Prototype Build Volume 2 Part 2 – Adding some colour

Over the last week we have been having a great time painting. We started with the fuselage, first taping off with masking tape all the surfaces that will receive the fuselage covering. Using a white universal water based undercoat we sprayed the wooden frame. It was my first attempt at spray painting anything bigger than a model and, having watched various videos on technique (thanks Youtube!) I started with trepidation. My fear was unfounded as with a reasonable amount of care the paint applied very nicely.

Universal undercoat applied

I have used the Tamiya XF71 as my cockpit green colour. It seems to be closest to what I could find on original paints. This being a Mk.IX Spitfire, the shade is a little darker than the early models. I was able to take a painted sample of wood to my local friendly paint merchant and after much trail and testing came up with an exact match. I now have the formula for achieving the correct shade in a water based PVA (Latex) paint.

Cockpit Green!

This paint was a little thicker than the undercoat but after thinning it with about 10 percent water it applied very nicely.

It is so nice the way the structure is now starting to look very much like the original

The painting has brought the sandwiched construction to its rights, the flat colour highlighting the details such as the lightening holes.

Structure coming into its own

Of course, I had to trial fit the throttle quadrant…

Spitfire Mk.IX Engine Hand Control

We have also had a go at painting the Nylon components. The XT3 Resin turned out to be unnecessary. It is very thick and in future I will rather use a normal fibreglass resin should I wish to get something really smooth. The XT3 tends to cover up important detailing. That said, I found that the uncoated SLS parts take paint beautifully without any further coating. I use Tamiya water based acrylic model paints and the colours lay on very nicely and smoothly with a brush. The following images give an idea. Lots of fun being had with this (and in between the creation of the sheet metal cutting patterns continues!

Compass

The instruments and the compass have had their decals applied but still need their clear plexiglass covers. In spite of not being finished, they are starting to look really good 🙂

Instruments with faceplate decals, glass still to follow
Morse Switchbox was not coated in order to preserve fine details. Looks great nevertheless!
Undercarriage Control Valve Block with one 1/4″ BSP hose fitting in place
Rudder Trim Wheel paint is complex but coming along

The Hood is Good!

I mentioned in an earlier post last week that we potentially had some good news on the Malcolm Hood. Typically these are made in the UK by specialist firms. A quote I received in July of last year amounted to GBP850 (US$1130). It was therefore important to find a means of making these considerably cheaper for our simulator.

The Malcolm Hood is just such an important part of the look of the Spitfire, we had to get it right.

The good news is that we have manufactured a batch of six of these locally. It still needs to be shown that we can manufacture them consistently with good quality. It remains more of an art than a science. If we can, we will be offering them at a significantly lower price point (read less than half).

We have manufactured ours from 3mm clear Plexiglass. This is the common thickness used for gliders and general aviation aircraft. The Spitfire typically uses 5mm but is subjected to considerably more force (500mph wind?!!) than our simulator!

I am therefore happy and proud to share a few pics of the hoods, including one which has been loosely placed on our prototype build. Looks rather handsome, methinks…..

Update to Terms and Conditions

As a result of a query we have received we have updated the Terms and Conditions which were perhaps a little onerous for our Throttle Quadrant.

It has always been our intention to allow the plans to be used for building a commercial simulator. Purchasing a plan set allows you to build one throttle quadrant (or simulator when those plans become available). You may use that simulator for commercial purposes, e.g. for a museum. (note however that as we have no control over build quality we cannot accept any liability for accidents or injuries that may occur as a result).

Another bit of news is that it is now only possible to log in to the site with your USERNAME (so please don’t use your email address, you will be locked out). This is as part of our ongoing security processes. If you have any problems logging in or other questions, please contact myself through use of the Contact Form.

Prototype Build Volume 2 Part 1 – SLS Nylon Components Received

We are entering the next phase of our build having received all 200 SLS Nylon 3D printed components. It is exciting and most gratifying to see how everything just works straight out of the box. Components clip together effortlessly and work beautifully.

Morse Code Signalling Box showing perfect fit of parts and fine detail

In this example we are displaying the Morse Code Signalling Box assembly. Internally the electronics components, in this case 3-way rocker switches, slide in and work beautifully. The custom recreations of the position switches clip perfectly onto the M2013 switches.

Morse Code Signalling Box internal view of the rocker switches

The SLS Nylon PA2200 is incredibly strong, having a tensile strength of 48MPA and it can take up to 163degC. You can find the full specifications here.

Our components have been printed in white, which will provide the best base for painting. The finish is slightly grainy and porous given the laser sintering technique. Hence we will be painting the objects with a resin base coating to give it a smooth finish. We will be trying out the XTC-3D product for this, which is readily available.

We will be coating our parts with XTC-3D to provide sealing and a smooth finish

Once the protype build is complete, we will be making all the components available through our shop on Shapeways.

We will be providing regular updates on the progress of the finishing and detailing of these parts. However the priority for now is to complete the DXF cutting patterns of the metalwork so that we can get those into manufacture. We have completed the 119 parts to be lasercut cut from 0.9mm aluminium sheet and have started on the 2mm sheet patterns. Only around 220 to go!

Numbering complete!

We have made steady progress over the last two weeks. The numbering, adding of metadata and checking of all components has been completed. This has allowed us to extract all the SLS Nylon 3D printed pieces and start generating the sheetmetal DXF files. We have also made good inroads into the development of a bespoke, low cost Malcolm Hood.

STL Files all generated

An STL file has been generated for each of the 200 SLS Nylon components. They have all been uploaded to Shapeways. These will be made available for purchase once the Prototype Build, Plans and Build Manual have been completed and proven correct and functional.

Generation of sheetmetal DXF files in progress

Our design contains 330 sheetmetal components as follows:

  • Aluminium Plate
    • 0.9mm – 119 pieces
    • 2.0mm – 134 pieces
    • 3.0mm – 14 pieces
    • 4.5mm – 44 pieces
  • Mild Steel Plate
    • 2.5mm – 19 pieces

A DXF cutting file is created for each of these components. The file is layered to allow engraving of the part number and bend lines prior to cutting. The images below illustrate this for component number 08-03-04-15:

Those components that require bending will also each have a bending diagram to provide guidance on the bend angle and direction.

Malcolm Hood Manufacture

Great news is that we have progressed significantly with the manufacture of a low cost Malcolm Hood. It will be made with 3mm Plexiglass. This is the standard for GA aircraft, hence should be suitable for use on a real aircraft. We have fabricated the necessary tooling and I hope to be able to report on further progress in my next post.

Malcolm Hood 3mm Plexiglass