Vertical Hitch Pin??? Any thoughts???

[brian_bp]

...In tubing it is the same. I am building my frame from 2 by 3 rectangular tubing If I lay it down 3 inches wide and 2 inches tall it is much weaker than the way I am going to run it 2 inches wide 3 inches tall, even though I have much more metal on top and bottom with the tubing laid the first way.

Right - the strength is dependent on the amount of tension and compression the bottom and top flanges can stand, multiplied by how far they are apart... the taller orientation gains even more from increased vertical separation than it loses from reduced top and bottom flange area. Also, keep in mind that in a box tube the sides are plates which are working as beams themselves... as you approach the top or bottom, you find more highly stressed material, which is why a web would ideally be tapered (thinner in the middle) or perforated (holes in the middle) for best use of the material. That's why semi-trailers which are buit with I-beam main rails often have holes in the webs of the I-beams, omitting material where the stress is low.

You can look up the "second moment of inertia" if you want to know how to calculate the stiffness of a beam shape, but I'm usually not keen to do that much math!

[brian_bp]

It just occured to me that the pin will likely only be removed or inserted when the trailer's tongue is supported by the jack, which means the jack will be rotated into the vertical position, which means a lot better access to the pin location than when the jack is turned up for travel. It seems like any reasonable pin should fit, if that's the case.

One reason that adjustable tongues are sometimes avoided is that they can be another source of unwanted free play, and thus rattling or even annoying trailer motions. Since the tubing is apparently 2" square (inside of the large tube or outside of the small tube) anyway, standard pins as used to secure ball mounts in receivers seem suitable - and the offset location is an innovative way to keep someone else's hardware from working. Among the common pin choices are various systems to reduce rattling, such as the J-Pin from Cequent (Hidden Hitch, Reese, etc.)... it needs an extra hole drilled to work, but this is custom construction anyway.

[oregonguy]

Thanks brian,

I too had thought about the fact that the jack will likely be in the down position when the pin is to be removed or inserted...It'll just be a little tight in general in that area. The more I think about it, the more I am pretty sure that I'll just make a custom pin with very low clearance on one end.

As far as the J-Pin or similar device is concerned...I don't think it'll be necessary in this case. Since I'll be towing in the shortened position 99% of the time, and the overlap is so long in that configuration, there shouldn't be much movement. I Did think about welding a large nut on the side of the tongue behind the diagonal braces and threading a bolt through that would apply pressure in much the same way as the J-hook, but not stick out in the same area that I am trying to conserve space within. I could even weld a T handle on it so that it could be tightened or loosened by hand.

[Jiminsav]

Unless the thief is carrying around a good strong drill with cutting fluid and a set of metal bits along with the extra tongue...

what?..you don't tote those handy items around with you?...
seriously, moving the hole down or angling the hole is a pretty slick idea to thwart thieves.

[Sawyer]

Unless the thief is carrying around a good strong drill with cutting fluid and a set of metal bits along with the extra tongue...

what?..you don't tote those handy items around with you?...
seriously, moving the hole down or angling the hole is a pretty slick idea to thwart thieves.

Well, now that you mention it, I actually do carry all of those things in my truck's tool box!!! But before anyone get's the wrong idea, the tools are for work, and the removable tongue is for my work trailer... And even though I do want to steal oregonguy's teardrop once it's finished, I'd have a hard time hiding it from him since he's my brother and lives in the same town...

[oregonguy]

Sawyer,

makes you think though...how many people have those things in their tool box, maybe just for work, who are less honest, or just not my brother.