sheet foam 15 mm thick vac down on to csm

[powerabout]

And no voids because operator can ensure its all wetted out

[tunnels]

And no voids because operator can ensure its all wetted out

WRONG !!
You never heard of bridging ?? It is and can be a major problem !! be it either from glass fabrics laid incorrectly or The peel ply LAID incorrectly or combinations of both !PLUS the shrinkage of the excessive heat from the cooking resin and the layers pulling really tight and cause fabric separation ,Looks like delamination (which it is ) meters long in chines and the keel all way up the bow almost to the top !. And the opposite of what could have been voids that have filled with just resin and no glass ! These places are never seen because the are inside within the structure !
Infusion i could write a whole chapter on the subject alone and I have enough photos of pre release and mould separation to verify most everything !, even strange hollows that at the time were a complete mystery ! But later it was revealed how the happened ! any ideas how this could happen !! Its real simple the cause and could happen to anyone at any time on virtually anything
So new systems, new problems of a different sort and nothing is absolutely perfect or fool proof !!and any fool can do it !!

Oh and as for using less staff to do the same job I have never seen that work less staff taking longer or more staff taking less time BUT still equates to the same at the end ! And the hire and disposal of rubbish in jumbo bins all adds up and is all part of the job !
Thank goodness Silicone reusable liners are being used in some places !

[powerabout]

so safest method is infusion or manual?

[tunnels]

so safest method is infusion or manual?

Like all things its purely in the hands of the people doing the work! ,If there is little attention paid to the finer details of either method then you get what you get AND as a supervisor it on your head because that what you are there for !!
Me I never stand around picking my nose and just watching im in the middle of everything with an eagle eye , I know the guys I work with and there capabilities so the ones that are a little slack get the big flat areas and the guys that are more conscientious are the guys where I work !But I do the final check of the job from end to end and everything every where !!!. im still looking even as the job gels !Then I wash my gear and toss my gloves in the bin and go back and look again ! ALL AND EVERYONE is doing the same !!!, checking everything !There is no such thing as walking away outside for a smoke because if I catch you ,you don't come back ever !your gone bye bye , same with cell phones are totally banned from the workshop NO EXCEPTIONS don't even carry them in your pocket !!.
As the resin gels and begins to shrink there is tension being placed on the fibres and that's the point at which you have to pay extra special attention to what's going on !!
Read what's the very last statement on the bottom of my page !! That's where im at .
Taking workers and showing and training them Has paid dividends and made them more aware of what is going on around them all the time . Also knowing and understanding the capabilities of the products they have to use !
Do you know and understand everything about everything you use ??
In all fiberglass workshops I been the glass shop has changed and we work Glide time AND THAT is well worth looking into !! Think about it !!

[tunnels]

http://www.proboat.com/category/construction/

I have subscribed to Professional Boat builder magazine for a long time and had a couple of articles I have written published over the years !
Today I discovered there news section that for guys doing re-coreing and thinking of maybe doing vacuum bagging part 2 of this article is very interesting and brings home how careful even professional people that do Vacuum bagging full time have to be all the time ! So just when you think you know it all and have all the answers think again !