Starting my build next week. (1 Viewer)

[WaveBreaker]

So after lurking and reading build threads for awhile i figure its time to start.
parts will arrive off and on over the next month.

A couple of things i have noticed everyone tends to use A LOT of steel thru out the whole building process. My self i wont be going this route.
As a Boat Builder by trade for almost 35 years i will use steel for my frame and base structure but for the Box portion of the trailer it will be composite.

As for using steel thru out i'm still puzzled by this one. Don't get me wrong you guys are building some great trailers here and your ideas and applications inspire me to build.

Simple math unless of course my long hand is out
ex: a 4x6 foot by 2 feet deep box built from steel. 1x1 say with a .120 wall for up rights (frame of box) and 14 gauge sheet metal. now this includes bottom,front/rear and flat lid. you need 80 feet of 1x1(1.43 lbs.per foot) , 88 sq. ft. sheet (3.125 lbs per sq.foot)
now here goes my math that weights out at 389.4 lbs.

this is just the box .

Now i can build this same box via composites exact same dimensions
structurally sound enough for what will be carried on top and inside for 170 lbs.

This is a weight savings of 219 lbs.
Unless i am missing something here that needs that much steel.
Is it perhaps related to longevity or damage?
or is it just the norm to build this way?
To me from a pulling perspective that's alot of weight.

But anyway i will take pictures as i go and post.

 

[rdsk8ter]

its mainly for damage how well will composite hold against rocks?

 

[WaveBreaker]

i guess depending on how hard you hit a rock.. a glancing blow will perhaps damage the surface layer. possibly do internal structure damage but hard to say. im used to building boats not trailers

here is an example for you for strength.

Back in the 80's while composites were not really what they are to day i was asked to build two Hydro's now these were basically 4 feet wide 8 feet long shaped like a wedge. like a sheet of plywood with a motor strapped to them.

we powered these with 20 horse outboards.
they would do flat out about 40 miles an hour. did not turn worth a damn but went great straight. The substrate was 1/4 inch plywood with a single layer of 1.5 oz fiberglass mat. one of the guys lost it in a turn and hit a pylon (telephone pole size) almost dead center.. he went flying with steering wheel clutched in hand. the boat was still floating. we rescued him and pulled boat from the water. he was fine other than being shook up, now the hydro looked from the outside perfect except for a half-moon dent in the front from the pole.. but every-frame with in was cracked. i'm not a math guy really but take in to account here... 1 guy 180 lbs.. boat about 100 lbs..motor 80 lbs hitting the pole at 40 mph.. that is a lot of force. if you hit a rock that hard all i can say is ouch..


the box itself will be protected from side blows for the most part by fenders etc.

 

[rdsk8ter]

true that was he ok? I bet youll be ok for thew most part but a pole is a long blow not a small blow try it maybe your a pioneer here on that

 

[WaveBreaker]

yea he was fine other than a bruised knee from taking out the steering wheel.

Any way i made a start..