Best method for removing rivets

Rockymountainsparky

Senior Member
I noticed that the front cross member on my 36 3 window coupe is rotted out and missing the steel material where the spring gets u-bolted to it. I found a NOS cross member and am now ready to replace it. My question is: What is the best way to remove the rivets? I plan on replacing them with Grade 8 bolts.
 
A die grinder and high speed cutting wheel for metal works fine. Take your time and grind off the head of the rivet. Drive out the rivet with a hammer and punch.
 
I had a front crossmember with a large crack in it on my old '36 3-window. I replaced it with one from Precision Coachworks, who, unfortunately, is no longer around. It was a perfect fit. Since I was unable to do riveting, I used Allen Socket-head cap screws to attach it. They are at least grade 8 and plenty strong enough. I used Centre lock nuts and Loc-Tite to attach it. When I was done, I filled the Allen holes with body filler and sanded them smooth. The result is they looked just like rivets. I drove the car another 4 years before I sold it, with no problems at all. The last I heard is that the current owner is still driving the car.
 
I like to grind a flat on the head of the rivet, then center punch head, drill a hole slightly less then the rivet diameter to the depth of the head and first layer of metal, switch to a rivet diameter drill, drill thru the head thickness, knock the rivet's head off, then take a pin punch the diameter of the first drill and drive out the rivet, supporting the back as needed.

When the rivets were initially installed, they swelled to fill any misalignment between the layers being rivetted.

Works smooth and eliminates deforming the parts and is less frustrating than excessive pounding.

If not installing the crossmember with rivets, I usually choose bolts with unthreaded shanks close to the length being fastened, shortening the excess threaded length, drilling (or reaming) the holes for a tight fit, and lightly driving the bolts in place.
 
Ok, here is what I do. Get a short length of 1/2 " x 1" flat bar. Measure the head of the rivet and after drilling a 1/4" pilot hole in the bar, drill a recess in the bar deep enough so the bar neatly sits over the head of the rivet and flush with the surrounding metal. Clamp the bar with a couple of vise grips and drill a 1/4" hole right through the rivet. Remove the bar and gradually open up the hole until you just break through the side of the rivet. Only drill deep enough to just get past one thickness of the cross member. Now get the biggest punch, or a long bolt that will fit in the hole and bash the rivet apart.
 
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I use an air chisel with a sharp flat bit to knock the head of the rivet off first, they sometimes pop off easily others take a moment to. Sometimes I can then punch it out using a pointed air chisel bit. If its stuck in there then simply drill and once you have thinned it down most of the way punch it out with a hammer and drift.
 
My dad worked out at Kaiser Steel, a WWII steel making plant. He taught me how to take rivets out. Grind the rivet head down until its turning red. That's when the head is just paper thin, stop grinding before your grinder breaks through it and touches the frame rail. Then center punch the rivet and drill it but do not drill all the way through it, just enough for the bit to make it through frame rail. Drill out most of the rivet but do not use a bit big enough to accidently drill into the frame. When the factory rivetted them together the rivet was red hot and expanded into the hole tight. You need to relieve that expansion by drilling the rivet but without hitting the frame rail. Use a bit a couple sizes smaller than the rivet, maybe a 1/8" smaller than the rivet. Since you did not drill through the rivet all the way it's left you something for a punch to rest on, a couple strikes of a hammer, and it will pop out and leave a pristine unmolested frame hole. I Hate Butchered Torched Rivet Holes, there is no reason for it.
 
I've drilled so many rivet heads and buck tails the I can't even count all the projects any more. Getting centered is the most important thing move the drill to keep it centered if you have to. Use a bit that is the same size as the rivet and have a punch of the same size to break the head or tail off before further drilling if needed. Use an automatic center punch or a punch with light tapping. If the rest won't pop out the drill some more until it does. Try not to drill all the way through unless you have to. Use the best bits you can afford. I use cobalt after the high speed steel ones get too worn down. I learned to sharpen them a long time ago but a bit can only be used till the central spine is too wide which makes further sharpening impossible.

Wallered out rivet holes should be welded up or patched and redrilled. You might think patching is crazy but I'll patch a hole before welding it up in some cases. Making little patches is a pita but some holes are too big to weld up and I don't like using filler rod if I don't have to. I use an aircraft gas torch to do all my sheet metal welding.
 
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I had a front crossmember with a large crack in it on my old '36 3-window. I replaced it with one from Precision Coachworks, who, unfortunately, is no longer around. It was a perfect fit. Since I was unable to do riveting, I used Allen Socket-head cap screws to attach it. They are at least grade 8 and plenty strong enough. I used Centre lock nuts and Loc-Tite to attach it. When I was done, I filled the Allen holes with body filler and sanded them smooth. The result is they looked just like rivets. I drove the car another 4 years before I sold it, with no problems at all. The last I heard is that the current owner is still driving the car.

As you have detailed your concern for the longevity of the faux rivets, you must have heard of the failure of bolts in place of rivets on cross-members. Perhaps you can relate a couple of horror stories?
 
As you have detailed your concern for the longevity of the faux rivets, you must have heard of the failure of bolts in place of rivets on cross-members. Perhaps you can relate a couple of horror stories?

I have not a one; just many miles of pleasant motoring. It sounds like you may have had some bad experiences, though.
 
Not with auto frames, but I’ve seen wallowed out holes from mismatched bolts, and sheared bolts where taper pins should have been used. There’s a reason why bridges and skyscrapers are constructed with hot rivets, I just thought you may have a couple of stories for us.
 
I riveted my front cross member in my 35 coupe when I was a strong young ladd about 12 years old. My dad got home from work about 630 in the evening and i just had to show him what i did, he was not pleased, called me all sorts of stupid, but its still there and working great, I'm 77 now
 
QUOTE=ford38v8;2444926]Not with auto frames, but I’ve seen wallowed out holes from mismatched bolts, and sheared bolts where taper pins should have been used. There’s a reason why bridges and skyscrapers are constructed with hot rivets, I just thought you may have a couple of stories for us.[/QUOTE]

Oh, OK. I thought you might have had some meaningful experience.
 
Stogy from the HAMB helped me (actually he did most of the work) recently drilling out probably close to 40 rivets that held the spring hangers to a 1920 Chevy chassis. He’s an aircraft airframe tech. We started with a 1/8” bit, then progressed up a few sizes in steps. Drill just deep enough to get through the first layer of metal. Adjust centre if necessary with each bigger bit. Final drill size should just be a bit smaller than the OD of rivet and drill through both pieces. Once that was done, chisel off the remaining head of the rivet, and then knock out the carcass with a punch. Takes a lot longer, but worth it in the end. We didn’t bugger up the original frame or spring hanger holes following this method.
 

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Stogy from the HAMB helped me (actually he did most of the work) recently drilling out probably close to 40 rivets that held the spring hangers to a 1920 Chevy chassis. He’s an aircraft airframe tech. We started with a 1/8” bit, then progressed up a few sizes in steps. Drill just deep enough to get through the first layer of metal. Adjust centre if necessary with each bigger bit. Final drill size should just be a bit smaller than the OD of rivet and drill through both pieces. Once that was done, chisel off the remaining head of the rivet, and then knock out the carcass with a punch. Takes a lot longer, but worth it in the end. We didn’t bugger up the original frame or spring hanger holes following this method.
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Rotted-out cross member. Wow. That's a massive steel. What/ how? The reason, road salt? Replies welcome. Thank You!
 
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Stogy from the HAMB helped me (actually he did most of the work) recently drilling out probably close to 40 rivets that held the spring hangers to a 1920 Chevy chassis. He’s an aircraft airframe tech. We started with a 1/8” bit, then progressed up a few sizes in steps. Drill just deep enough to get through the first layer of metal. Adjust centre if necessary with each bigger bit. Final drill size should just be a bit smaller than the OD of rivet and drill through both pieces. Once that was done, chisel off the remaining head of the rivet, and then knock out the carcass with a punch. Takes a lot longer, but worth it in the end. We didn’t bugger up the original frame or spring hanger holes following this method.

That's some impressive work with a drill. I have only removed frame rivets one time, and with no guidence whatsoever it proved to be extremely difficult to get them out. I ground off the heads and proceded to (ok, attempted to) drive the shank out with a punch. This swelled the rivet ever tighter into the holes. The end result would not please most of you, but the heads of the carraige bolts DID look sorta like rivets. Thankfully they were just running board brackets.
 
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