I worked as a Tool & Die Macheniat and used
all four of the tapers. Plus CNC mashines
with 4 bolt

Nowadays, where the taper  "rubber meets the road" is where ER collets take over. 5C, R8 and other similar collets grip the round stock or round cutting tool at the front end area of the collet but, ER collets grips against the round stock or tool the entire length of the round stock of tool creating for a better accuracy so; all my machine tools are set up with ER collets. I even have ER emergency collets which are used to make custom fixtures.
My ideal milling machine taper would be the ER collet taper machined right into the end of the the spindle that used to contain the R8 taper.

Wished this AI video talked about the very unique Kearney & Trecker 2D Rotary  Mill tool holders. Its a modified 30 taper with unique collets. Very proprietary.

i had to figure out this whole mess with toolholders when i started up. and took me about 6 months and immense pain and confusion, why such a diversity!!
where have you been bro?!!!
My son will inherit this video of yours, I hope!

Before retirement I saw used CNC purchased not for the machine itself but for the tooling that came with it. A plant can have a small fortune tied up in just one particular tool holding system and adding another system is not a trivial problem.

The NMTB milling machine taper dates back to the 1920s cause i have a 1931 kempsmith with a 50 taper.

the real puzzle is how Moore Special Precision Tool Co. could sell very expensive machines utilizing tooling system requiring only right hand rotation relying upon square thread engagement ---no anti-clockwise tool rotation allowed--my solution on my Moore B18 borer was to gun drill the entire length of the 36 inch spindle spline shaft allowing drawbar to hold modified tooling which now spins CW/CCW

Technological wit developes once one unique/ analogue device appears to the world. Morse is the pioneer,  the others are successors who have evolved his invention. Diversity is the sign of upgrade and search of optimal solutions. I think it was inevitable. Sometimes not convenient especially when different machines of different systems/ engineering schools are operated under one roof. But all this diversity despite inconvenience helps our minds be agile.

TLDRof friction coefficients is interference fits. Interesting 8nterplay between markets, R&D and reality is reality will always assert itself despite what money says. Exactly - there's a drive to R&D otherwise the cost of switching platform becomes less than the cost of staying.

Solves a problem until it doesn't then things have to move forward.

And then there's the Jarno taper, invented by a B&S employee in 1888. A Jarno "n" taper is n/8 of an inch at the big end, n/10 at the small end, and n/2 long. Easy to figure, not widely used.

Ref CAT v BT . mill the additional slot in the flange yourself.

What about index machines

In the 1950s BP cost about $1500? My VN ran about $30K. Ford vs Duesenberg LOL

The taper should not cause plastic deformation when it's locked in spindle,  it just need minimum taper lock, so CAT30 to 50 are best. BT30 seems to be good too. For drilling i agree with the hard taper lock in the holder.

Forgot the “C” collet series. Also the DA and ER collets. These are major collets to have forgotten. Some were shown, but not talked about. Also, newer collet systems are improvements over older systems. Additionally, different machinery needs different collets, so even older systems are still used. It’s complicated.

The real question about Morse and B&S tapers are not why they used one particular taper angle, but why (except for the Jarno) is every size very slightly different in what appears to be a random way? There is no apparent advantage to any of these tiny differences over the other.

Quite frankly, the R-8 and “C” type collets are miserable collets. I wish they had never been invented. They didn’t have to use a split collet of that type. They aren’t accurate. Tools can wobble. They’re weak. Also, why would the R-8 be 7/8” and not 1”? It makes no sense.

While standards committees are thought of as a terrible compromise, this taper mess we see more lately is because there are no standards committees that decide what the standard will be before the designs are commercialized. You get the manufacturers together and work the differences out. Yes, it may even take a few years, but it actually works. I was on two of these committees. Not for machine tools. Instead, large companies, usually, as they can afford the research & development small companies may not, design equally workable solutions. Countries and regions are proprietary aboybthose hine grown solutions so their manufacturers tend to use them.

Back before Reagan essentially destroyed the USA machine tool industry, we could come up with standards everyone else would adopt, as our industry was so much larger than anywhere else. But since then, it’s more fragmented.

Why would anyone leave a like (before) we get started? 😅

Manufacturing is set up by design to keep us spending money.  Big business is buying all the tool manufacturers leading to monopoly pricing.  They are constantly changing designs to make things better, maybe a little, but we end up with $100k in obsolete tooling.  Buy tooling from auctions that are in great working order and you will find the inserts are no longer available.  When you look at the drawers full of obsolete cutters and holders, you realize it's just a game to keep the economy spending.

The problem lies in failure to communicate . Because in the end communicating in this case results in reduced  profit. Our tapers better than theirs blah blah blah .

Oh look, it's yet another AI created machine history video by somebody to lazy to actually produce quality work!

How many tapers did Morse create ? As far as I'm aware, no two of his range 0-7 actually uses the same taper.