Torx drill bit as a hobbed bolt alternative?

I've been thinking about using Torx drill bits, like theese, as an alternative to hobbed bolts.
They are pretty much standarized (hobbed bolts are clearly not, I have 3 of them, 2 from the same supplier, and all of therm look COMPLETELLY different), robust, cheap, and a lot lighter (in weight) too.
I did a bunch of manual tests and it seemed there was enough grip, better with ABS.
Have anyone tried them before?
Can anyone see any problem in using them?

I already have a post in the mechanics forum take a look it's got a lot of my feelings on what's wrong with the basic extruders

The edges of the Torx Bits are nicely rounded, you could squash filament with them, but thats it.
You need a sharp edge that cuts into the filament to precisely transport it towards the hotend.

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[www.bonkers.de]
[merlin-hotend.de]
[www.hackerspace-ffm.de]

I have been having success with my hobbed bolts because I thought about it when I first started having problems of stripping the filament, clogging and misalignment.
I overcame all the problems by simply using a very large tap to cut the teeth on the hobbed bolt.
It still has sharp teeth so it grabs the filament no problem.
Having large teeth they are flatter so the alignment problem has gone too.
Also having large teeth, the clogging problem was completely eliminated.

Just my two cents worth, works for me.

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[regpye.com.au]
"Experience is the mother of all knowledge." --Leonardo da Vinci

I cut my bolts with pretty large teeth as well. They perform a lot better than the finer cut ones i tried. The most important thing is that the edges are really sharp.

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[www.bonkers.de]
[merlin-hotend.de]
[www.hackerspace-ffm.de]

I think it quite differently, sharp teeth will bring grip, but they have the terrible side effect of grinding the filament (see in the post below).
Square teeth are better in this way.

I found a problem with torx round teeth too: they need really high idler pressure, much higher than i thought....

I found another design, MoonCactus hobbed bolt, it is really easy to make with a dremel.
He explains it better in this blog post.
The only problem i found with this last one is because it is incompatible with all "famous" extruders, but I'm designing a new extruder anyway....

Quote
ibpsrs
I think it quite differently, sharp teeth will bring grip, but they have the terrible side effect of grinding the filament (see in the post below).
Square teeth are better in this way.

I found a problem with torx round teeth too: they need really high idler pressure, much higher than i thought....

I found another design, MoonCactus hobbed bolt, it is really easy to make with a dremel.
He explains it better in this blog post.
The only problem i found with this last one is because it is incompatible with all "famous" extruders, but I'm designing a new extruder anyway....

Use a dremel to cut a 1 mm groove in this little gear - no stripping of filament
gears available at aliexpress [www.aliexpress.com]

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You only learn when you change your mind.
[www.deltaprinter.co.za]

If your bolt is grinding the filament you have a different problem. Either your idler pressure is way to high or the pressure in the hotend is simply to high.

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[www.bonkers.de]
[merlin-hotend.de]
[www.hackerspace-ffm.de]

Quote
Srek
If your bolt is grinding the filament you have a different problem. Either your idler pressure is way to high or the pressure in the hotend is simply to high.

A good hotend overcomes these problems a lot.

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[regpye.com.au]
"Experience is the mother of all knowledge." --Leonardo da Vinci

It doesn't seem the problem is idler pressure, but, aggressive retraction settings, that make my prints look a lot better.

I think that sharp teeth repeatedly hitting the same spot of the filament was grinding it.