Front cross member fracture help

ModelADrew

ModelADrew

Junior Member
Can anyone give some advise on what to do about this cross member. Replace it or fix it, where to get one, how to remove the old one, are they riveted in or welded? Thanks,
 

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They can be repaired, either by riveting a doubler in, or welding the cracks, or replaced. They were originally riveted in, hopefully for you, someone hasn't welded it in. My preference would be to replace the old with a good one. Make sure you get the correct one for the year of your car. The radiator pad is different between the 28-29 and the 30-31. A 30-31 can be used in an earlier chassis, with some spacers added for the radiator, but a 28-29 cannot be used in a 30-31 as the radiator will sit too high.
 
It can be fixed. The question is, are you up to fixing it. You need to get a good look at it in its entirety. They are normally riveted in. To really see all that's involved you will have to remove the fenders.
 
Deep V and a good fill weld will work fine for years. Call Bert's in Denver for another one is you would feel better with no welds on the member.
 
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When I sent my motor in for rebuilding, I knew I had to deal with a similar crack in my front cross member as you that I had been watching for many years. I really didn't want to deal with replacing the cross member so I called a mobile welder out to my house to weld it up. Just remove the spring clamp for better access. The welder will V out the crack with his grinder and fill it. All those years of worrying about it were remedied in about ten minutes.
 
IMHO if you read in past threads about replacing, riveting the member I think you will chose to have it welded. My question is WHAT caused it to crack in the first place and maybe keeping it from cracking again! Would loose spring U bolts? Bad fitting of the springs? Years of driving with out shocks?
 
Weld it, I had mine done in May. Remove everything around the crack so the welder can get at it. He tig welded it.
 
Make sure the original rivets to the frame rail are installed properly. Mine wasn't cracked but had been replaced in a horrible manor - stove bolts, bent over rivets and miss drilled holes and a couple empty holes. If that may be the case replace it.

John
 
It has been my experience that even after you weld repair a front cross member it will just crack again, and again. I would replace it with something solid and uncracked. I have a few front cross members should you need one. I would need to know the year of your car though.
Best,
Dan Bixby 816-213-8437 mbixbys@msn.com
 
About the Question,"why did it crack?" My guess is that the front springs working like it was a solid mass and not able to flex and slide, one leaf over the other. Then the absence of functioning shocks comes to mind. Many threads on limbering up rusted,dry spring packs. May be a little saggy afterwards but a good learning experience until the decision is made to replace with new.
 
High Drew,

From experience in knowing all of the previous owners who cracked my front cross member.

1. The terrible vintage roads and field dirt roads that made front cross member crack can only be found if you look for some non-classified roads in the boonies, not properly labeled by a Highway Department on a map.

2. The rough wild drivers who made this front cross member crack can be found in 2016 among wild drivers, (some drunk, some sober), who have absolutely no respect for preservation of these wonderful vintage cars.

3. Get it properly welded by a professional welder and with normal intelligence and care, you will probably wear out (5) sets of piston rings before it cracks again.
 
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ModelADrew,
Replacing the front cross member is a big deal.
We did it on a members frame on a table where we had access to all sides of the frame. One member designed an offset anvil so the rivets can be bucked hot. There are rivets on all sides of the "C" channel and we found that not all the holes lined up and some had to be welded up and re-drilled. I would really try to have it welded with doublers added where they won't interfere with anything that needs to go back in.
Think it through before you make a decision.
Al Leach
 
billy myers said:
cut the whole section out fit with new metal tig weld in
Click to expand...

X2. the car that I am working on had a repair plate that looks like it was stick-welded in by Stevie Wonder (its sitting on the passenger frame rail in the picture) :p

I cut the repair plate out and TIG welded in a fresh plate. though I had to MIG about 10% of it due to crap in the metal that just popped and hissed at my TIG torch

I measured the metal as 5/32" thick...
 

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Why did it crack? Probably metal fatigue combined with some pretty rough roads and almost-roads over a lot of years. Not a lot of city driving and probably owned by country folks who went where they had to over bumps and through chuckholes. Here is a photo that shows just how far the two solid axles and frame can twist and on rough roads they twisted a lot. Those two fairly close together bolts that held the spring to the front crossmember concentrated all the leverage of the axle into one small space, straining the metal until it finally broke with one big bump.
I think.
 

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Like mentioned above, call Bert's in Denver to get a replacement. I replaced both of my 29's. I used good bolts to bolt it in rather that rivets. So far no problems with this method but if you are doing a show car, then you would need rivets.
You may also find a good replacement on this site or on EBAY.
 
Fred K-OR said:
Like mentioned above, call Bert's in Denver to get a replacement. I replaced both of my 29's. I used good bolts to bolt it in rather that rivets. So far no problems with this method but if you are doing a show car, then you would need rivets.
You may also find a good replacement on this site or on EBAY.
Click to expand...

Note: Don't bolt in the crossmember. It interferes with fender fit. The fenders will not sit down on the frame properly. The frame top 6 rivets are countersunk.
See the right side of photo in post 15.
 
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I riveted mine in alone using 3/4" nut connectors and needed length 3/4" bolts to back up the horizontal channel rail rivets with the heads on the inside. The horizontal rivets in the vertical channel I backed up with steel blocks and clamps. I heated the tails until they were red hot with torch in one hand and small ball peen hammer in other and went to work - tails should be 1 1/2 diameter before bucking and 1/2 diameter after. The top 4 rivets only need about 1 diameter lenght to fill the counter sunk hole - file off any excess height. Takes quite a bid of trial and error to get each rivet set solid with the connectors and blocks. I did several samples with this method then cut vertically through the rivet and they were all firmly solid in the hole with no gaps. Correct rivet oreintation probably can't be obtained for points. It is a must that the heads are very solid against the member before heating and bucking. I am much more comfortable with this method than trying to put a round bolt in a "unround" hole. The round head rivets had a flat spot about the diameter of a BB

John
 
My brother's 30 coupe had so many cracks in the crossmember we couldn't weld it back together, it was all ready to crumble. We changed the crossmember to a good used one and bolted in with grade 8 hardware, that was 10 years ago and as far as I know it's holding up well.
 
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