Classic Mustangs (Tech) Technical discussions about the Mustangs of yester-year.

Trunk brace welding

Thread Tools
 
Search this Thread
 
Old May 1, 2011 | 10:31 AM
  #1  
LynnBob Mustang's Avatar
LynnBob Mustang
Thread Starter
5th Gear Member
 
Joined: Aug 2007
Posts: 2,243
From: PA
Default Trunk brace welding

I've got my trunk brace out of the '65 and I was thinking when I install it that I will bead weld it back in instead of of spot welding it back in. I'm not looking to be original, just safe, functional, and get the job done. Most everything will be covered in seam sealer when done anyway, so looks won't matter.

Any pro or cons for either?

I'm realizing more and more just how cheap these cars were made the more I rip it apart, I'm thinking the bead welding will be stronger in the long run.
Thanks for any tips.

Lynn
Old May 1, 2011 | 12:49 PM
  #2  
2+2GT's Avatar
2+2GT
6th Gear Member
 
Joined: May 2009
Posts: 5,232
From: PA
Default

Yeah. A beat will be on the edge of hem on the panel, but it was designed to welded inside the hem. What you propose would be weaker than the factory spot welds. Use rose welds with your MIG. The trunk braces should be welded all the way through to the frame rail, or they will just be decorative. I'd hate to see your bumper held on by something decorative.

Old May 1, 2011 | 12:57 PM
  #3  
bent metal's Avatar
bent metal
2nd Gear Member
 
Joined: Aug 2010
Posts: 197
From: ca
Default

Are you guys talking about the trunk brace, or the bumper brace?

Any pictures to show exactly where you are refering?
Old May 1, 2011 | 04:14 PM
  #4  
LynnBob Mustang's Avatar
LynnBob Mustang
Thread Starter
5th Gear Member
 
Joined: Aug 2007
Posts: 2,243
From: PA
Default

Originally Posted by bent metal
Are you guys talking about the trunk brace, or the bumper brace?

Any pictures to show exactly where you are refering?
I'm not talking about the bumper braces.
Over all pic.

I'm talking the trunk brace where it is mounted in side the trunk and the trunk floor edges.
You can see the one spot weld that held the tab on the trunk floor that was attached to the trunk brace here..


You can see where the two spot welds on the tab where the trunk floor was being held on by two spot welds to the trunk brace.


You can see where the trunk floor edges are beat up from getting the trunk brace off the the floor as well.

It is those areas where I'm talking about using bead welds instead of spot welds.

Lynn
Old May 1, 2011 | 04:18 PM
  #5  
LynnBob Mustang's Avatar
LynnBob Mustang
Thread Starter
5th Gear Member
 
Joined: Aug 2007
Posts: 2,243
From: PA
Default

Originally Posted by 2+2GT
Yeah. A beat will be on the edge of hem on the panel, but it was designed to welded inside the hem. What you propose would be weaker than the factory spot welds. Use rose welds with your MIG. The trunk braces should be welded all the way through to the frame rail, or they will just be decorative. I'd hate to see your bumper held on by something decorative.
I understand what your saying. I'll fill the spot welds back in, as those holes need to be fill in anyway, when I attach the brace to the floor and do a bead as well.
Lynn
Old May 1, 2011 | 04:41 PM
  #6  
2+2GT's Avatar
2+2GT
6th Gear Member
 
Joined: May 2009
Posts: 5,232
From: PA
Default

Ah, the rear crossmember. Definitely rose weld. Between the crossmember and taillight panel, and especially through the crossmember to the frame rails.
Old May 2, 2011 | 10:49 AM
  #7  
bent metal's Avatar
bent metal
2nd Gear Member
 
Joined: Aug 2010
Posts: 197
From: ca
Default

I'm no "pro". I've only done one Mustang. So "2+2" would know better then I would. But you might want to get the new pieces before you decide what to do. I know when I did that area on my project I had to move those brackets to make them line up with the tail light panel. But mine was all new stuff. Your trunk/bumper brackets are original, so they should be in the right place already. Still, I think it would be smart to bolt or clamp on everything to make sure it all fits. Then decide about the welding. I ended up welding mine in with a bead, then plug (rosette) welded them also to the panel that attached to it.

I'd put it all together, then you'll know what you should do. IMO
Old May 2, 2011 | 01:06 PM
  #8  
toddpthayer's Avatar
toddpthayer
 
Joined: Sep 2010
Posts: 26
From: CA
Default

Okay, I'll bite. What's a 'rose weld'

Thanks
Old May 2, 2011 | 01:34 PM
  #9  
2+2GT's Avatar
2+2GT
6th Gear Member
 
Joined: May 2009
Posts: 5,232
From: PA
Default

Well, it's more commonly called a "rosette weld". Basically, you pinch or drill a 1/4-3/8" hole in the top panel, but no hole in the bottom. Using a MIG welder, you weld through the hole to the lower panel, and fill the hole with weld, binding both panels together. Structurally identical to a spot weld, it can easily be ground and finished to have the same appearance as a spot weld, too.

Old May 2, 2011 | 03:50 PM
  #10  
toddpthayer's Avatar
toddpthayer
 
Joined: Sep 2010
Posts: 26
From: CA
Default

Great,

Tuning up what little I remember from welding classes 30 years ago.

Thanks,



All times are GMT -5. The time now is 03:39 PM.