I made my chain whip, in aluminium for more lightness. ...
But i'm just thinking if my sprocket is too much worn (as a cat teeths), could i disassemble it ? ![Shocked :o](https://thorncyclesforum.co.uk/Smileys/default/shocked.gif)
Decades ago (the era of freewheels instead of cassettes) I made some chain whips, I could not afford to buy the real thing. Back then if you wanted to custom build a freewheel for different gearing, you needed a couple of chain whips, as at least one of the sprockets would be threaded onto the freewheel body. I badly bent them even though they were made of steel. If you are trying to remove Rohloff sprocket with a DIY whip that you fabricated, I wish you luck at the time when you actually need that luck.
Or, if your chain whip is only to remove a cassette so you can fix a spoke or something, there are simpler ways to do that. I made one that was less than 50 grams, it was a short bit of chain and a cord that you can tie off to the rim. See photo. Some people put their cassette retaining rings on really tight, if you wanted to use a whip substitute like mine, make sure it will work at home first, just in case you need a real whip.
I have also heard of people using a nylon strap (from their luggage) or some light weight rope to serve a similar purpose.
Speaking of whips, something I started to do a few years ago - when you are working with a chain whip, the end of the chain often falls from the sprocket and is quite inconvenient. I bought some tiny little very strong magnets. I use a small magnet to hold the loose end of the chain to the sprocket. Some day someone will get smart and start to put a magnet on the end of the chain on chain whips to serve that purpose. (If nobody patented it yet, I am hereby documenting my brilliant invention.)
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Disassemble it? I assume you mean threaded one, I think not. If you are talking about a splinned one, I assume they are sold disassembled.
I think Dan has custom milled some chainring teeth or something like that to restore the shape of the worn teeth, I however do not have a milling machine.
A good welder might be able to weld on a new sprocket if they had one, but that would require a lot of careful tolerances to make sure that the body and sprocket are alighned correctly and the sprocket is concentric with the body. I have a small AC welder, but I am not capable of that.
For a long trip to the middle of nowhere, I think the splinned carrier would be the best idea, perhaps a spare sprocket and spare circlip. Plus of course the Rohloff tool, in the event that the hub internals need to be accessed.