Jump to content

Mirage IIIO 1/32, Scratchbuild

Recommended Posts

Simple processes and complex shapes


I am making fairly good progress on this project at the moment so it's time to post again with a few more bits and pieces , none of which have anything much to do with one another.  The one thing they have in common is that the shapes might look difficult but in fact are really just the result of simple processes repeated.


First the shock cones.  The photos are fairly self explanatory.  Once again I'm very happy I have access to a wood-turning lathe.



I think I'm getting the hang of this woodturning business...



I even managed to make two sets of shock-cones that looked like pretty close matches.  These shapes are quite specific and might look tricky but with the right tools - i.e. a wood lathe - they are actually not that difficult to produce.



Once they were sliced down the middle and the excess unwanted half was sanded away they both fitted quite nicely into their respective air-intakes.  



Having recently cut out the forward undercarriage bay my mind was focused on ensuring that this model would not become a tail sitter. I've already added some forward weights but decided there was still some doubt and I just don't want to take that risk... sooooo....


I took the central section and cut two guiding cuts along the inside of each half...



then carved out a wide slot along the entire length forward of the main gear.



Into those slots I fitted two strips of roofing lead and then glued them into place with two-part epoxy.  


I am now fully confident that this model will not sit on it's butt. :thumbsup:


However at this point I realized that the shape of the forward undercarriage bay was wrong. Currently there was nowhere for the wheel to fit when retracted. 



So it was back to some fretsaw and chisel work to cut out the deeper recess in the UC bay that sits directly behind the ejector seat.


Obviously the UC bay is very rough at this point but this will be easily sorted by lining it with either sheet plastic or brass.  


In the meantime each of these  central fuselage bits consist of quite involved geometry and are perhaps the most complex single-piece shapes I have ever modelled.  However, even though the parts are quite complex, they have not been especially difficult to produce. This is because they are just the result of several simple exercises in cutting and carving carried out in sequence. This is a variation on a theme that @hendie often espouses 'even the most complex pieces are generally just a series of simpler pieces stuck together.'    Very true.  Generally speaking this scratchbuilding business is just simple processes repeated to make complex shapes.


Stay Safe modelling folks!

Bandsaw Steve


  • Like 12
Link to comment
Share on other sites

10 minutes ago, Bandsaw Steve said:

this scratchbuilding process is just simple processes repeated to make complex shapes.

I'm starting to understand this better, it seems like it should be obvious but for me it really wasn't! 


You're building up a head of steam on the build now. The work looks fantastic and you seem to be having great fun. 👍 



  • Thanks 1
Link to comment
Share on other sites

There is indeed an underlying simplicity in all of this work.

Someone once told me that in woodwork there are only two tools:


- A hammer (for applying impact forces)

- A chisel (for cutting things)


To which I replied, ‘what about a saw?’ And he said that a saw blade is just a row of chisel-heads. A sheet of sandpaper is just a bunch of tiny chisel-heads glued onto paper. A wood-plane is just a chisel-head set in a frame, a drill bit is just a chisel that rotates and so and so and so…


Of course at one level this contention is plainly absurd, but there is an underlying truth here; in woodwork (short of gluing or nailing things together*) there is only one way to get the shape you want, and that’s to remove unwanted material with some form of cutting tool. So fundamentally the whole discipline of woodwork comes down to a very simple premise. Start with more wood than you need and use a sharp edge to remove the stuff you don’t want! 🤔


That’s it really! 😱



*in a way a nail is just a chisel too. 



  • Like 7
Link to comment
Share on other sites

1 hour ago, RichieW said:

You're building up a head of steam on the build now.

Um, he and BBS have already done the Hogwarts Express. 😁 But I agree that he's got his momentum up. 🙂


1 hour ago, Bandsaw Steve said:

Start with more wood than you need and use a sharp edge to remove the stuff you don’t want!

I've heard a similar method described on how to carve a statue - start with a block of stone or marble and chip away all those bits that aren't a statue!


But I agree with the premise, that complex bits are simply a collection of simple bits.     She's coming along well, Steve. Regards, Jeff.

  • Like 1
  • Thanks 1
Link to comment
Share on other sites

I've espoused many things in my time, and generally, they're all simple. I try and keep it to two syllables at most otherwise it gets complicated. :D

Nice chiseling Steve.  The way your skills are progressing you'll be able to knock out a helicopter soon. Now, that will be a build to watch.

You're right though - pretty much everything can be boiled down to simple.geometric shapes. The trick is to recognise which one is simplest and start from there, building (or subtracting) one simple shape at a time.


  • Like 3
Link to comment
Share on other sites

It's always a pleasure to see how you work and the result, with your pics and explanations it seems sot easy, virtual making are always simple and easy but in real life it's not the case 😉

Great work and very realistic on the intake and the "souris"

  • Thanks 1
Link to comment
Share on other sites

Simple Shapes and Complex Processes.


In the last post I talked about simple processes making complex shapes.  This post is sort-of the opposite. Here the task of making a simple hole demands a few more steps than I anticipated.


Plan 'A' looks fairly straightforward - just get a 25mm spade bit and drill out the rear-end as shown. 



When using a spade-bit always start by running the drill backwards to scribe a nice clean circle that will prevent the surrounding wood from chipping out.  So far things are looking good.



But a few seconds after starting the drill in earnest we see that things did not go well.  Since the two halves of the fuselage are not yet glued together the two pieces slipped relative to one another causing an oval cut and the drill bit broke out of the bottom of the airframe. I was not a happy camper at this point and was not sure how to progress from here.



Here's what I did; just drilled a series of smaller holes in the area that will need to be hollowed out and then...



started digging out the unwanted volume with a chisel.  The pre-drilled holes sped the process up and helped guide me but overall this was pretty ugly work.



Eventually he chisels gave me a near semi-circular recess in each half of the fuselage that I could attack with a circular grinding tool.  



Fortunately at this start of this process I had intentionally left a few mm of surplus wood on the rear of the aircraft. When I sanded that off, the resulting hole was greatly tidied up. 



Of course once the tail was slotted into place the tail's root was still in the middle of the hole, so something had to be done.



After a couple of minutes with the scroll saw we had this...



Which after a bit of cleaning up with some rolled-up coarse sand-paper, left...



this!  Which I think looks OK despite the close call with disaster near the start of this post.  



Next up, the two halves of the rear fuselage will get glued together. Then I might start rounding off that very ugly square cross-section.


Sorry about the cruddy photos folks - definitely time for a new shed camera.


Best Regards,

Bandsaw Steve





  • Like 21
Link to comment
Share on other sites

Wondered where this build had got to @Bandsaw Steve, and it's good to catch up with your impressive progress.


There's been no doubt, for quite a while, what aircraft you're building and the end result promises to look great. Onward and upward !




PS any progress on Xantho ? 

  • Like 1
Link to comment
Share on other sites

Thanks mate. Pleased that you approve.


As for Xantho; for now no progress from my end. The ball is firmly in Ross Shardlow’s court at present as he continues to work on research. Once he has a set of completed plans they will go to the museum for approval and then building can start.


The project that is really stalled at the moment is the PZH 2000. I do keep planning  to get back to it, but this Mirage project is so enjoyable that it drags me away every time.

  • Like 1
Link to comment
Share on other sites

Gidday Steve, I have trouble concentrating on more than one thing at a time (typical male, I suppose) so I understand you focusing on just the Mirage at present. But I'm looking forward to when you get back to the others. Regards, Jeff.

  • Like 1
Link to comment
Share on other sites

I have just caught up this build. What you are doing here is amazing. Have you ever considered to machine the woods with CNC?

(maybe I am a bit CAD/CAM oriented. Therefore the only thing I can think how to machine the parts).

I will follow this build with great interest.



  • Thanks 1
Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
  • Create New...