If I can only buy 1 CBN grinding wheel, is 180 grit aggressive enough?

[Patrick Chase]

I don't doubt that you are very skilled in your professional life my friend. But you described your woodworking skills as being "at the infantile babbling level". Please let up on George, a demonstrated Master, and he'll help ALL of us get better at this stuff.
Fred

Fair enough. I would note that *nothing* I've said or claimed in this thread has anything to do with woodworking, though. Abrasives and thermodynamics are completely unrelated to the working of wood...

[Kees Heiden]

I have been searching around, and 1x42 or 2x72 or something similar just doesn't seem to be available overhere. I see these quite a bit, at 100x1220, it is twice as wide as the 2" belt, but a bit shorter then 72". https://www.hbm-machines.com/product...dschuurmachine

Another affordable type of machine are those small bench grinders with a belt attachment on one side. The belt is usually something like 2" x 32". Those are more like toys I guess.

Different types of grinders are usually aimed at the professional market and very expensive.

Maybe it comes down to making one myself. Someday, when I have loads of time available...

[george wilson]

Fair enough. I would note that *nothing* I've said or claimed in this thread has anything to do with woodworking, though. Abrasives and thermodynamics are completely unrelated to the working of wood...

Sorry,wrong again. Abrasives are VERY related to woodworking. There are endless discussions here about what abrasives to use for grinding and sharpening tools for wood working. This has been only one of them . There ought to also be more discussions about available sand papers as well.

I would not consider the heating of metal during grinding to be very deeply involved in thermodynamics. Just another big word (which we all know) to impress,metal tool heating is a simple process experienced by anyone who ever ground a tool. I wonder if Chippendale or Grinlin Gibbons ever thought about thermodynamics.

Kees,I forget how much the Grizzly knife grinding outfit is. But,it certainly is affordable. I don't know about the shipping to Europe! A friend has one,and it hogs off metal just fine. And,even the Burr King grinders have un inclosed belts. I don't know why,though.This is why I prefer the ugly,but very adaptable Wilton Square Wheel belt grinder. You don't want to breathe stray fine metal and abrasive dust. Earlier in my life I could not afford a dust collector,or a paint spray booth. Now I have enough COPD,I get short of breath going to the mail box and back. And,there is no cure.

I beg ALL of you to get a dust collector for your high speed belt grinder. I just have an old Delta,the type that has the motor and impeller mounted above the large drum. I got it used for $150.00. I also have an exhaust fan behind the collector that gets the "fly stuff" which manages to get through the cloth bag. I have a large plastic 12x12" scoop just under where you grind,and a simple 4" spiral wire clear plastic hose going to the collector. Not the World's greatest system,but it works fine. No wood dust is ever allowed to get into the drum. I can see through the clear hose that the largest spray of sparks that I can make are extinguished by the time they get 3 feet down the hose.

Failing this,AT LEAST get an appropriate dust mask. And certainly get a CORRECT dust mask with changeable filters for spraying. I got pyelonephritis in my kidneys back about 1964. I was very active and was spraying lacquer every week or two. Fever of 104. Be careful of messing up your kidneys as well as your lungs. I still have no where to put up a spray booth. But I certainly do wear the mask. I think it was about $40.00. Cheap insurance for your VERY critical internal organs!!

[Brian Holcombe]

I made knives as a hobby in my youth and came to the same conclusion as George, ultimately building myself a variable speed belt grinder. I ground blades out of ATS-34, D2, BG-42 and 440C. When using highly alloyed steels, you find out very quickly what kind of grinding belts do the work quickly.

I don't use it on my woodworking tools because I have not built a dust collection system for it.

[george wilson]

Kees,the Grizzly is $651.00 on Amazon. They say FREE shipping,but obviously that does not apply to the Netherlands!!

The reviews are mostly good. Some report tracking problems. But,they seem to have solved that by buying good belts. I have NEVER had a tracking problem,and use the $2.50 belts I get off of Ebay. My cheap belts never wobble(from being joined together crooked). So,I'm not sure where they are coming from.

Some claim not enough power,but the Grizzly and my Wilton came with a 1 H.P. motor. I find my Wilton plenty powerful enough. But,I am not ham handed. Maybe a beginner is. I made my Wilton variable speed with a 1 1/4 H.P. DC motor and control from Surplus Sales. You will not be able to do this,unfortunately. Having a variable speed motor really helps when putting the finishing touches on a knife,and you don't want to put a dollop in it from a fast moving belt. Take heart,though. None of the knives I have posted were made with a variable speed belt grinder. It was upgraded only lately.

You might want to get a thicker piece of steel to make a more substantial tool rest.

One said the motor gets in the way. That probably refers to grinding very long knives. I think it will be just fine for woodworking tools. I like my 1963 Craftsman bench grinder (but not its cheap looks!) because it has a flat front motor,and did not get in the way when I was grinding things like a draw knife,back when I had nothing else to use.

[Kees Heiden]

Well, it certainly isn't going to happen on the short term, but I have some more metal working projects on my list. Not sure yet what I like more, blacksmithing, filing, handwork, stuff like that or more in the machining direction.

[michael langman]

I find this conversation bringing back to me the age old proverbial quotation, "You can make an engineer out of a machinist, but you cannot make a machinist out of an engineer".

I have been following SMC in the back ground for 5 years or more now, and have only responded if I felt I was able to help someone in some small way. The knowledge on this site has helped me tremendously.

Being a highly skilled tool and die maker, machinery repairman, machinist, and having the to work with some very good engineers, I have learned much in my life.

Using the Machinery's Handbook as a guide, and spending many years on the bench making and building all kinds of tooling, and some dies, and applying them to the manufacturing needed at the time, I can honestly say that, " Not all things in engineering and physics is as straight forward as, coming up with an idea, designing that idea, and applying it to the real world."

All of the most successful mechanical engineers have listened to their toolmakers respectfully, with an open mind, simply because they know that what can be worked out on paper, does not always happen in the real world of making and developing things.

Anybody can have a fine mind and learn how to do an equation or remember Pi = 3.14157...,
but from Experience comes Knowledge.

If I have learned anything this has been the most important.

[michael langman]

I made a mistake in the above statement, From Experience comes Knowledge, what I should have said is that ,"From Experience comes Wisdom."

Knowledge comes from books.
My apologies.

[Pat Barry]

Anybody can have a fine mind and learn how to do an equation or remember Pi = 3.14157...

See, right there is what separates a machinist from us engineers. Us engineers think of Pi as 3.1415926535. We wouldn't round that to 3.14157!

Otherwise I agree with your sentiments

[george wilson]

Why stop at 35,Pi goes on forever.

[Brian Thornock]

I find this discussion fascinating. I am a physicist and see no issue with what George is saying. There are many variables at play with a belt grinder. Just because one does not elaborate them in a discussion does not mean they don't exist. Off the top of my head, other factors at play between belt grinders and wheel grinders are things like grit size, how that grit is distributed and exposed, SFPM, amount of pressure that can be applied to the grinding medium, and on. I build a lot of guitars and many people try to describe all the variables at play in the system. It never works out because there are so many that escape one's notice. Just because they aren't listed does not mean they don't come in to play.

Getting more back to topic, I would like a CBN wheel, but I think that is just the tool acquisition side kicking in. I probably wouldn't get great use out of one, but they just seem so cool!

[Matt Owen]

I find this conversation bringing back to me the age old proverbial quotation, "You can make an engineer out of a machinist, but you cannot make a machinist out of an engineer".

Add this to the list of ridiculous statements. It's a complete over generalization on both sides. Can't we all just get along.

[Niels Cosman]

This is a true statement,not meant to be an insult. Don't take it as such: When you said that your lack of experience did not matter,that was a very extraordinary thing to say. Because,you have to understand,when you are a beginner at something,you do not know how much you do not know. And,the more you learn,the more you will discover that you STILL do not know. The sooner you understand this,the better off you will be when it comes to learning woodworking.

^^^^^^
This is the biggest take away from this thread. This applies to any type of learning, which if done properly, is a lifelong pursuit.

[James Waldron]

{snip}
I also got tired of having to re machine the cast iron platen from grooves getting worn on it. I made a FULLY HARDENED A2 steel platen surface that has a countersunk flat head screw in each corner. Countersunk on both sides so I can turn it over. But,the fully hardened A2 platen has lasted many years by now. MUCH better than running on the soft cast iron platen. Really good grinders have a sheet of carbide,like those for contour grinding windows for cars. But,the carbide has to be custom made. Big bucks probably. A2 works fine. D2 would be even better. But,I used what I had on hand.

I"m a little late here, but maybe it will help someone.
It ain't free, but small amounts of D2 are available as flat plates, square stock and drill rod at onlinemetals*com as are O1, A2, and W1. I've had very good service from them over time.

[Tom M King]

Thanks George and James, I have a little 1x42 that's a decent belt sander with a Baldor motor, but I always hated the folded sheet metal platen. I know what I need to do now.