making a cowl

[rpmjunkee]

Ok,I've decided to make a cowl for the jae rigger I'm building.I think I understand how to do it as far as making a plug and laying on the fiberglass or carbon fiber cloth.I'm just not sure as to what to use for a mold release agent.I know mold release is made,but I was hoping to be able to use something I already have around the house to keep the cost down.Will vaseline work?I just don't want to ruin a good mold after spending the time to make it. I'm sorry if this has been covered by someone before,but I haven't seen anything on it.Thanx Bill Carroll.

 

[dave roach]

Bill

I use pva in my mold you can brush it in or spray it.The best is to spray it.

Dave Roach

 

[Bert Dygert]

Bill,

The mold need to be seasoned. The bestway to do this is to apply a thin layer of Johnson pastewax or PVA paste wax onto the mold. Let it haze over and almost dry. Then with a clean rag buff cavity really well. Let the mold set overnight and them repeat this process of waxing and buffing for three time. Let the mold set overnight buff again. Then apply PVA like Dave said.

This should protect the mold and give you good release.

Bert Dygert

 

[Bill Gibson]

Bill,

The mold need to be seasoned. The bestway to do this is to apply a thin layer of Johnson pastewax or PVA paste wax onto the mold. Let it haze over and almost dry. Then with a clean rag buff cavity really well. Let the mold set overnight and them repeat this process of waxing and buffing for three time. Let the mold set overnight buff again. Then apply PVA like Dave said.

This should protect the mold and give you good release.

Bert Dygert

YEP! Thats the way to do it right there! Almost garuantees a clean separation....If the part gets difficult ive even dunked it in water as the water dissolves the PVA...the part just seperates from the mold...no pullin or tuggin and risking the posibility of damaging the mold!

 

[rpmjunkee]

Bill,

The mold need to be seasoned. The bestway to do this is to apply a thin layer of Johnson pastewax or PVA paste wax onto the mold. Let it haze over and almost dry. Then with a clean rag buff cavity really well. Let the mold set overnight and them repeat this process of waxing and buffing for three time. Let the mold set overnight buff again. Then apply PVA like Dave said.

This should protect the mold and give you good release.

Bert Dygert

YEP! Thats the way to do it right there! Almost garuantees a clean separation....If the part gets difficult ive even dunked it in water as the water dissolves the PVA...the part just seperates from the mold...no pullin or tuggin and risking the posibility of damaging the mold!

 

[rpmjunkee]

Thanx everyone.I'm going to give this a try.It will be fun to put something on the boat that came from me.Maybe all the shapes that have been in my brain will go away if I just make one!Bill Carroll

 

[steve wood]

you don't have to wait overnight for the wax to dry. put on 5 or 6 coats,let dry between coats,5 minutes or so. you must use pva also. brush or spray. let dry well.then build up your mold from polyester resin and glass cloth. start with a couple layers of resin, then add strips of cloth,and resin.then you can use some mat, till you get a mold about 3/16 thick. after you pull the mold from the plug, repeat the wax and pva to the mold befor you lay up your cowl. once the cowl has dried(i use west systems epoxy, and dry under light bulbs for at least 8 hours) you can blow the epoxy cowl out of the mold with an air hose. just hang on to everything. if you use the polester resin for your mold, that you buy locally, it will have wax in it that rises to the surface when it dries, and you will have to sand between coats for the next coat to adhere properly

 

[rpmjunkee]

you don't have to wait overnight for the wax to dry. put on 5 or 6 coats,let dry between coats,5 minutes or so. you must use pva also. brush or spray. let dry well.then build up your mold from polyester resin and glass cloth. start with a couple layers of resin, then add strips of cloth,and resin.then you can use some mat, till you get a mold about 3/16 thick. after you pull the mold from the plug, repeat the wax and pva to the mold befor you lay up your cowl. once the cowl has dried(i use west systems epoxy, and dry under light bulbs for at least 8 hours) you can blow the epoxy cowl out of the mold with an air hose. just hang on to everything. if you use the polester resin for your mold, that you buy locally, it will have wax in it that rises to the surface when it dries, and you will have to sand between coats for the next coat to adhere properly

Thank you,this should go much better now that I have the process right in front of me.I can see now that I probably would have made a mistake or two along the way.I'm confident I can make one now.Pray for spring.....Bill.