Trailer hitch connection?

[Willman]

I just got a Post-WWII Light Duty Civilian Utility Trailer (Bantam BT3-C).......It even matches my Taco!:wings:

http://www.film.queensu.ca/CJ3B/HubbardTrailers/Bantam3.html

I need to mount one of those offroad hitch like this one from Adventure Trailers (http://www.adventuretrailers.com/accessories.html). This is a great shot from Scott B's Adventure Trailer writeup (http://www.expeditionswest.com/equipment/adventure_equip/adventure_trailers/chaser.html).

http://i51.photobucket.com/albums/f374/nicwillman/IMG_9730.jpg

What are you guys using on your trailers for a connection??? (Ball, pintle hook, 360' off-road one maybe custom)

Also....If you have one of those 360' offroad hitch...where did you buy it??? (details please)..I would love to hear from people who have are building their trailers and have picked out a hitch setup. Also would love to know what King Camper and other brands use for a hitch setup....And everyone else too....

Thanks!

:jumping:

[Desertdude]

Lock N roll - from adventure trailers (http://www.adventuretrailers.com/accessories.html)

or HERE (http://www.locknroll.com/)

[Andrew Walcker]

Lock N roll - from adventure trailers (http://www.adventuretrailers.com/accessories.html)

or HERE (http://www.locknroll.com/)

X2 :iagree:

[Willman]

Lock N roll - from adventure trailers (http://www.adventuretrailers.com/accessories.html)

or HERE (http://www.locknroll.com/)

Your the man Desertdude!:)

I guessing this is your setup????:hehe:

Thanks for links!!!

[Tucson T4R]

I have King Kamper off road trailer and it uses the Tregg hitch. So far it has working perfectly for me in many high articulation challenges. I like it. I'm not sure where you find one in the US, mine just came on the trailer.

http://i103.photobucket.com/albums/m125/bgarland40/Tregg2.jpg

http://i103.photobucket.com/albums/m125/bgarland40/Tregg1.jpg

[Willman]

Thanks Brad for sharing!!!

Going to have give King Camper a call to see where they get that fine hitch and price too.

:)

Found one on Ebay:

http://cgi.ebay.com.au/TREG-Off-Road-Coupling_W0QQitemZ190103089435QQihZ009QQcategoryZ1 02703QQcmdZViewItem

[Desertdude]

You might want to check if the Tregg is DOT approved in the USA

[DaktariEd]

Lock N roll - from adventure trailers (http://www.adventuretrailers.com/accessories.html)

or HERE (http://www.locknroll.com/)
x3 :iagree:

[Willman]

You might want to check if the Tregg is DOT approved in the USA

Good Question...Brads using one on his King Camper.....you would think that it should be...

:)

[ntsqd]

There is no such thing as "DOT Approved". Our Federal DOT does not approve or disapprove anything. What they do is set minimum acceptable performance standards for vehicular parts. As an MFG when you stamp "DOT" on your product your are certifying that your parts do meet the applicable stds. If one of your parts is determined to have been a cause or partial cause of an accident you'd better have the independent testing lab results showing compliance and the QC documentation showing that subsequent parts were made to the same level of quality.
The German TUV, though, does test & approve vehicular products. Curiously, they use our DOT stds for nearly everything. So a TUV approved part is by default "DOT Approved."

As to the Lock-n-Roll, I have one. There's one feature that I'm not impressed with. That is the swivel joint method, essentially a rivet in tension. I like the Tregg design for this feature soooo much better. The Tregg design copies the 1/4t trailer lunette's design, which has been around for a long time.

[Bob_Sheaves]

An an addendum, the "homebrewer" can make a better design out of some commonly available truck parts-a set of yokes from an 1810 truck ujoint equipped propshaft and scaling up the design of a ball locking hydraulic quick disconnect coupling.

Using the ujoint 1st yoke, machine a square hole in the tube end for a 2" hitch bar and weld securely (I am purposely leaving out the heat treating, annealing, specs etc so everyone has something to look up before attempting this...LOL). Install the 1810 joint to the yoke. This becomes the truck end of the hitch.

Using the second joint yoke, machine a round hole of 2.5" dia in the tube side to insert a machined spud shaft with a retaining ring and groove for the ball retention. Now you would machine a coupler with a sliding sleeve with the ball ramps included and assemble with 12 1/4" dia hardened steel balls. This coupler allows rotation through the ball coupling, fore aft rotation thru the joint, and left right rotation thru the joint also.

Just an idea guys.....

Best as always,

Bob Sheaves
CEO
catNET Incorporated
http://www.catnetsolutions.com/

[ntsqd]

Bob, Just b4 finding the Lock-n-Roll patent back in about '98 or '99 (FEF here may recall better) I designed something much like you describe. My goal was a patent on my idea.
Initially I looked at UJ's (though not as big as the 1810 series) and found them lacking. Memory is dim, what I recall was the bending loads on the cross and tear-out of the ears were suspect. Which I recall making me wonder HTH the Jag IRS' got away with it. Not being all that familiar with larger UJ's (1350's being the largest I've handled) I've no idea of scale. It certainly sounds like it could be large enough.

Getting enough bearing area, fatigue life, etc. inside a 2" sq x .25 wall tube for the "wrist action" took several iterations, but it's doable. I limited myself to 2" tube for the purpose of being able to use std socket receivers on both ends. I do not think that the 2.5" sockets were available then. If they were, I certainly wasn't aware of them.

[Desertdude]

Interesting info...


On one of my trailers, the LocknRoll hitch section between the rivet and the ears, twisted (as in reshaped) - (I later guessed it could have been due to possibly jack-knifing a bit during a tight turn around) still not 100% sure how it could twist?

[Bob_Sheaves]

Bob, Just b4 finding the Lock-n-Roll patent back in about '98 or '99 (FEF here may recall better) I designed something much like you describe. My goal was a patent on my idea.
Initially I looked at UJ's (though not as big as the 1810 series) and found them lacking. Memory is dim, what I recall was the bending loads on the cross and tear-out of the ears were suspect. Which I recall making me wonder HTH the Jag IRS' got away with it. Not being all that familiar with larger UJ's (1350's being the largest I've handled) I've no idea of scale. It certainly sounds like it could be large enough.

Getting enough bearing area, fatigue life, etc. inside a 2" sq x .25 wall tube for the "wrist action" took several iterations, but it's doable. I limited myself to 2" tube for the purpose of being able to use std socket receivers on both ends. I do not think that the 2.5" sockets were available then. If they were, I certainly wasn't aware of them.The 1810 joint is about 6" across the flats of the bearing cups when installed and are all forged (not cast) with a shank diameter of around 2" in diameter. Don't hold me to these dimensions-I am working from memory here, and you know what they say about us old guys and our memory.... :)

The ears of the yokes are some 1.5" thick and are of a bolt in cup design for the joint bearings.

ADDENDUM: The 2.5" dia spud shaft would be on the trailer tongue side of the hitch assembly, so you could pull the QR sleeve and remove the complete coupler from the trailer, leaving only that 2.5" dia spud sticking out horizontally from the tongue and no way to connect any type of ball to steal it.

Best as always,

Bob Sheaves
CEO
catNET Incorporated
http://www.catnetsolutions.com

[ntsqd]

....
Don't hold me to these dimensions-I am working from memory here, and you know what they say about us old guys and our memory.... :)
What they say!
Heck, I experience it first hand daily.

Something like this:
http://i168.photobucket.com/albums/u196/ntsqd/coupler.jpg
I didn't follow your QD idea, so I just popped in something that probably wouldn't work well, but at least there's something there. This may be helpful for some. :dunno:
Oh, Bob, were you thinking along the lines of an air hose QD, with it's captured balls & sliding sleave?

[Bob_Sheaves]

...
Oh, Bob, were you thinking along the lines of an air hose QD, with it's captured balls & sliding sleave?
Same idea...different application. I was thinking hydraulic QD's, because of the larger angle on the lock ramps and the allowance for rotary action in the joint without leaking (altho leakage for this application is not a concern, since you are not sealing in any liquid). Minor point of difference between air and the mil-spec hyd. QD's....no big deal.

Best regards,

Bob Sheaves
CEO
catNET Incorporated
http://www.catnetsolutions.com

[ntsqd]

I'll see if I can amend the model tomorrow.

[Tucson T4R]

I'm still sold on the Tregg hitch. Proven design and has been used for years offroad. The spring loaded pin to couple the Tregg block into the hitch is a simple and easy hook up. I also like that the pivot cylinder on the trailer has grease fittings. Super quiet offroad. Me like it. :jumping:

[RunninRubicon]

I guess I'll just thow in a wrench here and say that I don't have an issue with the original ball hitch. I do pull a light-weight trailer-maybe 700lbs loaded but on only one occasion did I get things out of contol so bad that the trailer tried to roll-over. Because of the inherent limiting characteristics of the hitch it prevented this and kept the rubber side down. No harm no foul. PERHAPS in a heavier trailer the risk of damaging the hitch or flipping both rigs over could I see this an possibility. I see mine working well the way it is thanks.

[Willman]

An an addendum, the "homebrewer" can make a better design out of some commonly available truck parts-a set of yokes from an 1810 truck ujoint equipped propshaft and scaling up the design of a ball locking hydraulic quick disconnect coupling.

Using the ujoint 1st yoke, machine a square hole in the tube end for a 2" hitch bar and weld securely (I am purposely leaving out the heat treating, annealing, specs etc so everyone has something to look up before attempting this...LOL). Install the 1810 joint to the yoke. This becomes the truck end of the hitch.

Using the second joint yoke, machine a round hole of 2.5" dia in the tube side to insert a machined spud shaft with a retaining ring and groove for the ball retention. Now you would machine a coupler with a sliding sleeve with the ball ramps included and assemble with 12 1/4" dia hardened steel balls. This coupler allows rotation through the ball coupling, fore aft rotation thru the joint, and left right rotation thru the joint also.

Just an idea guys.....

Best as always,

Bob Sheaves
CEO
catNET Incorporated
http://www.catnetsolutions.com/

I would love to see a picture of your idea vs. ntsqd idea!

:jumping:

[Willman]

I guess I'll just thow in a wrench here and say that I don't have an issue with the original ball hitch. I do pull a light-weight trailer-maybe 700lbs loaded but on only one occasion did I get things out of contol so bad that the trailer tried to roll-over. Because of the inherent limiting characteristics of the hitch it prevented this and kept the rubber side down. No harm no foul. PERHAPS in a heavier trailer the risk of damaging the hitch or flipping both rigs over could I see this an possibility. I see mine working well the way it is thanks.

Great point!! I have even thought of putting a limit on my new and up coming off-road hitch to prevent roll over.....Still thinking on how I'm going to do it as well.

:)

[ntsqd]

I'll try to update my model to what I believe Bob's idea to be is tomorrow. Work may get in the way though.......

My long shelved design had provision for roll-over control. My thinking was that if you could prevent a "light" trailer flop that is was worth doing, but if the trailer threatened to take the tow rig with it then let the trailer go. My great Uncle had this happen, trailer (early Airstream) rolled and took the tow car with it. He had a little difficulty telling his brother-in-law (my grandfather) what happened.

[ntsqd]

OK, IF I understood Bob's QD concept this is what is would roughly look like:

http://i168.photobucket.com/albums/u196/ntsqd/coupler2.jpg

To disconnect or remove the coupler the red sleeve would be slid fwd against the spring, which allow the white balls to retract out of the groove in the center shaft.

My thot while modeling this is that the averagely gifted, well tooled home designer/fabricator would have some trouble making this work well & last. Just in modeling it w/o engineering concerns I discovered some nuances to the geometry.

I'm sure that it can work, I'd just advise anyone not well versed in this sort of design & fab whom is considering trying it that they consult with someone or multiple someones over the duration of the project.

[bc_fjc]

speeking from experiance I would much rather have the trailer roll and save the truck then risk rolling the trailer and truck or damaging the truck. Both trailer and tent only took minor damage.

[Bob_Sheaves]

OK, IF I understood Bob's QD concept this is what is would roughly look like:

http://i168.photobucket.com/albums/u196/ntsqd/coupler2.jpg

To disconnect or remove the coupler the red sleeve would be slid fwd against the spring, which allow the white balls to retract out of the groove in the center shaft.

My thot while modeling this is that the averagely gifted, well tooled home designer/fabricator would have some trouble making this work well & last. Just in modeling it w/o engineering concerns I discovered some nuances to the geometry.

I'm sure that it can work, I'd just advise anyone not well versed in this sort of design & fab whom is considering trying it that they consult with someone or multiple someones over the duration of the project.DAMN! Ya done good!

That illustrates the concept exactly...altho' it does not address several manufacturing and safety issues (which you have correctly noted), the illustration shows how simple the idea is. Perhaps I am over estimating the capabilities of the "average" homebrewer...but the details are easy enough to work out by following "Machinery's Handbook" & "Mark's" practices.

...or we can cover them here (I don't want to make this a "Bob's Design School" thread and take over) if there is enough interest and the moderators approve.

Best as always,

Bob Sheaves
CEO
catNET Incorporated
http://www.catnetsolutions.com

[Mike S]

On my trailer I designed a simple 360 degree lunette on a .75" shaft that fits through a 3/4" hole in an end plate bolted to a plate welded to a 5' section of 2" square tubing with 1/4" wall. The shaft carries a flat bushing and spring with a double nut to hold it in place inside the tube. The tube fits into the trailer frame which has a receiver at the front of the frame. The lunette fts a standard pintle hook hitch on the Kaymar bumper.

The 'low tech' result is a strong, 360 degree hitch that is adjustable from 18" to 48" in length. Useful on road and off.

Mike S

[Bob_Sheaves]

There is one major issue with any lunette/pintle design and that is one of control over the trailer. A pintle, by design is a sloppy fit to the lunette eyelet. This allows unwanted and undesirable "wobble" in the trailer at high speeds (one of the reasons the military limits their trailers to 55mph max.) due to potential alignment issues with a single, but especially a multiple, axle trailer. The CG of the trailer can be misloaded through carelessness or lack of knowledge and can have a harmonic effect leading to a rollover.

Generally speaking, in the commercial trailer building industry, lunettes are not used under 20K lb GVWR for just this reason. Precise and predictable control over the trailer is a liability issue for manufacturers. Look at the people towing trailers well over 70mph on the freeways anywhere in the US interstate road system...... An accident looking for a place to happen.

I am not saying you are wrong, not at all.. all I am asking is, be careful in what you do.

Best regards,

Bob Sheaves
CEO
catNET Incorporated
http://www.catnetsolutions.com

[Mike S]

Bob

I have a single axle trailer that loads to about 1200 to 1500 lbs. Tongue weight slightly over 10% of the loaded trailer weight. I have hauled it many thousands of miles over the Western states behind my FJ60 and my FZJ80. It tows flat and tracks straight with no wobble or bouncing, even at 70 mph. Guess I'm lucky it hasn't turned over yet.

Mike S

[Willman]

On my trailer I designed a simple 360 degree lunette on a .75" shaft that fits through a 3/4" hole in an end plate bolted to a plate welded to a 5' section of 2" square tubing with 1/4" wall. The shaft carries a flat bushing and spring with a double nut to hold it in place inside the tube. The tube fits into the trailer frame which has a receiver at the front of the frame. The lunette fts a standard pintle hook hitch on the Kaymar bumper.

The 'low tech' result is a strong, 360 degree hitch that is adjustable from 18" to 48" in length. Useful on road and off.

Mike S


Love to see a picture of your hitch setup!!! Sounds like another option....

:chowtime:

[Mike S]

Love to see a picture of your hitch setup!!! Sounds like another option....

:chowtime:

Will, I'll try to post a photo tomorrow.

Mike S

[Willman]

speeking from experiance I would much rather have the trailer roll and save the truck then risk rolling the trailer and truck or damaging the truck. Both trailer and tent only took minor damage.

:oops:....sorry to their about your trailer!!!:(

That has been running through my mind about roll over......TACODOC has a great idea here:

http://i51.photobucket.com/albums/f374/nicwillman/100_1104.jpg

He has made a cannoe rack that i was also going to put on my trailer to also protect incase of roll over for the tent.....

:jumping:

[RunninRubicon]

Neat idea. A roll-cage for your car-top-tent! Has merit.

[ntsqd]

On my trailer I designed a simple 360 degree lunette on a .75" shaft that fits through a 3/4" hole in an end plate bolted to a plate welded to a 5' section of 2" square tubing with 1/4" wall. The shaft carries a flat bushing and spring with a double nut to hold it in place inside the tube. The tube fits into the trailer frame which has a receiver at the front of the frame. The lunette fts a standard pintle hook hitch on the Kaymar bumper.

The 'low tech' result is a strong, 360 degree hitch that is adjustable from 18" to 48" in length. Useful on road and off.

Mike S
Absent a picture, something like this?

http://i168.photobucket.com/albums/u196/ntsqd/swivellunetteslider.jpg

I personally like the spring, not so much from a cushioning point of view, but from a rotational damping point of view. It allows the trailer to rotate relative to the tow vehicle while also providing some damping. Sort of an old friction type shock absorber for this motion freedom.

The Engineer in me does worry that the length of the bushing is not long enough to provide long term rigidity, but if this is the lay-out you have and the various parts aren't showing objectionable wear I certainly wouldn't change the design.

[FEF]

Many years ago, ntsqd gave me drawings for a sweet hitch. I made it real. It took quite a few hours, and was difficult to make.

In the end, after playing with all the custom hitch stuff, I came to a conclucion. To date, as I'm still playing with the modified 5th wheel hitch idea, the rotating (springed) pintle hitch is the best hitch for nasty trails. It's easy. It's simple. You can find parts anywhere. It works.

On a side note, the spring does, in fact, have 2 finctions it provides roll resistance, and it absorbs some shock. As I found out, it won't prevent a roll over, but it will slow the rolling process down. And yes, the down side is that if the trailer goes, the vehicle goes too. It's helpfull, with this type of hitch, not to think of it as vehicle and trailer, but to think of it as an articulated vehilce. Though, there were a few times when I had to jack up the trailer, and push it over. But that's for another thread. :)

A hitch like this:
http://www.northerntool.com/webapp/wcs/stores/servlet/product_6970_200328809_200328809

A ring like this, though I don't know it's vertical load rating.
http://www.northerntool.com/webapp/wcs/stores/servlet/product_6970_200247824_200247824


IMHO

[Mike S]

Absent a picture, something like this?

http://i168.photobucket.com/albums/u196/ntsqd/swivellunetteslider.jpg


That's it. Used two nuts to lock the shaft. The 'tongue' is adjustable for distance from vehicle to the trailer.

M

[ntsqd]

Many years ago, ntsqd gave me drawings for a sweet hitch. I made it real. It took quite a few hours, and was difficult to make.

The worst part had to be the 3 pieces of the 'wrist' feature (axis of rotation parallel to the CL of the vehicles). Somewhere in my several hd crashes over the years I've lost those dwgs. I'd still like to make one for myself, if only just because I can. I still like the original design, but I've a couple improvement ideas that might work. Maybe someday I'll re-create them in SolidWorks & do the full Engineering work-up.....


MikeS, There are two nuts in there, the way they are oriented is one has 2 horiz flats & one has 2 vert flats. They way the section function works they're not all that easy to ID. I took the liberty of adding a cotter pin hole too. The 2" tube started out as a 5' long section, but I shortened it for clarity. Have you by chance reached a maintenence milestone on the coupler? I'm curious how that bushing is holding up. Always good to check intuition against reality as reality has a way of not being quite what you thot it would be.

It's kind of fun seeing if I can model these ideas accurately based solely on a written description. It only looks like showing off. ;)

[Willman]

http://i168.photobucket.com/albums/u196/ntsqd/swivellunetteslider.jpg


What kind of program does this type of drawing??? AutoCad????

:chowtime:

[ntsqd]

What kind of program does this type of drawing??? AutoCad????

:chowtime:
AutoCAD wishes it could do 3D so easily, I started there in Release 11 during the last epoch.
It is SolidWorks. In SW I can do a "save as" & select ".jpg" which gives me a pic file of what ever the current view is.
It would be cool if the board could support eDrawings b/c then anyone looking at the thread could move the view point around and section it as desired. I can send (& maybe attach?) the eDrawings files and the stand-lone viewer is a free d/l.
If you want to see the really powerful stuff check out the program Bob Sheaves has posted images from, Catia

[Mike S]

MikeS, There are two nuts in there, the way they are oriented is one has 2 horiz flats & one has 2 vert flats. They way the section function works they're not all that easy to ID. I took the liberty of adding a cotter pin hole too. The 2" tube started out as a 5' long section, but I shortened it for clarity. Have you by chance reached a maintenence milestone on the coupler? I'm curious how that bushing is holding up. Always good to check intuition against reality as reality has a way of not being quite what you thot it would be.

It's kind of fun seeing if I can model these ideas accurately based solely on a written description. It only looks like showing off. ;)

Your drawing is better than my description! Nice drawing.

I have had this trailer for about 5 years and dragged it all over the West. Last year I pulled the mechanism out of the tube and lubbed it with lithium based grease. No rust or dirt in there at all. But if you're going to be doing river crossings, it might be wise to add a rubber gasket between the two plates and keep it well lubed. You might figure out a workable location for a zerk fitting that would make lube a no-brainer.

Mike

[Rezarf <><]

Very cool Mike!

Drew

[cruiseroutfit]

Mine is a Canadian military unit, where the pintle rotates 360* rather than the lunette (hard mounted to my trailer).

http://www.cruiseroutfitters.com/images/upload/blue6.jpg

Can be locked into position for highway driving if desired (though I rarely do).

The single drawback IMHO over any of the other units is the "clank", though when loaded it is rarely an annoyance.

[Willman]

Well i got my hitch:

http://i51.photobucket.com/albums/f374/nicwillman/DSC02812.jpg

For around $178 wasn't that bad from the Lock N' Roll (http://www.locknroll.com/) web site. Quick shipping and good customer service!

I would have made it myself but did have the time.

I'll keep ya posted on the install coming soon!

:jumping:

[LJRockstar]

Aside from the occasional "klunk" from the origonal setup on my M416, Do they have any issues? Seems to me it's a very stout design. I have more or less eliminated the klunk by installing electric brakes controlled by a Tekonsha Prodigy (http://www.southwestwheel.com/store/p-61-tekonsha-prodigy.aspx). It is one of the best brake controllers I have ever used.

[ntsqd]

Note that the Lock-N-Roll's that come set up to slide into the trailer tongue have the 2" tube bulged at the end to give clearance to the 'rivet head'. If your attachment point has a larger opening than what the 2" x .250 wall tube offers it shouldn't be any trouble.

[Willman]

Note that the Lock-N-Roll's that come set up to slide into the trailer tongue have the 2" tube bulged at the end to give clearance to the 'rivet head'. If your attachment point has a larger opening than what the 2" x .250 wall tube offers it shouldn't be any trouble.

Ten four on that one!!! I'm using 3x3 tube with 3/16 wall for a tonge. That 3x3 plate should weld on their very nice....

:costumed-smiley-007

[ntsqd]

Aside from the occasional "klunk" from the origonal setup on my M416, Do they have any issues? Seems to me it's a very stout design. I have more or less eliminated the klunk by installing electric brakes controlled by a Tekonsha Prodigy (http://www.southwestwheel.com/store/p-61-tekonsha-prodigy.aspx). It is one of the best brake controllers I have ever used.
They're pretty close to Soldier-proof, which says a lot.

http://www.expeditionportal.com/forum/showpost.php?p=78977&postcount=27
I believe what Bob is saying here is that because there is actual slop in the coupling it does not have any built-in damping. A ball-coupler has a fair amount of friction in it, which could serve to damp trailer oscillation. At some point the trailer's inertia exceeds that damping ability and that is when you see various "anti-sway" devices in the trailer to tow rig attachment. I suspect that the formula that predicts total vehicle system maximum safe speed has a variable for this damping tendency, but I'd have to look it up and we're not likely do to that calc anyway.

Speed will be the critical factor. At some speed all trailer systems become unstable. Above that speed the oscillation will feed itself & become progressively worse, in certain cases this is true even if the speed is held constant. What's important is that this speed be far above any speed you're ever likely to go.

[Martyn]

Note that the Lock-N-Roll's that come set up to slide into the trailer tongue have the 2" tube bulged at the end to give clearance to the 'rivet head'. If your attachment point has a larger opening than what the 2" x .250 wall tube offers it shouldn't be any trouble.

We sell a lot of the Lock-N-Roll couplers, in fact I think we are their biggest retailer, We used to see the issue of the bulge in the coupler coming into contact with the inside of the receive tube wall, not allowing it to slide all the way in. It was easily solved by grinding a little on each side so it fitted.

The new batches of Lock-N-Roll couplers haven't exhibited this binding, I think they have made the tube a little longer and placed the location hole a little further back to solve the issue.

We really like this coupler, it's certified for use on road, simple to use, built like a brick **** house, allows for a great range of movement and is not prone to binding. We also have very very few issues with the product so it's an easy item for us to sell.

[ntsqd]

Martyn,
FWIW The one I have came from you, indirectly. My friend Rod Michael bought one of your trailers (in Viper Yellow), and of course he got one of the Lock-n-Rolls to go with it. I was given it to study while Rod was alive. After his death the YJ & trailer were sold and I've still got the L-n-R with no idea who bought the vehicles.

Anyway, it has the swaged or bulged tube end, which is how I knew of the potential issue.

[Martyn]

Martyn,
FWIW The one I have came from you, indirectly. My friend Rod Michael bought one of your trailers (in Viper Yellow), and of course he got one of the Lock-n-Rolls to go with it. I was given it to study while Rod was alive. After his death the YJ & trailer were sold and I've still got the L-n-R with no idea who bought the vehicles.

Anyway, it has the swaged or bulged tube end, which is how I knew of the potential issue.

Rod's death was really a shock for us at AT. We are a tight knit group and when something like this happens it's very sad. We all took a little time to reflected on what are the important things in our lives and set about prioritizing them. Invariably they were family, and trying to spend more quality time doing the things we love, like Overlanding.

Sorry you lost a good friend.

[Bob_Sheaves]

They're pretty close to Soldier-proof, which says a lot.

http://www.expeditionportal.com/forum/showpost.php?p=78977&postcount=27
I believe what Bob is saying here is that because there is actual slop in the coupling it does not have any built-in damping. A ball-coupler has a fair amount of friction in it, which could serve to damp trailer oscillation. At some point the trailer's inertia exceeds that damping ability and that is when you see various "anti-sway" devices in the trailer to tow rig attachment. I suspect that the formula that predicts total vehicle system maximum safe speed has a variable for this damping tendency, but I'd have to look it up and we're not likely do to that calc anyway.

Speed will be the critical factor. At some speed all trailer systems become unstable. Above that speed the oscillation will feed itself & become progressively worse, in certain cases this is true even if the speed is held constant. What's important is that this speed be far above any speed you're ever likely to go.
Correct on all counts. In addition, the longitudinal leverage ratio between the loaded CG of the trailer, versus the offset in the pintle pivot to lunette (see the previous images- the pivot center of the lunette does not corrospond to the pivot center of the pintle, by design), and the loaded CG of the towing vehicle figure into the equation. This is why the military uses (and requires) a driver to have calculated this information to determine convoy speed, if outside normal CONUS operations (meaning tactical deployment, not normal logistic transport). Refer to the data plates on the military trailers and vehicles for the proper calcs. The values used vary, depending on the type of vehicles used.

Best as always,

Bob Sheaves
CEO
catNET Incorporated
http://www.catnetsolutions.com

[elcoyote]

Martyn,
FWIW The one I have came from you, indirectly. My friend Rod Michael bought one of your trailers (in Viper Yellow), and of course he got one of the Lock-n-Rolls to go with it. I was given it to study while Rod was alive. After his death the YJ & trailer were sold and I've still got the L-n-R with no idea who bought the vehicles.

Anyway, it has the swaged or bulged tube end, which is how I knew of the potential issue.

We are in contact with Monty Boswell who bought both the Jeep and Horizon. We will be swapping out Overland for a EeziAwn T-Top. PM me if you'd like to get in touch with him.

[ntsqd]

PM sent.

Will the Overland be FS?

[Willman]

Here are some pictures of the completed Lock N' Roll hitch just incase you are not following my trailer build!!!

http://i51.photobucket.com/albums/f374/nicwillman/DSC02944.jpg

http://i51.photobucket.com/albums/f374/nicwillman/DSC02945.jpg

This hitch is the only way to go!!!!!

:jumping:

[pskhaat]

Great information in this thread, almost to overload for me. What then is the most preferred attachment? I'm still trying to find out why y'all think the simple pintle and rolling lunette are flawed? I was seeing conversations about oscillation in the trailer (due to suspension I assume) and the pintle design contributes to this?

[Willman]

Great information in this thread, almost to overload for me.

Come on...your a Jensen!!!!!!:shakin:



What then is the most preferred attachment?

Lock N' roll (http://www.locknroll.com/) is the only way to go on the 4x4 trails......




I'm still trying to find out why y'all think the simple pintle and rolling lunette are flawed? I was seeing conversations about oscillation in the trailer (due to suspension I assume) and the pintle design contributes to this?

Noise and the hitch movement.

The lock n' roll hitch is a solid connection with out the noise and movement you will get from a pintle. The lock n' roll fixs the problem that the old pintle style has with all the extra slop in the hitch.

Don't get me wrong...pintle is a good connection.....but if you are changing your hitch setup........Lock n' roll is where i would put my $$$$$.

:)

[The BN Guy]

Thank you for posting that link! I've been seeing the Treg setup in A4WD Monthly but didn't know of anything here in the States.

[ntsqd]

Just looking at a lunette/pintle I expect it to be noisy, yet I've read where some folks say they aren't. Which leaves me wondering if some are and some aren't (& why), or if those who claim they aren't are tone deaf. :)

[ntsqd]

Soft springs can promote instability if not correctly designed & installed. Traditional trailer springs are designed to keep fatigue from killing the trailer frame, not allow the instability, and be cost effective to use b/c they require no dampers. Most trailer springs are designed to deflect 1" at their rated max load, and have up to 3" of additional travel for bumps.

I had a look at the formula that can be re-arranged to predict the maxium speed of any tow rig & trailer combo. There is no varible that represents any damping in the coupler, though there is a constant that is only noted as being 'empirically derived'. I suspect that a damping varible might be buried in that, but have no way to back it out. It's not that I think each and every trailer/tow rig combo should have this calc performed so much as I want to know how significant this damping is. If it is tiny then the Critical Speed of pintle/lunette shouldn't be much different than that of a ball coupler or a Lock-N-Roll. If it is as significant as I think it is then each coupler type will have a different Critical Speed and there potentially could be a large difference between them.

For those who might be interested, the formula is below. Everyone else will likely glaze over as it's going to be a mess. I don't blame them.

U = ((sqrt(L^3Y))/(sqrt(2Ih))/{d +(Io - (WtL^2)/g[H/100 - (H/100)^2])/Ih)(Wt/Wc)C}

Where:
U = Critical Speed
L = Tongue Length (hitch to axle, ft)
Y = Cornering Stiffness of Trailer Tires, lbs./rad
Ih = Trailer Moment of Inertia (about hitch, slug-ft^2)
Io = Trailer Moment of Inertia (about CG, slug-ft^2)
Wt = Trailer Weight, lbs.
Wc = Tow rig Weight, lbs.
H = Percent of Trailer Weight at Hitch Point
C = 3.7 (empirically derived)
g = Gravitational Constant, 32.2 ft/sec^2
d = damping ratio (set btwn 0 & 1)

A word on 'd', When at 0 any sway will not change for better or worse. When 1 any sway will rapidly go away. If set below 0 the sway will increase until something, like the guardrail or another vehicle, makes contact & stops it.

Good luck with a number for Y, none of the tire mfg's I spoke to would yield that sort of information.

[Willman]

Soft springs can promote instability if not correctly designed & installed. Traditional trailer springs are designed to keep fatigue from killing the trailer frame, not allow the instability, and be cost effective to use b/c they require no dampers. Most trailer springs are designed to deflect 1" at their rated max load, and have up to 3" of additional travel for bumps.

I had a look at the formula that can be re-arranged to predict the maxium speed of any tow rig & trailer combo. There is no varible that represents any damping in the coupler, though there is a constant that is only noted as being 'empirically derived'. I suspect that a damping varible might be buried in that, but have no way to back it out. It's not that I think each and every trailer/tow rig combo should have this calc performed so much as I want to know how significant this damping is. If it is tiny then the Critical Speed of pintle/lunette shouldn't be much different than that of a ball coupler or a Lock-N-Roll. If it is as significant as I think it is then each coupler type will have a different Critical Speed and there potentially could be a large difference between them.

For those who might be interested, the formula is below. Everyone else will likely glaze over as it's going to be a mess. I don't blame them.U = ((sqrt(L^3Y))/(sqrt(2Ih))/{d +(Io - (WtL^2)/g[H/100 - (H/100)^2])/Ih)(Wt/Wc)C}

Where:
U = Critical Speed
L = Tongue Length (hitch to axle, ft)
Y = Cornering Stiffness of Trailer Tires, lbs./rad
Ih = Trailer Moment of Inertia (about hitch, slug-ft^2)
Io = Trailer Moment of Inertia (about CG, slug-ft^2)
Wt = Trailer Weight, lbs.
Wc = Tow rig Weight, lbs.
H = Percent of Trailer Weight at Hitch Point
C = 3.7 (empirically derived)
g = Gravitational Constant, 32.2 ft/sec^2
d = damping ratio (set btwn 0 & 1)

A word on 'd', When at 0 any sway will not change for better or worse. When 1 any sway will rapidly go away. If set below 0 the sway will increase until something, like the guardrail or another vehicle, makes contact & stops it.

Good luck with a number for Y, none of the tire mfg's I spoke to would yield that sort of information.


WOW......your good!!!!!! Thanks for the post!!

Going to have to check that formula out.....where did you get that??

My rule of thum.....make sure your bearings are all packed....go the fastest you can safety without the trailer going all over the place.....I have found a great speed of 75 that works great for the tow rig and trailer!!!..going to have to try that forumla out to see what that says.....

:)

[ntsqd]

It's from "TRAILERS; How to Buy & Evaluate" by M. M. Smith BSME, Techni-Visions, 1988, ISBN 0-914483-07-2

[slosurfer]

While I think the lock n rolls are great, especially if you like it quiet, I'm still sold on the old pintle and lunnete combo. I used them just about everyday, during my time in the marines, towing and pushing 26ton+ amphibious assault vehicles through all types of terrain. (Mine rarely had to get towed:) ) I have also put over 6,000 miles on my m416, one was a trip that was 5,000 miles plus and never a bad wobble from it. I've even had it up to 40 mph+ through the Oceano dunes and while it does handle different in the sand it still tracked wonderfully. I would imagine the sand is one place you would really see the slop as the sand has a tendency to grab at the trailer wheels and pull it with the terrain, but I don't think it was any different than any of the other moints that have all the available movement.

Mainly my point is that many people who talk down on them have never used them, but read some scientific stuff about the slop and what "might" happen under exactly the right circumstances. I've actually had someone tell me that "lock n roll" was the way to go because it had more movement than my pintle and lunnete. I had to actually prove to him that my lunnete ring could twist 360degrees, to which he replied, "Oh, I don't know much about those."

From my experience, if you load your trailer wrong, you will notice long before you get up to speed that something is wrong. I also believe that if you have your trailer loaded wrong to the point where it is going to roll on you at speed, that there is a good chance that it would have rolled with any of these mounts that have the 360degree movement.

I think the important thing is having one that allows the trailer to flop without pulling the vehicle over, which these all are capable of. I just wouldn't jump into changing a strong and proven system on your military trailer, just because you saw something on the internet about what "might" happen. If you want to change it to something quieter, that's great, but it is a very good system.

[Azrocks]

I guess I'll just thow in a wrench here and say that I don't have an issue with the original ball hitch. I do pull a light-weight trailer-maybe 700lbs loaded but on only one occasion did I get things out of contol so bad that the trailer tried to roll-over. Because of the inherent limiting characteristics of the hitch it prevented this and kept the rubber side down. No harm no foul. PERHAPS in a heavier trailer the risk of damaging the hitch or flipping both rigs over could I see this an possibility. I see mine working well the way it is thanks.

x2. I really don't see the need to use anything other than a good ole fashioned 2" ball and good hitch. K.I.S. I just don't like all the added points of failure in the swivel designs. They will wear out over time. Just another opinion.

[Willman]

^Ball hitches are not meant for hard offroad use.....Your trailer could flip you and your rig over on rough road.....Moab, Rubicon trail and others would eat a ball alive!

http://i51.photobucket.com/albums/f374/nicwillman/DSC03618.jpg

A pintle hook or a Lock n' roll would be the only thing i would take offroad.

This is a huge safety thing.



....added points of failure in the swivel designs. They will wear out over time..

In my opinion, I don't think this a concern.....everything is solid and well lubed on mine.....



Just my two cents

;)


And.....Welcome to the ExPo Azrocks!

[MoGas]

The Lock 'N Roll is great if you need quiet operation, but for my money a pintle hook with a swivel lunette is the only way to go as far as strength is concerned. What is the LNR rated to?

[Willman]

^6000 lb Gross Trailer Weight

:camping: