[A&A Models] 1/72 - Dassault Mirage IVA (miva)

Bonjour à tous,

>> Lee Coll :Incredible work. Well done !
When I was a photographer in the Armée de l'air, I sometimes had to take pictures inside the Mirage IV. To get in I often had to crawl inside the air intakes to reach the jet engines ... or, at other times, crawl into the exhaust nozzle.

Traduction : Quand j'étais photographe dans l'Armée de l'air, je devais parfois prendre des photos à l'intérieur du Mirage IV. Pour y entrer, je devais souvent ramper à l'intérieur des prises d'air pour atteindre les réacteurs... ou, à d'autres moments, ramper dans la tuyère.

The final set of images relating to my obsession with adding/replacing inlets etc.  On the forward underside there are three or four louvered inlets more or less on the aircraft centerline.  I 3D printed small 2mm x 3mm insets to represent these.  The first photo shows marking the placement areas where one of the Eduard brass scribing templates (2 x 3) was used to scribe in the inset perimeter.  This was filled in with ink to make it more visible when I drilled and carved it out.


The next image shows the insets in place, being careful to align them on the aircraft's axis. To keep the inset plugs from falling into the model, I typically have some back support and a bit of epoxy putty there to allow me to support it and set it flush to the surrounding model surface.  Filling will be done with more epoxy putty, smoothed in with a small wooden chisel made from a toothpick.  Keeping it wet (the chisel) prevents the epoxy putty from sticking to the wood tool.

And the item directly ahead of the radome position.  I also use some brush-applied surfacers like Tamiya Grey primer or Mr. Surfacer 1000 to fill in any small gaps before carefully sanding the surrounding area flush.


This final image shows the insets after some initial priming with MRP Fine Grey Primer.  I use it because it doesn't build up thick coats like other primers, and won't clog the small louvers when applied.  This reveals there is still some filling and touch-up to perform, again with brush applied surfacer then polished smooth once dry.  Note that the louver slots are less than 1.5mm across, so the ugly close-ups will look much better on the actual 1/72 model.



Happy Modeling!

Lee

Hello!
very nice work
I especially like the louvres!

Hi Lee !

Just discovered your thread and it's a pure pleasure to follow !
Your work with 3D printing is spectacular .
Cheers

Both drop tanks have drains (?) that are recessed circular features that I fashioned from 2mm punched styrene inserted into drilled 2mm holes.  The snug fit kept them from falling into the drop tank and they were set at the same depth by carefully pushing with a wooden rod.  A small amount of Tamiya extra thin cement fixed them in place.

Hello,

Great job, wonderful this 3D's printing home working.

Olivier

Hi Lee. 3D modelling and printing are the next step for our hobby. i do the same here(Mirage VF, MS 500 and others). I saw you use Phrozen printer. I bought one this week and started printing too with it. that's a fantastic tool for modellers. what is the software for design? Solidworks? Do you think we can share our files together? i have many designs here that are supposed to be interesting to you (may be).
Let's continue to make this really great job. And on a French Plane such as a Mirage, especially the IV, we are fans!

LaurentJAG a écrit:Hi Lee. 3D modelling and printing are the next step for our hobby. i do the same here(Mirage VF, MS 500 and others). I saw you use Phrozen printer. I bought one this week and started printing too with it. that's a fantastic tool for modellers. what is the software for design? Solidworks? Do you think we can share our files together? i have many designs here that are supposed to be interesting to you (may be).
Let's continue to make this really great job. And on a French Plane such as a Mirage, especially the IV, we are fans!

Laurent,

I am still using a relatively "old" Phrozen Shuffle 2018 model, but amazingly have yet to have issues with it.  I note a lot of the reports regarding the newer printers having mis-prints, but most of these are not dialing in the correct  resin exposure times or due to operator errors.  I print on average about twice a month, and have only gone through 2 x 500ml bottles of the ABS-like resin thus far.

Regarding the software, I do have Solidworks but have yet to use it for scale modeling applications.  I use a software called Vectorworks that I have been using in one form or another since 1998 (When it was MiniCAD), and this is only because my employer used only Mac computers and I needed a CAD program after AutoCAD quit supporting Apple products.  I know a lot of modelers are using Fusion 360, which in it's current state is still free.  I have seen some great work created on F360 for modeling applications.

I have been asked by a friend if I could compile all of the relevant STL files associated with the Mirage IV project, and I plan to do that, to allow it to be scaled to 1/48 for the Heller kit.  Once I do that I can share them with others under the condition that they are not used for commercial purposes.  

Of a related note, the usual ABS-like resin really works well for details and that's what I've printed with thus far.  The only problem is that it can be very brittle and I have ruined parts just taking them off the supports.  I am concerned about the main landing gear that I have still not printed eventually failing under the shock of it just being set down.  So I am going to use the new Onyx Pro410 made exclusively for Phrozen by Henkel that can be used for load bearing and working parts.  I hope to have those done within two weeks.

Lee

Hello

Ne pas hésiter à partager des fichiers ou travaux d'impression 3D par ici:
Do not hesitate to share 3D print works here:
https://fighters.forumactif.com/f186-modelisation-et-impression-3d

Hello Lee,
Excellent work

As I approach the major stage of attaching the wings to the fuselage, I needed to address some fit issues beforehand.  The image below shows a considerable gap between the wing and fuselage along the wing root.  It is not consistent in it's width, and I am certain that if I had not stuffed the fuselage with intakes, supports, and all that epoxy putty earlier, that the fuselage sides at the root would be more cooperative in conforming to meet the kit wing roots.  


My solution is to use a non-solvent filler to fill the gap, and in this case it's epoxy putty again.  To keep it from sticking to the fuselage, which it will need to conform to, I install a "dam" out of adhesive metal foil that the putty will not bond to.  My favorite is the Bare-Metal brand, particularly the original Bare-Metal foil that is thinnest and has just the right amount of adhesive.  But I was out of that type, so I used the copper version instead, which shows up quite well in the images that follow.  I applied the foil along the gap on the fuselage side and embossed it gently to assure the surface there was covered.  The putty is to be applied only to the top wing's root area.


I smoothed the epoxy putty into the gap, and then leveled with a purpose-made wooden tool, kept wet to prevent the epoxy putty from sticking to it.  This was pressed into place and allowed to set overnight. The clamps are there only to assure the upper wing remains in the exact position in which it will eventually be glued.


Once the putty is set, the upper wing is removed, and the metal foil is peeled back to reveal only the putty in the place of the gap that was there.  This is then treated with sanding sticks to assure the putty profile matches that of the upper wing, and the root gap is filled.  It is important to prepare the plastic surface to where the putty will bond, or it will pop off.  I sometimes run thin CA glue along there to assure the bond.  As you can see it does a nice job of filling just where it's needed.  Epoxy putty offers the advantage that it will not shrink after it is set, and any errant applications to adjacent surfaces can be scraped or sanded away without the solvency effects of solvent based primers.


This method can be used when installing probes, or pitot tubes, or creating uniform openings on wing leading edges (for guns or pitots).  Size the hole with an available metal cylinder, like the reverse end of a drill bit.  You can use gap-filling CA for this and once set, just twist the metal cylinder out and sand the surrounding area flush.

The fitting of the fins on the drop tanks included printing an alignment guide on paper then glueing it to cardstock or in this case an index card.  The notch on the centerline helps me align it with the tank pylon.  This was glued to the kit part with white (PVA) glue.


The kit fins required some sanding to get all four to match in profile, then introduce an approximate airfoil shape to all edges besides the mating surface.  Using the paper guide, I was able to glue these in place with Tamiya Extra Thin, which allowed some time for adjustment and alignment.


These are left to dry overnight after the angles and station were set.  I will run some extra-thin CA glue to strengthen the bond before applying brush-on primer (Tamiya Gray) to the joint and cleaning it all up prior to painting.  My camera angle is a little skewed; when you're right on the drop tank axis it all lines up.

Top precision at every stage.
Your IV , is going to be a state of the art.

nice

Hello Lee,
incredible and excellent work!     

Small update with some minor progress on the external fuel tanks.  I have modified the profile of the fins, as the kit has them incorrectly represented. The outer edge of the fin should be almost parallel to the axis of the drop tank.



They are shown here modified and in grey primer.

Toujours top ce montage.

Your work is still great.

Je suis fan.......

Hi Lee,

Fantastic built, thank you for sharing
You know that all the french modellers are making prayers every day to have a 1/48 Mirage IV released by Tamiya or GWH because we don’t have your skills !

There ´s a wondeful built here thar may help you, if not too late :

https://fighters.forumactif.com/t77674-mirage-iv-a

André

André-François a écrit:Hi Lee,

Fantastic built, thank you for sharing
You know that all the french modellers are making prayers every day to have a 1/48 Mirage IV released by Tamiya or GWH because we don’t have your skills !

There ´s a wondeful built here thar may help you, if not too late :

https://fighters.forumactif.com/t77674-mirage-iv-a

André

Andre - and I took up the 1/72 scale A&A kit because I imagined it would provide an easier route to a nice Mirage IV, as compared to either Heller kit.   I have the Heller kit in 1/48 and have seen the fine work on this forum as an incentive to build as nice a replica.  If one of the reputable manufacturers from the east would do 1/48 French post-war or modern subjects, I think then they would all do them.  But I would also settle for a Heller revival with new tools on their classic best sellers.

And the 1/48 project you'd linked to is one of two I've followed and gained a lot of inspiration from. If I had decent drawings of the ECM pods I would do them in 1/72 for my own project.

Regards,

Lee

A brief update following a quiet and non-productive modeling period.

Before closing up the Mirage IV fuselage with the bottom wing, I needed an accommodation that would assure the alignment of the exhausts.  I did this with a second 3D printed "spectacle" section, that was backed up by a carved piece of RenShape/Ureol that had holes drilled on the centerline of each exhaust.  This would allow me not only to align the axis of the engine exhausts and set them at the same station.  The carved item forward of the spectacle section provided the means to insert a handling fixture to keep the model upright during the remaining progression of painting.


Another image of it all installed: