There is something very wrong, that mounting tab has radial and lateral cracks and a concave surface that indicates that the bolt was being pulled through and I don't see any indication of a washer, it looks like the bushing is a hi density encapsulated bushing which would absorb a lot of the shock transmitted to the bolt and that mounting tab is absolutely horrible, who ever welded it ought be run out of town, it was welded with a MIG welder that was way out of adjustment and if you look at the weld you can see undercut and non adhesion, it's amazing to me that it's still there, I think there's a alignment problem somewhere that needs to be fixed because by all indications that tab was subject to some very heavy side forces, there's more to this than being told IMHO. The body needs to come off and a serious look at the alignment needs to be done, something got whacked or moved, there's more than just that bolt that's a problem, once again IMHO.
Ted
Originally written by Shadow1100T on 5/16/2007 9:16 AM
There is something very wrong, that mounting tab has radial and lateral cracks and a concave surface that indicates that the bolt was being pulled through and I don't see any indication of a washer, it looks like the bushing is a hi density encapsulated bushing which would absorb a lot of the shock transmitted to the bolt and that mounting tab is absolutely horrible, who ever welded it ought be run out of town, it was welded with a MIG welder that was way out of adjustment and if you look at the weld you can see undercut and non adhesion, it's amazing to me that it's still there, I think there's a alignment problem somewhere that needs to be fixed because by all indications that tab was subject to some very heavy side forces, there's more to this than being told IMHO. The body needs to come off and a serious look at the alignment needs to be done, something got whacked or moved, there's more than just that bolt that's a problem, once again IMHO.
Ted
Well in fairness to the original builder, I think the weld was probably OK until they had to use a cutting torch to remove the bolt which according to the blog, wouldn't come out. After all of that cutting slag, it's really hard to tell how it may have looked originally.
That would explain all the dingle berries but it doesn't change the fact that the weld is,,,,,well, not what it should be. I would have things torn apart to find out why it doing what it's doing, I get ill just thinking what could happen if things let loose cruising at 60. I hope everybody doesn't think I'm being to critical, it's just that stuff like this upsets me for a number of reasons, which I won't go into, lets just say that I'm fussy, very fussy and safety oriented.
Ted
I just took a couple pictures to show what looks like these bolt for those who have not seen the bracket before failure.
http://twintwin.smugmug.com/gallery/2857763#153326092
I have the same rig as Ara, and we keep close contact, especially when he has a breakage. I took apart the arm that connects the tilt and the shock for a closer inspection. Mine looks fine for now!!!
I do not know the grade of this bolt (no writing on it but the 2 other ones, tilt and shock are the same diameter 1/2 inch and grade SAE 8.8). Apparently this bolt was use before to hold the shock in the Ural chair, and when the tilt addition was made by Daunltless, this same bolt was use as the pivot axle in the arm. It is welded inside a small bracket that you can see in the picture. Why it broke, no clue, but if someone have some explanations and can give us some advises to make it stronger I will appreciate.
Thanks
Didier
Well first off your to be commended for going through what you did to offer some pic's that make things a LOT clearer.
As I see it there are 2 things that could have happened, 1. At the time of mfg. the stud when welded wasn't welded correctly, what can happen is slag from the welding process can migrate between the stud and the block, when this happens it will force the weld up and the penetratration needed to hold the stud is compromised, it will look good on top but underneath it's just marginal and unless the fit on the stud is really tight the stud will flex and fatige the weld, what there is of it untill it brakes.
The second thing that can happen is that when the stud is welded for one reason or another the stud crystallized, this can happen when a hard material is subjected to a lot of heat, enough so that when it cools it becomes extremely hard, very hard materials will take a lot of pressure but will not tolerate a shear force, they brake.
If it's still possible to see the old stud one can see if it did snap because of it being hardened, when looking at it there will be a dark area and a light area, the dark area is from a hair line fracture in the stud formed after it cooled, the area that snapped will be a grayish white and look as if it was pulled apart which it was.
I think I would check with the factory and see if they used a lesser grade bolt, it wouldn't surprise me if they did, a lesser grade has a lot less carbon in it and won't harden from the heat of welding. The main thing on this repair is the condition of the hole in the mounting block, it had to be tight because if it isn't the replacement bolt will elongate the hole and sooner or later there's going to be a problem,,again.
What i think should be done is to take off the block that's on the rig, have a machine shop drill and ream a hole for the stud, put the stud in and weld it, position it on the frame and weld it, one other option is rather than welding the stud is to just use a bolt, when the hole is reamed make it the same size as the bolt, heat the block and freeze the bolt and put them together and then drill a hole and use a roll pin to secure it from moving, it looked like there was plenty of room for the head of the bolt on the back side of the block. no mater what is done it's going to be a bit labor intensive.
Ted
Very nice photos. Thanks. I think when the bolt ws welded in place, it may have gotten brittle. One thing is sure, it holds a lot of weight and is under quite a strain. I think it would be fairly straightforward to make a new perch on top of the bracket that has a larger diameter bolt. It looks like it would be possible to use a bolt that goes all the way through and is only tightened rather than being welded in and modified.
Thanks guys for your expertice and advises. Now look at Ara blog, and you will see the new mounting bracket for the bolt. One plain scare piece of metal drilled in the center, one stronger bolt that goes through (not welded) and one small hole to grease the bolt, and that it!. I will do the same in the near future, but I do not not understand why Dauntless do not design this part like this in the first place!!!. I hope Jay will jump in and will join this thread and give us his expertise.
Didier
Originally written by twintwin on 5/16/2007 3:56 PM
Thanks guys for your expertice and advises. Now look at Ara blog, and you will see the new mounting bracket for the bolt. One plain scare piece of metal drilled in the center, one stronger bolt that goes through (not welded) and one small hole to grease the bolt, and that it!. I will do the same in the near future, but I do not not understand why Dauntless do not design this part like this in the first place!!!. I hope Jay will jump in and will join this thread and give us his expertise.
Didier
Yes, that looks like what was needed. hope it holds for them.
