Vacuum bagging a fin can -- prep?

[dixontj93060]

I have all the materials and have my plan in place, the one area where I would like some input though is how do you / should you prep the aft airframe opening. It needs to be sealed to pull the vacuum, but you don't want to epoxy it shut in the process. What techniques/pieces/parts have you experienced vacuum bagger's used to accomplish this?

 

[daveyfire]

I have all the materials and have my plan in place, the one area where I would like some input though is how do you / should you prep the aft airframe opening. It needs to be sealed to pull the vacuum, but you don't want to epoxy it shut in the process. What techniques/pieces/parts have you experienced vacuum bagger's used to accomplish this?

Not sure if this will work with your design or not, but I usually seal the bag to the airframe with a ring of bag seal tape just aft and just forward of the fins.

If the fins are flush with the aft end of the airframe, I have bagged to a motor case before; I leave the case sticking out the front of the airframe and either extend the bag forward onto it, or pack a bunch of bag seal tape into the gap between the case and the airframe to seal it.

I'll try and find some pics when I get back to my computer. (I owe another user some also, so this is good motivation.)

 

[dixontj93060]

What equipment are you using? I was considering vacuum bagging a fin can with CF layup, and am trying to decide about a pump, fittings, switch, and whether to use vacuum bags from a supplier with sealant tape or use a large clear trash bag.

If you bagged it already how'd it go?

Haven't done it yet. It is tied to completing my curing oven here. Materials-wise, I purchased nearly everything from ACP Composites especially since I needed vacuum sheets and seals that were high temp. For the pump, I am using the pump I have for propellant processing originally purchased at Harbor Freight (similar to this one).