TheSamba.com :: View topic - Framehead Repair-MIG or Stick?

Sat Jun 21, 2008 12:55 pm

I am in the process of removing cancer from the bottom of the framehead. The chassis is up un sawhorses, the old rusted pans have both been removed. Even the rear supports have rusted to the point that I have removed one, but I am delaying on the passender side because I think I better temporarily leave it for a dimensional reference. In hindsight, I wish that I had held back on the driver's side too, because thr front crossmember (Napoleon's hat) too is rotten alond the "wings" where it attaches to the pans and the frame head bottom piece. I have removed the framehead lower panel, and have media blasted the areas, which revealed the need to replace Napoleon's hat. I ordered the hat and the bottom plate ( for a 1965 by-the-way), and while the bottom plate fits fairly well ( small gaps at front contours), the hat just is totally bo-ogus! It does not fit the contour of the center spine, the master cylinder holes are too close to the center that the mounting hardware won't fit against the spine. But I digress. The question I have is this...

Do I need to weld the framehead bottom plate using the Bentley Bible specified stick welding, or is this doable with MIG? Same strength? And while I have your attention, I read elsewhere a guy wanted to cut and splice just the damaged sections of his Napoleon's Hat ( I did do a search)
but I do not think he (we) got an opinion on structural continuity and so forth. This new hat doe not look like it will seal with the front crossmember under the front of the body,(it has a rounded crossection, instead of flat right angles as the OG). Not to bash Suppliers/Mfgrs., but this is one of the only disappointments I have had. It looks only like a half hearted facimile of the original. Anyway, if any structural engineers are reading this can you chime in on welding choice? Thanks People :) :) :)

Sat Jun 21, 2008 1:03 pm

As long as you get good penetration, MIG is fine.

--louis

Sat Jun 21, 2008 1:21 pm

Thank Louis! Do you think I can make that with a Hobart 140 Handler? Do I just lay progressive beads over one another where the gaps occure, or is it better to put an additional strip of metal in the gap? Gap is about 1/8th to 3/16th of an inch. The edge of the bottom plate along the forward edge is rolled up (down) and has a couple changes in direction. This is where the fit is hit-or-miss.

Sat Jun 21, 2008 4:26 pm

I would try to fit the plate to the pan head so there is no gaps with a hammer. Pretty much all repo panels need some tweaking to fit right.

--louis

Sat Jun 21, 2008 7:03 pm

Gotcha-Thanks! :wink:

Tue Jun 24, 2008 10:22 am

for whats its worth. i have a hobart 140 too,and its my 1st body off build. im no welding source,but ive found once you get the heat and wire speed dialed in it'll be fine for this application. practice alot. like he said ,its about penatration. flux core is hotter,remember to change polarity if you change from gas to flux.

Tue Jun 24, 2008 12:10 pm

I did that very same repair (bottom place and napoleon hat) with a MIG. Did have to eek the replacement panel some to have it fit nicely but is is strong as a house now.

Tue Jun 24, 2008 4:39 pm

Many Thanks! I will probably attempt this next weekend, I want to get some new fuel line and replace the original, since it looks quite pitted, and once thats in I will close up the patient! :wink: :wink:

Tue Jun 24, 2008 4:43 pm

Whenever a "Welding method A versus method B" question comes up the answer is "whichever one you feel most competent doing".

Bentley was written a long time back, when stick was about the only way to go.

Wed Jun 25, 2008 7:41 pm

Did all mine with mig and it worked fine. Jeff

Wed Jun 25, 2008 10:46 pm

Mig is fine and your machine should be up to the task. Try and get the gaps as tight and even as possible. You can fill variances here are there. The 140 is great for the thin metal. Start with the recommended settings on the machine for the thickness you are welding.

Thu Jun 26, 2008 6:16 am

I appreciate all the input! That is what makes this site great and this forum work so well! The other issue as to whether or not it is advisable to cut ,splice, and weld the rusted portions of the Napoleon's Hat is still in need of answering. Should this be done? It is a structural member. The replacement piece is a real piece of scat, and would prefer to cut out the rusty ends. Would this work as long as the welds are truly strong with good penetration? :?:

Thu Jun 26, 2008 10:29 am

Always better to save the original. It is already lined up!

Thu Jun 26, 2008 12:52 pm

Major, I just checked out your gallery, wowsers! I will take your comment as a blessing! You have done some really nice work. Unless someone can give me a good reason not to cut and patch, then I will most likely add this to this weekend's agenda. I had entertained the idea of ordering another Napoleon's hat from another outfit, optimistically thinking that somehow I could get a more compatible fit, but I'm with you as far as keeping OG as far as possible.

Sat Jun 28, 2008 6:47 am

I've got a good Napoleon's hat section. I cut it off a frame head I used. PM me if you are interested or want some pics
Matt

Sat Jun 28, 2008 8:51 am

Matt, I pm'd you, but I am not certain if it "happened". So to cover all possibilities- yes I would like photos to lead to probable purchase. Thanks. And if you did not get my pm, please let me know here.