Bad idea?

If you only need 4 foot cables, I don't see why not.  Seems like a good idea.  From the other posts, there are lots of good options and it is easy and clean to have them terminated by the pros.  My buddy terminated his cables with good connectors and shrink wrap and they look just like from a factory.  I personally don't care for bare wire.  Do you have a speaker cable picked out yet?  I keep think about new cables and was told DH labs T-14 is good, but I have not tried it. 

https://silversonic.com/products/bulk-cable/

@OP If you can't solder, buy cables in the correct length instead. In fact, that is the better way to go anyway.

Many good choices here, Cullen, Pine Tree.   You might also check out Ice Age Audio up in Traverse City, MI

My next purchase will be @daledeee1's suggestion ... full set-up for $110  ... 

https://sites.google.com/view/pine-tree-audio/speaker-cables/speaker-cables/shadow-ribbon

Don’t cut and terminate yourself unless you are experienced.  Rather, audition the following WyWires model:
https://wywires.com/collections/speaker-cables/products/speaker-cables-blue

Read the following Absolute Sound review below:

$299/4′ pr. interconnect (RCA or XLR); $449/8′ pr. speaker 
The first WyWires cable reviewed in TAS, the Blue is also one of the most pliable, easy-to-handle cables around. Its sonic signature is energetic, with a potent midrange, plenty of drive, and a slightly cooler, forward tilt.

Also read:

https://www.hifipig.com/wywires-blue-interconnects-and-speaker-cables/

In 99.9% of systems, the person would be better off by saving that money toward a speaker upgrade. 
 

Otherwise, just get a couple 4’ lengths of the 12-gauge Duelund cable from Parts Connexion. It’s all anyone needs.