Boat Won't Release


My first hull won’t release from the plug I made. Is there any way to salvage the situation? Ideally, I’d like not to sacrifice my plug

I put a ton of coats of cleaner wax on the plug, but for some reason my boat is still sticking, and doesn’t want to release. Any suggestions for the first-time boat builder.


You could try compresed air if you have a small opening at an edge.
You could also try heating the hull with a heat gun to soften the epoxy, it will probably damage the hull though.

I had some problems as well but I used a piece of windsurfer batten and just slid it between hull and plug. Make sure that the hull has not bonded anywhere you did not wax?

With all that wax, it should eventually separate (assuming there’s no undercut on the plug anywhere). But if not, I think robert is on the right track with the air and plan B, but not to soften the epoxy. If you can get the hull warm and the plug cold, I believe the expanision/contraction will cause them to separate. Temps don’t have to be extreme.


I keep a “ton” of popsicle sticks laying around (collect during the summer) and then use a belt sander to sand down to ultra thin thickness wedge. Be sure to round edges and work down between the hull and mold. Easiest for me is starting along widest part of beam, although some work aft from the bow. After inspection, most of mine were stuck at the bow where the stem curves into the keel. Usually hard to get wax into the fine pointy part. Many leave that area flat so the can glue bow bumper there and then shape to a point.

Yar touches on an often found design problem where there is an undercut which really adds to frustration and demolition in some cases. An example is where the sides of a hull are narrower at the deck than the waterline. With the boat being wider at the waterline, you probably will need to cut it from the mold - there is no way to shrink it, unfortunately. The compressed air I’ve never tried - but sounds like a good idea - keep pressure low and perhaps work hull with one of my suggested popsicle sticks to loosen and allow air between mold and hull.

Try easing the moulding away from the mould and trickle some warm soapy water into the gap. The hull may then ‘float’ out. This is done in full size moulding shops.


Another trick that may work is to use the garden hose, wedged into a gap around the centre deck line of the hull The high pressure usually pops it out
Tony F

Thnx guys I just learned a ton. I always have to stuggle to get mine out.

I’ll second that. thanks A ton as well. In the past week, I’ve learned a lot from this forum. Hopefully people can be more active on it.

I thought I would be doing something wrong by trying to pry the boat loose. So, now I’m using a thin hacksaw blade and sliding it between the boat and mould.

It’s going so well, that I’ve had the wonderful opportunity to be demoted to Hello Kitty bandaid stature (don’t use a hacksaw blade, dummie!)

In my past profession I had been apart of some composite work over the years. The coolest thing I had seen was an air fitting tapped into molds to pull vacuum, that same fitting can have regulated low pressure air applied to it to aid in mold release. might work for some in the future, ymmv

Next time, after waxing, spray a couple of coats of PVA mold release onto the mold. It worked great for me when I popped out my first IOM hull.

I’m absolutely going to… This attempt is not too enjoyable. I had no Idea what I was getting into. Anything that releases easier in the future will be welcomed!

I was perusing this page:,%20Mold%20Releases%20and%20Clips-152.html

Some interesting things for when the next boat pops-off, including the “Air Injected Wedge”

what you could try . is this. if you used wax. use heat gun. but be very carefull and heat the edge. when you get a seperation line. pour hot water and gently push in the pop sticks and the more you pour . the more your should seperate