Grinding by circular saw?

Go pick up an angle grinder some earmuffs and a proper side loading grinding wheel. Clamp your blade and grind away. While browsing for proper side loading disks I found a picture of a man who had a broken disk go right into his face under his eye. So use proper equipment.
 
Maybe Kevin needed another cup of coffee, he was a bit short with you ;)

But I totally understand where he and others are coming from. I've also felt his same frustrations many times on the forums.

A new maker asks for help/advice, experienced makers then give them advice, then the new maker says, "Well, I'm going to keep doing it my way anyway, no matter what you say."

This is a slap in the face, and makes ME think, "Well, what the f did you ask for then!?!?!"

On your specific question Vassilli: First of all, I think many people thought you were talking about a portable circular saw (Skil saw). Which would be even more dangerous.

The miter saw you're using is, quite simply, NOT made for the type of work you're asking it to do.

There are a myriad of things that could go wrong with this set-up. One very clear one is the diamond blade grabbing/getting pinched, and throwing the blade at you. Even if you have the blade heavily fixtured (which I doubt) you're at risk for this.

If you're hell bent on cutting in this fashion you would be much better off to get a 14" abrasive cut-off saw, and use it's fence/vise set at an angle to do STRAIGHT cuts on the steel.

Even better, buy a small metal cutting bandsaw with a good bi-metal blade, it will cut VG10, trust me, I know!

Even better YET! Buy some good ceramic belts in 50-60X and grind your profile, it is the fastest method.

:)
 
Rpm rating of blade would be the major factor. Even the metal abrasive blade you are talkng about is not ment to side load. You must be extremely careful of this. I have used a miter saw just like that to cut thin aluminium. It works fine but once again entreme care must be taken. I would use a good system to secure the blank. The saw you are using is a motor and we all use motors in various ways to spin dangerous equipment. If you don't over rev the blade, side load it, and firmly secure your work oiece I see nothing more dangerous than using a belt ginder. An abrasive chop saw is not any better constructed than a good miter saw, but it does have a system to secure the work piece. and would probly be cheaper than your miter saw. I think you will find that it is slow going. Does the diamond wheel normally use a water cooling system and if so you would need to provide a system to accomplish this.
 
Vissali. You have taken some slack in this thread I see and your probably so pissed off and going to do it anyway:

Looking from a purely practical point of view, those diamond discs are made for particulate ceramics and concrete and are not optimal for the more homogenous metals. Also at high speeds the metal on metal will generate high temps and the two surface may seize against each other causing the blade to 'bite', with obvious consequences. If using a disc with an uninterrupted periphery I would say the odds of the disc fragmenting would be small, but if you were using the segemented type, this risk would be significant. I originally thought you were referring to using a diamond disc in a table saw and thought that provided this was done carefully with no side pressure it should be 'safe'. This would be a much more 'rigid' arrangement and hence safer. The cut off saw you show is a more flimsy apparatus and hence would be quite a lot more dangerous. Im not really sure would could be practically achieved apart from cutting out a blank with that set-up.

From the safety point of view... remember no knife is worth your life.

Sanding belts have a misfortune of having a very thin layer of abrasive and the longevity of the belt relies immensely on how the abrassive is bonded to the backing, and the characteristics of that same backing. Very hard steels will tend to wear belts quickly. Grinding discs and wheels on the other hand will happily handle harder steel without as much ill effect, and because these abrasives have a 'self-conditioning' nature, you will have a lot more success with grinding.

Whatever you choose to do, I hope you come right, but just be safe.
 
Well, I just read this again and realize that I totally misunderstood you. I thought you were just rough cutting the profile of the blade. Trying to actually grind the bevels down with this set-up is a totally different story. :o
 
Nozh,
We may all have misunderstood what you were doing. I,too ,thought you were using a table saw to do shaping. That could be disastrous. Using a miter saw for shaping a blade is also not advisable. Let's look at it this way. Have you ever seen any metal shaping tool set up like that? No? There is a good reason why - It is not safe !!! Using any tool for a job it is not intended for is foolish, and can be harmful to both the tool and you. There are all sorts of things like torque load, edge speed, side load, blade flex,motor duty cycle, ..... to take into account. Your profile doesn't give any info about you, so we don't know if you are a 16 year old fiddling in dads wood shop, or an engineer who designs for Boeing. The folks who answer questions here have to err on the safer side when giving advice blind (which is a good reason to fill out your profile).

We sometimes seem glib and flippant when answering questions like yours. Sometimes it is because it is so obvious to us that it won't be a good idea. Other times it is in the way the question was asked. And sometimes we can be butt holes. But no one here (well not most of us,anyway) is giving you any advice that we wouldn't give our son or best friend.
Stacy
 
I understand that this is unusual approach, but CPM 10V is quite unusual steel. I spend three belts to grind it just a little bit - just barely scratch it (it is cheap generic belt but I did grinding with same before with much better success on ATS34 and A2)! Again this stuff is almost ceramic due to enormous content of vanadium carbides and so this why not to many making knives out of it (I may understand why now when I tried it myself) and this is also why I am want to have this knife too bad.

I try diamond disk - does not work. wear out pretty fast. So I came back to cutoff disks. Norton metal cut off disks 10".

Thanks to your posts I understand the danger of this and so, disassemble magnetic knife holder and make solid magnetic base to hold knife very tight while I stay as far as possible out of potential hit zone by pieces of disk. It is on the extended arm distance from my face. But I am moving saw slowly only down and avoiding any side loads.

I am very thankful to you guys who gave me good advice. I am very upset with jokes like - you going to die soon, because you are stupid. This is not what I am looking for here and I am pretty sensitive to THIS kind of "humor" - sorry if it make some of you standing aside uncomfortable. What the point to say this? Just to feel smart himself, calling others stupid? We are not in 5th grade, aren't we?

With all precautions I did some grinding, which is again very delicate, gentle cuts same as cut-of, but unfinished.

I'll try to post some pictures later...

Thanks, Vassili.

I am not knifemaker but this is my work:

knife-83-015.jpg


knife77-16.jpg


knife84-09.jpg
 
What kind of belts are you using? Quality belts save money because, although they cost more, they outlast cheap ones by a LOT.
 
Vassali
For "not a knifemaker" those are some really awesome looking knives! Love the chunkiness of that second one. Great work
 
Read carefully:

I wasn't making a joke.

What part of my statement don't you understand?

"Seriously, take up another hobby. Stop using power tools or get some serious training. Your idea is one of the most dangerous and – how can I say this nicely? – incredibly stupid methods or working steel I have ever heard – even in the Internet!"

You know nothing of working with power tools and even your statements about the steel you're working are totally false.

What you're trying to do is a good way to get yourself seriously injured – crippled – or killed. Is that understandable to you? Does that sound like a joke?

Why do you think everyone else here trying to help you has said the same thing??

But hey, it's your your decision. Do what you want.

I just hope that anyone else reading this and thinking for even one instant that they might try anything remotely similiar will realize that it is incredibly dangerous and totally unnecessary to accomplish what you're trying to do, which is put a bevel on blade. Anyone in a metal working shop who even suggested something like that would be fired on the spot.

Now jump back in and have your last word. I'm out of this.
 
First,
CPM10V is not ceramic and the amount of vanadium is nominally 10%. It does not get extremely hard until it is austenitized and quenched. If it is annealed stock, it should grind just fine with good ceramic and CZ belts. Yes it is tougher to grind than ATS-34, but it is a better steel for many jobs.

Second - and this is important,
One big reason there is so much peer review on this site is that one false statement or bad procedure can lead to many people passing that info along as a tried and true fact. The implication is that all knifemakers do it, or at least the really good ones do. Statements like, "There was a guy in XXX that used to do that all the time, and he made good knives." or " I have always done XYZ and none of my customers ever complained." Neither of these statements prove any technique, but may be passed on as proof . There is a maker on this forum who gives a lot of advice, and has only made two or three so-so knives - ever. He usually says, "What I do is......" Someone who is seeking to learn by reading this forum may see that and say, " That is good advice because Mr.X says he did it." When reading Internet information always consider:
All advice is not golden.
All ideas are not necessarily good ones.
All techniques that give a certain result are not necessarily safe or good.
Thousands of posts don't make you an expert.
BUT:
Advice that is seconded and backed up by many makers is usually sound.
Techniques and procedures that have been used for years and are regularly taught in books and schools are usually good ways to learn.
Learning by experience is a good teacher, but safety should be your primary concern, when trying new things.
Listen to your inner voice, If it doesn't sound right, stop and re-think your plans.

We all want you and every new maker to have a fulfilling and safe hobby. Using tools to do what they aren't made for, and giving steel properties that it doesn't have won't be the best path.

I hope I haven't offended you, because I really do care for your well being.
Stacy
 
Of course this is experiment and I came here to see thoughts and advises about it. I have some idea and like to discuss it with someone who may done this already or did similar things and how dangerous is it.

OK - the pictures I made yesterday:

misc030.jpg


misc031.jpg


misc034.jpg


misc035.jpg


Thanks, Vassili.
 
I can achieve the exact same result (except for I'd manage to do the ENTIRE blade bevel) in under 25 minutes using a 36 or 50 grit belt on my grinder, which can also be used for many other tasks in knifemaking... I cannot say the same for a cheap wood miter saw.

I can do it freehand, and I can follow an unusual curve in the blade if I want to, and I can do it all repeatably and safely.

Unless the steel is hardened, there shouldn't be any problem grinding it... it may take slightly longer than a simpler steel, but not enough to consider mentioning.


If Mr. Wilkins seems confrontational in this instance, it's because he DOES have the experience to back it up!


Because someone says that they've done it a certain way for 20 years does NOT mean that they've done it right (or safely) for 20 years!

Personally, I think I'd rather see you around 20 years from now, rather than reinforce your dangerous position on this matter!
 
MrPurple said:
I can achieve the exact same result (except for I'd manage to do the ENTIRE blade bevel) in under 25 minutes using a 36 or 50 grit belt on my grinder, which can also be used for many other tasks in knifemaking... I cannot say the same for a cheap wood miter saw.

I can do it freehand, and I can follow an unusual curve in the blade if I want to, and I can do it all repeatably and safely.

Unless the steel is hardened, there shouldn't be any problem grinding it... it may take slightly longer than a simpler steel, but not enough to consider mentioning.


If Mr. Wilkins seems confrontational in this instance, it's because he DOES have the experience to back it up!


Because someone says that they've done it a certain way for 20 years does NOT mean that they've done it right (or safely) for 20 years!

Personally, I think I'd rather see you around 20 years from now, rather than reinforce your dangerous position on this matter!
Click to expand...

How many CPM 10V knives you made and how long does it usually take for you to? Again I may have to spend more time but I made few blades also with different steel. In theory it should not be any problem, but did you tried it yourself?

Thanks, Vassili.
 
If your idea of a magnetic chuck is a bunch of loose magnets and a lego, I SERIOUSLY worry about your safety and well being.

You seem to be elevating CPM10v on a pedestal and attributing it magical properties... it doesnt have any, it's just another steel, treat it exactly like you would any other steel for grinding. Get rid of generica AO belts, buy some good 3M or klingspor etc ceramic belts and grind it on a real grinder.

You're going to get yourself or someone else killed or seriously injured.
 
Nozh, take the following as internet advice, and worth every cent of what you paid for it. I think that with your setup the biggest danger is the blade of the saw trying to pick up the front edge of your blade and flipping it. This can chew up your blank in some odd places and also mess up fingers or anything near the blank. If the blank happened to get caught just right it could break your abrasive disk and throw pieces. If you had the blade clamped securely, these dangers would be lessened. It seems though that the time you spent clamping, sawing, reclamping, would be pretty inefficient. YMMV. If you understand what you are doing, then you can make your own informed decisions. If you don't, then you would be better off listening to others. I really like certain things you did with those knives. Be safe.
 
Justin.Mercier said:
You seem to be elevating CPM10v on a pedestal and attributing it magical properties... it doesnt have any, it's just another steel, treat it exactly like you would any other steel for grinding.
Click to expand...

Well and how many knives out of this another steel you made?

Thanks, Vassili.
 
Any Cal. said:
Nozh, take the following as internet advice, and worth every cent of what you paid for it. I think that with your setup the biggest danger is the blade of the saw trying to pick up the front edge of your blade and flipping it. This can chew up your blank in some odd places and also mess up fingers or anything near the blank. If the blank happened to get caught just right it could break your abrasive disk and throw pieces. If you had the blade clamped securely, these dangers would be lessened. It seems though that the time you spent clamping, sawing, reclamping, would be pretty inefficient. YMMV. If you understand what you are doing, then you can make your own informed decisions. If you don't, then you would be better off listening to others. I really like certain things you did with those knives. Be safe.
Click to expand...

Those magnets are quite strong, I have steel bars screwed to the saw base and magnets on it and blank on top? I can not gust lift it up, I need to slide it to the side and I can pick it. Disc did not penetrate deep 2mm or something and again this is cut off disc not a saw. I move saw very gentle and do not keep it on blank more then few seconds with lightest pressure.

I found that disc got some steel dust and stop biting - I gently clean this dirt with file so it start cutting again.

Efficiency is not my concern, I can spend weeks on this, no problem. However it is more matter of days in this case.

I listen to others - like to yourself. But it seems nobody here claim that they work with this steel so far. I know only Phill Wisson and L.R.Harner working with it.

Thanks, Vassili.
 
If you are looking for someone who has used this steel, I have. I use CPM154, CPM S30V, CPM S90V,CPM M4, and have made two blades from CPM10V. CPM S90V has the virtually same vanadium as CPM10Vplus several times the chromium and molybdenum. CPM10V grinds well with Cubitron, Blaze,CZ, and ceramic belts. The hollow grind you are making can be done freehand on a 10" contact wheel in 10 or 20 minutes at the longest. Sanding to a finer grit will be much easier since there won't be all those grinding grooves to deal with (and the same wheel is used, so the grind channel is already established).
Stacy
 
You must log in or register to reply here.
Back
Top