Thursday, 31 January 2013

Stargate Kull Disruptor - Power Cell

Part 1 | Part 2 | Part 3

In the original prop this part holds an electronics board, that flashes lights when plugged in to the body. I spent a fair bit of time drawing up schematics in Eagle, intending to have some PCBs fabricated. However I came a bit unstuck trying to sort out the layout and ran out of time. I still want to output some PCBs from Eagle, maybe next time I'll try an easier circuit.

Power Cell

The tie-dye tanic power cell, as I'm calling it, is probably the trickiest part of this build. I think the original was milled out of brass, which makes replicating it, both the quality and finish, very difficult.

Regardless I ploughed ahead with cutting out plasticard.

After a lot of cutting, layering, filling and sanding I was left with these two. 
Not milled brass, but not bad either.

I've always wanted to try cold casting (adding metal powders to resin to achieve a realistic metal look). This isn't an ideal project for it. Cold casting is best done in larger open moulds on ornate looking pieces where you will get a good contrast when you polish it up.

This piece is small, in a two part mould and has lots of flat surfaces.

However I think they look pretty good.

There was a lot of experimenting to get these results. How much black pigment and brass powder to add can be tricky to balance. Then once the piece has cured I rubbed the pieces down with white spirit (this dissolves the surface of the resin allowing the brass powder to show through. Lastly I give them a final buffing with steel wool.

The paint job on these is odd, it looks like pink with splatters of brass showing through.
To try to replicate the look, firstly I splattered the pieces with liquid mask (a tinted latex paint that easily rubs off when dry)

After that dried I sprayed some translucent pink on them, then peeled off the liquid mask.

I'm sure it's not exactly how the original was made but I think it emulates the effect quite nicely.

Part 1 | Part 2 | Part 3

Cardboard Boba Bucket - Indentured

A slave to perfection. That's the problem with this build, the longer I spend on it, the more I want it to be right (definitely never redoing it).

Redoing The Dent

Originally Posted 26-Oct-2008 Very small update, I wasn't happy with my dent. It was too deep and lacking in detail. It's probably in the wrong place too but I can't be bothered moving it.

Any who I filled it up with polyfiller and sketched a design onto it with pencil. I over exaggerated the shape because I knew I would loose some detail when sanding. 

Then using a small half round file I began to etch out the main lines.

After that I filed out the main, depressed areas.

Then with the file I began to round off the raised areas. After that I moved to sandpaper and ended up with this.

Not perfect. But I think it's better than before What does everyone else think?

CNC Mill Build - Belting Along

The Z Axis I finished up last time now gets fitted to the front of the X carriage.

The Makerslide is slide between the V wheels attached to the front of the X carriage, and the black delrin nut is bolted in place.

The final task is to attach the pulleys and belts.

The red aluminium blocks are belt tensioners. By turning the bolt you can easy tune how tight your belts are.

That completes the physical build, or at least I've run out of kit parts.

The next thing to do will be to hook up some electronics and see if I can get it moving.

Stargate Kull Disruptor - Intro

Part 1 | Part 2 | Part 3

Another prop build, this time from Stargate SG-1.

This project arose from theRPF's annual secret santa gift exchange.
Upon finding out that my recipient also liked Stargate I started researching some props, obviously there are a lot of Zat's and other Jaffa costume pieces. But I wanted something that hadn't been done to death and that would be relatively simple. 

That's when I stumbled upon the Kull Disruptor.

Stargate SG-1 8x06 'Avatar'

It's a neat little attachment that clips onto the teams' weapons. Developed by the SGC to take down Anubis' Kull Warriors, it features heavily in the episode 'Avatar' (8x06) but pops up elsewhere too.

It's nice and small, recognisable from Stargate, (even if you don't know exactly what it is) and I reckoned it should be simple enough :s .

Scratch Build

Firstly I set about drawing up some good schematics to work from.

Then I just printed out some templates and began to cut pieces out of plasticard, with a scalpel.

These are all cut from 1mm plastic, fairly easy, if a bit tedious.
These plastic pieces fit together to form a cross section of the piece. 
It was filled with Bondo to give it mass and then the shape was rounded out with various files and sanding sticks.

The final step was carving the lines into it with a Dremel.

Unfortunately I seem to have forgotten to take pictures during most of the build up of this piece. However you can still see the remnants of the plasticard in there.

The back part is flat to accommodate the power cell and magazine.
The building of which will be in the next post.

Part 1 | Part 2 | Part 3

Wednesday, 30 January 2013

CNC Mill Build - Zzzzz

I am slightly regretting this procedural format I've locked myself into now, but I'd better finish it . 
In the previous post I bolted together the X and Y carriages to form the main framework of the machine. Now I'm tackling the Z axis.

The Z axis is different in that it is screw, rather than belt, driven.

The flexible coupler and flanged bearing are attached to a length of M8 threaded rod. The aluminium tape is wrapped round the rod to ensure a tight fit.

The threaded rod is coupled to the final motor and the bearing is sandwiched between the two Z plates.

The black brick is a delrin nut, it is threaded onto the screw and the final length of Makerslide is bolted on.

These are the spindle mounts, once the machine is finished they will hold the Dremel.

That finishes up the Z axis. Now all I have to do is mount it to the machine, 
and add the belts,
and sort the electronics...

CNC Mill Build - Squaring Up

Starting with the two Y motor plates I'm going to build the gantry for the X carriage I built last time.

These are the two X lengths of Makerslide as well as the belt anchors and a belt and pulley.  (I'm going to wait until the end to mount the belts.

The X carriage is now mounted between the two Y plates, completing the Y carriage.

Two more (longer) lengths of Makerslide and the two endplates.

I now have the basis of the machine assembled :D

The mechanics of this bolt together nice and easily, I'm less certain about the electronics :s

Next up is making the Z axis.

Cardboard Boba Bucket - Venti

Something about a bucket of coffee? I dunno,  I'm redefining tenuous puns.

Anyway this time I'm constructing the vent.

The Vent

Originally Posted 04-Oct-2008
Tiny update, I still have none of the proper materials at my new house but decided I wanted to carry on anyway.

With no printer I had to construct the keyslot pieces using a pencil, ruler and set-square. It took forever.

After that It took me ages cutting out the delicate vent piece. Going over each line several times very gently.

Its worth doing this slowly to get those sharp, square edges.

These are all the pieces necessary, the frame has an extra bit of trim so it will attach to the rest of the helmet.

Unlike the rest of the build for this I had to use Uhu glue. It left the piece a bit scrappy, not generally how I like to do things. Hopefully with a bit more work I can tidy it up.

Note: remember when wetting and bending the vent, the good (best looking) side should be the inside curve.

That's all for now

CNC Mill Build - X Carriage

This is continuing fromt he last post where I was assembling one of the Y plates.
This time I'm going to put together the X carriage.

X Plate (all plates are identical)
Motor, smooth idlers and fixings.

This starts off similarly to the Y plates, except that here the motor is mounted flush against the plate.

The two X plates get bolted together to create a nice solid box, here you can see what's going on inside (that shot was a lot harder to take than it looks, because nothing is fixed)

The last X plate finishes off the carriage, but in this step the V wheels for the Z axis are also added.

Next I'm going to bolt the motor carriages together to form the basis of the machine. : )

Once it's all squared up you get a much better idea of how the machine is going to work.

Sunday, 27 January 2013

Cardboard Boba Bucket - Dome Wax

The following is a documentation of the hours I spent at uni polishing my helmet. 
Note: May be unsuitable for minors.

Finishing the Dome

Originally Posted 28-Aug-2008
This part wasn't following Antman's tutorial, because he hadn't posted that stage yet.

Still it was fairly simple,  get out my pot of dodgey polyfiller and cover the dome in it.

You may also notice I've painted some of the edges, this was just to stop them from being damaged too much during the next stage.

I was fairly happy with the finish on the cheeks and didn't see the need to cover them in polyfiller.

Next ( after hours of sanding )  The dent.

Originally Posted 22-Sep-2008
Right, only a little bit of progress. I bought some Tesco value sandpaper for about 50p. Then started sanding away at the mass of polyfiller. Working down from 60grad to 100. I wrapped the sanding paper round a block of wood to try and get better control.

After a lot of sanding here it is.

I also started on the dent, This is where accuracy went out the window. I cut a random sized hole in roughly the right position. Glued a bit of card behind and filled it in with polyfiller (had to do this in layers)

I then made the main lines using a small file. After that I've been slowly shaping it with 60 grad sandpaper.

That's all for now I need to finish the dent and then when I get some supplies I'll work on the vent.

Note: these are now camera phone images as the camera I used previously wasn't mine and I couldn't bring to Uni.

Total spend is now £5.50. 

 Large card for main helmet & mask : £2.00
 Pint o' PVA Glue: £3.00
 Sandpaper: £0.50

Originally Posted 23-Aug-2008

This was taken with the webcam on my laptop, hopefully its a bit better.

Saturday, 26 January 2013

CNC Mill Build - Just Like Lego

Last gime I gave a bit more info on how I got interested in CNC and where this kit came from. Now I'm actually putting it all together.

Everything in this kit was so beautifully packaged and labelled it reminded me of cracking open a fresh Lego kit. The sheer delight of all the tiny bags of sorted pieces brought back many a childhood memory.

Anyway all this organisation prompted me to tackle the build in a very measured and precise way, not at all how I usually work.

So for each step, I laid out all the parts and took a picture. 
The first step is bolting one of the Y motors to a motor plate.

Bolt on 2 smooth idler wheels. These just guide the timing belt in the right direction.

Bolt on 4 V-wheels. These are what will actually grip the Makersilde rail. 
Those two small parts in the bottom left are eccentric spacers, they're slightly offset so that you can adjust how tightly the wheels grip the rail. It's this kind of simple problem solving, that makes this design so good.

That's one of the Y drive plates finished (the other is simply a mirror image).

Next time I'll be assembling the X carriage.

CNC Mill Build - Intro

Ever since I found out about computer controlled production, I've wanted one of the machines for myself. 

Start up projects like the MakerBot (my first love) have made it much easier for anyone to get into digital production. But The $1000 price tag was still far too much for me seeing as I was still a student.

Image credit:

During my time at uni I had access to a laser cutter, which was great, but limited to 2D production, and I used the Shapeways service to get a few 3D models printed. But found the price tag prohibitive and the 2 weeks of waiting between design and product was painful, and ruined one of the fundamental principles of digital production*.

But in my third year of uni I got it into my head that I was going to build a CNC mill. 
I did a lot of research and made a bill of materials. My aim was to build the whole thing for under £200. Long story short, I got the mechanics working (sort of) then ran out of steam.
The beast is currently disassembled in a box and may be worth it's own (rather depressing) post, it just wasn't going to be accurate enough for me.

Jump to October 2012 and for the first time in a long time I have a job and then stumble upon project Shapeoko. An open source kit that aimed to get you up and running for $300.

And just when I started looking at how I would get all the parts in the U.K I found the eShapeoko! Someone in Europe was selling kits, so almost immediately I ordered one.

Because the project was new they were still having problems sourcing all the parts but finally in mid January this rather small, but tantalisingly heavy package arrived at the door.

eShapeoko #23

Individually labelled parts bags. Almost more exciting than the actual machine.

Here's everything that came with the kit. Lots of lasercut steel, several lengths of Makerslide (more on that later) and various other bits of hardware.

I wanted to paint my kit to protect it, but mostly so it would look cool. I had a lot of black spray paint, and only a bit of red (left over from my Red Dwarf phone). I think that dyeing all the nylon spacers may have been a step too far, but I guess I was just over excited.

I may never get it running, but it's damn well going to look sexy!

The only other bit of prep is tapping the ends of the Makerslide. 

Makerslide is a new bit of hardware that was originally a kick-starter project by Bart Dring. It's similar to a standard aluminium extrusion, used in many designs that need to be strong light and inflexible. The key difference is that Makerslide has a set of V rails on it, which allows it to be used as the primary linear motion system as well as the main structural support which makes it ideal for small (or quite large) machines that need linear motion.

Well the colour scheme's all done, now I suppose I actually have to put it together. 

In my next post I begin assembling the kit.

* I think the direct link between designing on a computer and then very quickly being able to hold it in your hand, assess it and make changes is one of the best things about this technology.
However I still think Shapeways is a great service and I've always been really happy with their parts. It's still probably the best way to for newcomers to experience digital production without having to spend hundreds on getting set up. As well as the fact that the machines they use are far better than any home setup and give the option of printing in all sorts of cool materials.