Anyone have any tips on how to remove those mold that are stuck on pretty good? Before actually making the mould I waxed my plug with some release agent wax i got from a local fibreglass store and they I wiped on some release agent, well what seemed to me was enough obviously wasnt and now im having a hard time removing the damn thing. Any tips on how I can remove this stuck on mold?
Sounds like you have a negative. Or a very sharp angled mold.
Use a rubber hammer. Hit the sharp edges first. Then hit he flat sides of the mold second. After that hammer plastic wedges under all corners (that will give it equal pressure on all corners). Then use a pry bar (if possilbe) under a single corner. Wrap it in a towel to avoid damaging the mold.
Use PVA in addition to wax next time. Unless your molds are ungodly pollished.
Actually my mold is a very positive one. I did use PVA release agent AND wax but I guess I didnt use enough of either PVA/wax and now its stuck like hell.
I’ll give the rubber hammer idea a go, sounds reasonable enough to me. I’ll just try a wrapped towel in with a screw driver as a pry bar would be impossible due to its small size. BTW what kind of plastic wedges are we talking about?
Also try pouring some water inbetween the mold & plug and then hitting it to hydrualic it off.
Sometime heat helps too. Even compressed air too…I have seen a whole car with a 1 piece mold on it: they drill a little hole thru the top and blew it off as it was for the Score off road stadium body molds from a brand new car model!:eek:
Was the PVA still wet or how long did you let it dry? Was the green in color from the PVA?
The plastic (PE) wedges are available at every composites suppliers and resist scratching the mold or parts.
Hmm water idea doesnt sound bad either, I was thinking about that but though it wouldnt really help… Heat doesnt sound bad either but does that really help that much??
I left the PVA for about 10-15 min, it was dry to the touch by then so I decided to put on the gelcoat then.
Any other place that sell stuff similar to these wedges? The fibreglass store owner has gone out for a while and I dont think he will be back until a weeks time 
BTW I was planning on leaving/soaking it in really hot water for a while to maybe loosen it up, will this be ok?
Water will dissolve the PVA to help break the seal.
PVA needs more than 10 to 15 minutes to fully dry before gel coating.
Definitely helps that much. Its a similar theory to heating up pistons to intall the pins.
If Im having a serious problem with a mold. My last resort is heat. I really dont like using it because I dont want to destort the part.
The way I do it is to hit wedges into all the corners then set the mold under a portable heat lamp…then walk a way.
Come back in 20 minutes and it will either be popped off on its own, or, one or two prys and it will fly off.
I had this happen in the begining of my molding experiences. It was cold and I got impatient and I put my mold next to the propane heater.
The gelcoat and first layer stuck to my mold like crazy. I busted most of the part out and the pieces left I had to try to chisel out with a screwdriver.
Fortunately those molds sucked anyways so I tossed them.
Why oh why does anyone use PVA?? Never ever had a problem using wax only, but it must be applied carefully, and a new mould needs several coats.
What wax do you use?
I use PVA at work. For home use its not so practical though.
Dunno Ive never used PVA
I hate the texture it leaves on a part.
I would like to use it for open gelcoat curing though. Say patching a boat hull. Spray some pva over it and it will cure!
Gel coat patch repair will also cure if you add a little wax to the final gel coat, which is far easier than messing around with PVA.
So, SIFU (the orginal poster) did you get it off ok or not?
Myself, I like semi pernament mold release with wax too!