A couple weeks back I tore the remnants of the pickup body off of my '52 only to discover a missing cross member. It's the one directly behind and hooked into the rear spring hangers. Someone commented that this is often done to move/add a gas tank but in this case, it looks like it might've been torn out trying to pull something. Then again, they might've cut it out in order to leave the spring hangers secured.

I want to repair the damage and would like to hear from others who have dealt with the rivets used for the frame. It looks like the best way to remove the rivets would be to grind the heads off one side then use a punch to drive them out. Considering how they were put in there and how long they've been in, there's probably a lot more to it than that.

Also - I do have the needed cross members (the spare tire angle iron is warped & stretched too but it doesn't look structurally important) in the '51 donor but since it's a titled vehicle(frame), I'd hate to chop it up worse if someone just happens to have some frame pieces laying around in their parts stash.

Photos below of what I'm talking about and in need of. Worse case scenario - the '51 frame will be ready for a rear-mounted gas tank modification!

 

So far the factory rivets have not been a big deal to get out on my 51. Grind off one rivet head, center punch and drill a 1/4" hole through the rivet and then punch it out. The drill hole gives the metal a place to collapse into, seems to work well to not distort the frame. I have knocked out some without drilling but they come out easier with the drilled hole.
The original crossmember was mounted to the frame and the rear spring shackle, looks like they cut the crossmember on your truck and left the piece riveted to the shackle. I would knock those rivets out as well and then bolt in the crossmember in all the factory points so it pulls the frame together like it was supposed to.

 

I agree with 70SS. I was able to use an air hammer to get the rivets out after grinding off the head on about half of them, the others needed the hole drilled also.

Just pull the rest and bolt in the replacement with some grade 8 bolts and you should be good to go.

 

From the sounds of your post, it looks like you are wanting to return the frame to its stock configuration. However, you may want to consider a mod that is similar to what I did on my 56. The frame rails at the rear of the frame are very flimsy. I was mounting my gas tank under the bed and had no need for the curved spare tire mount/crossmember so I opted to weld in a crossmember at the very rear of the frame. Here are a couple of pics that show how I went about the mod. The frame is now VERY rigid.

 

Sorry for the delay replying.

Thanks for the info, guys. Drilling a hole to allow the old rivet to collapse upon removal is not something I would've thought of, at least not until pounding on a couple of them longer than necessary. I sold off a lot of little-used tools when I moved a few years back, so the Armstrong method is usually the only one available to me at this point. Though I asked Santa for a few goodies to make life easier.

Charlie, that boxed-in frame looks pretty sweet, and would still allow stock mounting of the bumper by the looks. Along with the safety factor of adding back in the support, pulling the frame back together to allow the bumper to be mounted is right up there on my list. It's just sitting in the cab saying 'put me on the damned truck!'.

Thanks again, and I hope everyone had a safe & happy Thanksgiving.

 

Personally I thinik you need the crossmember between the spring hangers, that is a heavily loaded portion of the frame and you need to prevent twisting. If it wasn't needed, you can bet Ford would have left it out.

 

Gotta agree with Ross on this one. But I've mentioned this before. At the very least, some additional bracing in a K member fashion to the spring hangers from the rear crossmember, but that eliminates the gas tank space, which is the reason most guys relocate that member, anyway. Just my 2c.

 

Easiest way to get the heads off the rivets is to use a cutoff wheel to cut an X in the head like two screw slots, being careful not to cut into the frame. Use a sharp cold chisel and hand maul parallel to the frame to knock the 4 pieces of the head off. They will come off surprisingly easy. Use a punch near to the rivet shaft diameter to drive it out. Alternate to punching it out you can use an appropriate sized socket over the still headed end of the rivet and a ball bearing over the cut off shank after removing the head as above along with a C clamp to press the rivet out. Lacking a ball bearing you can use a second socket, a 5/16" x 1/4" drive, and a 1/4" allen head cap screw 1/8 to 1/4" longer than the height of this socket. Place the nut side of the socket over the cut off rivet and stick the cap screw thru the 1/4" square hole in the other end of the socket. This will center the cap screw over the rivet shank and give a stable support for it while you drive out the rivet with the c clamp. Much easier to set up and use than describe! Pressing them out will not bend or distort the frame. If the description doesn't make sense email me and I'll send you a sketch. Replace the crossmember using 5 or 8 point bolts, washers and lock nuts.

 

Since your parts truck frame has been cut up in the front I wouldn't hesitate to use the crossmember out of it.

 

Here is my home made rivet punch, just knocked out 6 rivets with it a little while ago. Bolt is from a 1982-2002 camaro or firebird that bolts the torque arm to the rear axle housing. Long enough to keep your fingers safe and works great with the mini sledge. I just removed that crossmember you are missing and relocated it to the rear of the frame for gas tank clearance. I have longer than stock leaf springs so moving my crossmember to the back actually helps.

 

I like the punch, Dave. Low tech and functional!

Sorry for not being clear Ross, but yes - I will be replacing the missing member. That's a non-negotiable, especially with the spring shackles right there. I'm not adding a tank or anything that requires it be missing, or otherwise reinforcing the frame, so it will go back in. I like Charlie's boxed back as it would tidy up the twisted and bent/distorted frame ends.

Ax, I've got a fellow stopping by later today to take a look at the '51 parts donor truck but he already knows that the rear cross member will be removed for my project. Since it will end up as a hot rod if not parted out, it won't matter to him. He's actually offered to remove it for me.

Just another unexpected surprise(delay) waiting to be found when I took the bed off.

 

Boomer, those frame rails are pretty flexible and it doesn't take much work at all to bend/move them back to their correct position again. Don't fret too much over that.