Now I am on crack!

[Mex-Busnut]

Dear friends,

Today between two long visits to my dear ailing mother, I went to check on my friends that are working on my bus. The entire floor is now out. I discovered something perturbing: I have a full crack, plus another hairline crack in one of the crossbars that support the front of the Torsilastic suspension! These are visible in the picture, just to the left of the red wire, and directly below the two bolt heads.

My welder friend came over to look at it, and said he can fix it with his 220-volt, 80-amp welder. However, we want to know if it might be better to add some kind of reinforcing plate to this? Suggestions?

What would cause this to happen, and how to prevent it from happening again?

I do believe all the Torsilastic suspension components look like they could use a real good cleaning. (30 years old!) How do you lubricate it? Tomorrow we will give the other end of this suspension a good checkup.

[Chopper Scott]

Just make sure you v the cracks out good before welding them and plate over the top and bottom if possible. Do not weld across the ends of the plates in the same direction as the current cracks or you'll have cracks again. Try and get the plates to go far enough to get to other framework if possible. An 80 amp welder is pretty small even if it is 220.

[Mex-Busnut]

Thanks, Chopper! Please excuse my ignorance and explain: "v the cracks out good".

Thanks again!

[babell2]

What Scott is saying is to grind a V grove in the crack to allow the weld to penetrate to the full depth of the frame member being welded.  During welding the thickness will be replaced by fresh weld and penetration of the weld will be complete to full depth.

Brice

[bevans6]

Good catch!  Boy, those are nice.  Classic frame cracks.  As stated,  grind the cracks full depth.  I don't think an 80 amp welder is enough, I would hesitate with my 170 amp  220 volt welder but I would probably do it.  I wouldn't touch it with an 80 amp welder.  The amps refers to the DC amps at the electrode, not the amps drawn from the supply, btw, so the 220 volt part is kind of moot.  You really need a good welder (person with experience, not welder machine) to do this, and I would plate across the whole member with .100" plate.  A really good operator can make a decent if small machine stand up and do tricks that a rookie can only dream of, and I know that you have great operators in Mexico.

[chev49]

besides the above mentioned, i would use a really thick stuff  like maybe c channel the right size and drill a buncha holes for plug welding as i was welding the thing on.. but i like overkill. and make sure all metal is properly cleaned before welding.

[robertglines1]

you know being in Mexico and using that word : you never know who is lurking.  Just kidding. Sounds like you have it covered. Clean - V -reinforce =better than new.  take time don't overheat surrounding area.

[belfert]

I would be a bit worried about how the metal cracked in the first place.  I wouldn't imagine Mexico uses salt so it probably didn't rust too bad.  I've hard that Mexican roads are really bad so maybe it just broke from the roads.

[Mex-Busnut]

I would be a bit worried about how the metal cracked in the first place.  I wouldn't imagine Mexico uses salt so it probably didn't rust too bad.  I've hard that Mexican roads are really bad so maybe it just broke from the roads.

That is what I want to prevent from happening again. Yes: We have some great roads and some terrible ones. Any preventive ideas are appreciated!

[Brassman]

Only an expert could repair that in place. Cracks are like mice: see one, there's more.

[demodriver]

Usually a crack that has been welded up will recrack some where.   

How long is the piece of tubing? Is there very many brackets on it?
The reason I ask is because if it was mine I would like to change the whole tubing and add some braces.

Is there a reason that the piece was over stressed? Bad suspension parts? Or is it just fatigue from age?

Eric

[Chopper Scott]

Take it too a welding shop and let them do it right. Nothing against your buddy with his little welder but he really probably doesn't have a clue or he'd give you the same advise. If it's easy access and I'm not laying on a piece of cardboard trying to weld up the underside, (I add for burn't scars on my arms!) I would think 2 or 3 hours tops. If you bring it to me after your buddy welded it up it would probably be more like 5 hours and even more scars on my arms!!! Buddies can cost you a lot of money unless they do stuff like this for a living.

[Chopper Scott]

Usually a crack that has been welded up will recrack some where.   


Eric

Not at my shop!

[chev49]

Yeah, part should be removed... and no telling what else you would find... orig part needed to be stronger in the first place.. thanks to the engineers ,... and you could build a new one 3 times stronger.. but it would help to have some professional equipment as stated in the previous threads, cause it's hard to build things without real welders, grinders, plasma cutters, lathe and the like

[Lee Bradley]

Plenty of rust in the sheet metal to the right and looks like that beam is rusted out at the bottom between those cracks.  I would replace the beam.