Need help making a tow bar.

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Today I discovered the tow bar on our 6cf cement mixer is in rather bad shape. The loop is worn half way thru from contact with the hitch.Also the loop is bent and the weld is cracking from someone backing up while it was hooked on the truck.My boss wants me to make a new tow bar.The plan is to:-use a length of 40wt 2-1/2" pipe, the same we use for commercial fence posts. it looks like the original is 40wt.-Buy a u-bolt and weld it on.A quick search online didn't turn up any u-bolts this size/shape without threads for the distance I need (6" long, 2-1/2 wide)Do I need to buy a 3/4 bar, heat it with the torch, and bent it to shape?Closest thing I have on hand is one of those bars truckers use to tighten down their loads. It looks like stainless, I'm not sure.-Cut a hole for the mounting bolt with the torch.My biggest question is: Is there any chance that this needs to be heat treated? If It does, than I'll try to get him to buy a new one.Any other advise is more than welcome.I have a Millermatic 180 with .035 flux core that I use on a daily basis.Or I can use my 230/140 AC/DC stick welder, but I just got it and I'm not really comfortable with it yet.Mixer is a Best 65CM Attached Images
Reply:Looks like you must be running a pintle hitch arrangement. It really should be hardened/specially made because of the hi-way use. Do a search for lunette rings. http://www.google.com/search?q=lunet...e7&rlz=1I7SUNA"The things that will destroy America are prosperity at any price, peace at any price, safety first instead of duty first, the love of soft living and the get rich quick theory of life." -Theodore Roosevelt
Reply:Yes, it is a pintle hitch, like the picture.Also 2 more pics. Attached Images
Reply:Luckily mixers don't have all that much weight, but they do take a lot of abuse. I wouldn't go the build it yourself route on the ring unless it was an emergency measure. I'd run down to the local equipment dealer and see what toys they had in stock. My 1st thought would be one of the large round single bolt lifting eyes followed by a light weight bolt on pintle ring  or a weld on one and weld it to the pipe. My next thought would be one of the heavy duty D rings for trailer tiedowns. I've seen the rings done with lighter materials before but usually they all broke or wore or fairly quickly. Mild steel bends too easy, and rebar can become brittle after welding and snap without warning. To me the MM180 is borderline if cranked up for this. I'd rather use stick and get better penetration. That said, if you do this, I'd use the process that you can do best and run it hot and heavy with good prep..No government ever voluntarily reduces itself in size. Government programs, once launched, never disappear. Actually, a government bureau is the nearest thing to eternal life we'll ever see on this earth! Ronald Reagan
Reply:hi, this might be a dump question but, do you tow that mixer on the road?I would just build up the worn section will some weld.
Reply:If it were ME...1) Purchase the Lunette Ring similiar to the one shown above,(Thanks Sandy for the Links) 2) Mate it up to a 1/2" or 3/4" receiver plate (Whatever thickness is appropriate) that was drilled out to the same pattern, and had a hole in the center of the plate the same as the O.D. of the pipe you are using for the reach.3) Bevel the edges of the circle, and weld the plate onto the reach, on BOTH sides of the reciver plate.4) Bolt the new Lunette Ring to the receiver plate with Grade 8 Hardware and Distorted Thread (Stover) Lock NutsIn future, replacement is a breeze... The Lunette Ring can be removed to deter theft.It will look a LOT more Professional on a Job Site than the current arrangement.Last edited by Black Wolf; 07-01-2010 at 08:45 AM.Later,Jason
Reply:Never knew they were called Lunette Rings before, always just asked for a pintle ring and got what I needed. There's any number of options shown here.http://www.easternmarine.com/Pintle-...910&OVNDID=ND1The 1st 2 shown would be my 1st choices. Attached Images.No government ever voluntarily reduces itself in size. Government programs, once launched, never disappear. Actually, a government bureau is the nearest thing to eternal life we'll ever see on this earth! Ronald Reagan
Reply:Good Morning Doug,I would agree with you that the Lunette Ring shown above is far superior to what I suggessted, but it in this appication, it seems to be a touch of Overkill, and also it raises the question :HOW does one tighten that nut and install the cotter pin when the mounting plate is attached to a piece of pipe several feet long?In reality, this adjustable unit shown above, is probably MORE than what is needed, if welded out PROPERLY....But I erred on the side of caution because of the questionable welding machine, and unknown operator skills.In any event, Have a Good Day.Last edited by Black Wolf; 07-01-2010 at 09:20 AM.Later,Jason
Reply:Thanks for the help guys.Do you think it would be ok if I just used the adjustable one and welded the bracket right to the pipe?Its rated at 12,000lb GTW, 2000lb vertical load.Yes, I was planing on beveling the pipe.No one said anything about the pipe so I guess 40wt mild is ok? Attached Images
Reply:Why not just put a 2" ball setup on it and be done with it? No need to reinvent the wheel IMO, unless you need that pintle hitch for something else.
Reply:The component you are showing has capacities well beyond your application, so Yes, it should be significantly more than adequate, if welded out properly.I have no information as to your welding skills, so you will have to forgive me, but if you bevel the pipe, and run sound welds, this WILL have a good service life on that piece of equipment. Given the two choices, I would lean towards the SMAW welder, and a 6010 Root, 7018 Hot Pass & Cap, but that is just ME... You will probably have a sounder weld with the Flux Core welder if that is the one you have more experience with.Either way, use an Uphand weld progession and weld from bottom to top to help ensure good penetration.  NO DOWNHAND WELDS.I am not familiar with cement mixers, so I am taking your word for it that the current "Reach" is Schedule 40 Pipe. From your picture, it appears that the front leg of the mixer is sleeved, and the reach can be slid through the leg to reduce a tripping hazard -  If this type of reach came with the mixer from the manufacturer, and it has no signs of being bent or deformed, then it should be more than suitable for the application.  I do not suspect there is much of a vertical load, as pretty much all of the weight appears to be over the tires. Hope that helps.On Edit: I went back and checked the O.D. you specified for the pipe against the measurements you have shown for the adjustable bracket  - Only issue I can see is  having enough room to run sound welds around the pipe, on the backside of that bracket - If the 3-1/2" is on the INSIDE of the bends, you are in business,,, If the 3-1/2" is to the OUTSIDE of the brackets, you are gonna be tight, and welding against the radius of the bends.Last edited by Black Wolf; 07-01-2010 at 10:47 AM.Later,Jason
Reply:Originally Posted by minnerWhy not just put a 2" ball setup on it and be done with it? No need to reinvent the wheel IMO, unless you need that pintle hitch for something else.
Reply:Originally Posted by minnerWhy not just put a 2" ball setup on it and be done with it? No need to reinvent the wheel IMO, unless you need that pintle hitch for something else.
Reply:Originally Posted by DSWJason almost any of these shown are way overkill. I doubt the mixer weighs more than 500lbs, 350 or less would not surprise me. I was thinking, just loose the nut and slip fit the bolt in the pipe and weld the circumfrence where they meet.  The advantage of this is that the ring can piviot a bit to help keep the wheels of the mixer on the ground.
Reply:One big problem with these hod and cement mixers is they get jacknifed just about every other time they go out on the job. They're so small you can't see them and can't control them backing up. Guys will jacknife them then decide to go ahead and skid the thing sideways while in the jacknifed position. Skidding a 300 pund mixer sideways in the dirt takes a pretty good hitch.  Close to beer thirty and the barn whispering their name they don't spend much time trying to jocky one around, and dern sure not by hand at the end of a long hot day."The things that will destroy America are prosperity at any price, peace at any price, safety first instead of duty first, the love of soft living and the get rich quick theory of life." -Theodore Roosevelt
Reply:Updatearrggh! one of these days I'll have a job were I can make things the right way.I showed my boss the part I needed and he comes back with a Kuplex rigging link thats 5/8" too wide, and tells me it needs to be welded up today. So, no time to change his mind.At first I used a 3/32 rod to help fill the gap, but after my first pass I flipped it over and I wasn't happy with how much the rod was blending into the weld, so I ground it out from the back and filled it with weld.It looks ok, accept for the way the weld looks smooth next to the pipe but rough next to the ring. Is this because of the rings high carbon content? Is this a problem?I used NR-211-MP .035On the plus side of the day I got a killer deal on a bunch of 6010, and 7018, so as soon as I finish my welding cart, it's pratice time.First pict is my root pass. Attached ImagesLast edited by Blueduck600; 07-02-2010 at 06:55 PM.Reason: photo cap
Reply:Your Boss made you use a Master Link?...Wow... That is wrong in more ways than I wanna explain...Later,Jason
Reply:Could you try to explain anyhow?If its bad enough maybe I can convince him to get the right thing.Sh*t like this happens all the time. I do the research on doing it right and he ends up buying whatever the moron behind the counter tells his to.
Reply:Let me clarify, if this is dangerous I'll make sure it never sees the road.Is this ring ductile iron?The mixer is going out on tuesday, I can put the old tow bar back on till I work this out.(I don't know how much better that is.)
Reply:I don't want to get you in trouble but you need to tell your boss to pound sand and do it right before he kills someone with his half-assed attempts at saving money.....Welding on a master link which usually is made out of high tensile heat treated steel alloy is not something most if any would suggest. i'm not an expert but I'd say make sure it doesn't see the pavement. I'm not dogging you, just your boss."...My pappy was a pistol I'm a son of a gun...""...God is great, beer is good, and people are crazy..."
Reply:I am no "Expert" in all aspects of hoisting and rigging, but I have been trained enough to know that what your Boss made you do, was a VERY BAD idea...The component you used was intended for use in Overhead Hoisting applications.,.. It is made of a Very High Strength, VERY Brittle form of steel... It is incredibly strong when subjected to Static Loads, but will fracture, or SHATTER when acted upon by strong Dynamic Loads...Hanging on a Crane with a load slowly applied and suspended - Static Load - Good.Your intended application - jack knifing, binding - Any quick Loading/Unloading - Dynamic - BAD.It may break apart and shatter at any time without warning.It will probably snap the first time you bind it up when jack-knifing.That material was NOT designed to deform and bend like a System 70  Transport Chain will... It will BREAK.Welding it made it WORSE.Wrong component in the WRONG application.If THAT is all the Boss was willing to spring for, you would have been better off to bend a piece of Hot Rolled and slap it on there - At least the Mild Steel will deform before it breaks.Last edited by Black Wolf; 07-03-2010 at 01:57 AM.Reason: SpellingLater,Jason
Reply:It may be too late now but, another name for them is tow rings. Wallace Forge has a nice lineup. They make different sizes with smaller ones perfect for small equipment, like mixers. Such as the first one marked, "Rigid Mounted Tow Ring" . We have some on the shelf in our store at work.http://www.wallaceforgecompany.com/tow-rings.aspxCity of L.A. Structural; Manual & Semi-Automatic;"Surely there is a mine for silver, and a place where gold is refined. Iron is taken from the earth, and copper is smelted from ore."Job 28:1,2Lincoln, Miller, Victor & ISV BibleDanny
Reply:One of my thoughts with a bolt on tow ring like Black Wolf's post #6 is that it's yours to reuse later. Put plate on the end of the tube with a couple of gussets and bolt it up.  It won't wear like the mild steel does, won't bend out of shape like the old home made did, and when they bend that tongue you can unbolt it and use it on the next one. The only thing you are out is the plate and gusset material. Not using a bolt on ring then, as mentioned,  you just as well go back to the home rolled version like the original. The only real strength there, regardless of pounds of rod poured into it, is the wall of the pipe/tube. I don't know what the actual wall thickness is on 2.5 inch schedule 40 is but it isn't substantial. My guess is that you could easily tear the wall out of that tube with a piece of 1/2 inch bar stock properly welded so anything bigger than that would work to allow for some wear time."The things that will destroy America are prosperity at any price, peace at any price, safety first instead of duty first, the love of soft living and the get rich quick theory of life." -Theodore Roosevelt
Reply:Thanks for the explanation Black Wolf.Today I put the old tow bar back on and told my boss I couldn't use the master link. That didn't go badly, and it looks like he is going to get the right part.Unfortunately, the concept of brittle steel still evades him.I'm going to try hitting the link with a sledge hammer in the hopes of a good object lesson. that'd be fun.tanglediverThanks for the great link, that's going to help. For those who didn't check it out, it describes how, if at all, the different tow rings can be welded.
Reply:HOLY CHEERISTGet some 3/4 or 1" cold roll round stock, whip out your handy dandy rosebud, and bend it to fit, then weld it up.AAAARRRGH Attached Images"Any day above ground is a good day"http://www.farmersamm.com/I don't have a handy dandy rosebud.The idea is to minimize the type of wear that caused the original problem. Not replace it with the same thing. Assuming the original was mild steel.
Reply:Then quit foolin' around, AND DO IT RIGHT!!!!!! Attached Images"Any day above ground is a good day"http://www.farmersamm.com/
Reply:A quick Google for "weld on lunette best prices" shows plenty of hits, and they aren't expensive. I get the solid forgings, not the hollow rings.I have a couple of this style in use, but welded rather than pinned (the shank being handy for either use):http://www.northerntool.com/images/p.../330440_lg.gif
Reply:I had a look about with the camera today. Notice the difference in size? The bolted versions are way, way beyond overkill!   Attached ImagesCity of L.A. Structural; Manual & Semi-Automatic;"Surely there is a mine for silver, and a place where gold is refined. Iron is taken from the earth, and copper is smelted from ore."Job 28:1,2Lincoln, Miller, Victor & ISV BibleDanny
Reply:Psssssst.............1" cold roll"Any day above ground is a good day"http://www.farmersamm.com/
Reply:Originally Posted by farmersammPsssssst.............1" cold roll
Reply:Go get 'em Sam..."The beauty of the Second Amendment is that it will not be needed until they try to take it." - Thomas Jefferson If the Lights are a Flashin', STAY OFF the tracks!!! It might be me at the Throttle...
Reply:summa da beach, look at those prices....
Reply:The 29.95 version with the square end to insert in a Reese hitch will work fine and has ample room on the shank for welding. Bizarre price variation in that store. Ouch.
Reply:Originally Posted by farmallBizarre price variation in that store. Ouch.