Shawnsel, you are a very thorough individual.
Razor manufacturing methods: Is Machined > MIM > sintered > casted ?
- Thread starter shawnsel
- Start date
Personally, I'm not sure the webers actually have a manufacturing tolerance problem that sometimes results in wavy blades. In many cases, the user describing the problem was using blades that had glue/wax dots holding them onto the paper wrappers. The build up from that glue/wax may be what resulted in the issues the user observed. I use mine glue dots down and have no problems
I wish I could agree with you, however I only use Personna labs or med preps, neither of which have glue spots, and my Weber has the wavy blade issue. I've even tried loading the same blade in different razors and they all held it dead straight, not so the Weber. I don't know whether it came out of the mould like that or if it was down to over-enthusiastic polishing, but IMO it should not have left the factory. My previous Weber had the same problem only worse.
Shawn, I'm only seeing the "Head Construction" column. If that's what you mean, then certainly no reason to remove that. The key is that it just needs to be factual...interpretation of impact on quality is left to the reader.
Also, as an aside I think you can add HTGAM (Symmetry at least) to the family of Cadet/Pearl/Razrock clones. That's just from me eye balling the razor though in pictures..maybe someone else can more definitively confirm. It's got a different handle, but head appears to the same. http://howtogrowamoustachestore.com/products/the-symmetry-open-comb-safety-razor
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- Thread starter
- #24
Yes, I meant the "Head Construction" column. I was just wanting to check that the manufacturing techniques listed (example: "chrome over cast zinc alloy") were at least debatably relevant information.
Thanks!
Shawn
It's certainly relevant information for me, I like to know what a razor's made of before I buy it.
Personally, I am not interested in a razor made from 316 alloy (which seems to be the most common) or sintered (any alloy, I don't much care for that process). I would consider a machined 303, but would prefer 304 (which is not a shiny stainless). As far as I know, no one makes a 304 alloy razor.
Great information Stan. As I understand it, ATT is 303 while both IKON and Weber are 316. Is the problem with 316 that it will rust over time? Not enough chromium? The claim is that the 316 is "marine grade stainless." What is up with that?
Hi,
It tends to form a light surface rust on the inside due to fresh water having a higher concentration of oxygen in it than salt water has. When the term 'Marine Grade' is used, it refers to resistance to salt water corrosion. It isn't a big deal if you usually take your razor apart and dry it anyway. I don't, only opening mine up once a week for blade changing. And, a light surface film of rust would not affect my useage, but if I were to spend the money required for a stainless steel razor, I would go for a different alloy.
Stan
- Thread starter
- #28
My understanding is that the 316 is one of the more rust resistant alloys (although all SS will rust eventually), but what IKON glances over is that only their handle is 316. Their razor heads are an undisclosed, sintered SS alloy (coated with a DLC).
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According to Weber, their handles are 316, the head is 17-4 PH. As Shawn says, only iKon know what they're using, and they're not telling.
- Thread starter
- #30
Any follow up or additional informed opinions on if specific manufacturing methods (aside from materials) typically yield better or worse results??
And I'll just throw out that by (my perceived) general reputation ... machined seems to be the most precise and consistent?
And I'll just throw out that by (my perceived) general reputation ... machined seems to be the most precise and consistent?
Any follow up or additional informed opinions on if specific manufacturing methods (aside from materials) typically yield better or worse results??
And I'll just throw out that by (my perceived) general reputation ... machined seems to be the most precise and consistent?
Hey Shawn, I still haven't had the cycles to chat with my dad about this...maybe this weekend...
On machining..yeah I would agree that it's probably the easiest to make consistent - limited only by the CNC or lathe equipment you're using, etc. The various casting methods can be very good as well, but you've got some variables to control, like material shrinking. Both processes can certainly get you to razor level tolerances, but in practice machining is going to be easier for small shops to implement. Those kinds of places are typically not going to have the engineering skills on staff to deal with difficult materials issues. It's very complicated.
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- Thread starter
- #32
This is still an interesting question to me ... does anyone have further thoughts?
Thanks!
Thanks!
Hi,
Well, I think Old King Camp had the best material picked when he opted for brass. Can be formed or machined or in combination and is corrosion resistant in pretty much any water.
I would use 304 stainless, as it is resistant to even most corrosives. But it is hard on the tooling and it isn't shiny. So, quite expensive and is why no one opts for it. Last winter I played with recreating my Fasan Double Slant out of 304. The head came out well, the baseplate I screwed up.
Stan
Well, I think Old King Camp had the best material picked when he opted for brass. Can be formed or machined or in combination and is corrosion resistant in pretty much any water.
I would use 304 stainless, as it is resistant to even most corrosives. But it is hard on the tooling and it isn't shiny. So, quite expensive and is why no one opts for it. Last winter I played with recreating my Fasan Double Slant out of 304. The head came out well, the baseplate I screwed up.
Stan
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WARNING: INCOMING WALL OF TEXT DETECTED!
I'm certainly not an engineer or a materials expert, but I'm going to chime in anyway. Please know that I am 100% talking out of my butt here, but hopefully if I say something that's too stupid, someone who knows more than I do will jump in and educate me. Be forewarned that reading this might educate you, but it also might make you dumber, so proceed with caution.
First off, a tolerance is just the amount of variation possible from one manufactured part to another. Think of it as "accuracy." If I'm hand-carving a part out of wood, each one is going to be a little different than the one before it, no matter how hard I try to make them the same. Low tolerances aren't necessarily a bad thing. If I'm hand-carving a fine pipe, it's not too big a deal of one is 0.5mm longer than the next. In fact, this uniqueness is often desired. But if I'm making a pressure valve for the space shuttle fuel tank, and it's is off by 0.001mm, things could get all explodey. If I'm making an artificial knee for a patient out of titanium, and I'm off by just a litte, that person might end up living in pain for the rest of their lives.
In regards to a razor, tolerances matter quite a bit. Someone above noted that you can't feel a difference of 0.1mm on your face. While that's true, that small difference could make a huge difference in the shape or angle of the blade. It could also significantly affect how the top and bottom fit together, and thus have a drastic effect on how much blood you get to keep in your face.
Casting, or more specifically gravity casting, is just the process of pouring molten liquid into a negative cavity and allowing it to harden. One really important thing I've read that few people seem to be aware of, though, is that when the material cools and hardens, it shrinks, (or sometimes expands) and deforms from the shape of the original mold. Different materials deform by different amounts and in different ways. I think this is incredibly important when it comes to the manufacture of razors, because when the engineers design a mold, they take this shrinkage into account, but can't always perfectly predict what's going to happen to the soft, cooling metal as it pulls away from the walls of the mold. This is one of the reasons that Zamak is so popular with manufacturers, because it shrinks very little, (<1%) and very predictably. Aluminum, on the other hand, can shrink as much as 6.5%, so is much more difficult to cast accurately. Because of this shrinkage, there is going to be some inherent inconsistency from one part to another, and that is one of the things that people talk about when they mention tolerances. Also, as the molds continually expand and contract as a result of the heating process, they also deform over time. This can cause changes in how the parts fit together, and can cause metal to seep out of the seams in the parts of the mold. (known as flashing.) Some companies *cough*merkur*cough* haven't replaced or re-tooled their dies in decades, and this becomes very apparent in observed variances and general sloppiness in the finished products, which you can no doubt read about on this very forum.
Sintering is very similar to casting, in that a shapeless powder is put into a mold and heated, causing the powder molecules to adhere very tightly to one another. Note, they do not melt. It's a chemical reaction caused by heat and pressure. That pressure is an important part of the equation, because the pressure can also cause the original shape to deform, even more so than casting. However, this is taken into consideration when designing a part, so the end effect can actually be a more stable and predictable shape than gravity casting. On the other hand, there are limitations to the shapes that sintering can produce, since the mold actually must apply pressure during the shaping process. The end result should be a more consistent shape to the final product. However, this process can also fall victim to the same pitfalls as traditional casting. The dies making the products must be properly maintained, so they don't warp over the years. And if not monitored carefully, shoddy products can result. I believe the "waviness" in some Weber heads mentioned earlier in this thread is a perfect example of this. Since there haven't been sintered razor heads around for decades, it remains to be seen how the process will hold up over time. Re-tooling or re-creating a sintering mold is much more expensive than re-tooling a gravity cast mold, so maybe in 40 years, our children and grandchildren will be on this very forum complaining about the inconsistency of iKon or Weber razors.
I know very little about MIM, apart from the Wikipedia article, so my only comment would be that it has the potential to produce relatively cheap metal parts at a high rate. It is essentially a method of casting, but rather than using gravity to feed the metal, it is injection molded. In theory, this could allow for molds to be produced much more cheaply, and the processes to manufacture could be done much more quickly and in a more automated fashion. (i.e. less expensive human intervention.) It would seem to me that it could have the same drawbacks as gravity casting, because you're still putting a hot liquid into a metal mold and cooling it into a solid, but honestly, I don't know how well it holds up in that regard. It's a fairly new process, and I'm not aware of any razors on the market that use this technique for manufacturing. I've heard some rumors about the iKon OSS, but iKon is pretty secretive about its processes, and I'm not sure anyone knows for sure. I've usually seen it in the context of "faster/cheaper" rather than higher quality, but again, I'm not claiming to know this as fact.
You asked about stamping and/or rolling, which most definitely belongs in this discussion. The two processes are basically the same from a design standpoint. Rather than start with a liquid or powder, this process starts with a solid uniform sheet of metal. That metal is fed into a roller or press which can apply dozens or even thousands of tons of force, which can punch holes and deform the metal. It can result in very tight tolerances, since there is no melting or cooling to account for. It's also very cheap to do in large quantities, and can be done very, very quickly. Almost all vintage Gillette razors were made this way, except for a few New Standard and New Deluxe models made in the 1930's. The main disadvantage of this process is that you are very constricted in the design of the part. Since the metal starts as uniform thickness, you can't make a thick, chunky part, or a part that isn't more or less a uniform thickness. You couldn't make, for example, a razor like ATT from a stamping process, since the center of the baseplate is so much thicker than the edges. If you look at the Gillette Tech, for example, Gillette worked around this limitation by pressing a diamond pattern into the baseplate to give it greater rigidity and the characteristics of a thicker razor. But the metal itself is still the same actual thickness through the whole baseplate.
Which brings us to machining or milling. More specifically, in the case of razor heads, I'm referring to CNC milling. Technically, turning metal on a lathe (as in the case of a razor handle) is also machining, but it's a much simpler and less expensive process, and pretty much limited to round or cylindrical shapes. CNC milling is capable of producing incredibly accurate and consistent parts. Almost all parts that require a high tolerance. Airplane parts, medical implants and prosthesis, firearms, high accuracy industrial valves, etc. are almost all exclusively made by CNC milling. Most materials can be CNC milled, and the process can produce almost any shape imaginable. It's a subtractive process, so you start with a block of whatever material you are milling and subtract the parts you don't want to end up with the final shape. Since it's done by a computer/robot arm, it can be incredibly accurate and consistent from one part to the next. Since there is no heat up/cool down in the process, you don't need to worry about shrinkage of the part. It is the modern gold standard for manufacturing, but it's not without its downsides.
First and foremost, the machines are incredibly expensive, and require an expert to operate. The operator needs to know how to program in the three dimensional shapes, but at the same time, needs to know a lot of the materials science about the materials he or she is cutting. Since you start with more material, then cut pieces of it away, there is a significant amount material lost in the process, usually more than the amount in the final piece. Not only are the machines expensive to purchase, they are expensive to maintain. Depending on the hardness of the material you are cutting into, you have to replace the bits fairly often. If the operator isn't well versed on the materials being cut, they can (and often do) break the bits, or even the entire machine. Finally, it's the slowest of all of the processes. Even though the robot arms can move incredibly quickly, the speed at which they cut into the metal can't be rushed. Go too fast, and you risk damaging the milling bit, the machine, the part, or all three. Parts must machined one at a time, so the process doesn't scale at all. The cost to manufacture one part is more or less the same, regardless of whether you need ten or ten thousand. Something like a razor head might take 30-90 minutes to machine for each part. Assuming, say, 60 minutes per part, and allowing for some defects, a single CNC machine can't physically make more than 1500 - 2000 in a year, and that's assuming that machine makes nothing but that same razor for 40 hours per week, 52 weeks per year. You could, of course, spread the job around to several machine shops, but then you have to make sure each product meets the same tolerances and whatever standards you have set for your product.
This is where tolerances come in. Inexpensive CNC machines can make quick, rough cuts, but there will be a lot of variability between parts. On the other hand, extremely expensive machines with high end tooling, make very small, slow cuts, and get a much higher tolerance. Depending on the tolerances required the cost of machining can vary a lot. The higher tolerances require more expensive machines and tooling, and probably a more experienced (read: more expensive) machinist. If you do spread out the manufacture, you need to make sure each and every shop is using the same plans, the same tooling, and cutting to the same tolerances. If you ever wonder why machined razors are so expensive, I hope that this helps to illustrate the reason behind that.
OK, wow, that was a lot of stuff. I hope that it's been helpful. I'll state again, for the record, I'm an IT geek. I watch a lot of How It's Made. That, and Wikipedia are pretty much my only sources of information, so if anyone with more experience wants to correct anything stupid and/or wrong, I will not be offended. I really enjoy learning about this kind of thing, so I would consider it an honor to be corrected by an experienced machinist.
Cheers!
I'm certainly not an engineer or a materials expert, but I'm going to chime in anyway. Please know that I am 100% talking out of my butt here, but hopefully if I say something that's too stupid, someone who knows more than I do will jump in and educate me. Be forewarned that reading this might educate you, but it also might make you dumber, so proceed with caution.
First off, a tolerance is just the amount of variation possible from one manufactured part to another. Think of it as "accuracy." If I'm hand-carving a part out of wood, each one is going to be a little different than the one before it, no matter how hard I try to make them the same. Low tolerances aren't necessarily a bad thing. If I'm hand-carving a fine pipe, it's not too big a deal of one is 0.5mm longer than the next. In fact, this uniqueness is often desired. But if I'm making a pressure valve for the space shuttle fuel tank, and it's is off by 0.001mm, things could get all explodey. If I'm making an artificial knee for a patient out of titanium, and I'm off by just a litte, that person might end up living in pain for the rest of their lives.
In regards to a razor, tolerances matter quite a bit. Someone above noted that you can't feel a difference of 0.1mm on your face. While that's true, that small difference could make a huge difference in the shape or angle of the blade. It could also significantly affect how the top and bottom fit together, and thus have a drastic effect on how much blood you get to keep in your face.
Casting, or more specifically gravity casting, is just the process of pouring molten liquid into a negative cavity and allowing it to harden. One really important thing I've read that few people seem to be aware of, though, is that when the material cools and hardens, it shrinks, (or sometimes expands) and deforms from the shape of the original mold. Different materials deform by different amounts and in different ways. I think this is incredibly important when it comes to the manufacture of razors, because when the engineers design a mold, they take this shrinkage into account, but can't always perfectly predict what's going to happen to the soft, cooling metal as it pulls away from the walls of the mold. This is one of the reasons that Zamak is so popular with manufacturers, because it shrinks very little, (<1%) and very predictably. Aluminum, on the other hand, can shrink as much as 6.5%, so is much more difficult to cast accurately. Because of this shrinkage, there is going to be some inherent inconsistency from one part to another, and that is one of the things that people talk about when they mention tolerances. Also, as the molds continually expand and contract as a result of the heating process, they also deform over time. This can cause changes in how the parts fit together, and can cause metal to seep out of the seams in the parts of the mold. (known as flashing.) Some companies *cough*merkur*cough* haven't replaced or re-tooled their dies in decades, and this becomes very apparent in observed variances and general sloppiness in the finished products, which you can no doubt read about on this very forum.
Sintering is very similar to casting, in that a shapeless powder is put into a mold and heated, causing the powder molecules to adhere very tightly to one another. Note, they do not melt. It's a chemical reaction caused by heat and pressure. That pressure is an important part of the equation, because the pressure can also cause the original shape to deform, even more so than casting. However, this is taken into consideration when designing a part, so the end effect can actually be a more stable and predictable shape than gravity casting. On the other hand, there are limitations to the shapes that sintering can produce, since the mold actually must apply pressure during the shaping process. The end result should be a more consistent shape to the final product. However, this process can also fall victim to the same pitfalls as traditional casting. The dies making the products must be properly maintained, so they don't warp over the years. And if not monitored carefully, shoddy products can result. I believe the "waviness" in some Weber heads mentioned earlier in this thread is a perfect example of this. Since there haven't been sintered razor heads around for decades, it remains to be seen how the process will hold up over time. Re-tooling or re-creating a sintering mold is much more expensive than re-tooling a gravity cast mold, so maybe in 40 years, our children and grandchildren will be on this very forum complaining about the inconsistency of iKon or Weber razors.
I know very little about MIM, apart from the Wikipedia article, so my only comment would be that it has the potential to produce relatively cheap metal parts at a high rate. It is essentially a method of casting, but rather than using gravity to feed the metal, it is injection molded. In theory, this could allow for molds to be produced much more cheaply, and the processes to manufacture could be done much more quickly and in a more automated fashion. (i.e. less expensive human intervention.) It would seem to me that it could have the same drawbacks as gravity casting, because you're still putting a hot liquid into a metal mold and cooling it into a solid, but honestly, I don't know how well it holds up in that regard. It's a fairly new process, and I'm not aware of any razors on the market that use this technique for manufacturing. I've heard some rumors about the iKon OSS, but iKon is pretty secretive about its processes, and I'm not sure anyone knows for sure. I've usually seen it in the context of "faster/cheaper" rather than higher quality, but again, I'm not claiming to know this as fact.
You asked about stamping and/or rolling, which most definitely belongs in this discussion. The two processes are basically the same from a design standpoint. Rather than start with a liquid or powder, this process starts with a solid uniform sheet of metal. That metal is fed into a roller or press which can apply dozens or even thousands of tons of force, which can punch holes and deform the metal. It can result in very tight tolerances, since there is no melting or cooling to account for. It's also very cheap to do in large quantities, and can be done very, very quickly. Almost all vintage Gillette razors were made this way, except for a few New Standard and New Deluxe models made in the 1930's. The main disadvantage of this process is that you are very constricted in the design of the part. Since the metal starts as uniform thickness, you can't make a thick, chunky part, or a part that isn't more or less a uniform thickness. You couldn't make, for example, a razor like ATT from a stamping process, since the center of the baseplate is so much thicker than the edges. If you look at the Gillette Tech, for example, Gillette worked around this limitation by pressing a diamond pattern into the baseplate to give it greater rigidity and the characteristics of a thicker razor. But the metal itself is still the same actual thickness through the whole baseplate.
Which brings us to machining or milling. More specifically, in the case of razor heads, I'm referring to CNC milling. Technically, turning metal on a lathe (as in the case of a razor handle) is also machining, but it's a much simpler and less expensive process, and pretty much limited to round or cylindrical shapes. CNC milling is capable of producing incredibly accurate and consistent parts. Almost all parts that require a high tolerance. Airplane parts, medical implants and prosthesis, firearms, high accuracy industrial valves, etc. are almost all exclusively made by CNC milling. Most materials can be CNC milled, and the process can produce almost any shape imaginable. It's a subtractive process, so you start with a block of whatever material you are milling and subtract the parts you don't want to end up with the final shape. Since it's done by a computer/robot arm, it can be incredibly accurate and consistent from one part to the next. Since there is no heat up/cool down in the process, you don't need to worry about shrinkage of the part. It is the modern gold standard for manufacturing, but it's not without its downsides.
First and foremost, the machines are incredibly expensive, and require an expert to operate. The operator needs to know how to program in the three dimensional shapes, but at the same time, needs to know a lot of the materials science about the materials he or she is cutting. Since you start with more material, then cut pieces of it away, there is a significant amount material lost in the process, usually more than the amount in the final piece. Not only are the machines expensive to purchase, they are expensive to maintain. Depending on the hardness of the material you are cutting into, you have to replace the bits fairly often. If the operator isn't well versed on the materials being cut, they can (and often do) break the bits, or even the entire machine. Finally, it's the slowest of all of the processes. Even though the robot arms can move incredibly quickly, the speed at which they cut into the metal can't be rushed. Go too fast, and you risk damaging the milling bit, the machine, the part, or all three. Parts must machined one at a time, so the process doesn't scale at all. The cost to manufacture one part is more or less the same, regardless of whether you need ten or ten thousand. Something like a razor head might take 30-90 minutes to machine for each part. Assuming, say, 60 minutes per part, and allowing for some defects, a single CNC machine can't physically make more than 1500 - 2000 in a year, and that's assuming that machine makes nothing but that same razor for 40 hours per week, 52 weeks per year. You could, of course, spread the job around to several machine shops, but then you have to make sure each product meets the same tolerances and whatever standards you have set for your product.
This is where tolerances come in. Inexpensive CNC machines can make quick, rough cuts, but there will be a lot of variability between parts. On the other hand, extremely expensive machines with high end tooling, make very small, slow cuts, and get a much higher tolerance. Depending on the tolerances required the cost of machining can vary a lot. The higher tolerances require more expensive machines and tooling, and probably a more experienced (read: more expensive) machinist. If you do spread out the manufacture, you need to make sure each and every shop is using the same plans, the same tooling, and cutting to the same tolerances. If you ever wonder why machined razors are so expensive, I hope that this helps to illustrate the reason behind that.
OK, wow, that was a lot of stuff. I hope that it's been helpful. I'll state again, for the record, I'm an IT geek. I watch a lot of How It's Made. That, and Wikipedia are pretty much my only sources of information, so if anyone with more experience wants to correct anything stupid and/or wrong, I will not be offended. I really enjoy learning about this kind of thing, so I would consider it an honor to be corrected by an experienced machinist.
Cheers!
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- Thread starter
- #35
@chamm,
A long but excellent read. Thank you for taking the time to write that up. If can get some confirmations from research or others on the forum I would like to encourage you to turn your information into a B&B Wiki page
Two notes:
1. I'm only going off of memory right now, but I believe I've read that Metal Injection Molding (MIM) uses sintering-like metal dust suspended in a special plastic that is then pushed into mold, cooled to the point where the metal is solid (like sintering) but the plastic is then melted away. It sounds strange, but I think I've read that while the end result is slightly less dense, it can be more consistent than sintering ... but I couldn't tell you why....
2. I'm pretty sure the Feather AS-D1 and AS-D2 razors are Metal Injection Molded:
http://badgerandblade.com/vb/archive/index.php/t-280882.html
The I Kons might be also, but as you said, they seem to be secretive about their manufacturing.
Cheers!
Shawn
A long but excellent read. Thank you for taking the time to write that up. If can get some confirmations from research or others on the forum I would like to encourage you to turn your information into a B&B Wiki page
Two notes:
1. I'm only going off of memory right now, but I believe I've read that Metal Injection Molding (MIM) uses sintering-like metal dust suspended in a special plastic that is then pushed into mold, cooled to the point where the metal is solid (like sintering) but the plastic is then melted away. It sounds strange, but I think I've read that while the end result is slightly less dense, it can be more consistent than sintering ... but I couldn't tell you why....
2. I'm pretty sure the Feather AS-D1 and AS-D2 razors are Metal Injection Molded:
http://badgerandblade.com/vb/archive/index.php/t-280882.html
The I Kons might be also, but as you said, they seem to be secretive about their manufacturing.
Cheers!
Shawn
Very interesting read Chamm, thank you.
I'm a little confused on this point, and I spent an hour researching, and now am even more confused.
I thought it was exactly the opposite of what you put up there... that 304 was the most common, and that the 316 was more suited to harsher alkaline environments, (like shaving) because of its molybdenum content. I'm certain you would know better than I, as my knowledge is derived from Internet searches during lulls at work, but I thought maybe you got the two mixed up in that post up there? Considering what I've managed to turn up, it seems that either would probably be suitable for most applications, unless you're building a secret underground missile base or something.
- Thread starter
- #38
A clarification on the use of 316 stainless steel in razors ... there are many handles lathed from 316, but I'm pretty sure that NO razor heads are currently made from the 316 alloy. Weber uses sintered 17-4 PH stainless steel for their razor heads. I KON does not share the manufacturing details of their heads, but if you read carefully the 316 is only used to describe their handles.
If I understand this discussion, Feather and iKon may (or may not) "form" their razors out of stainless steel soup.
Above the Tie, however, machines their products from blocks of steel.
Did I get that right?
Above the Tie, however, machines their products from blocks of steel.
Did I get that right?
Kinda sorta. iKon, at least the ones I have seen, appear to be sintered, as are Weber razors. In short, sintering is just heated and compressed metal powder. I have never seen a Feather razor, but a few posts up, someone said they were made from MIM, which I've been reading up on. The concept is in some ways very similar to sintering, except the metal powder is suspended in a wax or plastic binding agent. That's probably the "soup" you're referring to. After it has been shaped, it's heated up enough to burn away the wax or plastic.
Both sintered and MIM metals are porous, which is probably why many are plated. Also, neither process produces parts that can be machined easily, because the pores can cause unpredictable fissures in the material, which may not be visible to the naked eye.
ATT, Tradere, RazoRock and LA Shaving heads are unquestionably machined from solid stainless steel. (or aluminum) I know this because I've seen with my own eyes. I have read with pretty high reliability, but not personally seen, that PILS and early iKon models (S3S, Bamboo, et al.) are also machined. Almost, if 100% of all stainless steel handles are machined on a metal lathe from solid cylindrical stock. There would be little reason to use any other process.
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