AI Desert Racer RC Vehicle part 3

Once the 3D printed main hull was completed it was time to go old school and fill in the undersides with kit-bashed detail. In the picture below is a few parts from a Wall-E truck toy, a Bruder dozer toy and a bunch of bits of old transformer toys. Mixed in is a few plastic kit parts and some garden hose fittings.

The large black rear exhausts are the bass reflex ports from a Sony mini hifi, the same one as is being used as the front of this unfinished spaceship project, Sony Spaceship Two

This was all adhered to a 3mm sheet of foamed PVC. Once all the nurnies were in place I cut the excess pvc backing away at the bottom right up to the edge of the detail.

The rear detail block is mostly made from a couple of Duplo blocks with the requisite kit part details added.

After priming with grey primer I then added a lot of pipes made from some single solid copper core insulated wire and some thicker black multi strand electrical wire. This type of wire can be bent and stay bent due to the solid core. One problem with this insulated wire is that some types of grey primer remains sticky once painted, I think due to the plasticiser in the insulating PVC sheath. I have tried dusting it with talc which removes some of the stickiness. I think it is fine if painted with water based acrylic hobby paints.

 

Just visible below is a large thick pipe/hose made from solid foamed neoprene rubber.

Nurnies were added to the top surface as well.

Finally all the detail including the pipes received a final coat of grey primer.

It was then time to add the final colours. In this case I used Montana MTN94 spray cans, a grey, two shades of  off white and an orangy-red. I am big convert to the MTN paint. It is designed as grafiti paint but is perfect for these large models. It is a matte finish not affected by the oil wash weathering process and sprays really nicely with excellent cover. It also doesn't smell so bad and is available in 200 colours.

You can see in the picture below I added a couple of headlights (a last minute addition) to the nose. I carefully drilled through the 3D print and added a couple of 12 volt "eagle-eye" cob leds. At this point hey have the lens covered in masking tape.

After the paint had cured for a week I started on the vinyl cut graphics. Using Inkscape, the free open source graphics editor, I made copies of the vague AI graphics depicted in the AI artwork. These were then cut from the appropriately coloured self adhesive vinyl on my Silhouette Portrait 3 cutting machine.

The cut graphics were weeded of the unused bits of vinyl just leaving the symbols on the backing paper. I just used a low tack masking tape as a transfer tape to apply the graphics in the right spot on the model.

A few random rectangles of vinyl were also added here and there.

Next up is the last phase of the build - weathering.

Thanks for looking.

More soon...

Watchtower part 1

 I have always wanted to make a shallow dome roofed watchtower of some sort and over the years scribbled many thumbnails of the sort of thing I had in mind. Until now I had never found a suitable large shallow dome... then one suddenly appeared ouit of the blue, part of a microphone shield that had been removed at work.

The thick acrylic blow moulded shallow dome with a diameter of  695mm ( 27") was perfect for the roof of a 1/16 scale structure. The first thing I did was to scribble up a new sketch of the general arrangement.

I trawled through my hoard of scrap materials and dug out anything that looked like it could contrubute to the project. 

The picture below is shows the general layout as it stands.

The main support column comprises 150mm PVC pipe with a 150 to 100mm reducer. This then joins to a black part from a broken water pump. The watre pump part then joins to a plastic salad bowl on top of which is a plywood disc that has a bunch of custom 3D printed parts, another plywood ring with a window made from thin polycarbonate (lexan) window. The dome then sits on top of that.

The 3D printed circular segments were designed in Onshape and then printed out at home on my Anycubic Kobra Neo FDM printer and a few at work on a Prusa MkIV. The Prusa prints were faster and slightly smoother. This is not surprising as the Prusa cost 6 times the cost of the Anycubic machine.

Anycubic Kobra Neo print on the left, Prusa MkIV on the right.

Close view of the Anycubic Kobra Neo print.

Close vie of the Prusa MKIV print.

The printed parts were superglued to the underside of the plywood ring with a 3mm black foamed PVC sheet spacer inbetween. The white wall that seperates the plywood ring from the plywood disc floor is also made from 3mm foamed PVC sheet in this case white.

On top of the plywood disc (or in actuallity underneath) was glued the palstic salad bowl with a amller plywood disc acting as a locator and re-inforcing the glue joint. The salad bpwl had the bottom cut off and ws securely superglued with baking soda re-inforcement before attaching to the plywood.

More 3D printed parts were arranged radially around the salad bowl and superglued.

The water pump part has a threaded end with a locking ring. I decided this could be usefull to seperate the column for tranport. A piece of solid PVC sheet was cut to fit inside the locking ring and glued and screwed to the top of the PVC reducer. It acts a lip to so I can easily lock the bottom part of the column to the top and  seperate the two parts when required.

In the picture above you can see I have started to add detail to the pump part of the column. The pump hosing had a cast aluminium heatsink to which I added a perspex plate using the existing threaded holes. To the acrylic plate I have added atank made from  part from a commercial toilet roll holder with a coffee machine spout part glued to the top. Detailing has also started on the PVC reducer.

To the bottom of the column I added a short scrap of 200mm gas pipe to give it a wider stance and better stability. Some detail parts have been added, with a lot of pipes made from heat bent solid ABS rod.

The chunky pipes shown above are from a childrens toy which is basically a pipe assembly kit.

The next design task was for a 3D printed door. Again modelled in Onshape and printed on the Anycubic Kobra Neo. 

The figure in the doorway is a 1/16 scale Bruder toy man. A large hole was cut into the base of the PVC column to fit the door.

I made a slight modification for an interior door inside the wathtower itself at the top of the column. It has to fit a smaller diameter PVC tube and has a flat base rather than the round base of the exterior door.

On top of the dome I mounted a motorised communications dish which I have had sitting around for at least a decade for just this project. The dish sits on a planetary drive gearbox and motor that rotates it at slowish speed.

The height of the model to the top of the comms dish is currently sitting at 1325mm (52").

Thanks for looking.

More soon...

AI Desert Racer RC vehicle part 2

 After layers of spray putty, primer, spot putty and sanding I finally got a reasonably smooth 3D printed body with almost no layer lines visible. Then it was time to fit out the cockpit.

The front suspension shock absorbers intruded into the cockpit area a bit so the seating and indeed the backs of the Tamiya 1/12 scale Formula One driver figures had to be relieved for clearance. The seating was made from 3mm foamed pvc heat bent into an S shape to fit the driver figures. 

Once that issue was sorted I could begin adding kit part detail to flesh out the interior. 

The figures required some modification to get their hands into position and the steering wheel was made from a piece of 2mm styrene, filed to shape.

The exterior body work was scribed into panels using an OLFA plastics cutter and was followed with a coat of grey primer for both the interior and exterior of the vehicle.

Thanks for looking.

More soon...