Removing center crossmember

[Jeff M]

I need to remove and replace my center crossmember on my 30 coupe frame. Should I just weld some square stock across frame close to the crossmember to brace it? Any tips on removing the rivets? Thanks.

[40-A Twins]

Whenever removing frame rivets, I center punch the rivet head and drill just larger than the rivet diameter, stopping when the head comes off and before drilling into the frame. If the drill was not centered quite right, a cold chisel may be needed to finish shearing off the head. Then use a straight punch to knock out the rivet. I think those rivets will be 3/16".
I don't see any need to brace the frame before removing the center cross member.
Kevin

[katy]

Years ago, while in the scrap metal business, we used a wide cold chisel and a BFH to remove rivet heads. Hit once or twice and the rivet heads just popped off.

[Phil Brown]

Once you have the head off I have always drilled the center of the rivet about 3/4 of the way through to let the rivet "relax" in its hole (they expand tight when bucked up during instillation) insert your punch into the partially drilled rivet and use that last undrilled portion to drive it out.
I would rather tap the rivet out than beat them out

[Jeff M]

Thanks for the tips!

[rotorwrench]

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It's important to have good quality drill bits in sizes that allow a person to choose a size that is no larger than the original shank diameter. I use cobalt bits for steel rivets. Center punch the rivet head as close to center of the head as possible. Drill through the head but try not to drill too far down into the shank. Use a pin punch the same diameter as the rivet shank and place it.in the drilled hole. Pull the punch off to the side and the rivet head should pop off. Use a chisel if it won't pop off. Drive the remaining shank and buck tail out the other side.

The advantage of this method is that if the drilled hole was a bit off center then a person can tell after the head is off. If the shank won't budge then drill farther down while maintaining center. This will keep from elongation the holes. If the holes get too large or elongated then it will have to be welded up and redrilled.

Mark your locations well as to where the member is located on the rails before removing it. When fitting the replacement, align it to the marks. If holes don't align then either the rail or the member will need non-aligning holes welded up to redrill them. Install the member with correct size bolts first. Check frame alignment by cross measuring from front to rear on both sides and check rails with a long straight edge for any sign of bend or twist. If the frame checks out OK then the cross member rivets can be installed and bucked while removing bolts one at a time. This will be enough to keep the member in alignment during the riveting process. Check frame alignment again an perform straightening as needed. An I beam, chain, and a bottle jack can be used to affectively straighten a frame. Reinforcement depends on how much it was bent. It's surprising how well replacement members will fit a model A frame. One or two holes might be off but they are surprisingly close in fit when I've replaced them. Others may have different experiences than I so I can't guarantee a good fit in all situations. Be prepared to weld up some holes.

[Oldbluoval]

I always use a ball shaped burr on my die grinder to put an indentation on the top and then center punch. That die grinder can remove a lot of material before going to the drill bit.
Roto is spot on

[rotorwrench]

I use a hand operated belt sander if I need to level the top off a bit. Sometimes it's easier to get at the buck tail than the head so a person has to be more careful with drilling a buck tail. It may not be on center very well.

[Jeff M]

So no bracing is necessary for the center crossmember? I guess that’s only required for removing the front or rear crossmember since it obviously would free the frame rails.

[rotorwrench]

If the cross member flanges aren't bent then they ought to fit up tight with the frame rails. That's why I bolt them up before installing the first rivet. Use clamps to pull any gaps up to snug and the rivet will hold it after it is bucked tight.

[Jeff M]

Originally Posted by rotorwrench

If the cross member flanges aren't bent then they ought to fit up tight with the frame rails. That's why I bolt them up before installing the first rivet. Use clamps to pull any gaps up to snug and the rivet will hold it after it is bucked tight.

I meant welding some steel across the frame to make sure the frame doesn’t move while removing the center crossmember.

[Oldbluoval]

I think all understand what you’re asking/mean.
Seems mine and roto answer is ….no

[Brentwood Bob]

Bolting up the replacement before riveting then follow rotowrench's procedure.

[Jeff M]

Finally took my body off so it’s time to drill. A poster above said the shank is 3/16” so do I need to use a 5/32” bit? The rivet head is 7/16”.

[rotorwrench]

Ford used 1/4" rivets for most of the frame. The holes were drilled or punched to be a bit larger (17/64" on most model A frames except early 1928 frames). If there are 3/16" rivets then use a 3/16" bit but most of those are in the body framing. Use a 1/4" bit on 1/4" rivets. The big ones are in the running board support brackets. They are 5/16" diameter.

[Jeff M]

Thank you

[wuga]

I just removed and replaced my center cross member. I noticed that when the cross member was removed, the frame slightly flared out on the bottom. I jacked up on the bottom of the transmission to take the load off the motor mounts and the frame pulled right in.
Warren

[Jeff M]

Interesting, my frame has no engine or trans in so hopefully it’ll be good.

[Jeff M]

Everything went smooth until the four inside rivets on top of the lower frame rail. You can’t drill these so I figured I could grind the heads off and knock them out. Wouldn’t budge even with an air hammer. Is drilling these from the bottom the best option?

[Brentwood Bob]

Would a right angle drill fit?

[Jeff M]

Originally Posted by Brentwood Bob

Would a right angle drill fit?

I actually tried that but it’s still too tight of a fit.

[rotorwrench]

Sometimes a person has to drill the buck tail and not the head. I center on the buck tail as best I can and then drill down until approximately at the rail level. Use a good cold chisel to cut the buck tail off. Center up on the shank that is left as best as is possible and then drill down through the rail and part way through the cross member but staying mostly centered in the rivet shank. See if it will drive out but don't bend the flange metal of the cross member. Avoid drilling all the way through unless you have to. The frame may have to be flipped over to remove rivets that secure to the bottom flange of the rail.

Rivets expand to fill the hole as they are driven. With 17/64" holes as original, that's quit a bit of expansion. If a hole is well centered but the shank remnants are still in the bore then use a 17/64" bit or an appropriate sized rat tail file to aid in removing the remnants. Some can be stubborn SOBs. The less holes that have to be welded up and redrilled the better.

Rivets were the best way to put these frames together. Riveting allows for the tightest form of security between two metal structures. There is no need for close tolerance fit since they fill the hole tightly and last for many years of use and abuse. Folks put the Model As through hades and back but most rivets held up. Only the front cross members ended up with security problems due to big cracks forming where the front spring seats. Folks would either chicken scratch weld the member up or they would cut it out and bolt in another member. Many of the frame I've come across have bolted in front cross members since they had no way to rivet them and likely didn't care how well it was secured as long as it would get them down the road again. Bolts would only work well if the were reamed to fit a close tolerance and very well secured but rivets are stronger than most bolts of grade 5 or less. When the bolt gets loose, it is a matter of time before the frame would crack or the bolt would shear.

[wuga]

The rivets are too close to the frame rail to be drilled from inside. Grind the bottom flat and center punch. Go up progressively in drill size and then a good hammer and drift. When I reinstalled mine, I drilled all the holes for 1/4" bolts with posi-lock nuts, You don't see them once everything is back together.
Warren