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MG MGA - 'A' pillar repairs

The RH A pillar has a dent from the past (unknown circumstances). Up till now I thought all I needed to do was make a vertical cut, straighten the metal locally and weld it back. Upon close inspection and comparison with the LHS, I find the pillar has bee pushed into the body at the top, about 3/8". and the pillar is rotated a few deg, as if the impact came from the side and front. I think it has affected the area of the screen supports although I don't recollect any difficulty when I removed the screen.
What is the best way to rectify this? I don't think I can just use brute force and pull on it with some contraption. I am thinking I need to cut first, pull into shape then re-weld. Any thought would be welcome. See pics on next posts.
Art
Art Pearse

The dent...

Art Pearse

Top view....

Art Pearse

Close up from rear....

Art Pearse

Art, Have you checked whether the A-post is perfectly vertical in both directions. If they are not then you will have problems with door alignment later.

If they are both vertical and the top hinge face hasn't been affected then you could leave it as it is.

On the other hand if you can't stand the thought of a big dent being there even though it is hidden then I would bite the bullet and remove the A-post. You should then have access to remove the dent without cutting and even twist it back into shape. It's only going to be an hour or so to remove the 20 or 30 spot welds.

From your second photo it looks as if the side panel at the top has parted company with the shroud flange. If that's the case I would definitely remove the post to correct it.....................Mike
m.j. moore

MJ, the dent itself doesn't bother me as it will be covered, but i will try and make it better. The pillar is still in the right place vertically where it is fixed to the body, but as you can see from the 2nd pic, it is rotated inwards a few degrees. Also from the 3rd pic, the body has got pushed in about 3/8" at the top, so it is no longer parallel to the B pillar. Is it really that easy to remove the spot welds? I have never done that before, except when trashing the bit being removed, when I use the grinder. Do the spot weld drills leave a hole in the body metal as well as the flange?
Art Pearse

Art..
Snap-on make a spot weld removing tool. It is a rotary saw about 3/8" diameter. It cuts the first layer of metal and then you grind the remaining lump off when you remove the first layer of panel.
You center punch the spot weld and the Snap-on tool has a centering point for locating itself.
I have used mine for almost 30 years and it still cuts okay.
Sandy
SANDY SANDERS

Art,
I would fix the dent first before I cut the A pillar loose. I usually weld a all thread stud to the affected area, pull the dent out with a nut on the all thread and a backing plate, cut the stud off and repeat the process until the dent is out. Then you can better determine what to do next. Hope this helps and have a good day!

John
John Progess

The first spot weld drill I bought was one of the fancy ones where you could vary the depth of cut and so stop after you have gone through the first layer. This was a poor tool and only did two or three before it gave up the ghost. See Ebay item no. 270666609141 for one similar. The next one I got was a simple cobalt steel spot weld drill 8 or 9mm diameter. This was much better but you have to judge carefully and stop when you have gone through the first layer; this is not as difficult as you might think because you are drilling at a very slow speed. If I have to get another one I'd probably go for 6mm diameter.

The position of the welds is usually fairly clear (you can see some of them in your picture 1) but if you lightly sand the area they will show up better. As Sandy mentions you have to centre punch the spot, as near to the weld centre as you can, to prevent the drill from moving position.

But the more I think about it the more I think you'll do a better job of straightening up the metal at the top of the side panel and front of the shroud with the post removed. Good luck..................Mike
m.j. moore

My advice is, you can save a lot of time and effort if you do some straightening before you drill out any spot welds. If you were to separate the pieces before straightening, it would be a lot of work to get them each straight independently, then properly mated up again.

If the body is not still on the frame, then put the body back on the frame, and secure it with at least two bolts in the body to frame brackets near bottom of the A-posts. This is to stabilize the sill area of the body to retain proper alignment to frame all during this repair process.

Start with a 4" x 4" wood beam (or equivalent) standing vertical inboard of the left side A-post. Bottom end should be nestled into the lower corner of the body aft of the body to frame anchor bracket. Top end should be nestled into the top corner of the body at the top bolt flange spot welded joint. Intermediate part of this beam should be snuggled up against the inboard side of the A-post, and also secure against the inboard side of the Pillar Top Extension (the part that curves as transition between vertical and near horizontal at top). In short, this beam should rest solid against everything on the inboard left side.

Place a similar beam on the right side in similar position (but not exactly same). This one should nest same way into the the body at lower end. Intermediate points on the way up should rest against or very near to the rear most edge of the A-post, especially near the top. Top end of this beam should be snuggle up against the Pillar Top Extension. In this position the beam will be some distance away from the fender top bolt flange, because this is where the body has been bent inward (see last photo above).

Then position a hydraulic body ram with one end mid way up the beam on left side, other end near top of beam on right side, and push. The idea is to use the entire left side of the body as a foundation, and push outward primarily at top of the right side A-post. If all goes well this should push the entire right side assembly directly back to its original position, including removing the twist in the post. You will have to push it slightly beyond the desired position, as it will spring back a bit when the force is removed. Sneak up on it a little at a time, push, relax, inspect. Then push a little farther, relax, inspect again, and repeat as necessary until the desired final resting position is achieved.

Assuming this works as planned, you may find the only thing left is to remove the dent on the outboard side of the post. If cut, straighten and weld is not satisfactory for this, then cut out only the affected (not straight) area of the post, butt weld in a replacement panel, and grind smooth. There is a good chance you will not have to break or re-weld a single spot weld.
Barney Gaylord

Barney, the body is off the frame right now, but your suggestion makes a lot of sense. I was wondering how to force it back and your suggestion makes a lot of sense. I will try this first.
Art Pearse

Another thing - the front and back clips are more or less independent at the moment. I fabricated the replacement inner sills and beams per your excellent instructions, and I think I will install them and connect the bottom of the LH A pillar first, then the body is a lot stronger to resist the jacking.
Art Pearse

Since you are doing the sills and the A post is knackered, would an "F-post" make more sense? I helped a person install one with the body still on the frame. Getting the door to line up was fairly easy.

Pictures:
http://www.motorcar-garage.com/gallery.asp?action=gallery&subaction=moreinfo&imid=1730

Hope this helps,
Bill
Bill Eastman

One clarification- the car in the picture is not the one I worked on. Not a big deal but I don't want to be seen as taking credit for another's work
Bill
Bill Eastman

I did think of this earlier Bill, but I have already made the sill beams and I don't fancy cutting out all the spot welds. I think Barney's method will work.
Art Pearse

Finally got it in to acceptable shape, using a screw jack approach - see pic. The rotation of the pillar I corrected with a sheet of 1/8" steel bolted to the hinges, reefing on it with an adjustable wrench. The wooden uprights are now parallel. They were 1-1/4" out over 2 ft.
I still have to check the windscreen fit.

Now for the dent....

Art Pearse

Yeah! Give that man a cigar. As said, don't n-weld anything, just push it back the way it came, and straighten everything at once. Get a little creative with the pusher setup. You may need to weld up a couple of split seams.
Barney Gaylord

another question re- door hinges. I was trying to do a separate posting, but the web site was not accepting it!
Anyhow, how are the door hinge screws retained, inside the door? I can't see any tapping plates listed in the catalogue.
Art Pearse

Just individual nuts on my car. Bob
B WALKER

No tapping plates on the inside of the door. Just plain old nuts and bolts.

Lmazoway

OK, thanks!
Art
Art Pearse

This thread was discussed between 10/12/2010 and 09/01/2011

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