Right Rear quarter trunk corner repair-part 1

It's been a week of craziness.   Christmas coming in a week and a day has my schedule pushed to the max.  Plus we're on "baby watch" for my #2 grandson, which reminds me I need to get him some baby Mustang swag.   I'm slowly checking off the "to-do" list from work and home.   The children's Christmas program was today.  It all came together and went off without a hitch.    Of course, the 3 year old "angels" provided a level of comic relief as they adjusted their wings and did everything else to keep themselves from getting bored.  Afterwards, I headed home somewhat tired and ready to veg out and watch the Colts and then follow that with the Lions.   Somewhere and somehow, I decided to at least get started  on the next repair that I knew was going to be a challenge.

This repair is going to be an interesting one since there is not a repo part for it.  I don't think that a full rear quarter repair had enough metal to do what I  need done...not to mention that it's a $400 plus part.  Granted, I do have some serious "dolly and hammer" work on this quarter, I don't want to replace original metal I don't have to.  I also knew this would tax my metal-working skills to the limit.

The first order of business was to get the car turned around so that the area I would be working on gave me better access.  Thankfully, it wasn't raining.  So I rolled the Mustang outside on to the driveway, did a pirouette, and put it back in the garage front-end first.

The next step in the process was to evaluate how much of the metal I needed to remove.   This is the offending area to be repaired.  It is located on the top right-hand side of the trunk opening on the body as you're standing at the back of the car.  It's a strange place to have this kind of rust damage considering the other side has no rust whatsoever.

I taped off the area to be removed to act as a guide for the cutoff wheel...

I found 2 spot welds and carefully drilled them out. 

Then I took my 3" cutoff wheel and cut around the edge of the tape.  I had to be careful not to cut through the underlying substructure...

It took a little "creative" work to get to the area I couldn't access with the cutoff wheel.  I used a combination of my air saw and a chisel with hammer to persuade to part loose.  The lip got distorted with all the prying and hammering, but this is the offending rusty piece after removal...

This is the underside of the part.  It's pretty rusty.

This is the substructure of the upper right trunk corner after I cleaned it up a little.  It had some rust pitting, but overall was in acceptable condition...

Here's another view looking at the opening from the rear of the car.  The one thing I noticed before cutting is that there isn't one flat contour on the body at this transition.  It has a curve, either concave or convex on every plane.  This will be a fun piece to make.

The next step was to make a template of the area for cutting out the new metal.   I decided to make this in two parts since I don't have the means to make it out of one piece.  This is when a planishing hammer, English wheel, and a stretcher/shrinker would come in handy.   This template was a rough cut of the rear quarter top section

Here is another view.  This is going to be a challenge since you can see the bends in that will have to be formed in different planes. 

Since the lip section of part that I removed was ready to break off, I went ahead and removed it.  I would deal first with the part that would be the outer body section.  I tried to cut it so that as much of the transition radius from the body to the lip remained.  You'll see why later.

Here's the back side of this piece...

I then used the original piece to trace the pattern to make the template more exact to the part.  I cut it a little larger than needed so that I had enough metal to work with..

The next challenge was how to make the lip section that formed the trunk opening.  It had multiple contours.   I took a page out of my old drafting and design days and decided to make the template using an orthographic view.  That takes a 3-dimension object and projects it as a 2 dimension object.  To do that, I carefully flattened the piece which was a trick with the majority of the rust along the edge.  I didn't want to loose too much of the edge and hence the profile of this piece of the part.  When it was flat I traced the part onto cardboard and allowed for the nonexistent edges that disappeared from rust...

Here's the template after tracing and cutting.  Again, I left more metal than needed as just-in-case insurance...

Now the fun begins.   I put both templates into position on the car to see how close (or far off) I was.  For the first cut, it didn't look too bad.  But cardboard and steel don't have the same forming properties.  I'll do the final trimming and shaping with the metal.

Here are the two pieces in metal ready to be bent to shape... 

The first piece I formed is the top of the quarter panel.   Here is the part after multiple trimming with the air saw and 2" air sander.  The black color is after the Eastwood rust converter dried...

This is the same part from a different view.  You can see all the different contours of the part.  Of course, when you shape one contour, it changes the other.  Patience and a deft hand came in handy.

This picture is looking toward the back of the car.  Again, you can see the different contour changes of the body.  

OK.  Since I had the general contour done, it was time to form the radius along the trunk-side of the part.  I didn't want to do a square corner weld since that could end up with a mess...blow through, grinding through the corner, more welding, etc.  This is from experience.  Better to butt weld flat joints than corners on thin sheetmetal.

I had scribed a line when the part was on the car to give me a reference where the radius needed to start.   Then I chucked it in my vice and slowly bent it over using a couple of different body hammers...a pick to start the radius and a flat face for the final forming of the radius.

The challenge was the radius on the corner and the curved section.  I clamped the part in the vice with the bottom of the radius of the corner lip in the jaws.  After starting the lip, I kept moving the part so that I was working through the corner about an 1/8" at a time.   This was really tedious work, especially since I didn't want to loose the entire contour of the part.  Here it is with the edge radius completed...

I used a similar technique on the second piece in forming the near 90 degree angle that transitions from the body to the trunk lip.  It was sharper than it should have been when compared to the "good" side.  To round it out more, I used a 1/2" steel rod clamped in the vice to hammer a bigger radius into the part.  It's OK but I'm still not happy with it.  I'll fine tune it later.

What took time was the forming of the corner contour.   After getting the first bend in the long section, I clamped it in place on the end toward the rear of the trunk and along the flange that would eventually be plug welded to the trunk lip.  Then using a wide end and pointed pick body hammers,  I used the thicker inner trunk structure as my "buck" to hammer the shape into the piece.  This was a progression as I left the end clamp in place and moved the large clamp along behind the section I was working.   This is what I ended up with when I got to the opposite end...

When I got to the corner the metal was "bunching up".   To relieve the metal,  I cut 3 slits with the air saw to allow the corner metal to gather together...



The cuts aren't the best since they were in a location where there wasn't much "meat" in the metal.   I'll weld these up when the time comes...



A little more clamping and judicious body hammering and the shape is getting closer.   Here's another view from the top with the blue "back up" tape removed that was holding the top piece in position during shaping and fine tuning....

Now it was time to marry the two pieces together and see what adjustments will be required.  After adding the radius to the top piece, it took multiple trips to the vice and wood buck block along with good ol' fashion hand bending to get all the proper contours into the part again.   
 

The first mock up wasn't too bad.  I had to grind off the top of the vertical part about an 1/8" to accommodate the radius addition.

The corner was not matching up.  I took a flat-end punch and carefully tapped the radius of the inner piece at the "pie cuts" to get the shape in place.  I also went back to the vice a few times and hammered the corner around the steel rod I had chucked in the vice.   As the corner radius took shape,  the top edge also increase in height.  I then used the 2" sander to carefully contour the metal to match the top piece.  It obviously took several different techniques to get the corner into some resemblance of a proper shape.

I still have some tweaking to do in that corner.   I may also work the radius of the bottom piece so that it isn't as sharp.  I don't want to use body filler to shape the area.  I'd like it as close to the other side metal-wise as I can get.   I know I'll end up with some filler, but less is more.

I realized that I had been in the garage for over 4 hours.  It was time to grab a bite to each and catch up on football scores that were disappointing.  Both the Lions and Colts lost.  At least the Colts still have a shot at making the playoffs.  Considering the changes and challenges they faced this year, it would be pretty cool to see them make it in.

The next part of this little project will involve welding these pieces into position.  I'm still trying to decide how to proceed with that.  I'm leaning toward tacking the two pieces together and then fitting it as a unit into the body.   My other option would be to weld in the top piece and then fit the lower piece to it since it's more critical for the top of the quarter to have the better fit and finish.   I'll have a while to think on it before I get back on it again.   I am anxious to see how the finished product will look, especially when compared to the original opposite side.   Hopefully, there will be no noticeable difference...hopefully.

Right Side Trunk Drop Off Part Replacement - Part 2

For the first of December here in central Indiana, it feels more like the first of April.  The temperatures are in the low 60's with a breeze out of the southwest.  My wife hit the yard to do her final gardening work and I hit the garage once I got home from my Saturday obligations.  I needed to make a trip by Lowes on the way home, which I'll explain later.  But how can you not stop at a place (i.e. Lowes) you drive by almost daily on your way to or from Starbucks for caffeine that has so many things that can come in handy in the garage?  See...I knew you'd agree.  Tools and caffeine.  What a great combination!

This is the first weekend where I had some time to get back on the trunk drop off.   If you remember the last exciting episode, I had the replacement part trimmed to fit.  The next step was to get it installed.   One task I didn't mention before was the treatment of the "inside" of the part, that is the side facing the inside of the outer quarter panel.  After the trim job, I gave it a couple of coats of etching primer after a wipe down with acetone.  Then I gave it a couple of coats of satin black Rustoleum.  I also cleaned the outer quarter flange and gave it a shot of Eastwood's Rust encapsilator.  Then I sprayed the flange with the black Rustoleum.

So that brings me up to today's fun activities.  The trip to Lowes netted a 7/8" hole saw to put the drain hole in the original location since this piece of .... sorry... this repo part didn't have one hole in the right place.  I chucked it in the drill press and in a matter of seconds, the new hole was done.

While I was at it, I measured the dimensions of the square hole that's used to hold a wiring harness clip.  I put the appropriate size drill in the press and knocked that out too.  FYI, it's a 5/16 bit if you run into the problem on your 'Stang.  I used a triangular rat-tailed file to "square" the hole up.  I spent some more time after the picture below to make it look actually "square."

While I had the drill press set up with the bit for the plug welds, I marked the location of the welds.  The factory wasn't especially careful on spacing.  But the anal engineer in me and the welding manual suggested otherwise.

After making holes in the part, it was time to fill up the one extra hole.  I took my punch plug from my collection of slugs and ground off the zinc coating that doesn't tend to weld very nicely.   I clamped the part to my work mate using a piece of 1/4" steel and my copper backup sandwiched between the part and the heavy metal backup.   I started with the back side of the part that would be out of view.  

 After lots-o-tacking and grinding the slug was in.  I flipped it over and did a little more metal finishing.

 

Before I clamped the part in place, I put a cone braided wire brush on my angle grinder and cleaned up the inside of the outer quarter panel so that I could spray the rust encapilator in later.  Then after I clamped the part in place, I used my paint pen to mark the plug weld locations on the outer quarter panel flange.  Then I took it off and used my 2" sander to clean those spots to bare metal in preparation for the plug welds...

Then the tedious process began of filling the plug welds and tacking the butt joint.  I won't bore you with the process since many of you are familiar with the process.  Tack...tack...tack...grind...grind...grind.   See what I mean?

After an hour and a half or so, the welding was close to being done. I will say it was rather challenging to get to that top joint with my grinding tools.  I figure that if I'm not happy with it, I'll put a skim coat of Metal-to-Metal on it.  I really do wonder how many people are going to look under it and say, "Hey, that weld joint doesn't look properly finished.   I'm not building this to go across the block at Barrett-Jackson or Mecum auction.  So too bad.

I rolled the car over to make sure I had good penetration in the lower outer quarter flange...

...and the same on the inner wheel well flange....

I have a repair on one of the spot welds I drilled out in removing the drop off.  I got a little ambitious and drilled through the outer wheel well flange.  I'll go back and fill that later.  It should be a 15 minute job including dressing the  weld.

I got done today and felt pretty good about the progress.  I decided to roll the car into position so I could spray the back side, or inside, of the trunk drop off since I did grind the paint off some of it and the weld burned some of the paint off.   As I'm rolling it into position, I'm looking through trunk into the cavity that the outer quarter and the truck drop off form and...."What is that?  You've got to be kidding me?"   Yup, a pin hole of rust in the outer quarter panel.  Seems like it's two steps forward and one step back. 

I'll hit that area with my braided cone wire brush on my 4.5" grinder.  That seems to do a pretty good job of revealing the crustie rusties as I did in the passenger toe board area.   I also noticed I'm getting to the end of the spool of .023 wire and my Argon/CO2 tank is also getting near the end.

So ends another exciting day of working on the fastback.  The next big step (not counting the pin holes in the quarter panel) will be tackling the rust in the right top corner of the trunk opening on the body.  No repro parts available.  But from what I've experienced so far, it won't be a problem making the new replacement pieces parts myself. 

My wife will be going to Lexington, KY to help my daughter who is 36 weeks in her pregnancy with her first son and the second grandson for me.  I'm hoping to spend time on the fastback while I "bach" it for the weekend.  I'll have to make sure he has some Mustang swag to go home in from the hospital.  After all, you got to start bringing them up right from a young age.  :- )

Right Side Trunk Drop Off Panel Replacement-Part 1

The work on the car came about from a different kind of motivation--frustration.  My Alma Mater, University of Louisville was 9-0 and ranked 9th in the BCS.  Well, the defense decided to take a vacation and let Syracuse route them.  I couldn't stand to watch the carnage and went to the garage halfway through the 3 quarter to work off my frustration.  The quandary was what part of the car to work on.   I still have some weld joints that need to be "touched up" but needed to do more than that.

I noticed I had the right side trunk drop off panel laying on the back half of the rotisserie.  That would be the next project to attack.  I rolled the car to 90 degrees on the rotisserie and locked it down.   Then I needed to evaluate how much of the old drop off to remove.  One of the complications was the ribbing stamped in the panel.  I already dealt with that on the right firewall toe board ribbing and I didn't want to repeat that by trying to match up and weld a seam across the ribs.  My concern was whether I would have enough access to cut out the old panel and weld in the new one.   I did some experimenting with the 3" air cut off tool and had the clearance.  The MIG gun would fit also.  Now it was time to cut that piece out.

The part in question was in pretty good condition on the top half.  The bottom part was where the rust pinholes were.  Since this had already been media blasted it was pretty clean.  

I measured out and drew the cut lines to remove the panel.  Then I got out my Blair 3/8" spot weld drill and began the process of separating the drop off from the lower rear quarter panel.

 The next step was to use the 3" wheel to cut the panel along the cut line.  I did have to remove the rear spring shackle that was in the way.  I had clear access after getting that removed with my 4" electric 90 degree grinder with a 1/8" pipe cutting wheel. You can see the remnant of the shackle on the floor.   After cutting along the paint line, I was able to remove the old panel and not have to match up any stamped ribs...

When a panel is removed, you never know what you'll find behind it.  Fortunately, there was no serious rust other than on the surface.  The inside of the right rear quarter panel looks pretty good, all things considered...

With the original panel removed, it would become the template for the new panel...

I nested the original part stamped ribs into the new part.  There was enough metal for the new panel...
 

However, as I have gotten used to the repro part not fitting or exactly reproducing the the part, like the punched holes that were either not included or misplaced such as the front lower corner....



...or on the bottom right side of the panel...



I included the punched holes in the marking of the new part when I outlined the original piece onto the new part.



What I had was two holes that were not punched, a square hole that wasn't punched, and a hole that was punched that I didn't need and wouldn't work because it would be in the flange that mounts the drop off to the lower rear quarter panel.  Nice.   So now I had to make a patch to fill in this unwanted hole...or would I?

When I was in my previous life as an engineer, I had the need to fill a boat load of holes in my Model A frame and firewall.  Because the plant I worked in had a major stamping operation, I was able to get a bunch of scrap slugs from the NC punch presses.  I hung on to this box of slugs figuring you never know when they may come in handy.   Now was the time to dig them out and find out if I could find one that would work, or come close. 

Here are some of the slugs I had...

Lo and behold, I found one that would fit fairly well... 

 

Not so bad, eh?  Now I have my filler material.

With the hole problem solution taken care of, it was time to start to cutting and trimming the new piece to fit where the old one came out.  I used some rectangular tubing and C clamps to hold the part to my workmate so I could trim off the excess metal...

I left a 1/4" plus of extra material to be sure that I could continue the trimming process to get the new part to fit as closely as I could.

Using my 90 degree angle grinder with a 36 grit flap disc, I carefully removed excess material until I got a really tight fit...

I cleaned the side of the new panel that would be inside the trunk with lacquer thinner.  I sprayed it first with etching primer and then followed up with black rust-oleum.   I cleaned up the flanges on the quarter panel with the 2" air sander and sprayed them with 2 coats of Eastwood rust converter.

 At this point, I needed to stop since my family was celebrating my wife's birthday Saturday evening and I needed to get my chef hat on and hang up my welding cap.  I hope to get this on the car sometime in the next week, but I'll need to drill out the holds for the flange plug welds.  I'll also need to fill the offending unwanted hole and drill out the new hole.  The one that's mislocated is not that far off.  So I'll leave that one alone as it's not worth the effort.

Hopefully, by the next update, this part of the body restoration will be behind me.  Then it's on to the next rusty section.  One of these days, there will be no more.  But I'm not holding my breath.