Painting the Trunk, Rebuilding Door Hinges the Right Way & Door Fitting Trials

It seems a little odd that the first of the “finished” surfaces on the car would be the inside of the trunk area where nobody will ever see!  But, As we continue to work the plan on this build, that is exactly where we are. 

On the heels of our last update, we began preparing the entire inside trunk surfaces for a nice, even coat of SEM 39144 Trim Black paint.  This process was started by thoroughly scuffing all of the trunk interior surfaces with red Scotch Brite pads to give the surface the tooth required for good paint adhesion.  Once the scuffing work was complete, the entire trunk area was scrubbed clean using cheese cloth and paint prep solvent.  This process ensures all of the dirt grease and wax are completely removed before any paint is applied, and the cleaning process was repeated (about 3 times) until the cleaning cloth remained clean after a thorough scrubbing of every surface.

After tacking off the trunk, the surrounding surfaces were carefully masked off to prevent over spray and we started mixing the SEM Trim Black paint in preparation for our first “cut-in” coats.  SEM Trim Black is, by definition, a single-stage paint that is simply mixed with a proper thinner and applied.  It sprays very nicely and dries to a very pleasing semi-gloss (almost flat) black that is perfect for interiors, trunks, etc.

We started painting the trunk from the inside, paying particular attention to the upper surfaces and all of the detailed nooks & crannies that would not be easy to reach through the trunk opening.  This technique ensured excellent coverage of all of the interior surfaces with no unpainted primed surfaces showing through.

From there, the remainder of the trunk surfaces were treated to three medium-wet coats of paint and allowed to dry overnight before the masking was removed. Then, another 48 hours of dry time was allowed before we began fitting the restored trunk hinges and installing the trunk lid and latch hardware. 

Next on the agenda was the rebuild of the original door hinges.  As in most Mustangs of this vintage, the original hinges were miserably worn out and sloppy, allowing the doors to droop ½” or more when opened.  Generally speaking the hinge pin size is marginal at best for the weight of the factory Mustang door and the design allowed for the hinge to flex quite a bit, adding to the wear rate of the hinge pin bushings.

Fortunately, there is an excellent hinge rebuild kit on the market that I highly recommend from Mustang Steve’s in Ovilla, TX.  Steve Wilkes has done the Mustang restoration community a HUGE favor by engineering an excellent product that cures ALL of the door hinge inadequacies in one shot.  This kit uses larger hinge pins with grease fittings to allow pressure lubrication of the pins with proper grease, larger and longer Oilite bronze bushings for added durability and load capacity and steel reinforcement tubes that stiffen the hinge considerably and provide a reservoir for the grease.  While these are absolutely not “bolt-on” repairs as some drilling and welding is required, the repair work isn’t hard, and with a little care, the entire hinge set can be rebuilt in an afternoon.  Love these!

With our better-than-new hinges ready to go, it was finally time to dust off our new door shells and see how close they would fit and how well our hinges would work.  As this was intended only as a trial fit, and mostly a hinge fit and operation verification, we didn’t yet go through a formal door fit procedure, but for the most part, the new doors hung surprisingly well for what little precision was applied to their installation.  In the end, I am pleased to report the hinges worked beautifully and each door swings silky smooth and without the slightest hint of sag.

So, how important are tight, accurate and smoothly operating hinges on a project like this?  Consider this:  If the bushings in the door hinges allow only 0.010” of slop at the hinge pins, the movement at the back of the door is almost 3/8”!  Now imagine how bad this sag would be if the bushings in the hinges were completely worn away like in our example!  Good hinges are a BIG deal and this kind of rebuild will pay enormous dividends down the road so ever cent spent here is worth untold dollars in time saved down the road.

As a natural progression, we will head into Winter here in Michigan with our focus on fitting, gapping and smoothing the doors, cleaning up and priming the rockers and getting all of the surfaces in high-build primer for finish work later in the Spring.  That is a few hundred hours of work ahead, so we’d better get cracking!

After scuffing, cleaning and tacking, the trunk was fully masked in preparation for the application of three medium-wet coats of SEM Trim Black, single-stage paint.

 

SEM Trim Black is our choice for trunk and interior paint and works very well as a touch-up for under-car as well.

In just about any condition we normally see, this SEM SR204 reducer works extremely well in our turbine HVLP spray equipment.

  

Three coats down and the trunk looks fantastic!  This shot also shows how very little over spray exists when our turbine HVLP system is dialed in.  Very little over spray on the masking and nothing on the floor or body cart.

With the masking removed, the trunk finish looks great!  We allowed a few days for the paint to cure fully before making any attempts to install the hinges and deck lid for fit.

 

With the restored hinges in place, the trunk finish really looks nice.  Too bad this sort of detail will never be seen when the car is completed.

With the rear seams completely sealed, the end caps and deck lid reinstalled, the back end of the car is starting to look very nice.  We will reinstall the valence and get everything in place to begin final filling and blocking when the time comes.

 

After a quick trip through the blast cabinet for clean-up, the door hinges are prepared for rebuild.  The Mustang Steve's rebuild kit contents are shown in the center of the photo.  Though not obvious here, the hinge kit includes new, greasable hinge pins, larger oilite bushings and reinforcement tubes.  If you look closely at the hinge on the lower left, you can see the original bushing sleeves have broken completely away from their flanges and offer absolutely no support to the hinge pin.  We are gunna fix this!

 

There are lots of ways to remove the original hinge pins.  Our preference is to carefully mill the expanded end of the pin off and then drive the pin free with a drift.  This has proven to be the least damaging of all methods we have tried and worth the time and effort to set up.  Also, note the sharp and unfinished edges of the hinge stampings.  This just can't be left that way and we will smooth up these surfaces as part of the rebuild.

Once the hinges are apart, a fair bit of time is spent smoothing every edge and removing all burs from the hinges parts to ensure they are smooth and clean before being rebuilt.

 

After another trip through the blast cabinet, the hinge pieces look far better than what they did when we started.  In this condition, we can now rebuild the hinges with the confidence that they will look as good as they will work once completed.

By just following the instructions to the letter, the lower left hinge is completed and looks as good as it works.  One change we made that is not shown here is that the angles grease fitting was replaced with a straight fitting for a cleaner look.

Here is an upper hinge fully rebuilt and ready to go.

A full set of hinges cleaned, smoothed and rebuilt to better-than-new condition.  These hinges should now last a lifetime.

The newly rebuilt hinge sets allowed us to (finally) test-fit the new door shells to the car.

Out of the box, the test fit of the doors went fairly well.  There is still a lot of work required to get the door fit to be where we want it, but the first fit is promising and the door swings beautifully on the hinges.  Far better, in fact, than any factory 70 Mustang door ever!

Lots of Little Things Really Add Up!

Since our last update, the flow of work has shifted to tackling a series of smaller individual jobs that have quietly added up to some significant progress.  From powder coating, to seam sealing to sanding and priming, the jobs have been many but the results are quite satisfying, in spite of the interruption of some bits of customer work and some family travel “day trips”.

Since we left off, the focus shifted to doing a bit of powder coating that included finishing the trunk hinges as well as the front spring covers which had both been lying about in bare metal for months as we worked around them.  Fortunately, we had reached an opportune moment that allowed these parts to be cleaned up, primed and powder coated in short order and they turned out fantastic.  I must say that having a small powder coating facility in-house makes this sort of thing a welcome luxury that yields fantastic results.  The hinges will remain in satin black powder coat finish, but the front spring covers will eventually be scuffed and coated with U-Pol Raptor bed liner material to match the coating finish on the fender aprons.

Next up, attention shifted to preparing the bottom of our stainless steel fuel tank for a few coats of primer that will act as a solid base for the Raptor liner to be applied on the bottom tank surfaces.  Like the spring covers, the bottom of the fuel tank will be coated in Raptor to match the underside of the car and blend the tank seamlessly into the underside of the car.

The process begins with a thorough degreasing of the tank surfaces followed by a gentle scuffing of every nook and cranny with 150 grit paper to provide proper “tooth” for the PPG DP40LF epoxy primer.  Then, the tank is cleaned several times with prep solvent to ensure a clean surface remains.  And after a quick tack off for remaining dust, a few light coats of primer were laid down and the tank set aside for a few days to allow the primer to dry thoroughly before lightly scuffing the surface with red Scotch Brite in preparation for the Raptor liner material.  However, this will have to wait until Spring as there is a lot of other work that needs to be completed before being able to shoot the Raptor.

Next up was a load of seam sealing duties to get the back of the car sealed up along with the quarter window trim frames that could finally be reinstalled on the car.  These a delicate and often lost little pieces that are often overlooked in a restoration, so I was very careful to bag and tag these parts to make absolutely sure they would return to their proper place.

And so, with all of these smaller “support” jobs complete, the next few weeks will be focused on getting the trunk area scuffed and prepped for the application of a few coats of flat black.  Even though 99% of these surfaces will never be seen, the consistent black finish will work to provide uniformity to the area and act as a camouflage around the areas where the trunk upholstery panels must allow component access or freedom of movement.  Nothing worse than seeing grey primer in the hidden areas when the trunk is open!

Until next time!

 

Original trunk hinges hanging in the powder booth with a fresh application of epoxy powder primer.

With the primer cured, the color coat of satin black was applied and sent to the oven.

Fresh out of the curing oven, the black powder coat looks quite glossy. 

After a few minutes of cooling on the rack, the black powder coating takes on a perfect satin sheen.

The front coil spring covers also get a good coating of epoxy powder primer before being coated in satin black.  Powder coating really does a nice job getting into very hidden places that sprayed liquid paint simply can't go.

It's almost a shame that these covers will eventually be coated in Raptor spray bed liner to match the rest of the surrounding panels!  This satin black powder coated base looks smoooooth!

 

What do you do with a nicely polished stainless steel fuel tank?  Sand the hell out of it of course!

 

Our stainless fuel tank is fully sanded and degreased and ready for masking.  We will be priming the bottom of the tank in preparation for a few coats of Raptor spray bed liner material so the bottom of the tank perfectly matches the bottom of the car.

 

A little bit of masking and we are ready to shoot!

 

Two medium coats of PPG DP40LF epoxy primer will provide an excellent base for the bed liner material to adhere to.

After leveling and preparing the flanges and joints around the back of the car, the areas are masked off for a light application of primer to cover any bare metal spots that were exposed.

With all of the seams sealed in primer, we are ready to apply the 3M urethane seam sealer.

 

The 3M urethane seam sealer floes very nicely into the joint and is easily smoothed with a finger wet with a bit of xylene solvent.  I prefer a clean, smooth seam sealer job over the factory brushed look, even though most of the seams will never be seen.

  

The quarter window flashings were installed and seam sealed after receiving a coat of epoxy powder primer.  These little bits are often lost during restorations of 69-70 Mustang fastbacks and are not easy to find.  These aren't going anywhere!

 

Live Updated Photo Grid From Instagram Added to Page!

Hi folks!  I just wanted to let you know that we have added a live updated photo grid to the top of the blog page so you can see the work we are doing "on the fly" instead of waiting for the less-frequent full blog updates.

Hopefully, our blog followers will find these "flash" updates entertaining and valuable and help keep the information stream flowing a little easier as the Night Mission Boss 302 continues to take shape!

Let us know what you think!

Follow us on Facebook & Instagram!

Hello from the shop fellow bloggers & hard-core auto restoration enthusiasts!  I wanted to personally invite you to visit and "Like" or "Follow" our Night Mission Boss 302 pages on Facebook & Instagram.

We post short progress updates more frequently at these two social media outlets.  It's a quick and easy "on-the-fly" way of keeping the information flow on the project coming your way!  So please feel free to visit our pages and drop us a comment or two and if you like what you see, please "share" our pages with your friends!

Thanks!

Sven

Rear Body Detail Work & Hi-Build Primer Application

They say that “slow and steady wins the race”.  However, for a guy who has been in racing and performance cars all his life, THAT is a very LARGE pill to swallow.  A pill roughly the size of a men’s size 14 Reebok Hi-Top in fact, but as wiser men than I have counseled over the years, patience will pay off and I trust in that.

With the end cap gaps set earlier on, it was time to invest a few hours leveling the remainder of the end cap surfaces.  Oddly enough, these die cast alloy parts are actually very wavy and rippled and require quite a bit of massaging to get them smooth and contoured correctly.  In fact, just about every surface of these parts requires a thin application of filler and repeated blocking to get them straight.  Fortunately, the end caps I have were reasonably good and very little filler would be required to get them in top shape.

Next, with end cap and valence gaps looking very tight, a few hours was dedicated to getting the forward edge of the trunk lid gapped exactly as I wanted and the contour matched to the trunk lid.  Since the trunk lid and lower rear window panel will maintain the classic Boss 302 trait of flat black paint, these edges need to match well to not look out of place. 

With very thin applications of Evercoat Ever Gold glaze, the surfaces and edges of the trunk edge were brought up to match the trunk lid edge very well.  With a bit of hi-build polyester applied, these areas will be able to be perfected with careful block sanding.  Also, I permanently glued specially machined spacers to each end cap mounting stud that ensure a precise gap is maintained.

Following the end cap work, we transitioned to the task of tidying up the flanges that mate to the quarter end caps.  As stampings, these surfaces were anything but straight and flat and the factory made up for this by using a thin rubber gasket between the end cap and quarter.  Since these end caps have been custom fit with a thin gap, these gaskets no longer work (or even exist) in the project.  So, extra time must be taken to carefully fill and flatten these flanges to ensure the finished gap is straight and even from top to bottom.  Yep, more work that you will never see, but the end result is what it’s all about!

The focus was then shifted to clean up the flanges on the back side of the rear valence to ensure the panel gap is properly presented and the edges of the panel are clean.  I prefer to use a product called Duraglas by USC for this type of work as it is completely water proof and works very well as an edge reinforcement with its fiberglass-strand reinforcement directly in the mix.

The final detail work to be completed before masking for hi-build polyester primer was to smooth the rear fender arch flanges to complete the look we are after in the detail areas.  Most factory Mustang fender flanges are nasty bits of jagged metal and lumpy spot welds that look awful with even the finest finish applied.  A lot of cars have fender opening trim that somewhat hides these flanges, but Boss 302’s never had that crap on them and therefore, these had better look tight!

Moving forward, the time had come to scuff all of the rear body surfaces with red Scotch Brite and 150-grit paper to provide plenty of “tooth” for the hi-build primer to grip.  Now, it was time to start the slow process of masking every edge at the rear of the car to prepare for the application of two medium coats of PPG Shopline JP-205 polyester high build primer. 

I have come to love the convenience and time-and-material savings offered by the use of a professional masking machine for masking jobs like this.  A masking machine is simply a device that applies masking tape along the edge of a roll of masking paper and has a cutting edge along the bottom to allow the user to quickly tear off the desired amount of pre-taped masking paper.  All told, I reckon this device saves between 50 and 75% of the time that would be required to apply masking tape to the masking paper by hand.  Worth every penny!

Finally, the application of two generous coats of PPG Shopline JP-205 was upon us.  As primer products go, JP-205 might just be the closest thing to magic in a can there is!  Essentially, hi-build primer is a sprayable polyester body filler that is easily sanded.  By coating the entire panel in a thin, even coat of filler, the panel can be virtually perfected with every contour and body line capable of being as crisp and clean as the most perfect example anywhere.

Like regular body filling techniques, applying and sanding hi-build is an iterative process that relies on careful blocking with guide coat to ensure that every panel detail is perfected.  Once the body is essentially perfect, the hi-build is sealed with epoxy primer and the plans for base color and clear can be established.  Nope, this ain’t no “collision shop” operation here!

On what might end up being the last decent day of what remains of 2014 here in occupied Southeast Michigan, all of the subject panels were squirted with hi-build and allowed to dry for a few hours before the masking paper was removed.  The end result was a nice, contiguous base that will be ready for slow and meticulous block sanding to flatten every surface and them more and thinner applications of hi-build until the entire works is as close to perfect as I can manage.  However, in the meantime, we will let these surfaces cure for a few weeks while we begin to evaluate door hinge rebuilds, trunk hinge powder coating and some seam sealing.

Happy Fall everyone!

The die cast end caps on my 70 are actually pretty good examples.  But plenty of filling and sanding is still required to get them straight and smooth.  Evercoat Ever Gold glazing putty is my filler of choice for detail work like this.

 

Ted blocking out the end cap after a thin coat of glazing putty.

 

This shot really gives you an idea of how much work goes into getting all of the rear contours just right and how much variability there really is in the "factory" rear bodywork of these old cars.

 

The left side was actually a wee bit better overall than the right, but still requires a lot of work to get into shape.

 

With all of the detail filling work done and the contours smoothed up, the added character of the thin gap we added between the end cap and the quarter flange can really be seen.

One area that is often overlooked at the rear of 69-70 Mustangs is the outboard transition area between the lower rear window closeout and the rear quarters.  Most cars have a dip in this area as shown by the straight edge above.  A bit of filler is added to this low area on each side and carefully sanded to bring the surface level.

Here is the same area after filling and sanding.  No gap anywhere along the length of the straight edge.

 

Here is another look at the transition area without the straight edge in the way.  Very little filler is required to get these areas right.

To ensure the tight gaps we added to the rear quarter end caps are precise, I machine these custom spacers to the exact dimensions required to maintain the exact gaps every time the end cap is removed and re-installed.  Each spacer is number to match its individual stud as indicated by the numbers on each spacer and at the base of each stud.  Then, each spacer is epoxied to the base of each stud and installed on the car to dry permanently.

 

In this shot, you can see the spacers glued into place with industrial epoxy. 

 

The rear quarter flanges also require careful attention to ensure they are flat and square to match the end caps perfectly.

 

 

This shot shows how much work is often required to get the rear quarter flanges flat and straight for proper panel fit.

 

Using USC's Duraglas fiberglass reinforced filler, I even up the flanges on the back side of the rear valence to ensure the gaps are consistent when the panel is installed on the body.

Before masking, every panel gets a light scuffing to give the PPG Shopline JP-205 primer good "tooth" for adhesion.

Using a flexible sanding block with 150-grit paper, Ted carefully scuffs the inside radius areas of the quarters in preparation for priming with hi-build.

 

We start masking from the rear tail light panel forward in prep for the hi-build primer.

 

A professional masking machine makes masking large areas of a car amazingly quick!  We are ready to shoot some hi-build primer!

Starting with the smaller loose parts, everything gets two generous coats of JP-205 Polyester High-Build Primer.

Even with the slightly rough texture of hi-build primer, the deck lid still looks great!

And there it is!  The rear of the car is finally in its first round of hi-build primer and is ready to be blocked.  Lots of work yet to do back here, but this is looking pretty good!