just to start im going to explain my position at the minuet.
i am currently welding and have 2 years post apprenticeship experience, i understand i need 3 years experience before i can apply for a skilled migration visa.

i would like to come over as soon as possible and i know that the skilled migration visa usually takes around 8 months plus another 2 months for my qualifications to be checked.

if i was to come over to Australia on a WHV in the middle of 2015, could i still apply for a skilled migration visa while in the country as i will have 3 years experience in August 2015.

also are employers a bit reserved about taking on people with a WHV in welding due to the restricted working time of 6 months?

thanks in advance

Not sure about how employers react to the WHV, but for the skills assessment, you need to check that you can supply everything needed. If they are asking for 3 years experience, then it will be 3 years verifiable experience with references in a given format. Similarly, if it is for points, you will need to prove experience with references, pay slips, tax records, etc

If you need 3 years experience (and I do not know if that is the case but assume you are correct), then I would recommend staying put until you have got three years experience. Certainly seems like a much better plan than assuming you will fly in, find work in your field straight way, too up work experience and then apply in August.

Why shoot yourself in the foot for the sake of a few months? Australia isn't going anywhere.