In VIP, vacuum infusion process, i see almost everyone places the resin supply bucket lower than the mold. Would it speed up the infusion if the bucket were above the mold?
Were only talking about 12 to 24 ounces of resin here.
This is done so that the resin is sucked in the laminate due to vacuum and not gravity. If the resin bucket is above the laminate there is the chance to suck air.
The infusion speed is dependant on the flow through the laminate not flow into the bag (to a point). Give it a go lifting the bucket on your next infusion at the start. You will have a “bubble” of resin form, lower the bucket and it will suck back down.
Siphon effect. While you can raise the bucket above the part in the start, it will flood your part, but you have to remember to lower it near completion. Else the resin will just dump itself into the part, and you will be resin rich like crazy!!! Also, if you “dump” the resin into the part, you might not allow the air in the tows to escape, causing voids and surface issues.
Makes sense about flooding the part with resin. We don’t want that. Thank you guys!
It’s actually not a siphon effect which is liquid moving to a higher point to get to a lower one. Raising the bucket makes it easier for the for the resin to flow through the laminate by removing one of the impediments of fluid flow. Instead of fighting gravity the resin is aided by gravity.
isn’t that what siphon effect is? Effective gravity pushing the liquid from a higher point to a lower?
Raising the bucket over the height of infusion basically feeds the resin under pressure. This is fine on hard closed tooling because it forces resin through the laminate. On soft b-side tooling, AKA a vacuum bag, it inflates the bag and causes resin to flow over the ply stack. This creates the illusion of faster flow, but that doesn’t mean the part is being saturated. Lots of air pockets air trapped in the part even when the bucket is brough down below the lowest point of the tooling surface.
Always remember that resin takes the path of least resistance. That resistance needs to be the ply stack.
Almost. Fluids like to stay at their lowest energy state, which usually is the closest they can get to the ground. Siphoning is a phenomenon where fluid temporarily flows upward to get to a lower state. So it is a siphon if the inlet tub goes over the top of the bucket but not if its a fuket and the tube is at the bottom
Oh lordy…forgot about that small detail, of the tube actually going UP 