What I was reading on (primarily jewelry & small stuff) forums is that not all flex shafts are created equal. Some guys who sprang for the Foredom knockoffs were perfectly happy with the motor side of it, but the power cable was significantly stiffer which of course translates to your hand as its trying to make subtle strokes & angles & positioning. Some clones were indistinguishable but only to a certain RPM & then developed some funky harmonics (vibration) which is a bad thing. usually high speed means small burr & finesse operation, the last place you want unwanted buzz. For say wood carving, probably would never notice a difderence? I kind of lost the scent but some clones were able to adapt actual Foredom replacement kits & others less successful, either because they failed to clone it properly or tweaked it on their own without really knowing what they were doing.
Foredom makes a whole bunch of different kinds of handpieces, collets, chucks etc. But I've also read Foredoms really should be hung up on a tree vs flat on a table (even though they sell a pivoting lazy susan type base). So I dunno, as mentioned I dont have one myself, I was just lurking. I got to run my friends briefly at his shop which WAS hung on a tree & it seemed quite smooth but I was conscious of the flex shaft. I'm a longtime handheld Dremel guy so I'm sure just takes getting used to. Holding an entire 'motor' (Dremel) in your hand is not fun over extended periods either.
The flex shaft lubrication & maintenance side is apparently quite important to do regularly. There are some YouTube vids (amounts to basically cleaning &re-greasing when it comes right down to it). This might help visualize the different kinds of ends they use & I think even taht has changed over the years.
Most current and discontinued motors use a Standard S-93 Key Tip Inner Shaft and S-77 Outer Sheath that work with Key Tip Handpieces. Motors that come equipped with Square Drive shafts and sheaths (shown in video clip above) have the letter ‘H’ (Series SRH, TXH, LXH). Square Drive shafting is...
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