carbide micro fracturing is a bitch...so is titanium (inconel isn't too fabulous either). The ONLY cool thing I like is the magnesium-esque fire/burning properties
@@jasonaldenhaley1 I've never set any on fire -- even grinding it a little. A machinist friend said someone at his shop set one on fire with a milling machine and it was just impossible to put out. Burned up a lot of expensive equipment before it burnt itself out. I do know that grinding in on a regular home shop type grinding wheel produces the longest and brightest white sparks I've ever seen.
@@luke_skywanker7643 I'd purposely take a super light cut for that 'S.O.S.' pad chip ball and then she'd light up SUN-BRIGHT and no, not puttin that out. I couldn't imagine surviving a plane crash just to...omg, don't even wanna think of that stuff burning a person!!! Million degree burns right there... hopefully get out AS SOON AS POSSIBLE!!
@@jasonaldenhaley1 True. Magnesium and aluminum are pretty bright and hot when they catch fire -- but nothing like titanium. Titanium is also supposed to be "water reactive" when it gets to about 1,300f. It breaks down the water, absorbing the oxygen and releasing the hydrogen, causing an explosion.
I can’t believe that such a large milling machine like that doesn’t have a coolant system to keep the cutting inserts from getting very hot and apparently wearing out in short time period!
@@lukewarmwater6412 i think these actually aren't very expensive the guy who runs the Chanel mentioned somewhere that they are like 1.5€ a piece. But yeah coolant would help massively here. But i think it's just the age of this mashine.
@@kingofl337 Work hardening is triggered by deformation, not by heat. Cooling could perhaps make a small difference by prolonging tool life, since dull cutting edges tend to smear more, but that's only a guess on my part.
@@oliviercoen446 There are basically 3 different mechanisms by which metals and alloys accommodate deformation. Dislocations, twinning or phase transformation. Which one applies is determined by chemical composition. Ductile metals and alloys deform through formation of dislocations. Think of those as atom stacking faults which can move around. A high local deformation increases the dislocation density to a point where the stacking faults get in the way of each other. If dislocations have a harder time moving around, the metal cannot allow the deformation as easily. The strength increases because of plastic deformation.
we wont ever know.. All cos they wouldnt use lubre they kept wearing the cutting inserts and replacing them eventually going bankrupt.. there not cheap to replace those inserts
Exactly my thought... Also, it would prevent the risk of those red-hot chips catching fire - extinguishing which is next to impossible AFAIK. And then the intermittent cooling of hot carbide tips - wouldn't they crack from it?
Manually pouring coolant on the tool head will wear the inserts out. Either steady cool or not but intermittent cooling by manually pour coolant on a extremely hot cutting tool is not good I’d assume right??
Yes they will ignite. Not to mention, you really should t intermittently dowse inserts with coolant. They will thermal crack. Just throwing it out there. I’ve cut tons and tons of ti in all grades. Best way to cut is with steady coolant or cutting oil.
The grinding dust is what you really have to be careful of. I worked for a company that centerless ground titanium rods and once the guy operating it started it before flooding it with coolant and youd swear it was gunpowder igniting. Not easy to extinguish either
Alot of US companies have privacy rules about it. At least my company does. We are not allowed to even have our cell phones on the shop floor let alone try to take a picture or video.
I have to imagine this was the guy's first day on the job. I've never seen a machinist watch his drill head turn orange from heat and either not turn it off or realize he'd forgot the coolant
Nah he knows what he’s doing. Not to be rude but it just shows how much you know by calling it a “drill head” lol. It’s a given that on the raw rough surface of forged titanium, especially such a massive piece, inserts are going to be wore out so once that happens it doesn’t matter if he goes a bit longer and gets them more dull because they are already finished. Plus they are a disposable and replaceable part of the tool. Also the tool itself isn’t getting red hot, that’s the chips. If you want to see another crazy example of this look up ceramic endmill cutting nickel based allow like inconnel 625 or something
The thermal shock introduced by coolant to such a meaty interrupted cut would likely kill the inserts quicker. Coolant in a turning op, like you say, may have some benefit since it's uninterrupted.
All the negative comments , he blasted that Titanium without damage ! Job shops that deal with super alloys don’t worry about insert cost they spend the money for development!
The old masters told me that titanium is best cooled with plain water. They say that coolant for some reason contributes to the rapid wear of the tool and high heating, and with water it is cut much better.
SomeSay: Waterbased coolants are what your “old masters” meant. You add 50:50 coolant concentrate to water, but need to filter and clean the sump or it sticks up quickly.
To all the coolant junkies is said: This is a open machine. No housing. Flood cooling impossible. Cooling means the operator is standing in the coolant rain. It`s my job, I know what I`m talking about.
The thumbnail made me think this was a rolling machine that rolled a big thick piece for a tank or something. Like half a bus in size. Then noticed the sides are cut. So then thought it was a solid chunk. LIKE WHAT WAS THAT GONNA BE USED FOR. Then watched the video :)
The temperature is the enemy number 1 of the cutting tools. If that milling has a constant fluid of cooling on the cutting tool they last the entire process and more.
I am often confused as to why fluids are not used in the cutting process so often. Cutting fluid as a coolant actually improves the cutting speeds as well as tool life.
@@thomasstuart6861 No, not necessarily... in Turning and Holemaking coolant is essential for the tool-life. But when milling structural and tool steel it is often counterproductive. Modern coatings on carbide tools need the heat to work; thermal shock is cracking the coating when milling with coolant; the stick-slip-effect is important when milling with negative tools and/or large overhangs. Mostly tools die and wear of poor chip evacuation when machining without coolant. An airblast nozzle will work wonders. When it comes to HRSA or martensitic/stainless steels you will need coolant because of the bad thermal conductivity and stickyness of those workpiece materials. Certain modern and expensive coatings with smoothening surface treatments however can work on those workpiece materials without coolant.
@@thomasstuart6861 idk about that handbook. Is it that special american book? Heard lot of good things about it. I am trained as an optimizer for machining. I do read a lot of articles und publications but since im from Germany mostly in german. That is why my english is not exactly good. 🙈
@@timhoppmann3938 The Machinery handbook has been the definitive authority of engineering, manufacturing and machine technology for a hundred years of more but my copies are old. As an optimizer I would expect you could write a book on speeds/feeds and tooling. I have always been impressed with the new machinery techniques that from my perspective seem almost magical. However, I have recently watched a test on the use of an assortment of cutting fluids and poor quality drills. The results were astounding and not intuitive at all. I have always been disappointed by the failure rates in drill and tapping 4-40 threads and the type of cutting fluids make so much of a difference it is more of an occult science than logic.
No coolant will create alpha case and the material will be brittle with alot of micro cracks. It will reduce the performance of the metal and it´s fatigue properties.
If a mirror finish is needed, you can remove 7 of the 8 tips and run the millhead with one tip only. Slow down the feed rate and speed up the spindle rotation, cutting depth 0,05 - 0,1 mm only.
0.05 cut depth with an insert that probably has a bigger radius then 0.1 is not going to give a good finish at all. I havent looked at the inserts in the finishing tool, but the first inserts had a huge radius on them. Those want a big chip or they wil not work wel.
Thermally induced micro-fractures.. the heat from the contact during the cut and the subsequent and immediate cooling of the carbide insert cause fracturing of said insert and then the insert almost explodes.. it's better to keep the heat in the chip that is being removed.. that being said, there is a balance between tool life and material removal when it comes to profit margins.. machining is a fickle business.. not easy to make money without the proper tools and knowledge.
Probably a silly question as I am not a machinist but why do you not use coolant for cutting this titanium... I would love have thought a mist coolant spray would be better than a drink bottle of coolant
@@diegoceballos6871 lol stop acting like you have a clue. There are several ways to cool/lube that depend on the application and design parameters. Go make a rake.
If you run the feed the other direction and use coolant continuously you'll not be seeing them little red fingers of death or chips on them when the come out.
@@jackmclane1826 That's just the oxide "crust" on the outside of the part. Watch some videos of the forging process, you'll see this crust being formed and crushed in the high heat process.
Processed later down, we have bigger pieces than that at my work. We forge it down to 172mm. After that it will be used fore diffrent things, like pipes fore nuclear powerplants.
Pretty much guaranteed the end isn't perpendicular to the axis, but that doesnt matter. The forging is pretty uneven. You can see flat spots, dents, and cracks in the surface that all need to be milled away. The end he just cut just has to be close enough, then the rest of the part will be milled true to the end.
"So, uh, Jim. How many inserts did you go through on that titanium job?"
"Yes"
That's the Boss asking, right? 😎
Either use coolant or do not, it fractures inserts when you intermittently apply coolant to the hot surface.
I wonder if they ever set one on fire... A chunk of titanium like that would probably be like a nuclear meltdown.
carbide micro fracturing is a bitch...so is titanium (inconel isn't too fabulous either). The ONLY cool thing I like is the magnesium-esque fire/burning properties
@@jasonaldenhaley1 I've never set any on fire -- even grinding it a little. A machinist friend said someone at his shop set one on fire with a milling machine and it was just impossible to put out. Burned up a lot of expensive equipment before it burnt itself out. I do know that grinding in on a regular home shop type grinding wheel produces the longest and brightest white sparks I've ever seen.
@@luke_skywanker7643 I'd purposely take a super light cut for that 'S.O.S.' pad chip ball and then she'd light up SUN-BRIGHT and no, not puttin that out. I couldn't imagine surviving a plane crash just to...omg, don't even wanna think of that stuff burning a person!!! Million degree burns right there... hopefully get out AS SOON AS POSSIBLE!!
@@jasonaldenhaley1 True. Magnesium and aluminum are pretty bright and hot when they catch fire -- but nothing like titanium. Titanium is also supposed to be "water reactive" when it gets to about 1,300f. It breaks down the water, absorbing the oxygen and releasing the hydrogen, causing an explosion.
A quick 7 minute 10 second guide on How to ruin inserts and work harden titanium😄
titanium is an abbreviation for "no, you dont have enough inserts"
I can’t believe that such a large milling machine like that doesn’t have a coolant system to keep the cutting inserts from getting very hot and apparently wearing out in short time period!
agreed ... coolant saves inserts
yeah, me too, the inserts are not cheap!
@@lukewarmwater6412 i think these actually aren't very expensive the guy who runs the Chanel mentioned somewhere that they are like 1.5€ a piece.
But yeah coolant would help massively here.
But i think it's just the age of this mashine.
@@bobvinson3601 coolant on milling ops kills inserts. It's called thermal shock.
Could have internal cooling? I've seen that before
Ahhh G5 Ti, the barstard love child of 316 and Aluminium with a copper grand parent (for the work hardening and Redhead like temperament)
Oooohhhhh! As a metallurgist myself, I love that analogy!
This is just ace!
So shouldn’t they have been pouring huge amounts of coolant to stop work hardening?
@@kingofl337 Work hardening is triggered by deformation, not by heat. Cooling could perhaps make a small difference by prolonging tool life, since dull cutting edges tend to smear more, but that's only a guess on my part.
@@oliviercoen446 There are basically 3 different mechanisms by which metals and alloys accommodate deformation. Dislocations, twinning or phase transformation. Which one applies is determined by chemical composition.
Ductile metals and alloys deform through formation of dislocations. Think of those as atom stacking faults which can move around. A high local deformation increases the dislocation density to a point where the stacking faults get in the way of each other. If dislocations have a harder time moving around, the metal cannot allow the deformation as easily. The strength increases because of plastic deformation.
I just want to see the rest of the job being machined, and maybe what it’s used for!! Lovely to watch as usual James
Epic Beyblade
Huge doorstop.
It's a tp holder guys ....just look at it
we wont ever know.. All cos they wouldnt use lubre they kept wearing the cutting inserts and replacing them eventually going bankrupt.. there not cheap to replace those inserts
Titanium does not conduct heat so all generated heat goes into the tool. drives me crazy to not see coolant and burning up incerts
And this is why you always have a second cutter loaded with fresh inserts ready to go. Monumental down time when stopping to index after every pass.
Shouldn’t you use flood coolant? Your tooling would last longer
Exactly my thought... Also, it would prevent the risk of those red-hot chips catching fire - extinguishing which is next to impossible AFAIK. And then the intermittent cooling of hot carbide tips - wouldn't they crack from it?
Manually pouring coolant on the tool head will wear the inserts out. Either steady cool or not but intermittent cooling by manually pour coolant on a extremely hot cutting tool is not good I’d assume right??
What? No brain dead, mind numbing music?! Great!
Great to see this old tech still being useful. Do be careful, Ti chips can and will ignite.
Yes they will ignite. Not to mention, you really should t intermittently dowse inserts with coolant. They will thermal crack. Just throwing it out there. I’ve cut tons and tons of ti in all grades. Best way to cut is with steady coolant or cutting oil.
The grinding dust is what you really have to be careful of. I worked for a company that centerless ground titanium rods and once the guy operating it started it before flooding it with coolant and youd swear it was gunpowder igniting. Not easy to extinguish either
It's interesting to see not many videos from US about big horizontal and milling CNC machines.
Alot of US companies have privacy rules about it. At least my company does. We are not allowed to even have our cell phones on the shop floor let alone try to take a picture or video.
That’s a huge piece of titanium round bar.
I have to imagine this was the guy's first day on the job. I've never seen a machinist watch his drill head turn orange from heat and either not turn it off or realize he'd forgot the coolant
Nah he knows what he’s doing. Not to be rude but it just shows how much you know by calling it a “drill head” lol. It’s a given that on the raw rough surface of forged titanium, especially such a massive piece, inserts are going to be wore out so once that happens it doesn’t matter if he goes a bit longer and gets them more dull because they are already finished. Plus they are a disposable and replaceable part of the tool. Also the tool itself isn’t getting red hot, that’s the chips. If you want to see another crazy example of this look up ceramic endmill cutting nickel based allow like inconnel 625 or something
@@Willytg7 Riiiight.... Tell yourself whatever you need to joker
@@ThisManTriggeredMe probably doesn’t know the difference between a drill press and a mill lol
I used to turn a lot of titanium and one thing for sure is you need coolant constantly on your tooling to get the most out of it.
The thermal shock introduced by coolant to such a meaty interrupted cut would likely kill the inserts quicker. Coolant in a turning op, like you say, may have some benefit since it's uninterrupted.
Great content this helps me see myself running a horizontal mill.
don't get too pumped ..after 2, 3 weeks it'll seem a whole lot like work!!! i said the same about giant magnet crane at the scrap yard!!
@@jasonaldenhaley1 I love my work but thank you for the feedback.
All the negative comments , he blasted that Titanium without damage ! Job shops that deal with super alloys don’t worry about insert cost they spend the money for development!
Must have a big box of inserts laying around.
A 10mm depth of cut?! This is so cool to watch!
I don't want to to consider the cost of the forging, never mind the finished product.
Wild shit.. TI is crazy. I can imagine the load on the cutting head motor.
The old masters told me that titanium is best cooled with plain water. They say that coolant for some reason contributes to the rapid wear of the tool and high heating, and with water it is cut much better.
Wait, like what?
If anything these coolants prolong the life of tools. Idk why they'd think a oil/water mix would increase friction.
SomeSay: Waterbased coolants are what your “old masters” meant. You add 50:50 coolant concentrate to water, but need to filter and clean the sump or it sticks up quickly.
@@jeremyclarkson6035 I think if someone say "just pure water" he mEaNs a PURE WATER. What a fckn plottwist!
@@Ma_X64 When using a QTip stop pushing when you feel resistance.
@@jeremyclarkson6035 LOL! You should have told him that a decade ago, Jeremy. NOW look at him.
Tail hooks on some Navy jets are 6Al-4v-2Sn. Kind of hard to cut compared with the other Ti alloys.
Holy fucking shit. I can’t imagine how much that piece or titanium cost. I would estimate around 150-200k.
To all the coolant junkies is said: This is a open machine. No housing. Flood cooling impossible. Cooling means the operator is standing in the coolant rain. It`s my job, I know what I`m talking about.
Better off just running with no coolant because when he squirts it onto the hot inserts it creates thermal cracking reducing the life
They will be turning this into a titanium toothpick. Material removal 99.9999%. That's alot of chips.
Gosh the camera shots first convince you it's like, it 12 feet diameter, then you realize, it's probably 6 in, Oh so it's 18" ?
you recked the inserts by poring water on the carbide dork.
CNC machine owners will use this to make a part the size of a toothpick.
Willing to bet not 10% percent of commenters have ever machined this type of material.
Your point being?
@@4.0.4 My point is, I have a gambling problem. WTF do think the point is?
Im not a metals expert but for some reason i expected titanium to be black like the sr71. lolz. But this vid makes it look like another steel alloy
Titanium foundry is a fucking crazy process more than cnc I think , but still impressive
The thumbnail made me think this was a rolling machine that rolled a big thick piece for a tank or something. Like half a bus in size. Then noticed the sides are cut. So then thought it was a solid chunk. LIKE WHAT WAS THAT GONNA BE USED FOR. Then watched the video :)
What customer needs to use a piece of titanium that large in any particular machine work that's huge
What do you do with the old chips? Sell them to recycler?
Wow thats some tough stuff!
I found personally machining titanium quite nice, only what i really dislike is that chippings can easily get on fire... and they burn hot as hell....
Wow, seeing red hot chips. Surprised there is no constant coolant flow to facilitate this cut.
The temperature is the enemy number 1 of the cutting tools.
If that milling has a constant fluid of cooling on the cutting tool they last the entire process and more.
I am often confused as to why fluids are not used in the cutting process so often. Cutting fluid as a coolant actually improves the cutting speeds as well as tool life.
@@thomasstuart6861 No, not necessarily... in Turning and Holemaking coolant is essential for the tool-life. But when milling structural and tool steel it is often counterproductive. Modern coatings on carbide tools need the heat to work; thermal shock is cracking the coating when milling with coolant; the stick-slip-effect is important when milling with negative tools and/or large overhangs. Mostly tools die and wear of poor chip evacuation when machining without coolant. An airblast nozzle will work wonders. When it comes to HRSA or martensitic/stainless steels you will need coolant because of the bad thermal conductivity and stickyness of those workpiece materials. Certain modern and expensive coatings with smoothening surface treatments however can work on those workpiece materials without coolant.
@@timhoppmann3938 I appreciate the depth of your reply....I will want to look into this more. Does the machinery's hand book have anything on this?
@@thomasstuart6861 idk about that handbook. Is it that special american book? Heard lot of good things about it. I am trained as an optimizer for machining. I do read a lot of articles und publications but since im from Germany mostly in german. That is why my english is not exactly good. 🙈
@@timhoppmann3938 The Machinery handbook has been the definitive authority of engineering, manufacturing and machine technology for a hundred years of more but my copies are old. As an optimizer I would expect you could write a book on speeds/feeds and tooling. I have always been impressed with the new machinery techniques that from my perspective seem almost magical. However, I have recently watched a test on the use of an assortment of cutting fluids and poor quality drills. The results were astounding and not intuitive at all. I have always been disappointed by the failure rates in drill and tapping 4-40 threads and the type of cutting fluids make so much of a difference it is more of an occult science than logic.
Try cutting width 70% and use coolant every time cutting
No coolant will create alpha case and the material will be brittle with alot of micro cracks. It will reduce the performance of the metal and it´s fatigue properties.
Those are some major cracks
If a mirror finish is needed, you can remove 7 of the 8 tips and run the millhead with one tip only. Slow down the feed rate and speed up the spindle rotation, cutting depth 0,05 - 0,1 mm only.
0.05 cut depth with an insert that probably has a bigger radius then 0.1 is not going to give a good finish at all. I havent looked at the inserts in the finishing tool, but the first inserts had a huge radius on them. Those want a big chip or they wil not work wel.
must put cold water lubricant while cutting the metal
Would love a barrel full of those chips , smelt them down and pour round stock
I am a simple person - I see Titanium, I think “aww…. SR-71 Blackbird” :)
Scary seeing red-hot titanium chips curl off that thing... Good thing they're thick enough not to self-ignite, I guess. Yikes!
I've never machined titanium but why are you not running constant coolant?
Thermally induced micro-fractures.. the heat from the contact during the cut and the subsequent and immediate cooling of the carbide insert cause fracturing of said insert and then the insert almost explodes.. it's better to keep the heat in the chip that is being removed.. that being said, there is a balance between tool life and material removal when it comes to profit margins.. machining is a fickle business.. not easy to make money without the proper tools and knowledge.
Probably a silly question as I am not a machinist but why do you not use coolant for cutting this titanium... I would love have thought a mist coolant spray would be better than a drink bottle of coolant
parece que eres el único que se ha dado cuenta.
@@diegoceballos6871 lol stop acting like you have a clue. There are several ways to cool/lube that depend on the application and design parameters. Go make a rake.
А это вообще легально так жарить фрезу?
Would it not make sense to grind the bark off of that face and save your inserts ?
I'm curious. Why the reverse face cutting. Allows heat to build faster on tooling
I wonder what is the reason they start with round forged bar. It seems much less efficient than working with rectangular stock
Well, it said this is just to prepare it for saying, I'd assume this is raw stock for lathe parts
To be used for what?
Making chips?
Saw the thing.
If you run the feed the other direction and use coolant continuously you'll not be seeing them little red fingers of death or chips on them when the come out.
this is one of those jobs where if you screw up , youre wife files for divorce.
The quality of that stock is amazing Forged to within 15mm of square and it looks like the diameter would be less than 10
it's not that hard actually. Modern forging machines have encoders so the operator knows how far he squished the forging exactly :D
On the other hand it looks like the piece has countless fractures... is that normal?
@@jackmclane1826 That's just the oxide "crust" on the outside of the part. Watch some videos of the forging process, you'll see this crust being formed and crushed in the high heat process.
@@chronokoks _"squished"_
Look at you and your fancy forging terminology 😁
@@ferrumignis not as fancy as your name :-D
running that tool way too hot with that many chips in the pan, are you not aware of the dangers of a titanium metal fire?
You need to post how long this stuff takes you and how many inserts you use and how much it cost per insert
Одна сторона в повітрі!
And that's just facing it ...
How much does that bar weigh?
I have machined a lot of grade5 and 2.
Its not easy. Need skills to handle it.
It was never done without cooling.
Does anyone know what this huge piece of titanium would be used for? Or will it be cut up and processed later on down the road?
Processed later down, we have bigger pieces than that at my work. We forge it down to 172mm. After that it will be used fore diffrent things, like pipes fore nuclear powerplants.
So what is this for? Is this for raw material cost efficiency? Or is something large going to be machined out of this?
how much does one pay for such a big piece of Titanium?
No coolant?
What's your depth of cut?
這個工件是鍛造鋼吧?怎麼加工機沒有自動噴水的設備?
that is some scary looking metal....
not the hulk of the billet....
the little crisps.
Bar cost more than 100k $?
слышал байку, что раскаленная титановая стружка прожигает части станка насквозь...
как оказывается это не та:)
Горящая прожигает. Но титановые сплавы разные бывают.
Certainly putting heat in some of those chips!
only on three feet ... the gap between one foot and the piece ... I was just wondering if the end can be perpendicular to the longitudinal axis ??
Pretty much guaranteed the end isn't perpendicular to the axis, but that doesnt matter. The forging is pretty uneven. You can see flat spots, dents, and cracks in the surface that all need to be milled away. The end he just cut just has to be close enough, then the rest of the part will be milled true to the end.
What is it going to be used for??
Why would anyone squirt milk on the cutter?
Isn’t that like Space Grade?
Why dont you use constant coolant instead ?
Por qué no le pones aíre a la herramienta directamente?
Surprised you're not flooding it
Just curious what that blank stock cost. I bought a small 1” x 5” and it was pricey
It probably costs less per pound but this is probably very expensive
What's a piece that big gonna be used for?
Why no coolant?
James what's it the red bits that flying ?
1обороты низкие 2против шерсти фрезерует
What would the rough cost be of the bar to begin with? A couple thousand dollars?
Titanium forging like this, add another zero.
Un poquito de taladrina no?
How to machine titanium…..
Machine: EEEEEEEEEEEEEEEEEEEEEEEEE!!!!!!!!!!!!
Use Ceramic inserts and SPEED it up to VC=700 m/min and Fz=0.12 to Fz=0.4mm and smile about the "wear",
there is NONE !!!!!!
Why are then inches on your tape measure so short?
cm
@@kornaros96 whoosh
What do they do with all the chips??
Is that a hmc or a boring mill?and whats the difference between the two
How much did that billet cost!!!
How deep do those fissures in the rough stock go?
I thought Titanium was EXPENSIVE, or are they making shavings for a reason?
Well it's either this or a magical wand to make things shape shift into what you want.
Do you reclaim all the swarf?
I should hope so, quite a bit of value in those chips.
How much does that piece cost?
Nice 👍. Is it a manual hbm or does it have some sort of control? Best regards
There are multiple shots of the control screen in the video
@@elanjacobs1 yes i Saw that. But thought it were a kind of dro 😀
You seem to take large amounts off, I’d have thought you’d remove the minimum to get a flat surface.
Is there a reason you take so much away?
Look at 1:25 how much it curves at the edges. They have to remove material to this point for a flat surface with a 90° corner.
@@davezad fair point, and actually the 10 or so mm removed is a small percentage against the size of the block.