Project Minne - a 72 build thread

[jpnovak]

September 2018

After the bumper has been reworked it needed some Orthodontic work. The oil cooler width is about the same as the hood vent parting lines. This made it easy to pull a straight line down to the bumper and help locate the opening for the cooler. Special thanks to Jed and Jim for some great discussions on the visual design related to pulling this off.

The hood lines were extended with tape to provide an outer edge limit for the oil cooler vent opening. Then I mocked up the cooler opening with a sharpie, tape and razor blade. I chose a radius corner slots that left a highly rectangular shape. At some angles the mockup for the opening looks almost trapezoidal but this is due to the downward and inward slope of the bumper above the lip.



Once I settled on the design (I slept on it over night) I just had to commit. Cut it out and hang it up. I opened up the mouth on Minne. And her braces (the oil cooler) show through. Of course, Now I have to lower the oil cooler slightly to maximize airflow through the fins. I am a little concerned about the hose inlets and will deal with that next.

[jpnovak]

During the time I was working on the bumper designs I am also starting to prep the tub for primer. Recent increases in body shop cost mean I will probably paint the car myself. I just can's spend the amount of money that I have been quoted for paint. I can't spend what I don't have.

Prepping the tub means spending time with wire wheels, sanders, grinders and a long list of various tools to get down to clean metal. Despite having the tub blasted there are still remnants of old undercoating, slight surface rust (it has been 3 years) and other things to clean up. Here is an example of the pile I swept up after cleaning out one rear wheel well. Lots of undercoating there.




In the end the car is starting to gleam. My profiled fender lips look good and I am happy to be close to primer on some sections of the car. I just love the look of raw shiny steel. Funny that several local friends have commented that I should just clear coat the car as is. I admit my body and metal work skills are not nearly good enough to just clear coat the car.





Hopefully the next installment will have a body in white.

[jpnovak]

In the previous installment I made a hole in the front bumper to feed cool air to the oil cooler. Also have to make the rear match.

The rear of the car has a lot of hot air. The rear bumper acts like a sail to trap this hot air at speed. Hot air under the car creates lift. I am not running any tail so I want to minimize lift. There are many examples of "speed holes" that match this physical description. I just wanted some continuity between the front and back. So, the shape has the same the front - rectangular with radius corners. Both openings have the same radius.

Here is the mockup of the rear mesh. I had to install (tape in place) a license plate from my stash of old plates in order to get a visual. The overall shape is masked out in tape. This makes it easy to change.



I had to make tabs to support the plate. The plate will end up being on standoffs about 1/2" long. The goal here is function heat extraction.



ONce marked up the outer perimeter is outlined with a permanent marker the tape is removed and the cutting begins. The straight cuts were made with a cutoff wheel. The corners were cut inside the line using a jig saw. Then the final shape was sanded up to the line being careful to keep the straight. I wrap paper around a large socket to sand the corner radius.

The finished opening looks remarkably Singer. It shows they have good taste. I have sketches of this style going back a few years when I started this project. Cool.




The opening gets covered with a mesh from the backside. The mesh will be put into place after the bumper painted. For now, its cut and fit.

[jpnovak]

While I was working on the bumper I had to get rid of the muffler cutout. Yes, this big giant hole is cut into the driver's side of just about every early fiberglass bumper on the market. I don't want a big gaping hole when I won't have an exhaust pipe coming out of it.



The first step in the process is to make a buck to support the mold. I took aluminum TIG welding wire and carefully bent this to match the PS of the bumper. Then I flipped them over and taped them into place across the hole. 3 support lines was enough to support the curve across the gap.



Once the buck support wires were in place they were coated in a layer of duct tape. The only roll I could find had bacon on it. Yes, this project will be sizzling hot! mmm. bacon... I digress.

Duct tape is great because curing fiberglass doesn't stick to it. It makes an excellent mold liner material.





The process then follows the same as closing up the front gap. I layer fiberglass in from the backside. The mold support gives it 95% of the shape of the actual bumper.



Once the fiberglass sets I can remove my tape mold. This was 3 layers of glass and it was quite stiff. Remember, More glass fiber, only enough resin to keep it wet.




The fiberglass is then blocked smooth and a skim coat of filler is applied. If done right you will quickly burn through the filler and reach the fiberglass base.



After blocking smooth the surface has the right curvature. A quick coat of primer gives a better view of the repair. Smooth and exactly what I want. There are a few low spots. I will touch those up during the final block phase.

[jpnovak]

September 2018

Its been a long week and I made a lot of progress toward getting the body ready. The other day I was able to shoot epoxy on my bumpers and hood. This means I have a nice stable base to begin the final phase of body work and block sanding. My repairs came out great and are mostly invisible with a coat of epoxy.

[jpnovak]

We have had such wet weather lately I had the fenders and doors almost ready for epoxy. They sat there, stripped naked with only a metal wash on surface waiting for the sun to come out so that I could do a final wash, dry, wipe and shoot.





Today I finally got that chance so I started the final prep process. Water wipe down and wash followed by the DA. There is nothing like bright shiny steel gleaming in the sunlight. Yeah, that metal's clean enough to eat off of. Epoxy should easily stick to it.



I loaded up the spray booth and put down 2 coats of epoxy. My "spray booth" you ask? Ok, the truth is I shot these in the backyard on some sawhorses and one body panel stand. It will all be blocked down so I am not worried about any bits of trash. Thankfully there were none. I did however get a little heavy handed in spots and there are some runs. No problem and easy to fix layer - unlike a color coat.





There was half a gun of epoxy left after the fenders and doors were coated. So I wiped down my tub and coated over the previously blocked bodywork. Oh yeah! it looks so good. Very straight, very curvy, very sexy. Such an amazing feeling to get to this point after so many years.

[jpnovak]

I had some late meetings one morning for work so I decided I had just enough time to shoot some primer onto the tub. The funny thing is that it takes way less time to put down primer than it does to mix it, let it set "cure" in the bucket and clean up afterwards. Ah, such is life for the next few months.






I am using Southern Polyurethane (SPI) epoxy. So far, I really like it. It sprays very easy and is easily sanded to remove or get smooth. Speaking of get smooth, I am following their TDS and putting the body filler on top of the epoxy. I did scuff slightly before the skim coats.

The filler is just a skim coat to smooth over some of the hammer marks on the reshaping of my flares. There is also a repair on the quarter panel from long ago. I metal finished the seam but it still needed a little extra work. All of these coats are less than 1/16".




The roof also had two depressions. I worked them out the best I could but still needed a very thin coat. So, I decided to skim the entire roof. I will be blocking this down over the next day or so.



The best part of body work is that it is quiet. I can work at night when the family is in bed. Nothing but a rhythmic ssshhhttt, shhhhttt, sssshhhhttt of the long board making the surface smooth.

Here is a quick shot of the quarter panel after most of the filler has been sanded down. Its starting to get really straight - exactly why I am going through this process.

[jpnovak]

Since I now have the tub and all the body panels in epoxy i thought it was good to start thinking of the next step. Well, that next step is actually more primer but the final step is color.

I stopped by the paint shop and bought a quart of paint as a tester. I plan to shoot the bumpers in another week or so to see if it looks right. This is a PPG product line carried by my local shop.



Yes, its very tangerine. Yes, I am in love. No I don't think I can wait to get some of this down.

[jpnovak]

Part of the priming process was to complete the oil cooler box. Nothing fancy here, just a sheet metal boxy covered in primer. Next up is some seam sealer followed by a shot of undercoating.



And yes, even after the undercoating the oil cooler still fits. REally, I just needed a spot to hang it. I figured it was safest attached to the body.



I will need to cut two holes in the side of the oil cooler box to insert the AN16 fittings. These still have to be welded into the oil cooler. That's another job for another day.

[jpnovak]

Having all the panels all one color, albeit not the color of the car, was still enough motivation to do a mockup. Let's see, 2 bolts per door, one bolt per fender a few clamps and some gravity to put together a car. Oh, and tape. Can't forget the tape. I think I used just about every fastener in the book.

This means I can go to the track with it now, right?! Surely it will pass tech.

Yes, I am excited to see my project actually looking like a car shape after such a long time.

















Plus, I Have to hang them on the car anyway to start the bodywork process. I am going to start skimming and blocking panels. This will be the long slow process. Will see if I am any better than the last time I did this.