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rficalora
Rob Ficalora
Willis, TX
(2764 posts)

Registered:
10/24/2007 02:46PM

Main British Car:
'76 MGB w/CB front, Sebring rear, early metal dash Ford 302

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header repair question
Posted by: rficalora
Date: March 30, 2009 10:12PM

A while back I nicked one of my headers with a cut-off wheel while trimming the holes in the inner fenders. The scar is about 1/16" to maybe 3/16" deep -- not through the tube. It's maybe 3/4" long. I want to fix it in a way the fix won't show through the ceramic coating -- am woried about whether a mig welded repair will expand/contract at a different rate than the surrounding metal making the ceramic coating stat to crack or flake off. I have also considered having it tig welded... toughts or recommendations on how to fix it?


Bill Young
Bill Young
Kansas City, MO
(1337 posts)

Registered:
10/23/2007 09:23AM

Main British Car:
'73 MG Midget V6 , '59 MGA I6 2.8 GM, 4.0 Jeep

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Re: header repair question
Posted by: Bill Young
Date: March 31, 2009 08:26AM

Rob, I think you're not going to be able to save the coating. Any scar which exposes base metal will begin to rust from the high temperatures and the rust will get under the coating and start to flake it off. As far as the repair, I'd TIG it. Mig usually leaves too much of a bead and needs grinding so that would disturb even more of the area. A good welder should be able to just fill the cut and make it almost smooth. As you probably realize, if you don't weld it you'll soon have a crack there, so either way the coating is toast eventually.


rficalora
Rob Ficalora
Willis, TX
(2764 posts)

Registered:
10/24/2007 02:46PM

Main British Car:
'76 MGB w/CB front, Sebring rear, early metal dash Ford 302

authors avatar
Re: header repair question
Posted by: rficalora
Date: March 31, 2009 08:44AM

Sorry, i wasn't clear Bill. The headers aren't coated yet. I'm looking to fix the spot before i get them coated.
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Bill Young
Bill Young
Kansas City, MO
(1337 posts)

Registered:
10/23/2007 09:23AM

Main British Car:
'73 MG Midget V6 , '59 MGA I6 2.8 GM, 4.0 Jeep

authors avatar
Re: header repair question
Posted by: Bill Young
Date: March 31, 2009 11:47AM

In that case the MIG should do fine as long as the wire alloy comes close to matching the header material which is usually mild steel I don't think you'd have any problems with expansion later. Just weld it up and smooth it out with a grinder or file and coat away. The ceramic coating will hide a lot of tiny scratches unlike paint as it's thicker. If you TIG weld that would be great, but no sense sending it out if you don't, just use your MIG. I used both MIG and gas welding on my headers and haven't seen any type of stress cracks from the heat cycling at any of the welds. You should be fine.


ex-tyke
Graham Creswick
Chatham, Ontario, Canada
(1165 posts)

Registered:
10/25/2007 11:17AM

Main British Car:
1976 MGB Ford 302

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Re: header repair question
Posted by: ex-tyke
Date: March 31, 2009 05:12PM

Rob,
Before I had my initial set of SBF headers ceramic coated , I took the time to file and emery all the weld joints (for aesthetic reasons). After 4 seasons of use, the header coating held up just fine over those reworked areas.


rficalora
Rob Ficalora
Willis, TX
(2764 posts)

Registered:
10/24/2007 02:46PM

Main British Car:
'76 MGB w/CB front, Sebring rear, early metal dash Ford 302

authors avatar
Re: header repair question
Posted by: rficalora
Date: March 31, 2009 10:05PM

Excellent; thanks guys. By the way, I'm planning to be in NC, but my car won't be done. It's really close -- if I could get 3-4 days to work on it it'd be ready to go to the painter. But weekends are the only opportunities & we have a cub scout camp out this weekend; easter the following with family coming in because #1 son is getting baptized; maybe 3rd wk of April I'll get some time in on it... anyway, looking forward to seeing everyone... and counting on a few of you to let me ride shotgun!


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