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Advice/inspiration on dealing with rust

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Yeoman

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Starting to tackle the rust problems on my '71 Midget. I'm completely new to bodywork. I've bought and read Porter's and Lindsay's restoration guides, as well as Haynes' body repair manual. And a decent gas MIG. I've done a couple of patches with singularly ugly but mechanically sound results. I know I need more practice, and then more practice.

I want to replace the spring hanger box on the front of the left side leaf spring. I've got the inside bulkhead repair panel, and the floor repair panel. And I'm scared to death.

I can't take the time for a welding class at a local school. Are there any more books on the subject that might make me feel like I'm not out of my depth?

About 10" of snow to shovel, and I'm off work 'til after the new year. The first path I'll shovel will be to the garage so I can look at the rust and stroke my chin and drink coffee. But not actually disturb any metal.

What's the best way to drill out the spot welds?

Thanks.
 
I'll try the 5/16" bit tonight. I used the 1/8" pilot on a couple of the welds already.

What's the preferred method for cutting out the old stuff? I've got a cheap 4 1/2" grinder, an antique jig saw, and a sawzall.

What joint do people use when installing the new panels? Should I get a "joddler", or is butt welding the way to go?
 
Three words

PRACTICE PRACTICE PRACTICE

You cannot learn the touch from a book the mechanics of welding yes but it takes a touch that can only be learned by the three words
 
You use what it takes to cut away old metal, sometimes a diegrinder with a thin disc, sometimes an airchisel, sometimes a sawsall, sometimes a grinder!! Depends on what you are joining as to what method you use. It seams that you are removing and replacing full panels in some places, so you use visegrips to hold them in place and then fill the holes that you drilled out and grind them off!! It's a lot of work to do a good job, but if you want to you can!! This helps too!!
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Yeoman;
Eastwood sells a bit specifically for drilling out spotwelds. I have not used it myself, but if I restore another car that needs panel replacement, I will try it.
As stated above, practice welding on scrap sheetmetal.Use a series of short stitch welds to do patches, alternating positions to keep heat/warpage to a minimum.take your time. Use a wet sponge to dab area to cool off. Do some plug welds thru holes. Cummins and Harbor Freight have inexpensive punch sets for punching up to 1/4" holes, these work great for plug welds to somewhat reproduce spot welds.
I try to fit any patches or panels as buttwelds.Carefully grind welds flush using a coarse sanding disk, these remove metal quicker and put less heat into the metal than a composite grinding wheel. Again, sand a little, cool with sponge. Wear safety glasses, and or a face shield, gloves and particle mask, as well as full covering when welding to prevent burns.(from uv rays as well as sparks) You will be surprised at how fast you end up with red lines on your arms and neck from uv rays from the welding arc.
 
now I have an idea how to get a tan in mid winter without going to the fake and bake
 
Yup, learning to weld is a challenge!! It is all about cleanliness, and setting your gas, heat and speed!! The only way to do it is to try different settings, or take a course!! I was lucky, 'cuz I have a good friend who helped me get everything set right and then it was just practice!! If I was you, I would just keep on trying and you should get it!! Remember, don't ever weld too much at one time!! Practice on some old metal the same thickness as you will be welding!!
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As far as spot welds, go to your local parts store that sells auto body supplies, and they will set you up!! All I use is a double ended 1/8" bit to drill a pilot hole and then a 5/16" bit to drill them out! Somebody on the other board told me that there was something waaaaay better, but that method worked just fine for at least a thousand spots for me!!
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Pete - much appreciate your post, sounds like I'm on the right track.

Last night I tried the 1/8" pilot and 5/16" drill and separated the inner bulkhead from one of the three triangular reinforcers. Did the job. Very satisying to hear it pop apart when pried a bit. But I wonder if I should be using a lower angle 5/16" drill. The one I have seems to take a fair amount of metal off of the inner part, and I'm hoping to save one of the three inner reinforcers. I've thought about the Eastwood bit and I'm hoping it will preserve more of the inner part. If I can't get something at a local auto parts place, I'll order the bit today.

My experience was that a 40 grit sanding wheel did a nicer (and quicker) smoothing job on my bulbous welds than the grinder, but I just didn't believe it. Now I do.
 
I'm really into it now.

I ordered the Eastwood bit and some cold galvanizing spray. I've left some spot welds to do, but I think they're the easy part. What's the trick for separating seam welds? I've tried thinning the metal with a 36 grit sander on my grinder, as well as a 1/4" wide grinder, and it sure seems to be a slow process.

It's amazing how easy it is to cut rotten metal. It's also amazing how difficult it is to weld metal with any rot at all.

By the way, what the heck is a bolster chisel? I've seen references to it in books and magazines, and I wonder if it's what I need on these seam welds.
 
It seems to me that the outer flanges of the floor pan aren't spot welded, but are welded continuously. Specifically, it's where the floor pan meets the inner sill and the outer heelboard. Maybe as I keep grinding I'll see that they really are spot welded and were just too rusty for me to see the depressions.

[ 12-28-2002: Message edited by: Yeoman ]</p>
 
Ahhhh!! Seam weld
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Yes they are, and that is how I replaced mine!! Some of the guys say that you only have to weld an inch at a go, mis an inch and so on and use seam sealer!! As for me, I perfer the solid weld, but the other probaly works fine!! Just keep struggling with it, and you get there
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I did the same job, and then some on my 67 Sprite.I also replaced the 1/4 panels,inner fenders, rear valance and floor pans. I had no formal training on the mig, only what my friend at a porshe restoration shop showed me. even with that it all takes practice on your own machine/settings ect. and yes it is a scary thing to cut off the old metal and welding new in its place. however you will always have the satisfaction of knowing you did it yourself. After painting, is the most fun "assembly" The most "enjoyment" The first drive....It will keep you grinin ear to ear! Good Luck!!!

JUST B CRUSIN
67 SPRITE
74 MGB
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