Re: boat building materials.....
Kenny... this was written in a pm to you... but apparently my message was to long for a PM... and i was asked to shorten it.... instead i just posted my reply to your PM here.
Hey Kenny,
Welcome to Iboats.
Well.... you asked the 64 thousand dollar question with that one.
It's all about compromise.
How much do you want to spend... and how long do you want it to last? is the question.
There is a mountain of information out there and try not to read into any 1 thing to much. There is no universal answer to anything.
What ever wood you choose to use will work. It's just a question of for how long.
You can hollow out a pumpkin and it will float. You can hollow out a giant pumpkin and jump inside of it.... it will still float.
Alot of brand new boats out there advertise "no wood" as a selling feature. No wood means no rot right???
Well, wood, whatever species, has a lot of beneficial properties to boat construction. Way to many to list... and i'm sure i do not know them all anyways.
In most boats, its actually advantages to use wood here and there.
We've been doing wood for 2000+ years.... and glass for the last 60.
In your note... you said
kennyboater said:
if i do not have to spend the time and money glassing
Try and get that out of your head... boats cost money, even if your doing the work yourself and getting material at wholesale. Whatever figure you have in your head at this moment... double it if you want the boat to last for a few years.. triple it if you want it to last a long time.
If you do the boat in rough pine... but your a hell of a fiberglasser.... the wood will never be exposed and will last forever. If you use Mahogany, and are a half assed glasser... it will still last a long time because mahogany is a good base wood that resists water and rot naturally. If you use pine and can't glass to save your life... it will last maybe a year. If you use PT throughout... and you don't glass... maybe 3-5 years. If you use PT and glass the best you can maybe 5-7. Again it all depends on how dry your boat stays on the inside. Do you leave it out uncovered in the rain... or is it garaged all the time. is it on a salt water mooring, or a freshwater dock.
By design... PT wood (ply or rough stock) is made to resist penetration by everything... including water. For years people use oil based stains and varnishes because oil does not mix with water, it repels it.
It's all about how deep you can work oil into the wood.
Working oil into the wood takes time... and time is money. So the next best thing is how to seal it instead. Polymer varnishes and fiberglasses work best for this.
Even marine grade varnish... expect to apply at least 7 coats to the final product. and expect to sand and re-apply once every couple of years.
PT mechanically infuses the wood with oils and anti rot, anti fungus agents. What would take you 50 coats by hand... can be bought by buying PT wood.
If you look at pine as a wood. Its very poreus... but also very sappy. If you kiln dried it and got the sap out it's still very poreus. Its is going to suck up anything like a sponge.... be it water or varnish or glass. Pine dampens vibrations well but isn't a notably strong wood.
If you take mahogany.... its not as poreus and has no natural sap. It will not absorb water easily... but it will not absorb glass easily either. Glass will still stick and bond to mahogany if high quality glass is used by an experienced glasser. (needs to be thinned). Mahogany has good strength and vibration properties.
PT.... well... it resists glass. and it resists water... and about any other thing you can pour on it... but... it only resists it for so long. then the wood will give and start to rot. You can glass over it.. but it's more like a band aide on an open wound... instead of stiches. Glass will stick to PT if the wood is roughed up like crazy. But glass will not bond to PT, it will not penetrate PT enough to become one with it. Even with a great glass job, because boats flex under use, the glass will eventually start to peel away off of the wood.
If you are gonna ask me what i'd do... don't. Because what i do is a decision based on compromise between me an my customer.
But.... if money were no object... and i glass like a madman... i'd do mahogany and epoxy resin all the way.
Hope this helps!!
Cheers!
Jason
