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Tue Feb 17, 2015 12:44 pm

Morning folks, we just got back from Glamis & managed to break the buggy again. The front beam clamps are welded to the rails @ both the top & bottom & the welds @ the top broke. The Clamps are "Hi Jumper" clamps & they look like cast pieces.

My question is, is there any trick to welding to these? I cant imagine that there would be, but................ I figured I would check before I tried it.

thanks
bob

Tue Feb 17, 2015 12:56 pm

If memory serves me right don’t you have to heat up cast before you weld on it?

Tue Feb 17, 2015 2:17 pm

cast what is the real question

I would expect those to be cast steel since they are designed to be welded, in which case you can preheat a bit to help with weld quality (and if your welder isn't super powerful).

Tue Feb 17, 2015 6:21 pm

It is definitely steel, it just looks really porous, which is why I asked.

Bob

Tue Feb 17, 2015 7:33 pm

Most likely cast steel..... IF the were cast iron they would be brittle and casting would break before actual weld gave away...

If you are trying to repair a previous repair on a initial build, my thought would be there is to much "contamination" in area of welds.. You may have to cut beam clamps off, clean and grind to find undisturbed base metal, and maybe do same to tubes ..

Also maybe adding a gusset plate that ties the two tubes and clamp all together so it "works" all as one unit... If its been repaired previously you also have to consder there is a lot of metal fatigue in area of welds...

Maybe a single gusset plate centered on casting and tubes or 2 plates one on each outside of tube tying to casting (on each side)...

Dale

Tue Feb 17, 2015 7:54 pm

Gussets are definitely on the agenda, not sure if they are going to have the bitchen lightening holes that you put in your picture (LOL), but IMO, its a "gotta do" @ this point.

I have not tried to really look @ it hard yet to see how buggered up it is. Im going to clean everything up & get a light on it & see what it looks like. Im hoping not to have to cut the clamps off, it might cause issues with the steering shaft length, & the snowball is picking up steam........................................

thanks
Bob

Tue Feb 17, 2015 8:03 pm

Bobalos wrote: Gussets are definitely on the agenda, not sure if they are going to have the bitchen lightening holes that you put in your picture (LOL), but IMO, its a "gotta do" @ this point.

I have not tried to really look @ it hard yet to see how buggered up it is. Im going to clean everything up & get a light on it & see what it looks like. Im hoping not to have to cut the clamps off, it might cause issues with the steering shaft length, & the snowball is picking up steam........................................

thanks
Bob

To avoid cutting brackets off all you can do is clean them best possible, and bevel grind into breaks and reweld, and gussets are going to be a necessity to get non fatigued steel "connected" at all points...

What size welder do you have ?

Dale

Tue Feb 17, 2015 8:17 pm

I have 110 Mig & a 230 inverter TIG. I dont know if the MIG will be up to this. I can only imagine how much heat that big chunk of metal is going to suck up. I might try to preheat the clamp, before I weld to it, but Ive never done that with something so big (nor a cast piece) so Im not sure what to expect. I kinda dont want to experiment on the thing that holds the front end onto the car that my kids ride in.

Tue Feb 17, 2015 9:02 pm

WHOA!!!! HOLD UP FOLKS!!!!

The front half of each clamp is 356 cast aluminum. The back half of each clamp is flame cut steel bar. It is NOT a casting.

Due to the large difference in thickness between the rear half of the clamp and the wall of the tubing, there really should be plate gussets tying the camp to the ends of the tubes. Hi Jumper's fabricator Kent Brown added them to mine in 1980 after my car broke when I hit a 2-1/2 foot diameter boulder at Barstow's Stoddard Wells during a race. It should be welded with a MIG welder of 220 volts and at least 175 amps.

Tue Feb 17, 2015 9:07 pm

Or a tig welder using one of many acceptable filler rods. For welding the thicker peice to a thinner tube a tig will actually give better control and resulting weld.

Cast steel, steel plate, not a huge difference there if the cast steel peice is of decent quality. Cast iron is of course a different story but the difference between welding cast steel and plate of the same alloy is minor

Tue Feb 17, 2015 9:08 pm

dustymojave wrote: WHOA!!!! HOLD UP FOLKS!!!!

The front half of each clamp is 356 cast aluminum. The back half of each clamp is flame cut steel bar. It is NOT a casting.

Due to the large difference in thickness between the rear half of the clamp and the wall of the tubing, there really should be plate gussets tying the camp to the ends of the tubes. Hi Jumper's fabricator Kent Brown added them to mine in 1980 after my car broke when I hit a 2-1/2 foot diameter boulder at Barstow's Stoddard Wells during a race. It should be welded with a MIG welder of 220 volts and at least 175 amps.

Ok. I'll buy the flame cut steel concept.....Got any pics of your gussets..

Dale

Tue Feb 17, 2015 9:24 pm

Yeah...Prints.
That I would have do dig through thousands of prints to find.

MAYBE IF I have time tomorrow, I MIGHT take some pics and share them.

Wed Feb 18, 2015 6:49 am

Richard,

that would be awesome if you could put up a picture of how you did yours.

thanks
bob

Wed Feb 18, 2015 9:39 pm

Life didn't allow me time for that today. If I remember tomorrow, I expect to have the time. Friday I have to take my wife to physical therapy and then we're taking off to the Battle at Primm offroad race.

Thu Feb 19, 2015 4:19 pm

OK...I finally got to take some pics of the gussets on the beam clamps on my Hi Jumper Ascot.

The gussets are made of 3/16" cold roll plate with a 1" flange formed on the back edge of each. They are welded full circumference to the beam clamp and to the frame rail tubes.

I feel they present a stress riser at their back edge. I wasn't happy with them when I went to San Fernando Buggy to pick up the car when they were installed. But they were done and I didn't have time to have it done over before the next race, so I decided to change it when it failed again. There has never been any cracking since then, so it has remained like that for 35 years.

If I were to do it on another car, i would do it more like the gussets I put on my 58 Baja myself.

This pic from during fabrication is a little tough to see clearly due to rust and weld coloring and such. So lets try iut with paint and maybe it's more clear to you.

Note how the ends of this gusset are tapered into the tube. This makes for a more gentle transition from unsupported tube to strongly reinforced tube, while dramatically increasing the weld contact area between the beam clamp and the frame rail tubes. It also allows for 10.25" of wheel travel with the stock steering box (yeah...I know - MASSIVE bumpsteer) while clearing the tierods throughout the wheel travel and steering cycles. The means to reinforcing the junction of beam clamp to frame rail tube these days is to sleeve a section of 1.75" x .120 tube about 6" long over the frame rail. That needs to be done with the end of the sleeve cut at a severe angle 30° from the tube axis to prevent creation of a stress riser.

FYI... "Stress riser" means a place where there is a dramatic change in stiffness of a structural member. This dramatic change causes forces to be concentrated right at that point and makes that point by far the most likely place for failure. In some cases, it makes that point more likely to fail than if the reinforcement were not there at all.

BTW...This gusset works for the separate type beam clamps too. That's what is on my Baja Bug. For any Baja or buggy that's going to be used for hard offroad, the upper and lower tubes should be tied together with a tube and/or a plate gusset. My buggy won a championship with the beam clamps as shown in the pics above and 30+ years of play use since then. The Baja has been used for years of hard, drive it like you're racing pre-running on the roughest offroad race courses there are. Neither has cracked or broken with those gussets.

Thu Feb 19, 2015 8:11 pm

DustyMojave,

thanks for the great pictures. that gives me some good idea's. I appreciate the information about the stress risers, things I dont know.

that is a heck of a cool Baja.

BTW, what exhaust is this?

Fri Feb 20, 2015 5:33 am

That looks like the Empi knockoff of the Tri-mill Bobtail.

Fri Feb 20, 2015 7:21 am

Gotcha. I should have known that Tri-Mill would have something. Im looking for something lower than what I have now. Im hoping to keep it under the hight of the doghouse/filters.

thanks
bob

Mon Mar 02, 2015 9:21 am

I got quite a bit done this weekend. gave the welding helmet a little tuneup & WOW does it make it a lot easier to see what Im doing.

I cleaned everything up & welded the clamps back on the upper bars & put the gussets in on EA side.

I put new lenses into it with a cheater 1.5 lens inside & a new REALLY bright light on the top & boy does it make it a lot easier for me to see what Im doing.

thanks again for all the help guys.

Bob

Mon Mar 02, 2015 9:50 am

I like this...

That's what I did to my welding helmet....I used one of those LED head lamps and it makes a whole lot easier to see where I need to put the weld.....

Helmets should come equipped with lights just a some diving helmets...

Maybe even like cave explorers...

Dale