You will have to unfurl the thread reel until the thread on the reel runs out.

[tufguy]

1) You will have to unfurl the thread reel until the thread on the reel runs out.

2) You will have to unfurl the thread reel until the thread on the reel finishes.

Please check my sentences.

 

[tedmc]

I would say:

You will have to unwind the thread from the reel until the end.

 

[Tdol]

It is simply too much information, including details for accuracy that turn the sentence into a maze. We don't need every possible detail unless we're writing a legal contract. Make it simpler:

Unwind all the thread from the reel.

 

[tedmc]

You do not have to unwind something to the end, do you?
If that was what the writer intended to say, why leave that out?

 

[tufguy]

Tdol suggested Unwind all the thread from the reel.

Okay, I got it but in case we have to use either one "end" or "finish" so which one should be used for thread? Unwind the reel until thread finishes or ends.

 

[probus]

Thread is wound on spools, not reels. Fire hoses come on reels. Film and audio tape too, in olden days.

 

[emsr2d2]

Cotton, which is a type of thread, comes on reels. Specifically, it comes on cotton reels.

 

[emsr2d2]

... and cotton reels

 

[GoesStation]

... and cotton reels

Another BrE/AmE difference! Those are spools of thread to me. It wouldn't occur to me to call them reels.

 

[probus]

Another BrE/AmE difference! Those are spools of thread to me. It wouldn't occur to me to call them reels.

I agree. The association of reels with fire hoses is so strong where I live that some people call fire engines fire reels.

 

[tedmc]

Apparently they are synonyms.

https://www.google.com/amp/s/dictionary.cambridge.org/amp/english/spool