Moon Bus RC Original Design not 2001

mung

Sr Member
Here is my next RC project, components of which have been kicking around for some time.
I'm calling it a Moon Bus.
It is in no way connected with the hovering vehicle from 2001 a Space Odyssey, this one has wheels and big tyres.

The design started with the tyres.

I had a set of Imex truck pull Clodbuster tyres sitting around for quite a few years, but have never had any rims to fit.
One of my random Ebay trawls came up with a really cool set of rims that would be perfect for these tyres and a sci-fi
flavoured project.

Below are the rough design thumbnails from my sketchbook.
I only ever do enough drawing to get the idea of where to start and the general direction to take, the rest is down to
actually building the main shapes, seeing and touching the volumes and improvising from there.

Top-012.jpg


The rims are an older version of the RC4WD Clod beadlocks which are no longer available.
I think you might still get a later revised version with a separate interchangeable hub.
These have a 14mm hex socket and came with some splined 14mm hexes designed to mate with the Tamiya Clod-Buster splined axles.
They are really beautifully machined and this set does not appear to have been used much, if at all.
The front beadlock rings have a number of cosmetic non-functional very short cap screws with 8 functional ones like the back rings.
The beadlocks actually completely seal the tyre so they remain effectively pumped up without any foams in place which is handy
given that the tyres didn't come with any foams.
They have sat around like this for several months now and still have not deflated.
They have a massive machined black anodised hub which screws in to hide the wheel nut and the rims are really thick and quite heavy.

P1011092.jpg



P1011091.jpg



P1011093.jpg


The two chassis plates I made from 3mm aluminium sheet, drawn up in Delta Cad, printed out, spray glued onto the
aluminium and all the inner corner radiuses were drilled out.
I then used a scroll saw to cut out all the holes finishing up with hand filing.
The blades for the scroll saw though designed for wood will cut thin aluminium but dont last as long.
I went through quite a few.
These were made way back in 2002.
The shape being inspired by the Tamiya TXT-1 monster truck.
I was planning to build a monster truck at the time but it never got very far.

P1011081.jpg


The chassis plates have been cut and shunted a bit.
Originally the idea for the monster truck was for the battery to sit low down on the extended sides, these have now been
chopped and moved to support the upper links.
The axles are once again a set from a Venom Creeper that have a manually switchable diff lock.
The transmission was originally from a Creeper, as shown in these early pictures, but that was put into the Toybash
truck project
and it has been replaced by an Axial SCX10 transmission which has a slipper clutch.
The lower links are Axial machined high clearance links just because they look cool and I already had a pair which I
got to try out on another project for which they didn't turn out to be suitable.

As usual it took a lot of fiddling to sort out the shock placement. They have ended up pretty much in the monster truck vertical position.
In fact this was the test bed where a lot of mechanical problems were tried out for the Toybash truck project.
The shocks are a set of Hot Racing oil-less ones that rely on air damping. They look cool but I am not all that convinced of their efficacy.
Once again they have to be able to push up the heavy body without it flopping over to one side that the usual angled
crawler shock position encourages.

The Creeper axles have a really annoying angled shock link mount so I had to make up a set of PVC adaptors so the shocks
could mount vertically without binding.
They are captured by some vinyl fuel tubing bushes which permit flexibility of movement.

The first set I made were straight but this meant the shocks were too tall so I made some curved versions.
The curved versions restricted the steering throw a bit and I did recently modify the mounts to cure this to be covered in the next post.

Thoughtfully a second hole was added in case there was a need for a sway bar set up.

P1011078.jpg


Above are the original straight mounts and below are the revised curved mounts.

P1011079.jpg



The other difficulty was getting those beadlocks to mount up. I needed some form of widener to get enough clearance
so the rims did not foul the knuckles and the links especially when turned.
I ended up getting some Integy 12mm to14mm hex adaptor wideners.
They came with two sets of barrel nuts, short and long. The long ones were not long enough.
Those beadlocks have about 10mm thick hubs whereas most plastic wheels have only about 3 or 4mm thickness.
The project ground to a halt for many months at this point while I contemplated what to do.
In the end I made my own barrel nuts from some 6mm bolts.
I got some 60mm in length M6 bolts and cut off the thread.
The remaining bolt shoulders were drilled out and tapped M4 to fit the axle thread and the beadlocks had to be drilled
out slightly to fit the 6mm bolts which are actually only 5.8mm in diameter. I have a set of metric drills that go from
1 to 5.9mm in 0.1mm steps, very useful for tapping and clearance hole sizes.

P1011197.jpg


I felt that the Integy wideners were too wide, if I could find something that has a much smaller offset and a 14mm hex I would swap them out.

It would also reduce the amount of tyre scrub when the steering is turned.
In an attempt to shorten the offset as much as possible I used machined down Axial narrow aluminium hexes designed for 1.9 sized wheels.

P1011082.jpg



A start was made on the body. A wooden frame has been cut and assembled.

P1011194.jpg



P1011198.jpg



P1011199.jpg



P1011203.jpg


The body is held on by 4 X M4 cap screws which pass through holes in the chassis and screw into threaded plates screwed to the wooden frame.

P1011206.jpg


All that work took place many months ago, more recent work described in a following post brings this project up to date.
 
Last edited:
A couple of issues which bugged me about this project have now been addressed.
The first was the fact that the Integy wheel wideners/adaptors made the wheels stick out too far.
I wondered if it was possible to find 14mm hex free machining rod and sure enough there was some on Ebay
so after obtaining a half meter length I set out to see if I could make my own 14mm hex hubs.
Below is the result. In fact this is a reject where I mistakenly made the slot for the axle pin 1mm too deep.

The slot was done using a 2mm milling cutter held in the mini lathe chuck with the hex gripped in the tool post packed
up to the correct center height using a 1.5mm scrap of aluminium sheet.
The hex adapter's hole was lined up with the center of the chuck using a lathe center.
The cross slide was moved 5.5mm out from center in both directions leaving an 11mm slot 2mm deep.

P1011525.jpg


The rims are then secured using the long barrel nuts from the Integy adapters which were originally too short.
I had previously drilled out the rims to fit my wider diameter home made barrel nuts so I had to make 4 brass tube sleeves
that fit over the Integy barrel nuts to fit the wider diameter holes in the rims.
The result is that the rims sit about 12mm closer to the axles and look and perform much better.

The other problem was that the location of the curved shock mounts on the axle that I made interfered with the full turn
of the steering.
That was fixed by shortening the fuel tubing bushes, swapping the cap screws to a lower profile button head type and
dremeling out a clearance groove for the shock shaft in the gray pvc mounts.
Now I get full lock without binding the ends of the steering servo travel.

P1011521.jpg



P1011524.jpg


The picture above also shows the newly made hex in position and the new more cosy clearance for the steering arm.

Added to the suspension set up was a front and rear sway bar.
A sway bar at both ends was possible on this project because I swapped out the Venom Creeper transmission (which went into the
ToyBash truck project
) for an Axial SCX10 transmission which locates the motor along side.
Again this has cured the heavy body flopping to one side problem as the addition of the single rear sway bar did in the Toybash truck.
You can clearly see the slot which allows the sway bar to slide back and forth as the suspension compresses.
The sway bars were made from bent 2mm piano wire.

P1011519.jpg


An electronics tray was made from 2mm styrene, heated and bent in the middle to match the angle of the side frames.
A flat raised section is added to support the battery and get over the top of the transmission which protrudes up through
a shaped hole in the tray.
A start has been made in laying out the electronics.
A small clamping antenna tube holder made from some 10mmm pvc has been added on one of the 6mm rod cross members.
There is a horizontal saw slot through which the m3 cap screw clamps down and a small vertical slot at the other end
which allows for the pre-housed antenna wire to pass through before pushing the tube into the 3mm hole.

P1011522.jpg



P1011520.jpg


A start has been made on skinning the wooden hull frame with 1mm styrene.
The wooden frame was sealed with shellac first which helps the thick super glue to go off quickly which is otherwise
a problem for porous plywood end grain.
I like shellac as it is easy to mix up the flakes with methylated spirits, it dries fast and is easily sandable, plus it is
a reasonably harmless natural material without lots of nasty chemicals of which there are more than enough in plastic
model making.

The areas of the plastic sheet that were to come into contact with the superglue were marked out and then roughed up
with very coarse sandpaper.
It took a bit of coaxing with clamps and tie down straps to get it to conform to the radius required.
It is impossible to handle when attempting to glue it all at once so I glued it in stages with the occasional assistance of that foul
smelling Zip Kicker (cyanoacrylate accelerant).
When doing this sort of thing it is wise to make the sheet bigger than needed all round and then trim the excess off
after the glue has fully set.

P1011516.jpg



P1011517.jpg


The interior of the cockpit has also been skinned. The circular side windows are made from a PVC pipe reducer.
It has a small lip on the inside against which an acrylic sheet disk window will sit.
A ring of pvc pipe that fits the inner diameter will then slide in from the outside securing the window neatly in place.
I plan to put a couple more porthole windows down the side.

The 1mm styrene sheet still has the clear plastic film protective sheet on it which is why it looks bit ragged in places.
I will leave that on as long as possible to stop the surface getting unduly scratched while I work on it.

P1011526.jpg



P1011527.jpg


The rear has a cut in half battery powered push light housing glued on.
There is a rear door structure still to be built and added in the gap as per the thumbnail sketch.

P1011528.jpg



P1011529.jpg


A 1/16 Bruder man squats in the approximate position he will occupy.
He originally had a co-driver to keep him company but he was requisitioned for the Toy bash truck.
I have a replacement coming and to mix it up a bit and redress the gender bias I am thinking it is going to be a Bruder female figure.

This project shares much in common with the ToyBash project having 4 wheel steering and sharing similar components in the drive train
They are also both in the same scale, the idea is that they would exist in the same world and time-frame.

More soon...
 
Last edited:
Soooo.... These smooth curves seem very "Gerry Anderson" / 2001 to me, and not as similar to the clunkier truck. Not saying one is better than the other, but is the moon bus going to be more on the smooth side or more on the chunky side?
 
is the moon bus going to be more on the smooth side or more on the chunky side?

This is definitely meant to be on the sleeker smoother side of the design scale.
The Toybash truck was supposed to be very mining/industrial in look and weathering.
The Moon Bus is going to be more Corporate in style.
Something for the "suits" to travel about in with a bit more space and comfort.

I have recently come up with a fictional purpose for the Toybash truck.
The idea is that it is a mobile power station comprising a very large capacity highly efficient battery that can be driven to remote outposts to provide temporary (several months) power for small bases and exploration teams.
It can also be connected to photo-voltaics for charging, extending its duration and power conditioning purposes.
A separate vehicle would transport the solar cell modules.

The Moon Bus can carry personnel and small cargo on long range trips to remote outposts.
It will have an array of photo-voltaics on the top of the hull plus long range communications equipment.
It is a more self sufficient vehicle which can also be used for rescue purposes.
In a squeeze it has life support to carry 10 though 4-6 personnel is more usual.
It is a little better appointed than the usual off world vehicles.

Thanks for looking,
mung.
 
The rear door structure has been built out of 2mm styrene.

The green bit is a piece of one of the rubbish truck toys from the Toybash truck project.

The light blue hand rails at the rear are heated and bent plastic knitting needles purchased cheaply from a Charity shop.
Knitting needles are a good source of solid plastic rod that can be bent without flattening out with a little heat and they
glue nicely with the usual solvent adhesive.


P1011541.jpg



P1011537.jpg


P1011536.jpg


You can see the under structure with a couple of holes that I covered up.
I was originally going with some round vents here but changed my mind.

P1011540.jpg


The communications dish sits in a well.
The circular shape surrounding the well is the outer dial from a washing machine made from good quality ABS.
The dish itself is made from another cut down battery powered push activated light.
There are two sizes of these, this being the smaller one, the larger is the one cut in half on each side of the rear hull.
These I find at the hardware store, the small ones come two to a pack and are much cheaper and more readily available
( to me at least) than equivalent EMA elliptical vessel heads.

P1011535.jpg


P1011539.jpg


The dish will be position-able but not motorised.


P1011534.jpg



The next task I started on was the side hatches.
I bought some dummy ccd camera housings for the clear plastic domes (for another project) on ebay.
The bases for the domes were cut down and employed for the hatch surrounds.
I needed a short tube to mate with the curved side of the hull.
After much thought and not finding any pvc tube the right size I came up with a fabricated solution.
I used this handy online tubing coping calculator to print out a paper pattern to cut some 1mm styrene sheet to the fish
mouthed intersecting shape fitting the hull curve.
You enter in the dimensions of the two intersecting tube sizes. the thickness of the cutting tube , in this case 1mm styrene
and the angle here being 90 degrees.
Basically I made two sine wave shapes which are each 180 degrees of the tube.
First I cut a circle of 2mm styrene 2mm under size in diameter and then placed a central former with the arc of the hull cutaway.
To this central spine I added various depth strips to match the curve.
Then this structure was wrapped with the 1mm styrene sine shapes.
A sheet of coarse sandpaper was then wrapped around the hull curve and the whole inner structure sanded to suit.
Although the black styrene makes it hard to see, it fits pretty well and only a tiny amount of filling will be required.

P1011532.jpg


P1011542.jpg


Once I had the surround sorted I drew up a suitable hatch shape in Draft Sight and printed it out full size.
All the corner radiuses get a centre mark.
This paper was glued with ordinary UHU stick glue onto two pieces of 2mm styrene stuck together with Scotch brand
double sided tape as I needed two of them, one for each side.
The center marks were first drilled out with a 2mm drill and then followed up by an 8mm step drill, all the rounded corners
having a 4mm radius.
Then I dug out the old scroll saw (the same one I used to make the aluminium chassis frames) and sawed between the
holes finishing up with some filing and then rounding the front surface edges by scraping with a 150mm (6") metal ruler.

side_door_cad.jpg



P1011531.jpg


A further charity shop find, a strange pleasant sounds maker designed to help people go to sleep, is going to be a
sensor dome on the hull at the front. This is just the top of it, the base having been removed.

P1011538.jpg


More soon...
 
Last edited:
I have added some lighting to the model. I purchased a 1m led strip light that runs on 12 volts.
You can cut the strip into any multiple of three of the surface mount leds and they will still work on 12 volts.

P1011577.jpg


The picture above shows what is left after cutting of all the bits I needed for the Moon Bus project.

P1011576.jpg


You cut the strip on the line between the 4 copper contact pads where it says +12V.
You then have to carefully cut away the clear covering over the contact pads and solder your wires to the pads.
It comes with a strip of foam tape adhered to the back of the strip so it can be stuck into position.
They really throw out an impressive amount of light.
For the front I added a length of the strip to a piece of aluminium angle.
A 2mm styrene box was then made to fit over this and secured with a styrene tab at one end and a dual ball cabinet catch at the other.
A small 3 led strip has been added to the cockpit interior as an overhead light.

P1011573.jpg




P1011571.jpg


P1011574.jpg


The rear lights were made from a two 3 led strips painted with Tamiya clear red.
A similar styrene box, made to secure in the same way as the front, hides the wiring connection at the rear.
Some kit part detailing has been added.
A single white led has been added to the rear porch to light the rear hatch.
A 1k resistor was calculated to be correct to run it from the 12volt lighting circuit using this online calculator
http://www.bennyinternational.com/lib/ledcalculator.html.

P1011568.jpg


P1011570.jpg


P1011575.jpg

To power the the lighting I will need a voltage booster to get 12 volts from the 7.2 volt motor battery.
The leds don't pull much current so I should be able to use a booster from Hobby King with no problems.

More soon...
 
The last entry on this project was December 2015, slightly more than 4 years ago.
I had some further technical difficulties with the vehicle's suspension but have recently come up with a solution which has cured the problem.

With renewed enthusiasm for this project I have selected it as the next one to see through to completion.

I have been working on the cockpit interior.

IMG_20200223_190405442.jpg


I had intended that a couple of 1/16 scale Bruder figures were to go in here but decided to swap them out for these Tamiya Tank crew which are to meant to be the same scale.
They were originally standing figures so it has taken quite a bit of butchery to get them seated.
They are quite a bit bulkier than the Bruder figures as well as being taller however they do seem to fit this space well and already look a bit Spaceman-ish with their soft helmets and headphones.

IMG_20200223_190602985.jpg


IMG_20200223_190627289.jpg


There is still a control console and a navigation console to be devised and fitted so its still very much a work in progress.

Thanks for looking.
More soon...
 
This thread is more than 3 years old.

Your message may be considered spam for the following reasons:

  1. This thread hasn't been active in some time. A new post in this thread might not contribute constructively to this discussion after so long.
If you wish to reply despite these issues, check the box below before replying.
Be aware that malicious compliance may result in more severe penalties.
Back
Top