👍👍

Thanks for watching!

Thanks a lot!

Скажем спасибо массовому производству!

This not a saw @$$ hole , these are diamond blades and expensive because have diamond

⁠​⁠@@yashar4086Bort is not nearly as expensive as gem grade diamonds. The process is what makes the expense.

@@yashar4086 lol bro these are definitely saw blades. please relax.

When an ignorant person does not want to understand something, he takes the path of being a donkey

Thanks for watching! ;)

Thank you for enjoying my video as always ;)

Mohs hardness 9 grinding wheel (aluminum oxide / corundum) against Mohs hardness 10 material - diamond. They don't want to use a diamond grinding wheel because it will cut the diamonds. They want the diamonds to protrude from the carrier matrix - which is some sort of carbide (e.g. tungsten carbide). The oven process used to make the carbide is called sintering.

@@fredinit Thank you! This is really interesting stuff. I know the old saying, cut diamond with diamonds, but as you know that is not the only consideration. I’d like to know more about the diamond powder that is referenced in the video. I figure its composition is a fraction actual diamond and something else like an oxide that behaves like a flux. For sintering as you describe. I’d also like to know how they crush the diamonds to the size they prefer for this powder. Neat stuff!

China can manufacture to any standard. You just don't want to pay for it.

@@ShainAndrews No, I don't want to send my money to an aggressive regime that pays no heed to international law.

Just automate these simple tasks like painting, etc

시청해주셔서 감사합니다 :)

I was going to say the same thing. 😊

I think he'd appreciate the feedback.

That difference may not exist in Korean, in many languages it's just different types of soldering for everything, you just specify wich type of solder, like TIG soldering, brass soldering, tin soldering, laser soldering, friction soldering and so on.

That may be so… but the English subtitles end up being incorrect. For anyone not hip to the lingo, brazing (or hard soldering) is the act of heating two objects, then using a filler material to join them (think: glue). Welding is the act of bringing one or more objects to the point of being molten then with or without filler they are joined by the fusion of those materials.

Not everyone has English as their first language.

Thanks for watching!

Thanks for watching!

That "diamond powder" looks more like a mixture of diamond powder and the metal (brass? bronze?) fillings, and this metal is going to hold it together, i.e. act as a matrix for diamond grit. It's the same as with "carbide tips" (saw tips or cutting inserts) - tungsten carbide (WC) or titanium carbide (TiC) are too brittle by themselves (and probably next to impossible to form into some definite shape alone), so they are always used within more elastic matrix - typically cobalt and vanadium (AFAIR).

That "diamond powder" looks more like a mixture of diamond powder and the metal (brass? bronze?) fillings, and this metal is going to hold it together, i.e. act as a matrix for diamond grit. It's the same as with "carbide tips" (saw tips or cutting inserts) - tungsten carbide (WC) or titanium carbide (TiC) are too brittle by themselves (and probably next to impossible to form into some definite shape alone), so they are always used within more elastic matrix - typically cobalt and vanadium (AFAIR), hence different classes of inserts, dedicated to various materials (hard/ soft) and types of cut (continuous or interrupted). And then there are ceramic inserts, polycrystalline diamond inserts and cubic boron nitride inserts, but they are totally different animals (and pricey as hell too). Abrasive discs for bench grinders use (typically) a ceramic matrix, while these for angle grinders are phenol-resin bonded (hence the funny smell when cutting steel with them). Also, this "baking" is probably called "sintering" in the trade. In a nutshell, you just heat the mixture to the "below melting point" temperature. PS: At 13:43 you can see individual diamond grains - these tiny black "pimples" are diamonds, all the rest is just a matrix holding them in place. When an individual diamond piece gets too dull, the forces acting on it (while cutting whatever it has to be cut) become stronger than adhesion forces holding it in the matrix, and the grain falls off, and the matrix quickly wears off until new piece of diamond "comes out" - and so da capo al fine. However, when the material being cut is too soft there may be to little force to actually force that blunted grain out (a normal occurrence when drilling holes in glass panes), and that's why the manual calls, in such cases, to run the discs through hard material for a while to "resharpen it". Kinda counter-intuitive, but when you know "how it works" it makes sense. (In case of glass grinding core drills, the drill is pushed into a block of aluminium oxide, aka corundum, normally used as mild abrasive stone for hard steels, like HSS.)

@@MrKotBonifacy wow what a great explanation thank you. I have seen WC inserts being made and knew they had a binder hence my question about this "diamond powder", much appreciated

@@campbellmorrison8540 Be my guest : ) Also, I just noticed I omitted one sentence in my previous comment - nothing critical, I just forgot to add "and when the material of matrix/ binder is heated (during sintering) individual pieces of it "glue" themselves with their neighbours, akin to what happens during so-called forge welding". BTW, that "self-sharpening mechanism" works for all grinding materials - ceramic discs for bench/ die grinders and angle grinder ones as well. And, oh, "there's one more thing" ;-) I answered few other questions "like yours" here (there were more than few people asking the "about the same" but the author never answered these so I chimed in, but kinda lost track of what to whom I typed), so anyway: _"What sort of grinding wheel do you use for grinding diamonds?"_ Fro "grinding diamonds as such" a paste of diamond powder and oil (vegetable one?) is used - this is how they make gemstones of rough diamonds, but in this case here you don't really "grind diamonds" but the matrix material and a little bit of the outer part of that steel discs - for which a regular silicon carbide (SiC) ceramic bonded grinding discs are used. And they sorta-kinda manage to do just that, HOWEVER, whenever a diamond piece embedded in the matrix meets that SiC disc it just rips it apart, like a steel ripper rips soil - hence the insane amount of dust produced in the process (it's all SiC grit ripped off the grinding disc) and the rate these discs are used up in the process. But then you have to smooth and flatten the edges of these diamond discs, and SiC-ceramic discs are relatively cheap, so this is how they do it - and then there's no way around it anyway. Even if they tried to use a diamond abrasive wheels (i.e. discs with a thick layer of diamond grit embedded in brass or bronze, or in resin or rubber, which are used in machines for grinding and polishing glass pane edges and for fine-grinding of carbide tools, like tipped saws) these discs would probably get clogged with all that "non-diamond" material. Can't vouch for it, never saw it happening, but I've heard from someone running a carbide tool sharpening shop that whenever a carbide tipped circular saw requires "deep" grinding he uses regular corundum discs to remove some of the steel behind carbide tips because steel tends to clog diamond discs (in the same fashion like aluminium, which clogs regular cutting and grinding discs). And then these diamond discs I just mentioned aren't exactly cheap either, so I guess that "SiC-ceramic discs" option still comes out as the cheapest one. But this is just my educated guess, so don't take it as any Holy Revelation of sort ;-)

Diamond is not sharp.

@@ShainAndrews not with that kind of attitude

Same method... roughly. Pseudo sintering with the addition of epoxy bonding agents.

Thanks:)

That "whole lotta dust" is actually MOSTLY (like 99.9% I'd say) silicon carbide (SiC) dust from all these grinding stones used to smooth/ flatten the diamond grit holding matrix. While the matrix is pretty soft (bronze or brass, I reckon - maybe aluminium bronze or silicon bronze) the diamond grit wreaks havoc on much softer silicone carbide, hence the insane amount of dust - but then again nearly all of it is evacuated before it can "float around" and settle on the machinery. But some of it probably does get airborne, dunno for sure.

Looks like regular silicon carbide (SiC) grinding "stone". And it isn't grinding "diamond" edge "as such" but mostly metal - i.e. steel discs and the brass (probably brass) matrix (that darker, thicker stuff around the circumference of these discs) which holds diamond grit, so "yes, we can". But still, the diamond grit "does its job too", and it grinds down much softer SiC disc like crazy, hence this insane amount of dust.

Она в будущей пятилетке...

Дружище, технологии в Северной Корее гораздо современнее, чем то, что ты увидел здесь в этом видео.

PROBABLY because of how ridges on cutting edge are shaped - they are meant to make cutting more efficient and (probably) make the disc last longer.

For those disks... I see no reason for them to be directional. Probably an artifact left over from other image files used on the laser that were modified for these disks.

Maybe if you weren't so poor you could buy more expensive hardware.

The tiny black dots are the diamonds. They're embedded in a metal matrix.