Hot Rods Frame gussets on kick ups. Overkill?

I was looking at a Tribute T that Speedway builds up close at the Hot Rod Hudred and noticed that the frame was smooth. Is a butt weld strong enough on a Z'd frame? I put fishmouth gussets on my last T. Here's a pic for reference.

 

Go ahead and put gussets on it. You know now you always worry about it.

 

Imo , putting gussets on are like "I welded this , but I'm really not sure about my weld"....Do as you wish...
dave

 

overkill is better than underkill...

 

I would as a matter of course. Apart from being mandatory down here it spreads the load and strenghtens that area considerably. It can be done properly and still look good.

 

There's more truth in that than you know....ha ha

 

A couple of sessions in therapy and you'll be good to go

Seriously , leave it alone and get your head around it. A butt weld that is linear has the same vertical load bearing qualities as a butt welded Tee joint [ for equivalent welded area ]

Have a good look under a Car Hauler trailer!
All the cross-members are Butt welded Tee Joints [ to tubing ] and usually the main rails on a dovetail are also Butt Welded.
An overloaded trailed will be subjected to more abuse than a lightweight Hot Rod.

While you're worrying about all this, have a good look at a tubular cross-member on most suicide front ends. A lot of these are butt welded but we don't give it a 2nd thought.

The reason I use cross-members as an example is the poor torsional resistance of ladder frames will put more stress on these joints, than any beaming loads will on a main rail.

The practice of "adding more and more steel to it ,until it looks strong enough" is backward "cowshed engineering"

 

If it really bothers you, you could make 'fishplates'(often called 'doublers') out of 12ga (or even 16ga) in pairs to 'sandwich' the welded joints in question with triangular points directed lengthwise along the frame rails. They don't need to be massive : allow clearances of 1/2" at each end & no more than 1-1/2" on either side of the weld joint in question. If this isn't enough to put your mind at ease, you need to cut the frame apart & re-weld every joint on it YOURSELF, just to make sure it's up to your standards, otherwise you'll ALWAYS have doubts!!

 

If that's the way you feel,you [or anyone who feels that way] should NOT be welding your own frame.
dave

 

I can weld. I TIG everything. I'm not buying a Speedway frame, just interested in their production model. I will build my own.

 

I'm not a chassis builder, but have built several trailers, anytime I've had to breed two pieces together like that, I'd drill the frame with a few holes, fit a box or plates, inside of the rails, leave about 3/16th gap and weld all three pieces together, then fill the plugs.

I'm a decent weldor, but butt welding a frame together.....well have at it, not for me.

It's not over kill, it's a good practice I can live with for an extra lb of metal.

 

^^^^^ This.

 

I think they call this an aircraft splice. Cut slices in the tube to accept a center plate slightly under flush, and then weld the slots.
I've always wanted to try it, it would make a clean and strong joint.

 

When I work on a c-channel frame that is getting a kick up, I will do the kick up prior to boxing.

One fishplate goes on the inside wall of the outside of the frame, the frame gets boxed, and then another fishplate goes on the outside of the inside wall of the frame.

That way, no fishplates show on the outside of the rails.

All of my fishplates are of the same thickness as the frame stock itself, and are both rosette and perimeter welded.

On tube based frames, they get butt welded. Zero failures to-date.

Only two of my customers have died, and both were from cancer.

 

I put fishplates/ gussets on my tube frames , I like a little bit of extra insurance , especially when doing for someone else ...

I think tubing frames are kinda ugly anyway so not concerned about esthetic appeal, seen many old race car frames done in the same fashion ,maybe all those guys" had no faith in their welds" either?

If its a stock channel frame I do the same fashion as gimpy described also

 

There is an argument that if you use a gusset, there will be a stress riser at the end of the gusset that will make the area weaker than the original tube. I don't have TIG so I use stick and punch it in so I know I have full penetration.

 

Here in NZ fishplates on frame joins are mandatory for street certification, regardless of how confident you are of your welding skills.

 

Either the weld joint can be stronger, when done correctly
or the 'fish plate region' when used. Wolfcreek raises a good point.
Always was careful not to undercut...too much.

 

Miter cut tube always poses some issues.
Even more so since guys who can install door casing can get the welder and dog food and door casing at the same store.

The purple joint is faster, easier to get/hold dimensions and stronger.
It's easy to curve the outside corner and knock the cap around it if you choose.

 

Good discussion.

D-Russ, It appears to me that they used a water jet or similar cutting apparatus, and cut the shape they wanted, then assembled the 4 pieces. But in order to make it match flush, it would almost have to be a butt joint at the attachment point. The only option would be if it slipped over the horizontal frame rail.

Maybe, I am not following you?

 

It looks to me that the square tubing slides into that kick-up piece. Maybe only an inch or so. But that helps spread the forces around a bit.

 

Yeah, I had that thought also. It looks like the main rail slides into the kickup, and the kickup is (4)water/plasma cut pieces edge welded together like boxing plates. Idk, then again it's Speedway so...it's probable.

 

you guys can tell something from this?
It looks like the frame is faded via photoshop to highlight the quick change

 

this is what I did

 

Is this the same ?

 

I used to weld frames for a company (not speedway, but they did want to buy us out)
We didnt fish plate, just a small gap and burn it in hot. I've done fish plates for friends, and I like the looks of a lot of these inserts and rosette welds.
If you can WELD then no, doesn't have to be done. But, why not make it a bit overkill while you can.


I never looked at a rod and thought "This car is just way too well built."

 

That looks very similar. What article is that?

 

Depends on the weld or welder I suppose. If it is properly welded and even ground out smooth it will hold fine. I doubt that anyone welding a mass produced frame is certified most factories just hire junkies and winos off the street.

I would probably gusset or fish plate if it were me, I wouldn't probably go crazy with it though.

@31Vicky with a hemi those holes passing through the frame rail need to be healed. You already knew that right?

here is something to think about, pretty near all the sanctioning bodies, drag race, roundy round and etc. require a slug when splicing tubing. A lot of those chassis are built by professionals that are really schooled well in their craft, but they slug anyway.

 

If you can't weld, weld a lot.

There's no kill like overkill.

Seriously though, I'd think an internal gusset or the "aircraft splice" like Roadsir shows would be a great nerve calmer.

 

I only went in hungover on fiberglass days.
Not certified, but accomplished and well trained in the art of melting metals.