boat stuck in mould

PVA alone is quite sticky. Lot's of water, and some (quite some) force should release it. I like releasing from one end to the other, stern to bow. once it's loose you can just pull it out.

 

Time to take that hammer? The use of rubber hammer means you give moderate impacts on the boat surface where it's allready a bit loose. Water tranfers the impact as shock btw the surfaceses and releases them one millimeter at a time. No part breaking...
BR Teddy

 

Just as a thought, I wonder if some sort of vibrator would let it loose. No, not the girlfriend's, unless she's got one of those gigantic horse siz.....
Something like one of those that vibrate beds in motel rooms, or a concrete vibrator or any thing that could be fairly easily rigged up that wouldn't wreck the mold. Like an old throw away washing machine motor with a slightly out of balance pulley.

 

You are better off jumping up and down a bit in the boat+ mould. Hammers (even rubber ones) can create spider cracks in product or mould.

 

Whacker,

In the past I have made long thin strips of plastic 1/16" x 1" x 48" with the end sanded to a very narrow wedge shape (10 - 15%) .

I slid the plastic between the mold and the boat and gently poked the thin wedge at the adhered area while having an assistant pulled up on the loose opposite end.


Best of Luck


Allan

 

We live and learn !!

this is a new project ?????
Ok dont know how big the boat is but if you are able to get enough water in the mould i would say it will lift gently and just keep lifting intill it comes out . You have what is commonly now as a stick up and its gotta come out like it or not . Compressed air is one of the last things you need . Banging with a hammer is an absolute no no . The pull will tear the gel coat off the product and the mould but its easyer to prepair . If you hit with a hammer you will actually damage the structure of the mould and have a perminant damage of star cracks .
If you fill the mould with water between the two the lifting force is increadable . Just put a hose inbetween the boat and the mould turn on the water and go have a cup of tea or lunch !!Just about stack my life it will simply float out all by its self . Remember how much weight the boat will carry when its in the water 100% of the time a boat in a mould float and will never get any where near its actual water line and it will have floated out all by its self !!! . not banging and jumping or hitting or doing any other manner of dance is required use nature to help you !!.

Back peddle and discribe in great detail how you waxed the mould and what wax you used !!give with the details including the cloth you used and where did it come from and how many times has it been used !!.
Its a very bad and popular mis conception but you never actually build coats of wax as such !! And as for rubbing on a thick wax and thinking its better is another waste of time as well .
Get a soft sponge pad or make one !! wet the pad and wring the water out so it feels damp just then apply your wax and rub it in !! round and rouns and keep rubbing . if there is a smear thats all you need then carry on and allow to gas off then wipe over and polish and move on to the next and so on and so on !! always use new rags or rags that have been washed never pick up a rag thats just laying about !! unless you know where it came from personally dont touch it !! . cheese cloth is one of the best polishing materials and you can washing it many times .We used to have a cheese cloth manufacture close by and they would take all out dirty waxy cloth and rewash it for us the washed is a lot better than the new . What causes stick up ?? who knows !! there could be a hundred things that will cause it to happen !! its one of those mysteries of man . one thing no one seems to take into consideration or even gives a second thought to is the compatability of materials !!! not all waxes are compatable with the gelcoats and resins we use all the time . some work better than others . some people will sware by a certion product !another person will try using the same thing and you can have massive problems but the two people may not be using the same gel coats or catalysts !! gel times could be differant cure times could be differant even the lay up could be shrunk and released the artical who knows . theres a million variations and its impossible to ever learn all those variables!!, BUT i have found world wide where ever i have gone PVA is the common barrier between them all .It works and has never let me down ever on over 20 years !!
Places ive worked like newzealand , australia , japan , South Korea , Tahiti, and here in China . As long as its pva it works !! The trick is in the way its used !!in this case thin is best and if you can see it when its sprayed you have to much on !! so if you had PVA used you would not have had this problem !! find "A PVA Mess!" on this same place on Boat design and read !!and understand the method of using !!.

 

Last questions for the day ! discribe how you applied the gel coat, what percentage of catalyst ! and what were your gel times ??:?:

 

Idiot banging with a hammer is a no no
Agree with everything else you said
BR Teddy

 

Dont need to bang or shoving strips in the mould or what ever , Just float it out put the hose between the hull and mould and brace it so the mould wont move and let the water do its thing and let the boat float!!

 

Dont kee[ us in the dark !!

let us know what you are doing and how its going !! any more probelms post pictures if the mouls comes out !! good or bad ,pictures !!!!.

 

One trick I saw was a pipe and flange bonded to the mold down around the keel. Put water in the pipe and a tight fitting wooden piston in after, then hit the piston with a big hammer. This forces the water between the mold and hull and POP, out it comes

 

ok, its slowly killing me and im just starting to give up now, i left it hanging for two days no job. then heated where i though it was stuck no joy, ive tried 2 foot long wedges and pushing them down to the keel no joy. ive used a resorvoir of water pumping it in and taking it out no joy, the mould is now cracked at the very top of the stem from the pressure of the water. so today i though maybe its the keel thats jammed it. so ive cut the keel out of the boat now thinking it would be solved still no joy. im just starting to think the best thing to do is cut the boat out of the mould at this stage, this is day four and i dunno how much more is in me with it.
TR 104 High Temp Wax is the wax i used, 6 layers bran new cloths used, waxed the mould waited 10min for it to dry, buffed it off. waited half an hour for the wax to settle before starting the second wax and so on till all was done.

gel coat was two layers and 10 to 15 hours given before starting the second gel coat, and again before fiberglassing. 15ml of hardener for every liter of gel coat given. i did everything by the book and this is what i got for it. the first boat came out no problem so i cant understand now why i have this big mess on my hands now.

 

So it's 'glued' to the mold and not and undercut issue. All the mold has 'draw' or a slight taper to the hull so it's not stuck due to mechanical interference? This must be so since it worked before. But one possibility is the mold was a little too light and distorted from the first job, and now there is the problem of keel being bigger at bottom than top, just a millimeter? This would cause a mechanical jam and water etc will not help. Cutting the mold down the centerline with a small circular saw would divide the mold in half, easy to put back together, free the boat and reveal the problem.
Or dynamite and C4 mix, like Myth Busters.

 

yes ive seen some moulds that are split down the middle and have hinges, but what i cant understand is how dose this joint line not show up on the boat when its taken out of the mould. would it be a big job to split the mould in have and attach hinges.
ive tried bracing the mould and filling it up with water but got no where.
its a light mould alright its flexable at the gunnels all around when moving it. maybe this is the problem

 

Whacker


How big and how thick is your mold? Is it small enough that you could try filling the actual boat with water and then a ice (100 lbs?) to get the actual boat to contract and pop loose? Just a thought.



Can you post photos? Photos would probably help everyone understand the situation better .




Allan