Jump to content

Recommended Posts

Hi Guys, Well I have purchased a Hobby Mig Welder which has the option to use Gas.  I have purchased a disposable bottle of Argon /CO2 Shielding gas mix.

I'm running 0.8 wire.  I have been  playing around with wire speed and heat settings on some sheet metal but I think I'm now at a good place to actually start work on the car.  Ist Job is to weld in a rectangular patch panel under the rear seat area.  I plan to attempt to butt weld in the panel and then grind down the welds to "almost" smooth.

My question is about seam sealer.  Now once I have finished the welding, do you use the seam sealer direct to the bear metal or do you prime the new metal first, then use the seam sealer?  Also, What paint are you using to cover the newly welded area.  All my welding will be related to the floor pan areas so would like to know the preferred choice of chip proof paints.

Thanks   

 

Edited by 92GTS-R
Link to post
Share on other sites
  • Replies 30
  • Created
  • Last Reply

Top Posters In This Topic

Top Posters In This Topic

Popular Posts

I would recommend getting the old metal much cleaner. I use a 1/4' air angle grinder with 3M  2" roloc grinding wheels in 36 grit for grinding welds down or 50 grit for cleaning old metal.  Your old m

To answer your question about phosphate, here is what I use, hopefully there is something comparable over there. It can be used on rusted or bare metal. https://www.amazon.com/Krud-Kutter-Remover

If the new welded in section is pure and blank steel, you can try to get Fertan. In general it is a rust converter, but if used on blank steel it covers the surface from getting rusty. https://ww

Posted Images

Even     with your welds  being new you need to clean them with wire brush on drill. Then phosphate the weld & bare metal and then epoxy prime. Ford put the sealer on bare metal but when you do that once the sealer cracks you get rust started on the bare metal. Got to go to Dr. can get you number for the sealer when i get back. If you are inside the car like inside a door or floor i prefer to brush primer on to get into the corners and cracks. If it runs to the outside wipe it off.

When a man is in the woods and talks and no women are there is he still wrong??:P

David

Link to post
Share on other sites

I don't know what you mean by "Phosphate the weld"  Could you explain, thanks, also (being in the UK) I might not be able to get the exact same paint, so will have to find a brand equivalent :)    

Link to post
Share on other sites

@92GTS-R " I have been  playing around with wire speed and heat settings on some sheet metal but I think I'm now at a good place to actually start work on the car. "

Not doubting your fast learning skills and glad to see you go for it! Before you start weld there, know that it's not new clean metal (yes you know that :) ) and as the floor is set under tension and part of the car strength. The welds need to be strong. not 1/2 strong. Sound obvious but practice showed me that it's not that easy even after hours of practice to be constant.

So I'd really make sure you are indeed ready for that one. Especially using new and old metal to make sure you obtain welds with good penetration. Which means using the right power and wire feed speed and then test/destroy to see how good they were. Also try to reproduce the angle in the car you will need to weld. Welding on vertical surface on your knees is much more difficult than welding 2 pieces on a flat surface from above... You'd be amazed how easy it is to make holes vs close some when you weld new metal to old one. Or the reverse, make nice looking welds that will popup the moment the metal cools off. So If your car needs repairs on the rear lower quarter or doors bottom, I'd start with that instead as its not "that" structural.

Note that I'm nowhere near a good welder myself, and do not want to play the "know better" guy here! See it as a constructive remark based on own experience!
Just trying to tell you that it is structural welds you need there, you are not allowed to  "fu..." them! :D

Good luck and let us know how that goes! Did you find a place to work btw?
 

73 modified Grande 351C. (Finally back on the road woohoo!) 

71 429CJ. ( In progress )

Link to post
Share on other sites
1 hour ago, Fabrice said:

@92GTS-R " I have been  playing around with wire speed and heat settings on some sheet metal but I think I'm now at a good place to actually start work on the car. "

Best settings seems to be heat setting 1 and 0.8 wire feed just under 3. using the Argon /Co2 mix.

Good luck and let us know how that goes! Did you find a place to work btw?
No, I'm working on my front drive :(

 

Link to post
Share on other sites

Welds are decent for a beginner, I've seen MUCH worse. Keep at it and you'll be a pro in short order. Like David said, the key is cleanliness. Phosphating the weld is done using a phosphoric acid based solution to clean the metal and leave a zinc phosphate layer behind. I use Rust Bullet's Metal Blast. 

I'd practice your butt welds before committing to the floor patch. I'd also consider picking up a spool of .025" /.6mm wire and tips. You might find it much easier to use on the gage sheetmetal you'll encounter than the .031/.8mm wire. 

As far as paint, I currently use Rust Bullet on any rusty metal repairs. POR15 is not the same since the company was bought out. 

https://rustbulletuk.com/en/

 

 

Link to post
Share on other sites

Eeeewwwwwww!!! You made worms!!! :D

Try again connecting 2 plates of old and new metal and have the sheets stand vertically as you will need on the contours of the seats in the car. Worms hate gravity ;)

edit: you posted the pict while I was typing. Do remove ALL the rust before weld both side need be shiny clean. DO NOT USE a grinder as you will reduce the thickness of the old metal even more.

"No, I'm working on my front drive :("
Oooh man, I'll think about you when I'll watch the weather on TV!
I did my brakes this weekend and it was a cold experience! Good you will have heat :D

Edited by Fabrice

73 modified Grande 351C. (Finally back on the road woohoo!) 

71 429CJ. ( In progress )

Link to post
Share on other sites

To answer your question about phosphate, here is what I use, hopefully there is something comparable over there. It can be used on rusted or bare metal.

https://www.amazon.com/Krud-Kutter-Remover-Inhibitor32-Bottle/dp/B0044UP9XU/ref=sr_1_1?crid=TW6PLY68XXKN&dchild=1&keywords=must+for+rust&qid=1606245996&sprefix=Must+fo%2Caps%2C458&sr=8-1

It's good to use after you sand off a section of paint, so you don't have to immediately prime it to prevent flash rust.

  • Like 1

 

 

“If you can't explain it simply, you don't understand it well enough.”

--Albert Einstein

 

Link to post
Share on other sites

If the new welded in section is pure and blank steel, you can try to get Fertan. In general it is a rust converter, but if used on blank steel it covers the surface from getting rusty.

https://www.fertan.co.uk/

It's easy to use and a 0.25 litre bottle it totally enough for a long time. but it is necessary to follow the instructions.

Cheers Frank

Edited by Vicus
typing error
  • Like 1

1972 Mach 1, 351C-2V, wimbledon white, blue all vinyl luxury

born in Dearborn, grown in the district of San José, spent a lifetime in California, moved to Germany in 2010

Mustang_Mach1_wallpaper_300_150.jpg proud member of clublogozusammen.JPG.59fb4a10d15cfff9ec756235059135b8.JPG

Link to post
Share on other sites

This is a pic of a piece of the old rusted floor pan and I tried (for fun) to see if I cold join on a piece of new metal.   It Worked!  and the weld is strong!

I Started off with some spot welds then joined them up.

Also tried a couple of butt welds 

 

IMG_20201028_135510.jpg

IMG_20201028_135605.jpg

Link to post
Share on other sites

You're a natural m8!

It's been said a few times but one more time:
Make sure the metal is shiny clean before welding on both sides of both sheets, welds on rust or dirt will fail soon or later!

Edited by Fabrice

73 modified Grande 351C. (Finally back on the road woohoo!) 

71 429CJ. ( In progress )

Link to post
Share on other sites

looks good!

20160504_113653.thumb.jpg.b0ca31b0f930cdfd6b122dbdb01279cd.jpg

I had to do it at the same place but much smaller.

20160504_142419.thumb.jpg.3119714e762d8c91a1b464c1135015bc.jpg

Here you see the dark black parts, covered with the rust converter, and the blank part in the middle, where the rust converter Fertan didn't turn black but brown.

20160505_133811.thumb.jpg.32852434d3f7ee904a8422c098d3dac4.jpg

And that's how it looks like after being painted.

  • Like 1

1972 Mach 1, 351C-2V, wimbledon white, blue all vinyl luxury

born in Dearborn, grown in the district of San José, spent a lifetime in California, moved to Germany in 2010

Mustang_Mach1_wallpaper_300_150.jpg proud member of clublogozusammen.JPG.59fb4a10d15cfff9ec756235059135b8.JPG

Link to post
Share on other sites

I would recommend getting the old metal much cleaner. I use a 1/4' air angle grinder with 3M  2" roloc grinding wheels in 36 grit for grinding welds down or 50 grit for cleaning old metal.  Your old metal has to be shiny new looking or you will contaminate the weld.  Also you want to ditch the .030 wire and get some .023.  The .030 is too big for sheetmetal work. The heat it takes to properly melt the wire usually will distort or burn through old thin sheet metal. Since it looks like you are running the smaller 140 machine it will definitely benefit you to run the smaller wire.  Do not try to run any beads on sheetmetal. Just a spot weld, then move on, spot weld, move on....... don't get the panels too hot.  On the floor its not as important but on a quarter panel or something like that you dont want to warp the panel.  I even carry a damp rag with me to cool my welds as I go. 

As far as seam sealer goes, you can put it on bare metal if the brand your using says you can. Some say it must be installed over epoxy primer.  I have done it both ways. I usually use Fusor seam sealers. 

 

Heres a couple pics of the quarter panel Im patching up on a subaru outback.  Make sure you jump around with your spot welds and dont try to run a bead no matter how tempting it is. 

 

 

516A1EDB-064F-4E67-8726-F57F901BBC8E.jpeg

3DA65B4C-AA91-4C38-BE00-FF13BCDAF12D.jpeg

8EA021A3-352A-4796-8A8A-752BB329D9CA.jpeg

DA4ABC85-3030-41D9-8A63-0D26F3462B42.jpeg

E7EA2781-DEAF-4352-B58E-46BA1937C205.jpeg

232B913C-E59A-4DFA-9F5D-2B874F8E6E46.jpeg

EB2C1FEA-A5C8-4742-BD9E-FF2E4020776A.jpeg

CFE04353-516B-40A8-8052-D5DD26A7D4F4.jpeg

D8644A3B-E420-4848-886A-C18465EDF893.jpeg

Edited by turtle5353
  • Like 2

Kevin
1971 Mach 1

408C Stroker - C4 w/3,000 stall - 8.8" Rear w/3.73's - Disc brakes all way around.

 

 

Link to post
Share on other sites

Also another quick tip, when you strike an arc, start it on the new piece of metal and then whip it over to the the old metal.  The new metal is usually thicker and can take the initial arc of the wire better. 

  • Like 1

Kevin
1971 Mach 1

408C Stroker - C4 w/3,000 stall - 8.8" Rear w/3.73's - Disc brakes all way around.

 

 

Link to post
Share on other sites

I'd second that .030" wire is a little big.  Find some .023"

I have found that compressed air is great to cool the weld.  It minimizes heat distortion and helps keep things clean.  I prefer it over water or a damp rag.

You may also consider finding some copper bar to use as a backer for your butt welds.

Successfully welding gas shielded outdoors is dependent on wind.  You may be able to crank your shielding gas regulator up to help out a bit.  If it isn't still outside I wouldn't weld.

After welding try to remove the excess weld material as skillfully as you can without getting into the base metal.  Consider knocking down your tacks as you go with whatever you are using.  Personally I have found a 36 grit 3M Cubitron 2 disk to cut like butter and produce very little heat.  

Last bit of advice is to trim the ball off the end of the wire between every tack.  Welding sheetmetal with a mig welder usually involves the welder to be set down in the dirt.  With so little voltage to work with starting with fresh cut wire will ensure repeatable arc starts / heat.

Link to post
Share on other sites

On my comment about phosphate. When cars are built at the factory part of the wash process is to on into Iron phosphate. It etches the surface and makes the paint stick better. You can do the same at home with hand spray on and rub with scotch brite or steel wool. What I am using right I got from POR but your paint supplier should know what you need. Follow their instructions makes the paint adhere much better. Here is a link to information on the material. Brand is not so important. When they dip strip a car they iron phosphate it and it can sit months and not rust. I have stripped panels in garage that have been there for years with no paint and no rust. Best to do the process and then epoxy prime. https://www.bonderite.com/en/technologies/pretreatment/iron-phosphating.html

 

When a man is in the woods and talks and no women are there is he still wrong??:P

David

Link to post
Share on other sites

Update, well its taken me 3days to try and weld in a patch and its still not over :(  Its sort of a case of 1 step forward and2 steps back :(   

I tried to butt weld in the patch panel, it started off ok but grinding back the welds had been a tricky business, then when I shine a light under the patch panel I can see pin holes of light in various areas so have to try to add more weld, then grind back etc etc.

I did change the wire to the thinner wire.  Its getting there but I'm still not happy.   I will post up some pics.

Link to post
Share on other sites

It's not an easy job on itself and welding old metal with corrosion isn't helping. 

Often dismissed as a piece of cake, grinding right isn't that easy, especially when the sheets are not flush. Its very easy to weaken the metal and end up making a hole when you try to fix the tiny spot where the light shinned from!  Personnaly I usually grind only once the entire circle of welds is done and then do a 2 passes grinding. First using a thick disc hold as much as possible 45 degrees on top of the beads ( minimises to touch the surrounding metal and heat is little) and when its down to .5 mm, I use abrassive 80 disk after to finish and do not push as metal would turn blue in no time.

To minimise your 'light' issue, once all is in place and you fill the blancs between welds, start 2/3 on the previous point and pull or push the bath  3 to 5 mm away, this tend to remelt the first one and also give you a good start for heat without loading too much the sheets. Wire speed is important and doing so you should hear a high frequency buzzz. If not and bead looks ok but thick, reduce speed a tad. I know this took me a while and can't really describe in words but it's the sound the welder makes that you should listen. It really talks to you :)

Hope you'll be done soon, its really no weather to be outside atm!

 

73 modified Grande 351C. (Finally back on the road woohoo!) 

71 429CJ. ( In progress )

Link to post
Share on other sites

I’d suggest getting some scrap sheetmetal and refining your technique.  I had to practice for hours and hours over a few days to get to the point where I felt comfortable welding on my car.

 

If your are seeing pinholes they could be from you not overlapping your welds enough. Weld porosity from welding where the air isn’t still, and having your shielding gas blown away may be another pinhole issue.  Last thing is weld porosity from dirty metal / paint.

 

Overlapping welds is a pain.  The correct amount of heat for thin sheetmetal isn’t enough to penetrate a previous big old cool bead.  This is why I grind my welds between passes.  I don’t grind them all the way down to the base metal, I just knock most of the bead off so that when I make my next round of tack welds the material Is a more consistent thickness.  This makes it easier to penetrate into the cool spot welds and not nuke a hole in the sheetmetal.

You’ll get it- just keep practicing.   Also it is normal to chase some pinholes- you are bound to make a few.  

Link to post
Share on other sites

Well I've come in this evening after yet another day on the same piece ,it just got worse and worse and to say I'm upset is a massive understatement Yesterday I managed to slice into my finger with the angle grinder along the side of my nail and probably about 1/8th deep (that hurt).   

Remember I really did not want to do this Job in the first place but after being messed around for several months by so called welders i found via google, I had no choice due to a small retirement pension and could not shed out thousands of pounds to top American car restoration companies.

Sorry for the rant, just feeling down at the moment.

IMG_20201126_140634.jpg

IMG_20201126_164949.jpg

IMG_20201126_165004.jpg

IMG_20201126_165016.jpg

IMG_20201127_115916.jpg

IMG_20201127_115928.jpg

IMG_20201129_111309.jpg

IMG_20201129_111315.jpg

IMG-20201129-WA0013.jpeg

Edited by 92GTS-R
Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

  • Recently Browsing   0 members

    No registered users viewing this page.


×
×
  • Create New...