Hello
Guess what? I am a apprentice trained toolmaker (Royal Ordnance Factories), I am 41 and needed to take the IELTS in order to get my points.
It is a tiring day (about 6 hours) but not too difficult if you concentrate and do some practice tests. (these can be found online look under holmesglen institute of tafe).
If you do a search under "IELTS york" you will also find a post I did that details the entire day along with quite a few replies.
I don't know how to link directly so have a look.
As a toolmaker you should have the where withall to pass with flying colours!

I passed by the way!

If you want my two pence worth I think you should go for it.
If it means you can then go for a 175 (permanent residency) visa it is worth its weight in gold.
You should always try for the best visa you possibly can as the benefits of permanent residency are many.
Medicare, free schooling, the ability to work and live anywhere and the little known benefit that if you want to work in defence (as I do), you can (with some difficulty) get security clearance. This is not possible with a (lesser) visa.
So, in conclusion "TAKE THE TEST!"
Best regards
Mr tyke