Total mold thickness

[JohnMc]

I'm familiar with stitch & glue construction, but I'm considering these current plans I own for this modern lifting keel 18' racing sailboat (Stitch & Glue) I am considering building it in a female mold so I can have a very high quality finish: gel-coat, solid fiberglass - My question is the female mold construction.
I understand the frame dimensions I have currently. I will have to subtract the thickness of the plywood used first. But approximately how thick will all the rest add up to, ie: fiberglass, primers, tooling gel-goat? I'm trying to see how much to deduct from these frame plans to make it a female frame plan and still hold the plan dimensions.
Make any sense?
Thanks for any help
JohnMc
18' Racing Sailboat

[Pericles]

Good start, http://www.devlinboat.com/order.htm The finished boat will be lighter and cost much less that building a female mould for a one off.

Pericles

[JohnMc]

Pericles, thanks for the reply-what your saying then is that if I'm not going to make more then one hull to stick with the fiberglass over wood painted exterior, as it is? To much trouble building a female mold for one boat? how would you every get the gel-coat/eggshell type finish without a female mold? Or I guess you could use a very good paint and workkkkk it.
If I wanted to sell the boat new and hope for some other orders I would want to go gel-coat, don't you think?
JohnMc
Racing 18' sailboat

[Pericles]

Not necessarily. http://duckworksmagazine.com/03/r/ar...ass/bottom.htm

It does work. I used it.

Here's a paint system.

http://www.yachtpaint.com/usa/

A finished boat.

http://www.yachtworld.com/leaving_yw...w.vicemusa.com

Pericles

[JohnMc]

OK - Sold me - stitch and glue using 1/4" Okum1088 ply and 2 layers cloth. Thanks for that tip on the plastic film. I'll also use that paint system.
Lets get this boat going!!
Thanks
JohnMc
I'm currently casting/building the 400lb. lead keel bulb using the lost foam method. Ever heard of this? I'm collecting old tire weights to melt down. (I will buy quality lead! to slow to collect by hand) I Have made my pattern in Styrofoam and will pack moist sand around to pour.
I have had some others interested in this - (I my be taking orders soon to cast other bulbs for builders!) I've had a couple inquires for casting lead bulbs, so if anyone else is interested please let me know, as I am currently pricing quality lead blocks for production. (A lot easier then finding it myself.) I will set up a foundry type shop!
Any other interested in having a lead bulb produced for them ,again contact me so I can price quantity. Thanks
I first need to see how much interest I have in casting sailboat bulbs and keels.

[SamSam]

Originally Posted by JohnMc

I'm currently casting/building the 400lb. lead keel bulb using the lost foam method. I Have made my pattern in Styrofoam and will pack moist sand around to pour.

I'm sort of curious as to how you got a "reputation" of -1 so quickly?!?

Other than the extremely toxic fumes from melted lead, the second caution I've always heard was that moisture and melted lead created explosive steam that tended to splatter the lead all over the place. You apparently let the sand dry first? Do you add something to it, like glue, so it will keep it's shape?

[JohnMc]

What does -1 mean anyway
In the "general discussion" area please find a post where I have already apologized for the many "Keel" postings I posted, Sorry, I get excited over this boat building stuff. If this is what your referring to -then - there you go

There are a number of things that they use to "hold" the sand together, a lot of good info on the web about casting!
JohnMc
SB18

[Gerald]

If I understand your original statement you wanted to build a plug and then a female mold so you could have a gel coat finish???? Build your boat and spray it with gel coat. Add some paraffin so that you can sand it. The information is available on the net if you do a couple of searches.
Good luck
Gerald