Good evening

I was wondering if it is possible to make a part that needs a split mould without the use of a curing oven. The latter is pretty much keeping me from trying prepregs as I can't use my domestic oven because I can't get a vacuum line in there and buying one isn't in the budget. Getting an old domestic oven just for this purpose where I can make a hole would be possible but I also don't really have the space for setting up a second oven...

My idea was to use a very slow curing hardener, i.e 210 or 300 minutes, and then hand lay up the carbon and epoxy inside the two parts before closing them and then add the vacuum bag and just wait until it's cured. I think the curing time would be plenty long enough but the big question is will the hand layup stick well enough to the mould so that it doesn't come loose in the process or how can it be made to stick well enough? Has anyone done this and can share some experiences?

Kind regards
Martin

are you experienced in hand laminating with vacuum bagging? If yes, give it a try. for myself, I would consider a resonator guitar body via hand lamination a difficult task. at least, if optic is critical. getting everything done without any distortions and with nice corners is not trivial.

again, for myself I would consider it a fairly easy part when using infusion. my recommendation for difficult multi part infusion: get some 2 component laquer, spray the mold surface,  let it set a bit, and place the first layer onto the still slightly tacky surface. the goal is to just hold it in place, not impregnating the cloth. trim the fabric to the mold flanges, put the mold pieces together, and continue the build up with spray tack. this method results in absolutely perfect finishes, and you part is already painted. if your layup takes to long, a slight laquer mist onto the surface your working on and everything is tacky again.
when joining the mold, you should use some silicone on the outer flange, but not that much, that it reaches the laminate, when your are pressing the molds together. additionally, you might use a whole bag around the mold (keep sure the mold surface ist smooth). some resin will flow around the mold flange, but usually not that much.
I made this part in a 5 piece mold with infusion in one shot. there is a 90° flange all around the outer corner

Well if you did that part you certainly know what you're talking about, nice work! Must be a Super 7 style bonnet isn't it?

No, I don't have experience doing that, just imagined the hand way would be easier but I may easily be wrong.

I hadn't heard about painting the mold first, thanks for sharing this idea! It's somehow like applying gelcoat so makes perfect sense. Do you tape off the flanges before painting?

Your shape is definitely much more complicated thatn what I'm trying to make but the advantage is that you can reach in better to finish the layup.