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  • Originally posted by Don View Post
    That is so cool Joel. Lot's of noodling before making the first bend I bet..... Will be very interesting to see how it all comes together.
    Don: Yep, I was thinking about how best to make this piece for about a month before actually taking it on
    Joel Heinke
    Be original; don't be afraid of being bold!

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    • Joel.
      Also, since I posted my Ferrari 348 front and rear calipers arrived. Even though the smallest available F348 wheel available was 17”, these just clear the 15” wheels at the rear (310 discs due to the handbrake drum) and have 5mm more clearance at the front (300mm discs). The F348 calipers are the same as the Porsche 924/928/964/993 4 Pot Brembos. If you consider these calipers on 300mm discs you should be Ok for 15” wheels. They are easily available and come in many different piston sizes. Alternatively, you can use Boxster 986/987 or 996 911 calipers, which are radial mount. Again, these come in different disc widths and piston sizes (these ones are monobloc). Heaps of info on the Pelican Part Forums!
      Last edited by luke.jenner; 10-22-2020, 06:09 AM.

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      • Originally posted by luke.jenner View Post
        Joel.
        Also, since I posted my Ferrari 348 front and rear calipers arrived. Even though the smallest available F348 wheel available was 17”, these just clear the 15” wheels at the rear (310 discs due to the handbrake drum) and have 5mm more clearance at the front (300mm discs). The F348 calipers are the same as the Porsche 924/928/964/993 4 Pot Brembos. If you consider these calipers on 300mm discs you should be Ok for 15” wheels. They are easily available and come in many different piston sizes. Alternatively, you can use Boxster 986/987 or 996 911 calipers, which are radial mount. Again, these come in different disc widths and piston sizes (these ones are monobloc). Heaps of info on the Pelican Part Forums!
        Luke: thanks for providing your knowledge and input. I really appreciate it. My decision on rim size has been driven by two main factors in this order: availability of high perf tires at reasonable cost and clearance for larger brake rotors. So while from an originality point of view I'd like to go with a 15" rim, there are just so few choices for high performance tires in that size and I'm sure the choices will get less over time and not more. With the larger rim sizes, there's lots more choices and I'm hoping it stays that way for years to come. Also, given my Miura is 105% of the original Miura size, I'm thinking the larger sized rim will blend in just fine.

        Again, thanks for the input and keep it coming!
        Joel Heinke
        Be original; don't be afraid of being bold!

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        • Inner door frames (cont.)

          I find myself having an unproductive day, so I figured I’d accomplish something by posting up an update. While I live in the once beautiful state of California, our electricity delivery these days is about as reliable as a 3rd world country. While I do a lot of my metal shaping with hand tools, I still need electricity for critical stuff. Needless to say, I’m not happy with the elected officials that are responsible but it seems that providing a reliable electrical grid is low on their list of priorities. Enough said on that and on with the update.

          I’m working to fill in the smaller nooks and crannies on the front of the passenger side door frame. The plastic piece from the C4 Corvette provides a good reference for this purpose.





          I started by making the “Z” shaped pieces where the door seals mount, shrinking/stretching them to add some curve and then tacking them in place. Then I made the surrounding pieces to fill-in the remaining holes. I try to keep the weld seams away from the corners as much as possible. Here the top area is welded together, metal finished and the bottom area is ready for tacking.



          My plan is to fit up and weld in the piece that goes all the way across the bottom of the door frame next. Here I’m working out a plan for the best join lines to the door frame bottom piece prior to welding up all the adjacent bits and pieces.



          My goal for the door frame bottom is to do it in a single piece; this single piece to include the flange for mounting the outer door skin. I had to outsource to a sheet metal shop the weather seal bends already in the piece but am hoping to be able to tip in the flange myself for door skin mount.

          Now if the electricity would just come back on so I can weld in the waiting bits and pieces to make some progress.
          Joel Heinke
          Be original; don't be afraid of being bold!

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          • Inner door frames (cont.)

            I decided to do a “rinse and repeat” on the drivers side door inner front door frame before I forgot how I did the passenger side. It’s good that I didn’t wait longer as some bits had already escaped my memory and I almost screwed it up. On the second bend, I tried to do it with a ” thick hammer form when it should have been the ” thick form. Luckily, I was able to re-anneal the bend, reform it back to straight, and then use the proper thickness hammer form to put the proper thickness bend back in.



            After metal finishing the welds, the piece came out well. And of course, it took much less time than the first one.

            Joel Heinke
            Be original; don't be afraid of being bold!

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            • Looking amazing Joel.
              308 Ferrari replica
              Prova Countach 5000S

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              • Amazing work!

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                • Joel, What is your method (steps) for metal finishing the aluminum?
                  Remember, there is always next year.

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                  • Miura Station Buck Assembled

                    I had some space open up in my garage and I could use some shape information/measurements in the door area so I decided it was time to assemble the complete Miura station buck. As a reminder, this station buck is composed of 4 modules and I’d only assembled 2 of those modules to-date.

                    Main body module:





                    Rear clip module:





                    I haven’t mounted the rear opening hammer form yet. It will take some work to figure out how best to do that so I’ll wait until it’s needed to do it.

                    Complete station buck:





                    There’s a bit of conflict between the legs on main body module and rocker panel module. The rocker panel module is sitting about 2 or 3 inches aft of where it should be until I do some cutting on stations to remove the conflict. My gut feeling is that I’ll most likely use these modules separately anyway so I decided not to break out the saw just yet.

                    It took about a day and a half to assemble the station buck. It took this time because all the joining slots needed to have the ends squared out, CNC router bits only make rounded corners. Stations in curved body areas needed to have edges round off with router. The station center defines body skin height and station edges in curved areas were above body outline, in other words too high.

                    My impression now that the entire buck is assembled is that the car’s overall length and width will be bigger than I was expecting. That’s not a bad thing; it’s just that I hadn’t yet formed a visual in my head for the actual size of a 105% Muira. Looking at a 3D model rendition on a computer screen doesn’t really give you a feel for the actual size of the car.

                    I had been looking at an original Muira SV last week, knew mine would be larger and now that I have a visual, it’s clear how much larger. I did take overall length and width measurements from the station buck and they are spot on for what they should be. I guess this really shows yet another value from having a full station buck prior to shaping up the body panels. I will now have a more realistic visual in my head as to what the actual panel size should be.
                    Joel Heinke
                    Be original; don't be afraid of being bold!

                    Comment


                    • Originally posted by TRcrazy View Post
                      Joel, What is your method (steps) for metal finishing the aluminum?
                      My approach to metal finishing is different depending on if the weld was made using TIG process or O/A torch. For the piece shown above, it was done with TIG so I'll cover that here.
                      1. The weld itself. If at all possible, weld both sides of the metal. On thin aluminum sheet, it's impossible to get 100% penetration when welded on only 1 side. There might be some guys with very fancy equipment that can achieve this but not an amatuer welder in the home garage. Without 100% penetration, when you remove the pride from the weld bead (i.e. make it flat to the sheet) you end up with a weak weld that has high probability of cracking over time. When possible, I make the first weld pass on the backside of the piece. When making the first pass, filler rod is required and thus you get a proud weld bead. For the second pass on the other side of the piece, I do a fusion weld (no filler used) and only use filler rod if needed to bring a spot up to level. By using this approach, the proud weld is on the backside (which I try to leave for strength if there's clearance on backside) and less metal to remove on front side when metal finishing.
                      2. Grind or file the weld for metal removal. I typically use a 4 1/2" angle grinder for the bulk of weld bead pride removal. I use hard grinding disks made for aluminum. I have a rough grit disk and a finer grit disk. If there's much metal to remove, I start with the rough and finish with the fine. If not much, just start with fine grit. You have to be careful not remove too much metal or leave gouges as these disks can make a mess of the soft aluminum if not used with care. Alternative to grinding disks are "Vixen" files. I tend to use the Vixen files more on O/A torch welds but do also use them sometimes on TIG welds.
                      3. Shape/round off corners, curves, etc. I use fine tooth files to shape and round off outside corners where the weld bead crosses them. I use fine round files for inside corners. These files tend to clog quickly so you need to clean with file card often.
                      4. Smoothing/Finish up. I use a 2" Ro-Loc sanding disk on a small, handheld 90 degree air motor for final smoothing. I usually start with 60 grit sandpaper and work up to a finer grit like 120. I also find using 180 grit on a small sanding block to be helpful for flattening out and also dressing up curved areas/corners.
                      Good metal finishing takes a lot of time, probably as much or more than welding time. My parting advice is, put on some good music and take your time. When I rush, the results are never as good.
                      Joel Heinke
                      Be original; don't be afraid of being bold!

                      Comment


                      • Front clip interface to passenger door

                        Now that I have the station buck main body module assembled, I was able to get the location measurements for the door top. Till now I had been assuming the top front of the door skin would be at the same height as where it was on the C4 Corvette door frames. Turns out it’s not and that’s going to cause a small amount of rework. Oh well, better to catch it now than later when it would have been a lot worse.

                        The top front corner of the door skin on my Miura is going to be about ” higher than it was on the donor C4 Corvette door frame. The main difference is the C4 door skin started at a lower height and angled slightly upward as it went across the door. The Miura door skin starts higher and is level across the door until it makes the dramatic upward swoop that’s the signature of Miura doors. So I need to remake the front clip inner structure where it forms the front door gap for a smooth transition to the door top.

                        After cutting the weld and discarding the old, I started with cardboard templates and making a new sub-structure for the front clip skin.







                        The tricky part is that there is no door gap at this point. I didn’t want to trim the front inner door frame yet as invariably I’d make it too short. So I had to work with the door open while positioning and test fitting the front clip substructure. I used a cardboard template made from the station buck to get the proper shape and curvature in the substructure and adjacent door frame. I then trimmed the substructure for the desired door opening outline, then marked and trimmed the door frame to get a 1/8” gap. A wider gap will be needed prior to mounting body skins but I wanted to test for contact on door opening with a small gap.



                        The good news is that there is no contact in that gap area as the door is opened even with only 1/8” gap. This confirms that the door hinge outward repositioning was successful!

                        Now I can proceed making the top part of the inner door frame and have a defined target on the front clip substructure to work to.
                        Joel Heinke
                        Be original; don't be afraid of being bold!

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                        • Looking awesome Joel

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                          • Door frames (cont.)

                            I proceeded to shape the upper part of the passenger inner door frame. It’s a bit of an odd shape and I wanted a smooth flow from the lower portion of the frame. Unlike on a normal car, this part of the door frame is directly visible when the front clip is raised so it needs to look good. I made up a cardboard template and ran it through the bead roller to tip the edge similar to how I anticipated making the actual aluminum one. Not to surprisingly, my first attempt at making the piece in aluminum sheet was not quite right and became the latest piece added to scrap bin. My error was too large of a radius when tipping in the bend line in the curved section.

                            The second attempt came out great. Here it is welded in place.



                            And the front visible side…



                            The lessons learned from the first attempt that was scrapped. Anneal along the tip line prior to doing any tipping on it. I used a 3mm radius tipping roll so it didn’t mark the panel too much while heavy pressure was being put on it to form the bend. The shaping process worked best when alternating between shrinking the curved edge area and forcing the bend tighter via tipping.

                            And after successfully making the passenger side, I repeated the process for the drivers side.



                            Of course, this side took less time and the shape is cleaner.
                            Joel Heinke
                            Be original; don't be afraid of being bold!

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