Boxing the frame

[BLZN4FN]

How did you all box or stiffen your frame? Did you do the whole frame or in sections? Also how thick of steel did you use and anyone have any pics on how it turned out.

 

[cybrfire]

Boxed the whole thing, bumper to bumper. Sections at a time though. 10ga.

 

[Hogback Fabrication]

I plan on doing certain parts of the frame and using steel plate similarly sized to the stock frame (1/8" in my case, I think).

 

[454k30]

never did myself however I helped a guy do it to his '79 frame. boxed it from front to back with 1/4. While reassembling the truck it was obviously a much heavier beast to deal with and running the wire looms, brake and fuel lines were a pain! If I could do it myself I would still box the whole frome but I would drill and dimple large holes all the way along it to avoid the huge gain in weight and problems with plumbing and wiring. Off road the frame didnt move much at all though so It was worth all the trouble, also the boxing itself was pretty easy.

 

[BLZN4FN]

I plan on doing certain parts of the frame and using steel plate similarly sized to the stock frame (1/8" in my case, I think).

What parts are you thinking?

 

[cybrfire]

The problem with doing only parts of the frame is the frame will then have the tendency to crack at the end of a boxed section. You'll significantly strengthen one portion of the frame, all the flex will end abruptly right there. Stress riser.

No real need to go with anything heavier than the parent metal. This case being 1/8" or 10ga. (close enough). It's not the thickness your after but the added wall completing the box tube. Now, when you put your crosmembers back in, try to run them completely through the boxed frame.

 

[RGV72BLAZER]

Boxed the whole thing, bumper to bumper. Sections at a time though. 10ga.

this is what i'd do if i had the patience


however, due to time constraints, & lack of patience, i decided to just box around the x-members and leave the ends open. stiffened the frame up a lot more & once we get the cage done, i'm sure we'll have more than enough rigidity.

EDIT: i used 3/16"

 

[Hogback Fabrication]

What parts are you thinking?

At the very rear of my frame:

The distance between the crossmember I made and the rear most crossmember (probably the second rear most crossmember on a stock frame, I cut one off). I will also add square tubular gussets in this area because I plan to add D-ring mounts in that last crossmember and I don't want anything failing.

In the middle:

Most of the flat, center part of the frame. You can hit a lot of this part of the frame on rocks and bend the crap out of it (sound familiar?)

I have additional plans for the following because the main part of my chassis ties in here and I plan on a 4 link soon:

I plan to run short pieces of 1/8" plate perpendicular to the frame (side to side, I guess) at each critical point on the frame. These include the three places the "cage" connects to the frame and two (one at each end) for each link bracket.

To clarify, lets say that my frame is 4" tall and 2" wide (just guessing). I am talking about getting a bunch of 2"x4"x1/8" pieces of plate and welding them to the frame at the places listed above and then boxing the frame over those (the plate that is used to box the frame will need to be cut into several sections to assure that all of the steel is welded to everything).

I don't know how well I described this, but basically adding these extra little supports keeps the frame from collapsing in these areas. I don't want the 4 link brackets to bend the frame in or out. I don't want a hard roll to ruin the frame either. Older Chevy frames are pretty flimsy and they can use all the help they can get.

If you don't understand what I'm saying, I'll make some drawings.

The front:

Basically everywhere I think I can get the plate to fit. I have some issues with the chassis not being stiff enough in the front and I think I am going to plate as much as I can without taking everything apart.

 

[Hogback Fabrication]

The problem with doing only parts of the frame is the frame will then have the tendency to crack at the end of a boxed section. You'll significantly strengthen one portion of the frame, all the flex will end abruptly right there. Stress riser.

No real need to go with anything heavier than the parent metal. This case being 1/8" or 10ga. (close enough). It's not the thickness your after but the added wall completing the box tube. Now, when you put your crosmembers back in, try to run them completely through the boxed frame.

I get that too, I would only avoid areas that I already felt were rigid from the chassis.