The Birth of a Race Boat
#51
Registered
[QUOTE=glassdave;2972187]Autoclaves work on positive pressure not vacuum. When combined with a vacuum bagged laminate the part is first layed up, completely bagged and vac'ed of any air voids then placed in the autoclave and kept under full vac pressure until the autoclave reaches its peak positive pressure or vented to the outside atmosphere. When pressure is applied the process kind of works in reverse of the original vac bagging. If that makes any sense
Also think of this. How would you heat it if it were a vacuum?
that a cool website on the 787 by the way. Its amazing the fuselage parts are built all around the world then brought together in WA. Thanks.
Dave,
A few years back we used autoclaves to laminate printed circuit boards used in all elecronics euipment.
we would use C stage core material(cured) with the copper circuits on it and bond them together using B stage pre-preg sheets.
We would lay them up in steel fixture plates to maintain registration of all the layers and then vacuum bag them and then put many of these fixtures iinto the autoclave and pull vacuum and then heat CO2 or nitrogen to about about 350F to make the pre-preg flow and cure. we also also post bake the boards in a std oven for final cure
This was just a simple version of what we did.
One of the advantage of the autoclave for us was that we could laminate different size fixtures in the same press load.
but the autoclaves never really caught on with the PC industry
Prior to Autoclaves and today we use a vacuum assisted Hyd press using heat and pressure to laminate the PC together.
Sorry running off at the fingers
Thank you
Jim
Also think of this. How would you heat it if it were a vacuum?
that a cool website on the 787 by the way. Its amazing the fuselage parts are built all around the world then brought together in WA. Thanks.
Dave,
A few years back we used autoclaves to laminate printed circuit boards used in all elecronics euipment.
we would use C stage core material(cured) with the copper circuits on it and bond them together using B stage pre-preg sheets.
We would lay them up in steel fixture plates to maintain registration of all the layers and then vacuum bag them and then put many of these fixtures iinto the autoclave and pull vacuum and then heat CO2 or nitrogen to about about 350F to make the pre-preg flow and cure. we also also post bake the boards in a std oven for final cure
This was just a simple version of what we did.
One of the advantage of the autoclave for us was that we could laminate different size fixtures in the same press load.
but the autoclaves never really caught on with the PC industry
Prior to Autoclaves and today we use a vacuum assisted Hyd press using heat and pressure to laminate the PC together.
Sorry running off at the fingers
Thank you
Jim
Last edited by dammmagnum; 10-13-2009 at 05:19 PM.
#52
I've heard of some inert gasses being used in other industrial autoclave processes for the pressure side. Theres all kinda uses for these things.
__________________
Throttles- Cleveland Construction 377 Talon
08 OPA Class 1 National Champion
08 Class 1 Geico Triple Crown Champion
08 OPA High Points Champion
10 OPA Class 1 National Champion ( happy now Ed! )
Throttles- Cleveland Construction 377 Talon
08 OPA Class 1 National Champion
08 Class 1 Geico Triple Crown Champion
08 OPA High Points Champion
10 OPA Class 1 National Champion ( happy now Ed! )
#54
Registered
Yes, we used either CO2 or Nitrogen
which was a pain as we had to have large storage tanks, plus both CO2 and Nitrogen are super cold and then have to heat them using a electric heating element to 350F,, the heat rise was fairly slow
Thank you
jim
#60
Platinum Member
Platinum Member
Thread Starter
Laminating the rest of the stringers, that solid sheet is ready to be cut up for bulkheads, and finally Joe checking out the progress.