dale wrote:

I'm cheap and I don't want to pay for a new patch panel.

What I want to do is simply attach RJ45 plugs to the unterminated
ends and plug them into a cheap switch but... if I wire the plug
to either the 568B or 568A pattern it fails. I know that the
switch is sound as I've tested it working using cables I made up
- which also suggests I'm using the crimps correctly - so what am
I doing wrong?

Either you've got the colours mixed up, or else the previous installer has.
You'll have to pull off a few wallplates and find their allocation, and then
simply copy it in the attic.

Re wiring solid cable straight to crimp plugs, it's poor practice but it
generally works ok. I've done it in our small home network (1 server, 4
desktops, 1 laptop, 1 WAP, 1 router, 2 switches) and we've had no problems
after 2yrs. At some time in the future I'll probably wire it up properly
through a patch panel, probably when we move to gigabit speed.