Welding in patch panels

[mopar4don]

Glad you didn't.. What you've shown there is a good testament to what can be done with a bit of determination and minimal tools.. And to think 15 to 20 years ago someone would have tapped in the rust holes, smeared the bondo on the panel with the drips through the holes to "anchor" the filler, and painted. Congrats on showing there is a better way, easily obtainable..

lol, Yes I had those bondo anchor's on my car!
Next I have to weld it up. So stay tuned, I'm sure I will have questions.

 

[larry4406]

Nice job!

I've heard of bondo worms before but never anchors. I guess visual and functional descriptions, respectively.

 

[mopar4don]

update:

so I started welding her in
Robert, I took your advise and set the machine to the next setting higher, and it seemed to work most of the time. good penetration and the welds seem to lay pretty flat

with an occasional blow threw that I would grind out and fill with a piece of metal from the Roper and Whitney punch

a little tape on the back side to hold the plug, then weld from the front.
(hmm were have I seen this before??) (Robert it worked flawlessly)

fast forward and here is that patch all welded up

and welds ground down

 

[MP&C]

I think you are done with the class.. Nice work Don!

 

[mopar4don]

Thanks Robert for all of the help!

 

[MP&C]

You update your progress on the mopar/charger forum and they all will be sending you fenders to work on!

 

[mopar4don]

Yeah..... NO
I'd like to finish my project sometime before I'm old! OH WAIT, too late I am already old!

 

[toms73novass]

Quick question Robert, I have to fix this area but there is no access behind the panel, except the very edges, and the whole panel is welded in place.

My thought was to cut out the area indicated in red and do my best to weld but not be able to panish most of the back side.

Would this be the best cut for this situation or would you recommend a different cut?

Thanks
Tom

 

[MP&C]

Where is this on the car? Got a non-close up picture?

 

[toms73novass]

Front Fender, rear section, just before door.

 

[MP&C]

Looking at this picture, the red line represents the section view of the lower fender. This is a rather high crown area, that any shrinking is going to move the weld area inward, where it forms a valley, represented by the yellow line. This is the unfortunate issue with your proposed cut seam in the post above, any vertical seams will have this result absent any planishing.

My suggestion is to use a horizontal seam as shown by the green line, and form the patch down to the spot welded flange so it can be replaced per OEM. Vertical seam at the rocker as shown, and seamed inside the door jamb for the upper right radius. This should also give sufficient room to inspect inside the rocker for addition pitting / rust issues and room to repair any rust damage to internal structures behind the rust you see exposed. There's always more than meets the eye..


I would also recommend using TIG to tack in place and use a non-stop weld seam, as much as practical, to minimize any shrinking and distortion effects. Absolutely tight joint will be needed for this.

 

[toms73novass]

Robert thanks for you wisdom!

When you say non-stop weld seam are you saying doing in one continuous Tig weld, not the dot method with the mig?

 

[MP&C]

Yes. As much as possible make one continuous pass. Starts and stops add distortion.

 

[toms73novass]

ok thanks!

 

[MP&C]

As this thread also discusses stepped flange (overlap) welding, this is a good place for this video link..


Ok, you guys have heard me talk incessantly about the downside of using flanged seams in sheet metal repair, discussing the ghost lines that can and will occur with these type of repairs. Today I got a short video to show the effect. This car was neat as a pin, with extensive rust repair performed, in basically the same locations as the 55 we're working on. The only flaw I could find in the paint was a line in the finish where the rear tailgate's lower rust repair patch was seamed. I asked the owner if he had used flanged seams in the repair, and he said yes. He did offer for me to take pictures that others may learn from it..

**** welds people!!!!!!!

.

 

[E12-535iTurbo]

Thanks Robert for teaching us!

 

[JABgj]

I'm hoping I can jump in with a question. I am working on refurbishing a hood for my Ranchero and on the underside it has some rust issues. It looks like some of the spot welds that secure the skin to the support structure are a rusting/bubbling thru the skin.
Can I clean up the 2 parts, possibly using a spot weld cutter on the skin and plug weld these up and grind and finish in a similar manner to what has been shown in this thread? Thanks.

 

[MP&C]

Hard to see what you're showing there, can you show something not so close so we can figure out where you are on the hood?

But yes, many high end restorations will split parts like the hood away from the structure so that you can insure there are no hidden issues, and all parts can be properly painted prior to assembly. In many cases the factory had bare metal anywhere that paint couldn't be sprayed AFTER assembly had already taken place.

 

[JABgj]

Hard to see what you're showing there, can you show something not so close so we can figure out where you are on the hood?

But yes, many high end restorations will split parts like the hood away from the structure so that you can insure there are no hidden issues, and all parts can be properly painted prior to assembly. In many cases the factory had bare metal anywhere that paint couldn't be sprayed AFTER assembly had already taken place.

Here are a couple more pics. I am quite the bodywork noob so taking the skin off the support structure is at the very least scary.

[/url]DSCN1288cropmarked by jabphotos2009, on Flickr[/IMG]

DSCN1299 by jabphotos2009, on Flickr

Thanks for having a look.

Jeff

 

[MP&C]

The more I look at this, the less it looks like a spot weld.

The hood skin should be spot welded around the outer perimeter where the flange is folded under to the inner structure and around that hood scoop opening, but almost NEVER do you see spot welds farther in from there. Some daubs of semi-flexible adhesive may be used between the two, but that should be it. Not sure what is going on here...


Is that a 70/71? I would think you could still find a good one in a salvage yard in AZ or similar dry areas, which may save you the headache of separating your hood..

 

[JABgj]

Robert,
Yes, it's a '70 and pristine GT hoods are pretty hard to find. I assumed it was a spot weld but what you have pointed out makes sense. I am going have to see what I can come up with to make what I have work. I am willing to take a chance and cut a round hole around the rust hole and weld in a mini-patch. If this hood is borderline, I can't make it much worse. (Fingers crossed)
Thanks for looking,

Jeff

 

[89GLH]

I love these threads because Robert comes in on his white horse and shows us how it's done. I've used his advice several times and it's never been wrong. Cheers.

 

[MP&C]

Jeff, are you using MIG, TIG, ???

I love these threads because Robert comes in on his white horse and shows us how it's done. I've used his advice several times and it's never been wrong. Cheers.

I think that dang horse has thrown me a couple of times..

 

[JABgj]

MIG, no gas.

JB

 

[MP&C]

Jeff, I may have a line on a hood in Riverside. Sent you a PM.

 

[MP&C]

Jeff, here's the pictures. Per Brad, "I took pics of everything i could see wrong with it the hood is straight small hole right front and small bubbles on top"



I don't think it's perfect but I'd say it's worth looking at. Also shows they're still out there. I'll pm you his contact info ..

 

[Slednut]

Sorry if this has been asked, how well you grind your welds that end up under the carpet. Is there a good reason to go all the way smooth, I'm thinking the welds will be stronger if I don't grind them all the way down.

 

[MP&C]

What do your welds look like on the back side?

 

[Slednut]

Most had good penetration, a few places the panel fit was really good, and that is where the penetration isn’t good.

 

[MP&C]

That sounds like you're saying you had good penetration where you had a gap. That's not weld penetration, that's filling a gap. Set your heat for a full penetration weld on a zero gap joint. If it tends to blow holes, increase the wire feed speed.


Back to your original question, you shouldn't have to rely on excessive weld for strength if the weld is done correctly. If you don't want to grind because it's too much like work, that's one thing. If the welds do not have sufficient weld penetration, fix the issue at the weld stage. A crack on the back side or cold joint from insufficient weld heat is a weld that is subject to failure. Some of those welds do appear to be sitting on top with minimal penetration. More heat!

 

[Slednut]

Thanks so much, my welders chart read 4.5 and I used 5 but I did leave the wire speed at what the chart said, I’ll grind it down and redo some of the areas. I'll turn up the heat and wire speed.

 

[428street]

Hoping I can jump in here with a question. I'm a complete novice and it has taken me years to get going on some sheet metal work and by that I mean, taking spot welds off, grinding, buying some basic tools, etc. I have a couple of Scout 800's I am restoring and these trucks are known to have rust and rot issues. I have taken off two end caps and both need work. One needs some patch work and a little hammer and dolly work, another needs to hole filled from previous repairs using bondo. All panels are stripped to bare metal. I've walked several video's on hammer and dolly. dolly on and dolly off. Dolly off to get the basic shape, dolly on to fine tune. Use the best dolly to match the shape you want the metal to become or go back to. So I've seen the h/d explained a couple ways. First one is (on a small dent), the dolly goes on the top of the concave crown and you push the dolly toward the direction you want the metal to go back to at the same time hammering around the crown of the dent. The other way I have read which I don't think is right is to hammer the concave crown out (just the opposite of what I said before)...any help with this?

I've attached some pics of the first end cap and the tools I have purchased over some time.

 

[MP&C]

....the dolly goes on the top of the concave crown and you push the dolly toward the direction you want the metal to go back to at the same time hammering around the crown of the dent. The other way I have read which I don't think is right is to hammer the concave crown out (just the opposite of what I said before)...any help with this?

I'm confused on your post..

1. Concave crown would be a low, or bowl. Putting a dolly on top of a concave crown would have it on the outside with you hammering from the backside.

2. Hammering a concave crown out would be to hammer from the backside.


So it sounds like you are describing the same process twice.


Are you trying to turn a concave crown into an outward crown? If so, providing you have adequate room for swinging a hammer from either side, what difference does it make? Sometimes you get better results with the hammer providing the persuasion from the backside of the dent. Skinning cat syndrome.

 

[428street]

Sometimes I confuse myself sir!

To answer your question I am trying to make this particular dent on this end cap flat or in laypersons terms, take the dent out.

Let me restate and try to use the correct terminology. Let's take for now pic two which is a close up pic of the small 1.5" dent in one of these end caps. I see it is in metal shaping terms called a low which makes sense. Something hit that area from the outside causing the metal to bend in towards the panel. My question is do I place the dolly on the back of the panel and push inward (toward the front/face) of the panel while lightly tapping around the edges on the front/face of the panel? My thought is first in, last out. The low should be the area that was hit first I think I read (and that is dangerous) that you should never try to fix the area that was hit first because you might over stretch. Thank you for your patience on this. It's take some time to get through my brain but when I get it I'm good.

 

[MP&C]

http://www.hnsa.org/wp-content/uploads/2014/07/metal-body-repair.pdf

 

[AJ.]

I am doing a rebuild of a Landcruiser Ute, whilst stripping the paint I found some rust that had previously been "repaired" so this was my first real attempt at a patch panel.



That is a very good example of exactly how to NOT fix a rust patch

Step one make a tape template.



Then transfer that to a suitable piece of body metal, in this case a panel I got from the local crash shop



Then start trimming the guard to expose the true quality of the previous repair I will have a bit of work to do on the inner section as well.



Then make the patch panel and see how it fits. Hopefully my repair will be an improvement on the previous effort.



Obviously the frame needed some attention before I weld on the outer patch panel.
When I removed the bog there was a big rust hole, you can see in the first picture where I drilled that out and attempted some spot weld repairs which it was pretty obvious was not going to work. So time to make a patch panel for the inner frame and weld it in. the start of the panel (cut to shape) is in the first picture.



Time to start shaping, a small V shaped gutter was the first spot to get the hammer treatment.



Add some curves, a return and a return folded edge and its starting to look something like the piece to be cut out.



Then cut the rusty section out and do the final trim and fit.



Then weld it in and clean up the welds. I have a bit more cleaning up to do on the outer edge. The welds in the top recess I will leave as they are. It’s quite difficult to get in and grind them and they will never be seen and won’t interfere with the outer panel, so they will stay as is.



After I finish the cleaning up I will sand blast that section and give it a few coats of primer before welding on the outer patch.
Onto the outer patch.











A view of the back side of the repair, that just needs some tidying up before priming and painting remembering that area can not be seen once assembled.



what I started out with.



And the end result of the repair.



A skim of body filler over the repair area and it should be as good as new

Cheers Andrew

 

[MP&C]

Andrew, quite an improvement!

 

[AJ.]

Andrew, quite an improvement!

Thanks, I have learned most of what I did in that repair from your threads

Cheers Andrew

 

[AJ.]

So after the success of the last rust repair I thought I would tackle the only other little bit of rust I have found (other than surface rust) in the left sill panel. Just a couple of small spots so should be a quick and easy fix



After a bit of trimming it's no longer looking like a quick or easy fix Great design putting a double skinned panel as low in the cab as possible NOT!



First step was to make a profile template for when its time to make the outer patch panel.



Then cut out some more panel to expose the nastiness. There was around a 2mm gap between inner and outer panels, just perfect for collecting dust and water.



Outer panel trimmed enough to remove all the dirt and see how much inner panel needed removing.





I have 2 main objectives here, firstly repair the rust, but secondly stop it from happening again. In order to prevent this re-occurring I plan to reshape the inner panel to give a gap closer to 10mm between panels to stop dirt accumulating. Part 2 of the plan is to improve drainage from the inner panel so dirt will either fall out or can be washed out effectively.
First step to improve drainage was to add 3 drain flutes along the bottom of the sill panel, I used the tooling I posted a few pages back that I made for the beads in my toolbox, it was pretty easy to get the drains shaped.





Now to see how I go shaping the repair panels.


Cheers Andrew

 

[AJ.]

The inner patch panel all knocked into shape.



I put a couple of 12mm holes in the lower section of that panel to allow for drainage as well. Then time to weld it in. This section will not be visible so I didn't need to finish it off perfectly.



Now for the outer panel.

Cheers Andrew