another M416 hitch question

[hey you]

Long time lurker and I am truly inspired by the trailer builders here in Mud. I’m looking for ideas (pictures) to help me design/build/replicate a sliding/extended receiver tubing about 12” or so. I currently have an M416 with the lunate/pintle configuration. I know there are several opinions on keeping the lunate/pintle configuration verses a multi-axis coupler. I want to move the trailer back so that I can safely maneuver and articulate with the trailer and not damage my FJ40 or the trailer. I’ve read through several posts and searched but I’m not finding any examples from what might have already built.

I have a couple of questions, any thoughts and how did you make the changes?

· How did you change your lunate to a multi-axis coupler. I have the ability to build my own adapter plate and adapt to the M416 frame.
· Can a multi-axis coupler be welded safely to 2x2” tubing to extend the receiver tube?
· Extended the 2” receiver tube, 12 or more inches when off road. Retractable 12” or more when towing on the highway.
· Is the 2x2x.25” tubing strong enough to extend 12 to 18 inches and handle a loaded M416 @ 500lbs off road. Nothing crazy…

Thanks!

 

[ntsqd]

Was it me I would un-bolt the whole lunette assembly from the tongue of the trailer. Then fabricate mounting plates that bolt in the same way with a long 2" socket receiver tube welded to them, with gussets as appropriate. Take another long receiver tube and partly slip the rear of it over and then weld it to the end of a piece of 2" x .250" wall tube using both rosette and T welds. Drill a couple coupler pin holes in the 2" tube at different lengths along it. Now you have a socket receiver on the variable length tongue that you can plug in whatever multi-axis coupler suits your fancy.

 

[Brian in Oregon]

Was it me I would un-bolt the whole lunette assembly from the tongue of the trailer. Then fabricate mounting plates that bolt in the same way with a long 2" socket receiver tube welded to them, with gussets as appropriate. Take another long receiver tube and partly slip the rear of it over and then weld it to the end of a piece of 2" x .250" wall tube using both rosette and T welds. Drill a couple coupler pin holes in the 2" tube at different lengths along it. Now you have a socket receiver on the variable length tongue that you can plug in whatever multi-axis coupler suits your fancy.

 

[hey you]

Something like this? Do you think it would be strong enough?

 

[Mark Harley]

I have bought several receiver tubes from this seller.
They are formed nice, have a collar for strength and weld great.

http://www.ebay.com/itm/2-x-12-rece..._Camper_Parts_Accessories&hash=item3a5f1fe912

Fab a new V from plate steel and keep the original lunette mount for restoring it back later.

 

[ntsqd]

Something like this? Do you think it would be strong enough?

Usually those are solid 2" bar stock (unnecessarily heavy) and not nearly long enough for this purpose.

 

[e9999]

if you buy 2" tubing, both ID and OD, I'd make sure they are 1/4" thick. Unfortunately, a lot of the less expensive ones out there are thinner -and it's usually hard to find out the thickness upfront from the less technical vendors-.

yes, a receiver extension is perhaps the easiest and cheapest way to go, and you would indeed want to make sure it's a solid shank (which likely won't be the case for the cheaper ones a la HF or NT). But that's probably only 24" max off the shelf. Good to have around for a number of things though, although keep in mind that the leverage on the hitch receiver increases and the load rating of the receiver should be treated as lower accordingly.

I think generally speaking that you would probably be fine with a 2x2x1/4 tube section of 12" or even 24" long for a small offroad trailer as far as structural strength. And worse thing that'll happen it may become a bit bent, no biggie. Unlikely it'll flat out break. You'll likely want to deal with the slop if you have extensions though (see other threads here).

 

[hey you]

Thanks guys, I'll start working on this next week and submit a couple of pictures as I go.

 

[Dell]

IMO

The length of the tongue on the trailer...
should be determined by the wheel base of the hauler.
and also that it clears the tow vehicle when backed into a 90*

an excessively long tongue will not help matters
if taken on a trail or other diverse terrain.
Matching the wheel base of yer hauler will offer the best
all around towing... and best handling (trailing)

I don't have the same trailer...
but can share what I did to my M100 to add a Max Coupler.
It could be duplicated on most any trailer with a lunette casting.

I also chose to keep my lunette/casting intact and functional
by simply removing/replacing 5 bolts. (it's there as back up)

Here's a picture of that...

http://i1191.photobucket.com/albums...re Mount/M100sparetiremountfinishnpaint29.jpg

http://i426.photobucket.com/albums/pp344/TTORADell/M100 trailer on the job/truckntrailer3-1.jpg

a video clip showing how I use it... Pinyon Trail w/trailer in tow
^ there are more Youtube videos in the thread.

Here's my original/most current build thread

It's posted here as well... but likely not current/updated.
Be forewarned... it is a long thread/read...
but has a bunch of pictures offering more perspective.

* you could weld the coupler into the tubing...
But I'd think a 5/8" pin or anti-rattle lock would be better
in case you need to change things.

 

[hey you]

Thanks Dell,

I've been pouring over your build for a couple of weeks now. I told you I was lurking... Great ideas and a great trailer. I have an FJ40 with a spare tire carrier with a basket for fuel and water cans. Jack knifing the trailer is out of the question. In fact, just a making a normal turn on the street is risky.

So, I really need to extend the frame or engineer the receiver tubing. Taking into consideration your build, I also would like to carry the spare tire on the A-frame of the trailer.

Ideally, 42" extended A-frame (from the cargo box to the coupler) would suit me better. I'm still mulling over the idea.

 

[hey you]

I will probably go this route. Dieselcruiserhead built a nice, clean, and simple extension. This will extend the A-frame about 40". With the lunette it will add additional 12" to a total of 52" . If I convert to a receiver tube, I can shorten or lengthen the receiver a couple inches. With this build, I can also add the spare tire and not have any problems jack knifing the trailer using my FJ40.

http://www.expeditionportal.com/forum/threads/20925-M416-Build/page6

 

[ntsqd]

IMO the length of the tongue during normal use should be that which sets the tongue weight proportionately correct. You can do what is effectively a Shear-Moment diagram (& it's a good idea to do so regardless - see the link on tinytrailers.com) or you can apply a Rule of Thumb. The rule that I use is that the tongue length should be 1/2 the distance from the ball to the trailer axle. Then I do a Shear-Moment diagram to check that it works out. One trailer built like this has been certified stable to at least a sustained 80MPH on Mexico's Hwy 3 north of San Felipe. Or the driver was the certifiable one, but the trailer was stable at that speed, and it backs up better than all but one other trailer that I've pulled. That other trailer was also built using this RoT.

The 80 MPH trailer, post testing and looking a lot like Sanford & Son are using it:

 

[hey you]

Ok, I have a different approach. Knowing your gross trailer weight is critical to properly adjusting the tongue weight of your trailer. I’m expecting the tongue weight to fall within the 10 to 15-percent weight range of the gross trailer weight. The gross trailer weight is 680 lbs. (metal lid and RRT) with no added weight because I’m re-using the a-frame. Now to balance the tongue weight correctly, I figure the tongue weight (range) to be 68 to 102 pounds. I would need to put the weight forward of the axle, roughly 100 lbs. Therefore, I could add the spare tire or 10 gallons of water and safely travel with this trailer. Loading the trailer with camping gear is also equally important as not to over load the tongue. I wouldn't consider the weight of my camping gear (forward of the axle) exceeding the tongue weight by much.

Its all about the balance. 80 mph isn't possible in my FJ40. With the in the truck, the tongue lashing would not be safe.

 

[ntsqd]

What you're describing is what I suggested doing, only on paper first. Can find the ideal tongue length before ever cutting any metal.

 

[Dell]

Ideally, 42" extended A-frame (from the cargo box to the coupler) would suit me better. I'm still mulling over the idea.

Mine measures out to 46"

 

[hey you]

Well, after a week of brutal temps in the garage, I managed to extend the "A" frame of my M416. Using remnants from the local metal yard to keep my costs down, I fabricated the extended hitch. I also discovered that the trailer frame was tweaked pretty badly from hard use. When I separated the lunette bracket, the frame unwound like a twisted rubber band.

After separating the lid, RTT, trailer box, axle, hitch, wiring, and lights. I attempted to straighten the frame so that it measured square and level. I then welded in 3x3x.25 tube at the front of the trailer frame. I measured and cut the “A” frame to match the angle of the 3x3. After more measuring and frame tweaking with heavy chains and my hi-lift, I welded in the center 2.5x2.5x.25 receiver tube. I had to pull the “A” frame together about 1.50 inches so that I could weld it all together. I also welded in a receiver tube in the rear of the frame to carry mountain bikes.

I gusseted the “A” frame with 4x4.25 and 6x6.25 plating to give it more strength. I used 1.75X.25 strap to level the top/bottom of receiver tube with the “A” frame so that a deck or box can be added later. You can see some of the strap I used to keep the frame straight on the bottom of the receiver tube. I haven’t decided if I should leave in in place. I also welded in a new removable jack and ordered a max coupler.

I also did a bunch of grinding and cleaning before and after welding. I still had a bunch of problems with clean welds. I ended up switching to new .035 wire and tips, rebuilding my ground clamp and that seemed to fix my poor welding. I still had problems with contaminated welds from all the junk on the metal. I hope to reattach the axle to the frame tomorrow and get it to a sand blasting shop. I’m done grinding…

I will tell you, use respirator protection and a well-ventilated area when working on these trailers. I figured I added about 50 pounds of metal to the trailer. I’m not sure how much weight I removed when I separated the lunette, bracket, and landing gear. I should be pretty close to being the same, keeping the trailer balanced correctly. I would like to add a spare tire carrier and water on the front frame, more on that later.

Once the frame and box are done and sand blasted, I’ll get the trailer painted. I’m thinking of keeping the camouflaged look.

 

[hey you]

Here a three photos.

 

[hey you]

Look what brown delivered just now! The total extension from the front of the trailer box to the end of max coupler is exactly 48 inches.