Built me a towbar

[jrou111]

If the $350 includes the feet I'm in. I would also want a set of feet for a CUCV.

 

[rat4spd]

Looks good! I only have a small question for you that might have been over looked.

Are you MIG welding them togher? I only ask because I have done it, and took class's on welding and learned that MIG welds are prone to cracking under this type of load over a very short time. This is why 90% of the time that everything in our chemical plant is Stick welded togher. It is more willing to "flex and give" where a mig weld would crack and brake.

A MIG (GMAW) weld properly made with the same filler as a Stick (SMAW) weld has the same strength and characteristics, for the most part. You may be able to argue that the heat affected zones are a little different, but other than that a MIG weld proply done is in no way inferior to a stick weld.

Code work on pipe is an animal unto itself and they have their reasons for specifying stick whether it's a 5P root/7018 fill and cap, TIG root, whatever, but if the person is competent, I wouldn't give second thought to a MIG welded bar. That's assuming he isn't trying it with some 120V machine.

Look at all the welds on large earthmoving equipment, the largest cantilevered bridge girders, ships: MIG welded.

Oh, and 7024 is a flat to15 degree rod only. It's got a high deposition but a low penetration, so it aint getting in anywhere.

 

[rat4spd]

root pass with 6010 (which is a deep penetrating rod) and cap with 7018. You're right about 6013 though. 6013 is mainly used to weld thin stuff.

If you aren't grinding the 6010 out, you might as well cap with 6013, as your weld isn't going to have the strength it would have it you just welded it all with 7018.

 

[powerhouseduece]

A MIG (GMAW) weld properly made with the same filler as a Stick (SMAW) weld has the same strength and characteristics, for the most part. You may be able to argue that the heat affected zones are a little different, but other than that a MIG weld proply done is in no way inferior to a stick weld.

Code work on pipe is an animal unto itself and they have their reasons for specifying stick whether it's a 5P root/7018 fill and cap, TIG root, whatever, but if the person is competent, I wouldn't give second thought to a MIG welded bar. That's assuming he isn't trying it with some 120V machine.

Look at all the welds on large earthmoving equipment, the largest cantilevered bridge girders, ships: MIG welded.

Oh, and 7024 is a flat to15 degree rod only. It's got a high deposition but a low penetration, so it aint getting in anywhere.

Sorry, but I have to respectfully disagree if I may. I was a welder for a while and my last job has the paperwork to prove it! (sucks they wont let you keep the certs.) First off most of the welds on heavy equiment is eathier done buy robot, while running Flux core MIG or Submurged Arc Welding. Also they run very hot, and very fast so that they can do 3-6 passes.

Second, 7024 means that the tensile stringh is 70,000 psi per liner inch, the pisitions are flat and Harzontal (thats what the "2" is for), and I think that the "4" is the type of flux. I have filled 3" "V" gaps and welded 1" plate togher. Then we cut it apart and acid etched it to see the penatration and i can tell you it's the same as 7018 if not more. keep in mind that your running almost 180-190 amps so if the light arent flickering, your not getting enough penatration! I do still have the text books to reger to if you would like!

 

[rat4spd]

There's really no disagreement between us. Dual Shield flux core is a MIG process, yes done robotically on a lot of things. Ship building is done manually quite a lot. Submergerged arc welding is a wire weld process also and quite fascinating to watch. MIG is used quite generically as a term.

I'm well aware 7XXX is 70KSi. 7024, which I've never run because I've never had a need too, is not an out of position rod. Look at the specs on Lincolns website. It's spec'd for 1G,2G, 1F,2F (they consider the vertical groove to be a flat area) only, and spec'd as a low penetration rod. It's a beautiful running rod. Real pretty, and real easy, but flows like water.

If he want to turn every weld into a 1G, or 1F position, it will run well.

I'm not questioning your credentials , but when you say a MIG weld is inferior because it's more prone to cracking than a stick weld, that is false.

 

[jeep thing]

mig if done proper will hold up

every weld on this jeep is mig welded with flux core wire,it was done 4 years ago,i beat the hell out of this thing every chance i get,ive hooked straps up to stuck trucks ,run out the length of the strap at full throttle,by the time the strap stops my jeep some times up to 20-25 miles per our,its like hitting a wall,front tires fly up ,even rear tires bounce up to 2 feet off of ground,not one weld ever even cracked,i allways check because i was leary of the mig weld,but not anymore

 

[powerhouseduece]

Ok guys, if you say so. I will start by retracting my statement. I never said there wasent a use for MIG but I would rather stay with stick welding. Its just that from What I have seen, that unless your Mig is running "perfectly" I have seen welds crack insted of flexing. Granted that any weld will crack under lots of stress, It just seems to me that 7018, 6011 or 6013 will take a little more abuse.

Have a nice day!

 

[rat4spd]

Its just that from What I have seen, that unless your Mig is running "perfectly" I have seen welds crack insted of flexing.

You hit the nail on the head there. MIG if not run properly can cause problems, especially form cold starts or lack of attention to penetration.

 

[m16ty]

If the $350 includes the feet I'm in. I would also want a set of feet for a CUCV.

$350 includes the feet to fit a deuce.

I haven't done the design work for the CUCV feet yet but it shouldn't be too much trouble. They should run $130 for a set of feet.

I'm really not making any profit on these things. By the time I pay the cutter, buy material, and pay my welder I'm just about breaking even. The project just helps keep me from having to lay off some of my shop guys in these hard times if I can at least cover their salary.

 

[rat4spd]

The project just helps keep me from having to lay off some of my shop guys in these hard times if I can at least cover their salary.

That's very commendable of you to do that. I applaud you for thinking of your employees so highly.

 

[m16ty]

That's very commendable of you to do that. I applaud you for thinking of your employees so highly.

I've got some good people and I'm going to need them when things pick back up so I'm trying to hang on to them if I can. Alot of our business is tied to the auto industry and building industry. That's what's killing us right now.

 

[gonorth]

One comment on your pic of the first prototype. Keep in mind I have never used one of these so I may be way off base. The lunette seems to be off center compared to the duece suggesting one leg is longer. I would think that would make the towed vehicle turn harder one way or the other.

For the legs you are makeing, would it be reasonable to use telescopeing material so they could be used with several different tow vehicles?

 

[atankersdad]

You coming to Aberdeen?? Bring me one. In fact bring all you can, I know they will sell...

 

[m16ty]

One comment on your pic of the first prototype. Keep in mind I have never used one of these so I may be way off base. The lunette seems to be off center compared to the duece suggesting one leg is longer. I would think that would make the towed vehicle turn harder one way or the other.

For the legs you are makeing, would it be reasonable to use telescopeing material so they could be used with several different tow vehicles?

Yes, you are right about the hole not being in the center of the first one. That's the way the military towbar is made and I patterned it after that . Don't know why the military one is made that way. The legs are the same length from the center of the lunette to the end where the feet attach so it will pull straight.

The production towbars will have longer legs than is seen in the first prototype. I found out that the longer the legs are the better the towed vehicle tracks. I thing the legs in the pics are 6'. The legs on the new ones will be 8' or how ever long you would like them. I can make them any length as long as I know before I make it. I could make them telescoping but I'd have to go up on the price and you can pull it with any vehicle without having to change the length of the legs.

 

[m16ty]

You coming to Aberdeen?? Bring me one. In fact bring all you can, I know they will sell...

I don't know if I can make it but I'm going to try. If I do I'll bring some towbars.

 

[gonorth]

Thanks for the update. The telescopeing leg I was talking about was the 'leg' you are offering to hold the lunette up in the air when hooking up alone.

 

[m16ty]

Thanks for the update. The telescopeing leg I was talking about was the 'leg' you are offering to hold the lunette up in the air when hooking up alone.

OK. Sorry for the misunderstanding . I thought about what you're talking about too but durring the design work it kind of disappeared in order to keep cost down. If you've ever tried to hook up a towbar by yourself I can see where you're comming from. I'll look into it some more to see if I can add one without the cost going up too much more.

 

[grounded]

or make it a "option"

 

[DUG]

or make it a "option"

I like that idea. I doubt I would ever be hooking up solo. Maybe, but I doubt it.

 

[m16ty]

Update on the towbars- I haven't forgot about the people that PMed me about a towbar.
I'm working on a few right now but the guy that's cutting all my pieces had some trouble with his water-jet cutter and is running behind. As soon as I get some parts it won't take me long to weld them up and then I will have some available.