Construction Project help

Betonov · 02-01-12, 06:31 PM

This thread needs a profesional boatbuilder

what I would do is create a styrofoam model, about 3 mm smaller in any dimension. Styrofoam is lightweight and easy to sand into shape (use very fine paper, 220 would be the coarsest, anything more would take chunks out of the styrofoam. T
hen take your fiberglass sheets and epoxy resin and just carefully and with love completely cover every centimeter of the model. Evenly is the name of the game, you dont want balls of dried up fiberglass plastic stuck all around the model. Sanding that away is the worst experience in your life
When the resin has dried you have two options:

a) leave the stryofoam core as it is
b) drill a small hole and pour in acetone, it will dissolve the styrofoam leaving you with a hollow toy. (3 layers of fiberglass would be a minimun here)

Then get yourself some modeling putty, any car repair store should have it. Evenly cover every centimeter of the model with it, about 2mm thick.
After that, just sand baby sand, 100 coarse should do it. Sand until you have nice flat surfaces and radius making your model ooooohh so sexy.
Then get yourself some sprayputty and spray it on the surface. Many thin layers as opposed to one thick, remember children, you don't want drops forming.
After that, let's do some more sanding

220 coarse, 500 coarse, 1200 with water, 2500 with water. After that you have a surface smooother than the mirror in your bathroom.
Color should be applied after the 220 sanding. And also, many thin layers, and I do mean many, if you oversand it you'll get the sprayputty showing in very ugly patches trough the color.

Pro's: lightweight, durable, waterproof, lasts about 4000 years, looks gooood

Con's: not for impatient people, delicate work, necesary precision may kill you, chemicals, one core model for only one ship, sanding is a (favourite foul word)

The above desrcibed method is going to be used to create a model for a sailboat (model) hull. The only difference being that I will use it as a mould for the mould.

FYI: 220, 1200, 2500 are numbers which describe the coarsnes of the sandaper, aka grit size
http://en.wikipedia.org/wiki/Sandpaper#Grit_sizes

02-01-12, 06:31 PM	#16
Betonov Navy Seal Join Date: May 2009 Location: Slovenia Posts: 8,647 Downloads: 26 Uploads: 0	This thread needs a profesional boatbuilder what I would do is create a styrofoam model, about 3 mm smaller in any dimension. Styrofoam is lightweight and easy to sand into shape (use very fine paper, 220 would be the coarsest, anything more would take chunks out of the styrofoam. T hen take your fiberglass sheets and epoxy resin and just carefully and with love completely cover every centimeter of the model. Evenly is the name of the game, you dont want balls of dried up fiberglass plastic stuck all around the model. Sanding that away is the worst experience in your life When the resin has dried you have two options: a) leave the stryofoam core as it is b) drill a small hole and pour in acetone, it will dissolve the styrofoam leaving you with a hollow toy. (3 layers of fiberglass would be a minimun here) Then get yourself some modeling putty, any car repair store should have it. Evenly cover every centimeter of the model with it, about 2mm thick. After that, just sand baby sand, 100 coarse should do it. Sand until you have nice flat surfaces and radius making your model ooooohh so sexy. Then get yourself some sprayputty and spray it on the surface. Many thin layers as opposed to one thick, remember children, you don't want drops forming. After that, let's do some more sanding 220 coarse, 500 coarse, 1200 with water, 2500 with water. After that you have a surface smooother than the mirror in your bathroom. Color should be applied after the 220 sanding. And also, many thin layers, and I do mean many, if you oversand it you'll get the sprayputty showing in very ugly patches trough the color. Pro's: lightweight, durable, waterproof, lasts about 4000 years, looks gooood Con's: not for impatient people, delicate work, necesary precision may kill you, chemicals, one core model for only one ship, sanding is a (favourite foul word) The above desrcibed method is going to be used to create a model for a sailboat (model) hull. The only difference being that I will use it as a mould for the mould. FYI: 220, 1200, 2500 are numbers which describe the coarsnes of the sandaper, aka grit size http://en.wikipedia.org/wiki/Sandpaper#Grit_sizes