Removable Trailer Tongue - Jan 2012 update

[HometownHockeyFan]

Wanna Be, thanks for the clarification...makes sense to me now.

Jeff, thanks for the feedback on your trailer design...nice to see something similar to my plan in use. How much does your TD weigh? I'm looking to use a 2.5x2.5x3/6" tongue since I think my trailer loaded will be 2000+ pounds...which is also why I'm considering alternate designs to deal with the higher weight.

Thanks again for everyone's feedback!!!

David

[WarPony]

Jeff, thanks for the feedback on your trailer design...How much does your TD weigh?

Your welcome. When I was done it weighed in at 625 lbs. I sold it a year and a half ago and the new owners added some stuff to personalize it so I have no idea how much it weighs now.

Jeff

[angib]

Sorry to be late to the party - been a busy week at work.

A 2.5x2.5x3/16 single tongue passes the Australian trailer rules for a 1500lb trailer, but I now think teardrops can double that rating and still be safe. This trailer is a bit of a halfway house between a teardrop and a utility trailer, so that 2.5x2.5 looks OK, though with no spare meat on it.

I second the practical concerns about getting a 2.5x2.5 to slide inside a 3x3x1/8 - if it's going to be slideable, it will have what an old engineer taught me to call a "rattling good fit". That means it will rattle all the time so some way of taking up both the horizontal and the vertical free play would be a good idea.

Receivers don't have a long overhang like tongues so an accessible locking pin doesn't cause a weakness in them. But in a tongue receiver it makes me scream - it reduces the stength of the tongue just at the point of maximum bending. So I would like to see the locking pin moved at least 12" back from the front end of the receiver - I know getting to the pin now involves kneeling or lying on the ground, but that is much, much better than a broken tongue....

The Australian rules say that the single tongue will be just strong enough sideways on its own, but that doesn't guaranteee that the flexibility of the single tongue won't give a shimmy problem, as it has to a couple of forum members. But it would be a shame to have diagonals in the way if they're not really needed.

So my suggestion is to fit it "for but not with" diagonals - brackets welded on the tongue and front cross-member could take diagonals if they are found to be needed or could easily be cut off if not required. With nicely rounded corners they shouldn't do too much shin damage. The ones on the tongue could have bolts so the diagonals stay attached to it when the tongue is out, but will still fold up for easy storage. Pins would be used in the cross-member brackets. Both the bolts and the pins need to be tight fits if they are to work well - too much slop here won't stop the shimmy, just move it to a different speed.

So here's what I've got:

[Bikerman]

[quote="HometownHockeyFan"]Gus,
Thanks for your feedback. :-)

I have not really considered a side gallery...I'll do some tinkering with my drawings and see what I can come up with.

One of the reasons I'm interested in the removable tongue, is the trailer is 12 foot long already...and with my planned use for tailgating in parking lots...I have more options if the trailer is not another 4 foot longer because of the tongue.

I do agree with you on the potential weakness of a single tongue design.

Here are two other options I've dreamed up that allow me to use a Composite Tongue, but still have it removable.

[img]http://www.tnttt.com/gallery/image.php?image_id=77066[/img]

This does not look to hard to make, and I think it would add quite a bit of strength, and still be removable.

Option C
[img]http://www.tnttt.com/gallery/image.php?image_id=77067[/img]

I like this option because it does not interfere with the stabilizers I plan on putting in each corner of the frame. I don't think it is strong as option B because the angle steel will be made of two pieces welded together in order to get the angle I need to get it into the receivers. My other concern is how hard it will be to weld the receivers so the alignment is near perfect so the tongue will remove cleanly.

I appreciate any and all feedback on the two designs

Thanks...David[/quote]

I suggest you bring the 3" to the front leading edge of the cross members and weld in place. The 2 1/2 slides in about 2 feet and about 10 inches forward to weld the head on. The tube inserted is first pined about 8" behind that foward edge and again about 8" from the end of the tub inserted. The longer the insert the less slop you'll have and the tounge will carry more weight tightly doubled up. The forward pin slides in from the top, the rear from the side so a box can go against the front on the tounge.

Use gussets, a triangular plate welded in the corners where each diagonal brace is welded to the frame and tounge. Using gussets at every joint will give you a very strong frame and much less likely that any single weld will ever break, even in an accident. If they are welded on the bottom side they may not interfer with your build on top of the frame, depends on what you do. IMHO

[HometownHockeyFan]

Thanks for the feedback!!

Angib,
Thanks for your excellent input. I share your concern that the single tongue design is a little too close to the specs...even though on paper it should work.

I like your design idea for the bolt on diagonals...and the idea of being able to not use them if actual use shows they are not required.

I'd appreciate your thoughts on the tube size for the diagonals...I might have some leftover 1x2x1/8" tube...but, I have no problems with picking up some larger tube if that is what I need to use.

Bikerman,
Thanks for your input...and I agree that having as much overlap as possible between the tongue and the receiver is a good idea.

Thanks...David

[angib]

I don't think you can make the diagonals too small - almost anything would do. They aren't going to add any vertical strength, just horizontal.

In a wild moment you could even think about just using diagonals in tension, so wire would do! But I think in reality it would be hard to get it to work well.

1x2x1/8 is strong enough as a diagonal but awkward to use - if you laid it flat (2" horizontal, 1" vertical) the joints would be easy, but eventually someone will stand on the middle and bend it - if you stand it up, it will be OK to stand on, but the end joints get harder to arrange with only a 1" width to fit a pin into.

[HometownHockeyFan]

Angib,
Thanks for the additional feedback.

What size material would you suggest using for the diagonals?

Thanks...David

[angib]

I would go for light 2x2 square tube - 11ga or even 14ga would be strong enough and with pinned or bolted ends, there's no welding problem with the 14ga version, plus it's lighter to lift into place.

[eamarquardt]

In a wild moment you could even think about just using diagonals in tension, so wire would do! But I think in reality it would be hard to get it to work well.

Actually I like the idea of wire/chain/simple rod diagonals. As you're gonna get the stiffening you need from tension on each side, I see no need for heavy/rigid members. Sailboats use wire rigging almost exclusively and it seems to work there. As Angib stated, you're not gonna get any vertical support from these so might as well use something light, easy to connect/disconnect/store. A couple of chain links welded to the tongue, a link at each forward corner of your trailer, a bit of chain, a few shackels, and a couple of turnbuckles and you're good to go.

However I still see a removable tongue as a "compromise" and I would opt for a side galley first. Might even be more convienent when tailgating as you wouldn't be near the traffic lane depending on how you park your trailer.

Your call!

Cheers,

Gus

[HometownHockeyFan]

After many months of designing, cutting, and welding...I now have a frame ready to paint. :-)

Here's the final plan. Biggest challenge was how to make an 'A' tongue that retracted..



Here is a top view of the tongue extended



Close of the coupler



Top view of tongue retracted



Side view of tongue retracted



Closeup of the 'C' rail that holds the tongue side rails in place



Closeup of the center tongue rail and pin.



Frame only has a few miles on it, but design so far is exceeding my expectations.

Thanks for all of the helpful ideas that lead me to design and build this. Frame build took just under one year...hopefully the next part goes quicker...

David

[absolutsnwbrdr]

Thats a great idea, as well as nice execution

[wteal]

Help me decide if I'm crazy. I'm wanting to built my first TD and trying to meet multiple needs.

1. I want to be able to carry a 4 wheeler
2. I want to be able to pull it with my 4 banger jeep (will not need a 4 wheeler when pulled with jeep)
3. Only want one TD

So my idea was this. The overall setup is kinda like the Little Guy 6' Sport. The setup would have 6' X 10' TD with 8' being the TD and 2' being storage for propane, A/C, batteries, and ect. Then have a 5' X 6' removable platform for the 4 wheeler that i can take off when not needing the ATV. The tongue would be movable from the platform to the TD when platform is removed. Pin placement would be under the trailer/platform as mentioned in the earlier post on this thread for strength and not at the edge.

In my drawing every 2 squares equals 1' with the exception of the tongue (ran out of room) which is not to scale. Is this design possible? What kind of risk of damage will i be looking at? To better view the pic right click on the image and select save picture as.

[angib]

Six sets of parallel tubes that slide in and out of each other in a welded structure is something easy to draw but something bordering on the impossible to build.

All welding puts heat into the structure which causes some distortion. God-like welders can limit that distortion by carefully sequencing where they weld and in that case you could probably 'slide' three tubes in or out by using a really big drift (hammer). If you have only an ordinary-mortal welder available, you will need a hydraulic jacking/pressing system to force the three tubes into or out of each other.

But otherwise, it's a neat idea!

[Martiangod]

Awesome design.

[Treeview]

David,

Brilliant design and execution! You've completed what is still in my 'windshield engineering' department.

Can the tongue be removed completely for theft-proofing?

Wteal,

Your design is another one that I've thought about. Allowing for welding warpage is going to be important but not too hard to accommodate.

My biggest concern with sliding attachments is the cantilevered loads on the pivot points. This is where engineering and real math comes in. when I'm faced with things like this I look at similar solutions and then use thicker stock.

Tom