Time to build a trailer, got structural advice?

I've been tripping over a set of 5Klb axles that I widened a few years ago for a different project and just scored 2 16 foot lengths of 2x5 x1/4inch box tubing...for the sake of hauling it off for a lady...so seems to be a good start to building a trailer. I'll wind up getting some more 2x5 to finish the perimeter frame, but have a question about the crossmembers.

In my shop I have several lengths of 2.5 x 2.5 x .188 ornamental box tubing (not structural) I was going to use to add on to my shop some day, but figured I'd put a few pieces to use as crossmembers placing them at 2 foot intervals.

Primary use of the trailer will be (ofcourse) to scavenge old heaps and save them from destrauction, but will occaisionally want to move my tractor with it as well...the tractor weight is roughly 7500lbs.

I know the 2x5 perimeter will definitely be stout enough, but how about the .188 2.5x2.5 ornamental box tubing for the crossmembers?

2nd question is I've been told that a trailer should run about 5% for tounge weight...is this pretty accurate?

If Pop's was still around, I wouldn't have to ask these questions...so now I have to turn to the HAMB

Thanks.

 

Talking about "trailers" on this forum will apparently get your thread erased.

 

Heck, there's like a dozen go-kart and mini-bike threads...least I can haul my '36 on a trailer

 

10 percent tongue weight is the guideline I have always heard.

 

Have you seen the P.O.S. trailers running up and down the road? You are off to a way better start than some companies that build trailers for a living. Just for grins and giggles make the tongue out of some P/U frame rails. For that old fashion, ever desirable redneck look.

 

Put the front axle on the deck's center and you should be fine. There's actually a couple of really good trailer threads if you search.

I'd want heavier crossbeams and then use the thin stuff to spiderweb it for deck support. Corner to corner strength is real important to good road manners when loaded hard. good luck

 

My only concern would be the if the ornamental tube had sharp outside edges.(or less than ideal weld seam joints) Real stress concentrators, if so. 3/16ths is a reasonable wall thickness, but if you are using 1/4 in, then guess which ones get the peak stress levels? (The sharpies)

 

Thanks guys, the ornamental tubing does have sharp corners, ofcourse I have no way to verify the weld seams in it, seems like the best route to go would be to get some structural tubing for the crossmembers.

 

Concerning the axle locations.....All the info I found when building mine was that the axle centerline(s) should be at 60% of main frame length, (not including tongue). I put mine at 58% to keep the tongue weight down a bit, but it still tows damn nice for a homebuilt.

Roger

 

On a 16' trailer the centreline of the axles should be 16" back.