ever exceed maximum operating speed established for the wheel

Don’t use mounting flanges on which the bearing surfaces are not clean, flat And smooth

Don’t tighten the mounting nut excessively

Don’t grind on the side of conventional, straight or Type 1 wheels

Don’t start the machine until the safety guard is properly and securely In place

Don’t jam work into the wheel

Don’t stand directly In front of a grinding wheel whenever a grinder is started

Don’t grind material for which the wheel Is not designed

Re: My new grinding setup

Mark Nowicki

You are right on all counts.

As soon as I settle on the final layout I will put together a guard.

Re: My new grinding setup

Derek Cohen (in Perth, Australia)

Better still, no guard is required with a CBN wheel. Once you get one of these you will wonder how you managed without it.

Regards from Perth

Derek

Re: My new grinding setup

Mark Nowicki

Maybe, but my current mantra when it comes to woodworking is:

"Thou shall spend no money on tools."

Re: My new grinding setup

Derek Cohen (in Perth, Australia)

Mark, consider a matra ..

"Thou shall spend no time on inefficient methodology."

Regards from Perth

Derek

Ouch! Touché.

little room for improvement

Bill Tindall, E.Tn.

The only benefit one of these wheels could have to my applications is these wheels don't shed particles. I have had to isolate my grinding from the rest of the woodworking because of particle shedding. Beyond this advantage there aren't any others for me that I recognize, even if the switch was cost-free.

Re: little room for improvement

Derek Cohen (in Perth, Australia)

Bill, not only does CBN not shed particles, but it does not wear, and this means that grinding setting remain the same. Less time setting up, no maintenance, no wear. More predictable. What's not to like?

Regards from Perth

Derek

Re: little room for improvement

Mark Nowicki

Recommended size and grit, cast steel or cast aluminum?

Edit: never mind the (deleted) link.

CBN criteria

Derek Cohen (in Perth, Australia)

Mark, here it is anyway ...

Either 8” or 6” wheels.

180 grit is a great all rounder for existing bevels on plane blades and bench chisels.

80 grit is more grinding/creating new bevels.

Lathe chisels sharpen from 300 grit upwards.

I prefer the steel wheels, as they make better heat sinks (grind cooler), but full alloy is also excellent.

Wheels are also available for Tormek grinders.

Regards from Perth

Derek

Re: CBN criteria

John Jardin

Derek is right as usual.

CBN wheels are now the equivalent of using a smart phone. (my sister still uses a flip phone)

I took delivery last week of my new 1hp slow speed grinder with 180/600 grit CBN wheels. This new system compliments using my Tormek.

Is a mantra the same as a wife? 

Re: CBN criteria

Bill Tindall, E.Tn.

I would think the better conductivity of aluminum would make an aluminum wheel a better heat sink.

Re: little room for improvement

Bill Tindall, E.Tn.

Something like 10 years ago I bought a soft pink 120 grit wheel for hollow grinding. It has been used for whatever tool sharpening I do as well as the occasional class I teach. It cost about $20. I will never use it up.

Were I to replace it, it would be with an 80 grit wheel, soft pink. When I was learning to hollow grind the slowness of the 120 grit was an advantage. Now I can handle the faster removal rate of a coarser grit. The diamond step that follows doesn't care if it is dealing with 120 or 80 grit scratches, again something I did not know at the time.

particles and wear

John K Jordan

>>>Bill, not only does CBN not shed particles, but it does not wear, and this means that grinding setting remain the same. Less time setting up, no maintenance, no wear. More predictable. What's not to like?

If by "it does not wear" you mean the wheel does not change size appreciably by with use, that is one of my favorite things about the CBN. Set a jig once and it won't need to be changed months later.

If by "CBN [does] not shed particles" you mean it doesn't continually throw off a heavy spray of abrasive particles with use like a conventional wheel, I agree.

I'm not trying to be argumentative but CBN wheels do shed particles and do wear, but do both in a different sense. I think this and a few other things are important for every CBN user to know.

PARTICLE WEAR: The wear, not in wheel size but in particle wear, can be significant depending on the use. Robo Reed reported his experience with wearing out wheels. IIRC he said one lasts him about a year with heavy use. Mine have lasted much longer. Much depends on how often and how heavy of sharpening is done.

The wear is slow and doesn't affect the grind until it finally gets too far gone.

When a CBN wheel is new a microscopic examination shows many sharp corners and particles that stick up higher then the mean surface. I could even feel these "high" particles with my finger. This is certainly from the method of application and bonding to the metal surface. A new wheel removes metal quite quickly at first due to those higher particles, behaving much like a much coarser wheel. After a "break in" period the wheel settles down and performs more uniformly for the long haul until it is slowly and finally degraded enough to notice. Reed mentioned in an old article the break-in period might take a month.

Example: When I replaced a heavily used 350 grit wheel with a 600 grit wheel at first it acted much like the 350, both in the rate of metal removal and the scratches on the tool surface. After a few weeks of use it settled down and started acting more like I expected. This is presumably after the high particles were broken away. During this process, those particles have to go somewhere. I suspect some are thrown into the air.

STEEL DUST: Another thing a CBN wheel (and probably any grinding wheel) puts into the air: steel dust. This dust is so fine it is suspended in the air. I constantly find coatings of fine black steel dust adhered to strong magnets across the shop. Those I monitor are at least 10' away and near the top of the backside of my bandsaw (the side facing away from the sharpening station) high off the ground. The particles are especially obvious if I place a piece of white paper over the magnet. Try it sometime. The stronger magnets pick up more steel dust - those I notice first are 1/2" super magnet cubes but other smaller and weaker magnets, even further away in the shop also accumulate this steel dust coating.

If I grind with the CBN in a darkened room with a bright light I can easily see the extremely fine steel dust floating through the air. All this is a good reason to wear a respirator. Steel dust might not be good for your lungs. (Of course, maybe some researcher will discover it oxidizes in the lungs and adds iron to the blood, who know!

FIRE HAZARD: Note that some people use strong magnets just under or behind the CBN wheel to try too contain the steel dust. If using this, clean the dust frequently from the magnet. I once let a fairly large fuzz ball of dust accumulate and was surprised one day to find a red-orange glow of burning steel inside. This was apparently started by a tiny spark from a grinding operation. I work on stainless steel tables this MIGHT not have burned my shop down if I hadn't noticed it.

PHYSICAL DAMAGE TO WHEEL: Out of carelessness I once presented a gouge to the rotating surface of a fine CBN wheel. It caught with a bang like a catch on a lathe and gouged a small chunk out of the wheel. This scratched through the thin layer of CBN on the surface and gouged the aluminum wheel. Until I dressed it down this spot made a "click" on every rotation. After dressing, the wheel still worked the same. The big advantage of impact and other damage to a CBN wheel compared to a conventional wheel is damage to a conventional wheel can cause it to shatter and throw chunks at one's face.

WHAT I USE: As for the CBN wheels and the grits, after experimenting with a number of grits I settled on this, perhaps a bit overkill for some but works for me. All are sollid aluminum wheels. All have square corners on their edges instead of the 1/4" radius is mostly useful to a limited audience. All have 1" of grit down both sides for special grinding operations.

8" CBN wheels:

60 grit for shaping tools tools such as NRS, new grinds on skews and such

600 grit for sharpening all scrapers, skews, and some bowl gouges

10" CBN wheel on a very slow-speed Tormek sharpener:

1200 grit, mostly for sharpening my spindle gouges, chisels, for repairing carving tools. I don't use it for plane irons since I use a plane rarely.

(I first had a 600 grit Tormek wheel but found it too coarse to suit me)

BTW, for general metal work I also have three other bench grinders with various convention wheels, wire brushes, and metal polish wheels. It is not recommend to grind non-hardened steel with CBN.

Your mileage may vary in using CBN to sharpen tools. I rarely turn green wood and I don't power sand. I like to turn very hard, fine-grained wood, often in spindle orientation. The 1200 grit gives a good surface and the Tormek leather stropping wheel quickly give a razor-sharp polished edge which give me the cut that makes me happy.

An old picture from my shop, a bit different setup now.

JKJ

NM:My Mantra for over 40 years. LOL!

Re:  particles and wear

John Jardin

John, Thank you for the great education that your posts share to us.

Re:  particles and wear

Wiley Horne

John,

I did find your description and photo of the different CBN wheels and their uses of strong interest. Sometimes, a person does such a fine job, it doesn’t seem like there’s anything left go say .

I would add one personal note: I use a 200g CBN wheel on a Tormek, primarily for grinding plane blades and chisels. Honing is then done on stones. I recently replaced the large leather wheel—heavily loaded with Tormek paste—with a new leather wheel left bare. After honing on stones, I apply a final buff using the bare leather wheel—wonderful results.

Your post is great.

Wiley

Re: My new grinding setup

walta

In my opinion no homemade guard is up to the job of containing a failed grinding wheel and I certainly would not bet my life on one.

Even the stamped tin one give me pause and I am sure they have been tested while the homemade one is just a wild guess.

I would not put my life at risk to save $160 but it is your money and life value it as you see fit.

Walta

Re:  particles and wear

John K Jordan

Looks like I didn't proofread well.

"try too contain the steel dust" and others. Oh well!

Duly noted.