welding repairs question

[EdButterworth]

Hi all, I recently bought a lovely 2nd hand Dingo with Briggs and Stratton 8hp engine but noticed the beginning of a crack on the main frame at the back of the kart.

This could be something I didnt notice at the time I bought it or brought on by larger adults using it - I'm 15stone and have probably driven it for an hour in total over the past 2 weeks.

Either way - attached is the photo - could anyone recommend the best way of applying some preventative maintenance in the form of welding a collar around the crack or merely welding over the crack - what is the best practice to strengthen this kind of issue?

I'm new to the hobby so not sure if this is a regular type of problem or due to too much adult use - any advice here would be hugely welcome.

thanks, Ed

 

[landuse]

Hi there. Usually when you weld 2 sections back together, you try and get a sleeve that will either go over or inside the 2 sections. You can then weld them up like the pic for stremgth

 

[firemanjim]

Unfortunately for you can not do as landuse suggested. The spot where your crack is, well, just won't allow the plug and weld method. Without seeing a bigger picture, my best advice would be to grind the crack clean and touch up with a welder. Then add a bit of plate steel from that tube to the bar/plate next to it..... To help support/distribute the weight/shock load.....
Post a bigger picture....

 

[landuse]

Unfortunately for you can not do as landuse suggested. The spot where your crack is, well, just won't allow the plug and weld method. Without seeing a bigger picture, my best advice would be to grind the crack clean and touch up with a welder. Then add a bit of plate steel from that tube to the bar/plate next to it..... To help support/distribute the weight/shock load.....
Post a bigger picture....

You are right. Looking again I see they are not seperate pieces. If you were really creative I am sure you could do it though

 

[EdButterworth]

thanks guys - the crack doesn't actually go all the way around but its certainly enough of a warning to do something about it. I dont have any welding equipment myself so part of my plan is to find a local guy who could help - hence why any "best practice" recommendations are really useful.

Thanks again, Ed

 

[firemanjim]

Oh it IS possible, but I'm not sure if the OP has the skills/tools to do so. You could cut the flat bar loose from the tube. Cut the tube at the weld.
Here is where it gets a little difficult...... Cut a 1" long piece of round stock that will fit inside the tube, but freely,not wedged. Take a ratchet strap from the left half and secure it to something solid in the front of the kart. You need to have a good straight line, because when you tighten down on the strap, you don't wanna mess anything else up. Now you got it strapped, tighten a little till you see that tube move a LITTLE. With a prybar, pry the right side away from the left, but pushing towards the REAR of the kart. You might need help.... Get the slug ready and give the tube a good heave ho....... And slip the slug in. In know this is possible asbi did it just a couple weekends ago on one of the four karts a customer brought me.
Once you manage to get the slug inside, release the other Tobe and get them as lined up as possible. Center the slug by sliding it over using the tip of a small flat blade screwdriver or pocket knife. Weld it back together making sure you penetrate the slug good. The slug should be about 1.5" but just a little harder to squeeze into a little gap.....

 

[andrewmacc]

I'm on my phone so no long messages, but if you end up not cannibalizing it and sleeving it, drill each end of the crack first, then weld the crack out. Drilling the start and stop of the crack helps prevent crack propagation.

 

[OzFab]

I, too, would like to see a slightly more distant pic, there are obvious signs of previous repairs here & I want to see exactly what the POs have done... that will give us a better idea of how to fix the whole problem, not just part of it...

 

[zbuck]

I am with Fabroman on the previous repair. Looks like someone has put a lot weld in that area. At least remove the paint from that area and then post another picture. It will give us a better idea on helping you repair that area.

 

[redsox985]

I'd remove the paint, drill the ends like mentioned above (this removes sharp corners that concentrate stress), and then wrap a plate (same thickness as the tube or more) over the entire area, and then weld it on as if it were a number plate or something.

If it's already cracking, welding the crack itself will only make it more brittle.