Moon Bug Part 7 completed.

 Note: Google informed me today that they deleted my original "Moon Bug part 7 completed" post as it didn't meet their guidelines, something about malware and viruses. I have no idea what they are talking about and there seems to be no way to ask exactly what was the problem. If there was any malware or a virus it certainly wasn't put there by me. I find it really irritating that without any warning they just delete something that I put a lot of effort into and then don't have a mechanism for any helpful discussion. How am I supposed to prevent this happening again if I have no understanding of why it happened in the first place?

So now I have to re-create the post, luckily I also post on the RPF so I have a record of the original text.

Last time the model was at the primer stage, so the first job was to devise a paint scheme. As is my process these days I took a grey primer photo into photoshop and fiddled about until I came up with something I liked. As the vehicle has a whimsical comic book outline I wanted to do a colorful paint job to go with it. This is what I came up with.

I then decided to design up and make some decals to add to the graphic nature of the finish. These I designed in Inkscape which is a free open source vector graphic editing program. I have always liked the graphic elements that Chriss Foss would apply to his gouache painted spacecraft book covers of the 1970s'. Referring to my Chriss Foss art book I availed myself of some of his genius and some of the decals do bear a very strong resemblance to his work. Here is the decal sheet.

One of the problems with DIY decals is that inkjet printers can't print white so if you want white in your decal you have to use white decal paper. That then means the carrier is white and you have to carefully cut around each decal to remove the extraneous white around the edges. Of course you can use clear decal paper which means you don't have to be as precise when cutting out the decal as the borders will be clear and will not be visible once applied but any white areas on your design will come out clear. If it is a big decal you can paint a white area where you want the white bit to be but for small decals I think it would be too hard to get the white painted areas that accurate.

I printed onto white decal paper and once cutting out the decals and applying them with much setting solution found that little white edges showed up which wasn't exactly what I wanted. I have since found some online tips for using white decal paper, where the edges of the decal should be coloured with a permanent marker to get rid of any white bleed once applied. Too late for me but a good idea for any future project that needs custom decals.

Paint was car paint from touch up spray cans with varying shades mixed up once decanted into airbrush jars and airbrushed on. Weathering was my usual method of a wash of Tamiya flat back diluted in much methylated spirits, wiped off with a metho soaked rag in the direction of the required streaks and drybrushing with white students acrylic. I then also added some oil paint colour modulation and a dirty brown pin wash.

One of the things I tried out on this model was painted panels lined out with a fine permanent marker pen. Models from Terrahawks recently came up for auction with accompanying photos and they had a surface that used a similar technique to very good effect.

My conclusion is that I prefer to have panels that are in the very least scribed into the surface if not actually separate from the underlying surface and glued on individually. I prefer the way light hits an actual edge with both a highlight on one side and a shadow on the other.

One thing I added to the model was a couple of dummy whip aerials on the top blisters at the rear. They are made from bicycle gear cable with a couple of plastic kits parts for a mount and a termination at the top. They should wave about fairly realistically when the vehicle is in motion.

Finally here is the finished model.

 

Thanks for looking...

More soon...

 

Moon Bug part 2

I have been progressing on with the glass house cabin.
It has been fiddly to get the side mullions straight as they have to be curved to fit the curved bowl and end up looking straight.
The method to achieve this is to place some masking tape on the curved surface and then draw a line outlining the shape you want. When you peel of the tape and place it on some flat sheet you will hopefully have all the curvature in the right place so that it becomes straight again once cut out and glued back onto the curved surface.
The 2mm thick styrene has to be massaged into the required curve by hand first before cementing into position.
The other thing is to try and not get any cement onto the clear glass areas and fog them up. If any small bits of solvent do mar the clear areas you can usually polish it out with a plastic polishing compound.

 
All the power supply wiring has been installed and tested. I have a ubec providing 12 volts from the 14.4 volts delivered from two 7.2 volt Lipo batteries in series which power the vehicle.  12 volts is being provided to the cabin lighting and the two 10mm led tail lights which each have the required resistor to work with 12 volts. The head lights are two cheap LED torches which are supposed to run on 4.5 volts from three 1.5 volt dry cells. I found a small cheap DC to DC converter board which has an adjustable output voltage so I am down converting the 12 volt supply and providing 4 volts to run the headlights. I found the torches started to draw a lot more current at 4.5 volts so I dropped it to 4 volts which was about half the current and more or less the same brightness. Getting the torches to work took some fiddling about until I found the DC to DC down converter board and I burnt out a couple of torches in my attempts. Luckily they only cost a couple of dollars.

The is a tiny board stuck to the top of the UBEC in the picture below is a Pololu rc switch with small low side mosfet. It takes a signal from the third channel on the transmitter and switches the lighting on and off remotely. I believe you can find a similar thing on HobbyKing.com already wired up.

 

10mm Led tail Lights

Converter board providing 4 volts to the headlights.

 

I am using twin old school brushed motors in this vehicle which are more than capable of pushing this heavy beast around at a decent if not frightening speed given that this is a heavy custom made one off body shell. The electronic speed controller is a Hobbywing Quicrun WP 880 for dual brushed motors. This setup is also I might add considerably cheaper than a brushless system.

Thanks for looking.

More soon...

Mad Space Crusher AKA Moon Bug part 1

Winter has set in here and its too wet to paint the Moon Bus and the charity stores have re-opened so I paid them a visit. I found some more acrylic wine glasses which will be good for the engine bells for a future project and I came a cross a large acrylic pot that I thought might be useful for a rainy day.
It so happened that a rainy day did come (I've already explained its winter) and I had an idea of what to do with this  shape. Once I get an idea everything else is instantly dropped and I feel compelled to follow it up. This is what I call the experimental phase of a project. I'm trying to see whether an idea has legs or wheels in this case. Sometimes the this phase comes to nothing, things don't work out as hoped and the idea is dropped and it never becomes a fully fledged and documented project.

After a rough thumbnail on some scrap paper at work while waiting for a CNC cycle to finish I came up with this tiny germ of an idea for an RC chassis I have on hand.

Initial rough thumbnail.

I had a scrounge through my boxes of shapes and came up with a the dome from a Crayola colour explosion toy. This is the third one of these I have picked up from charity shops. It had a matching diameter to the big acrylic pot. I also found a small acrylic bowl which matched the other end of the pot. A few days later I did some more thumbnails with the found shapes in mind.

About a year ago I picked up a chassis of a Kyosho Mad Crusher because it was relatively cheap and I always liked the big solid axles of that particular design. this old chassis design has been updated over the years and it now has a 5 link suspension system. The chassis I got didn't have any tyres or wheels or electronics but I had some Imex Jumbo max tyres and wheels from an abandoned project sitting in a box which I figured would fit the bill.

It turned out the old 14mm hex wheels didn't fit and fouled the axles even with the correct Kyosho 14mm adapters. So I had to find a set of Hobao 17mm monster pirate wheels which have been discontinued. Lucky for me I think I may have picked up one of the last remaining sets from Taiwan where they were originally made and they fitted perfectly.
The chassis has been sitting around for about a year and I did a number of designs for it but none of them got past the initial idea.

The big acrylic pot find was the catalyst to kick this project into go.

The Mad crusher is pretty wide especially with the wide wheels and tyres I have on it, so the body needs to be wide to suit. The first thing to do was to cut the shapes in half accurately. I marked out the centre line with masking tape and carefully cut along the edge with a zona saw. I bit of sanding on a flat sanding board and the edge is ready to be glued with methylene chloride to the  flat 2mm styrene sides of the centre section of the hull.
The bottom of the pot was about 10mm thick so I chain drilled it out and cleaned it up on the belt sander.  Chain drilling is where you drill a series of holes closely spaced and then follow up with a larger size drill which hopefully breaks through the web between each hole thus freeing the section you want to cut out. Removing the thick portion at the bottom was a vain attempt to reduce some weight of the body always necessary using an off the shelf RC vehicle which is only designed to hold up a lightweight Lexan shell.

acrylic pot cut in half.

Removing the thick bottom by chain drilling.

All the acrylic to styrene joints were reinforced with some baking soda ( sodium bicarbonate) and thin superglue.

 All the styrene joints were reinforced with a narrow strip or doubler.

I made some grills or vents to go inside the little acrylic bowl from 1mm styrene strips sandwiched together with a small evergreen strip spacer between the strips.

 Here is the rear section on the just sitting on the chassis.

I took this photo into photoshop to try and come up with a cabin section but didn't have any inspiration so I went back to the shapes box for a further rummage. I tried out a few things, one of which was a hamster ball but ended up with another couple of small acrylic bowls and decided that arranging them in Princess Leia hairstyle like arrangement was the go. A couple of Bruder figures at 1/16 scale are placed in their eventual location in the cab. As seems to be my custom there is a central access to the rear of the vehicle. Here I would usually put a door but decided in this case on steps down to a short hallway behind which I will put a baffle or wall that suggests you can go either left or right just to add a bit more interest.

The last photo I took into photoshop to try out some glazing ideas. I settled on a relatively simple glasshouse idea shown below.

On the model I have added a couple of recesses underneath at the front for some LED torch headlights and am starting to work on the curved glass house. I plan to use some thin sheet lexan for this if I can get it to curve without springing back. I want to be able to remove the front glass while for access to detailing and eventually painting the cabin.

Thanks for looking.

More soon.