Some progress to share:
Before continuing the previous post with the preparation of the repair piece for the outside-inner lower elbow area, I went on and actually cut out the bad metal, to really establish the repair piece I will need.
Here is the situation: The black sharpie line (circled in red) is where I have decided to cut and remove material.
Click to view attachmentThere are a few things to consider when removing this piece. First the floor is spot welded on the underside of it, then the two vertical walls of the firewall are flanged basically on either side of the oval port. Then, at the right end, I am actually cutting half way into where the engine mount is attached (embossment). I chose this location for a couple of reasons;
1- I wanted to see the engine mount metal behind it,
2- The engine mount will serve as overlapping layer.
Based on what I have seen in removing the engine mount on my donor part, there is actually a gap between the engine mount and the embossment in the Outside-inner long metal. The plan is to add a metal layer to do an overlap on that joint. Plus the engine mount itself is an overlap.
To preserve the various metal joining to the metal I am removing, I will be cutting and grinding it away, keeping the flanges intact and ready to receive the repair piece. Here is the beginning of the process on the left side:
Click to view attachmentAnd here is that metal removed:
Click to view attachmentCloser view where we can see the two firewall flanges, the lower half of the engine mount (right end), obviously the floor, and the flange of the e-brake cable guide in the cabin. All of these flanges are nice and solid and will be the welding surface as I plug weld the repair piece in (minimizing upside down welds).
Click to view attachmentNow, time to prepare the repair piece.
As show, in the last post, I need to dismantle the various sections of repair parts I have, assess their condition, and make a repair piece. The donor long I got was cut to the right of the jack post, basically behind the firewall. Therefore, the repair piece will have a vertical weld roughly in the middle.
Here is the rear half of the doubled layered repair piece:
Click to view attachmentSince I will need both inner and outer layers, I had to drill all the spot welds to separate them. This works well, but unfortunately leaves one of the two pieces look like swiss cheese.
We'll look into that later.
Click to view attachmentOverall, these two parts are pretty rust free and I am confident can be used as-is after getting de-rusted in citric acid.
Now looking at the front half donor parts, same process; drill the spot weld to separate the two layers.
Click to view attachment Unfortunately, these are not as good as the rear half's. Let's see what de-rusting will reveal...
Click to view attachmentAfter a couple of days soaking in citric acid, here is the result. The rear end of it is a little pitted but not major, The front end (with the hole for the safety belt) is compromised in the fold and will need to be addressed (circled in red).
Click to view attachmentMost of the rest of the donor long is heavily pitted in the bottom fold except a section that I was able to cut out of. I will use this section below (black sharpie) for the repair piece.
What I am after is having the step detail of the lower part where the floor attaches to the long (red arrow).
Click to view attachmentSo here is the plan; joining the retrieved good part on the right to the left half with the oval hole. Not only will this replace the heavily pitted metal, it will also take care of a lot of swiss cheese. The hole for the seatbelt will be done before joining the two.
Click to view attachmentTo be continued in next post...