MORE TRI CABIN TRIVIA, CONSTRUCTION....

aaronbocknek · Post by **aaronbocknek** » Wed Feb 01, 2012 1:33 pm

thought you guys would appreciate this from the boating article from 1971. don't think much changed in the course of the layup, but, this is how the tri cabin (and i'm assuming other trojans) were constructed......

molded fiberglass hull and deck/deckhouse. hand layup of chopped strand and 'fabmat'. 4 ply hull bottom---basic thickness .371" (1 ply 1.5oz chopped strand & 3 of 24/15 fabmat).
3 ply topsides---average thickness .228" (1 ply chopped strand and 2 of fabmat).

hull reinforced in way of keel with 2 plies of fabmat from forefoot to transom plus 3 plies fabmat from stem head to transom. hull thickness in keel area varies from .492'' to .756''. chine reinforced with 3 plies of fabmat from stem to transom. longitudinals of doubled 3/4'' marine plywood encapsulated with 2 plies of fabmat which is lapped between chine and outboard stringer, between stringers, and between inboard stringer and keel. minimum bottom thickness of hull is .492''.

**FABMAT is a controlled deposit of chopped glass fibers chemically bonded to a layer of woven roving. this material eliminates the need for applying alternate layers of mat and roving, and offers good tensile strength and resistance to delamination. it also saves time in cutting, handling and wet-out. it absorbs less resin than equivalent mat and roving laminations layed up separately. the 24/15 code for fabmat indicates a combination of 24oz woven roving and 1.5oz mat.

there you have it folks.... trojan layup 101. hope you found this as fascinating as i have. at least it gives some insight to how these vessels were constructed. they do not go into the ins and outs of the gelcoat, but, from what i understand, trojan gelcoat had a really high zinc content which is why, to this day, they polish up and retain their shine better than new construction.
enjoy.
aaron

k9th · Post by **k9th** » Wed Feb 01, 2012 5:27 pm

Thanks Aaron - great info

prowlersfish · Post by **prowlersfish** » Wed Feb 01, 2012 6:24 pm

Interesting

aaronbocknek · Post by **aaronbocknek** » Wed Feb 01, 2012 6:27 pm

like i've said before, trojan did some great things in their time,then again, they goofed up with some things too, but, it's probably like that with other manufacturers for the time.
aaron

prowlersfish · Post by **prowlersfish** » Wed Feb 01, 2012 6:50 pm

where did you find this info ?

aaronbocknek · Post by **aaronbocknek** » Wed Feb 01, 2012 7:03 pm

prowlersfish wrote:where did you find this info ?

from the article on the 'new' all fiberglass tri cabin boat test from my vintage 1971 boating magazine. not only is this info included, but, so are measurements, power curves etc.... the original tri cabin even had a choice of mercruiser or chryslers. to be honest, i never even knew that the original tri cabin had a choice of engines. mercruiser 270's (350cu) or chrysler 280's (383cu).
aaron