Thanks for the replies
OK,I understand that the ideal is a vacuum pump.Actualy,its what Im using now.I have an ole vacuum pump,that works.But I use it in my studio for degassing mostly silicone and some resins.Its a must for my daily job,and degassing only requires some minutes work for the pump in my case,and I dont like having it on for long periods.
So,the next purchase will be a dedicated pump for Cbf,as recomended above.Also,now we are playing around with small parts,but who knows what will come after.For what I read the venturi might be a bit on the short side I guess.
Thanks for claifying.

A vacuum pump will produce better vacuum and for longer.  A venturi doesn't pull deep vacuum  like only 25 inches of HG (i am american .8ish bar I know we use a horrible system)  They also cannot be used for long duration of time like pulling vacuum overnight. IMHO Pay a little more and get a dedicated vacuum pump.   

and they can be quite noisy

A Venturi will not produce the required vacuum, and is impractical to use for the hours needed

Hi,posted this on the general composites...thought it might suit better here.

Hi
Id like to know what are the main differences between using a venturi vacuum system and a pump sistem.
Purchasing a venturi one seems cheaper(already have a good compresor),but Id like to know what is the downside if there is,and its limits.
We are focusing on small bycicle parts,no infusion.
Thanks in advance.