May 172012
 

Not my normal geek type post today, but still very geeky. This weekend I was at a science fiction convention at the Renaissance Hotel in Heathrow called Inva2ion. One word sums up the weekend for me:

EPIC!

This was my fourth convention ever, and they just keep getting better. They are run by a guy called Sean Harry, and his company StarFury Conventions, and they are just the perfect mix of sci-fi geekery, and all night partying. These are not like your Comic-Con type events you may see on TV shows or the news when people talk about conventions, they are much smaller affairs with a much more relaxed atmosphere. There are usually a good selection of guests doing talks through the weekend, and quite often they will join you for a good party each evening. All the attendees are fantastic as well, you couldn’t hope to meet a better group of people.

Now this weekend started off well and kept on getting better. As soon as I arrived at the hotel with my good friend Mandy, and had checked in, we went down to the lobby to see who was about. As well as some of the usual convention regulars, Aaron Douglas (The chief, from Battlestar Galactica) was having a few drinks with some of the attendees. It turns out he had got there a day earlier (and so had some of the attendees) and was actually staying in the same hotel. Most other guests get put in a different hotel so they can escape the fans if they want to. Not the chief! He was here to do some serious partying! So, the weekend started simply sat round the bar chatting with someone I’d been watching on TV just the day before.

You find some of the guests really do embrace the fans and enjoy themselves at these conventions, and to be sat in the bar whilst Aaron is tweeting pictures of gifts he’d been given, and telling Wil Wheaton that his fans are so much better, shows how fun these events are.

The Saturday and Sunday daytimes are taken up with guest talks which are almost always highly entertaining. Each guest has so many fantastic stories to tell and the fans have the chance to ask what they want. This weekend was no exception. Aaron kept the audience in stitches telling us about meeting Robin Williams, who turns out to be a big BSG fan, and also not recognising Joss Whedon whilst talking to him at a bar (almost a capital sin with some of the convention goers). Alessandra Torresani (The original Cylon from Caprica) was her usual bubbly self, and managed to get a few stories in, even though she shared the stage with Aaron. The girls from Stargate: Universe (Elyse Levesque, Alaina Huffman) were rather fun and told some good stories about behind the scenes, and also gave us a rather crude rap! The Guild girls (Amy Okuda and Robin Thorsen) were all lovely, with Felicia Day taking center stage as the Queen of the Geeks. Eliza Dushku seemed to be the guest that a lot of attendees had been waiting to see at a convention for a long time, and shared the stage with Dichen Lachman (Sierra from Dollhouse). The only guest that I didn’t see was one of the convention regulars, Jim Swallow, who is someone whos work you will probably have seen, but not realised. He is a writer for many sci-fi shows, including Star Trek, and had a lot of support and advice for potential writers.

Now, these were all the talks on Saturday. I only made it to one talk on the Sunday, and that involved a couple of rather hung over Cylons, and the Rev Johnny Woodward, and communion. Now communion at a convention is a sight you have to see to believe. After an hour or so of hungover (or maybe still drunk) ramblings on stage by Jonathan, Aaron, and Alessandra, a large portion of the attendees line up and pass infront of the stage. As they do, they get given a biscuit (or in this weekends case, a pringle) and then proceed to get whiskey poured down their necks (and wiped on their faces). From my understanding, this started many years ago and has become a firm convention tradition, and even if Jonathan isn’t an invited guest to a convention, he will still on occasion turn up for the party and to hold communion, even more so now he actually lives in the UK.

I didn’t make it to any of the other talks on Sunday as an old friend was in the area and popped by to see me.

As well as the talks, you also get chance to get photos taken with the guests, and items signed. I’ve never bothered partaking in this side of the convention, but may do in the future. Most of the guests are up for fun photo shoots too, with some people being rather creative in their ideas. I believe one guy turned up with a traffic cone!

Thats all the main geekiness covered, apart from the parties! Each night is a disco with a fancy dress theme, and the costumes never disappoint. Some of the attendees go all out on their costumes, and this time was no exception. Of my favourites this weekend were the steampunk Lord of the Rings group entry, and someone going as the adventurer from the old kids TV show, Knightmare. The disco is usually a good mix of music and there will be something for everyone during the night, but what has to be seen to be believed are the con dances. Over the years certain songs have been choreographed and all the regular attendees know them well. Its quite a sight to behold the whole dancefloor moving in unison, and as for Star Trekking, well… My hat is off to Aaron, Dichen, and Robin for being some of the last standing. Dichen was still bouncing all over the place at the end of the night. Too much energy! The parties carry on long after the disco has stopped and we have been thrown out of the main hall. The lobby of the hotel gets taken over and the drinking and fun carry on until the early hours. Some people infact stay up long enough to get breakfast before going to bed.

Of course, all this would be a fun weekend in itself, but what made the convention for me were the other attendees. Now, I’m not exactly a confident person when it comes to talking with people. If I’m approached, thats fine, but I can rarely go up to people to strike up a conversation. This weekend was different. I’ve started to get to know a lot of the convention regulars over the last few events, and this was the first time I actually felt like part of the convention family. I was totally at ease, and managed to get to talk to quite a few people that I’d seen from previous events but had felt uneasy in doing. Whats more, they all made me feel accepted. Monday evening was a flurry of facebook activity as I added a lot of new people. If any of you are actually reading this, you guys are just awesome!

So, I’m booked on the Vampire Ball in September, and I’m seriously considering going to the 11th Hour in Birmingham.

Back to the reality of work tomorrow, and off to the States on Sunday!

Oh, and go check out Geek and Sundry!

May 012012
 

Another success. The Reprap prints!

Prusa build

The hotend was the last piece of the puzzle. I managed to get the new one built, installed and extruding well thankfully. Next came trying to get a decent print out of it, but this is easier said than done. Calibration of the Z axis is very tricky with very little room for tolerance, especially if you haven’t got a heated bed. Getting the first layer to stick is a case of having the nozzle extremely close to the bed of the printer, so much so that it extrudes and forces the plastic into the bed. I managed to get the two objects off pictured above and the quality is rather good for a first attempt. Still, there is a lot of room for improvement. The X axis needed a lot of tightening up (my first print was actually a belt tensioner), but that was easily accomplished with zip ties to tighten the grip of the carriage with the bearings on the smooth rod.

Next step was to get the heated bed working. After some talk on the forums, it was suggested by a guy called nophead to replace the standard MOSFET with one better suited. After ordering one from RS and replacing it, the heated bed worked without melting the electronics, just. It was still getting very hot, and still needs either a cooling fan or a heatsink. In the process of swapping the MOSFETS I’ve made a bit of a mess of the circuit board, with some of the tracks lifting off and breaking. Some hasty cludge repairs were needed and the bottom of the board looks a bit of a mess, but at least it works. With the heated bed working and running at 100 degrees, laying down the first layer has become a lot easier. The first layer finish is a lot better too, a nice shiny flat surface. I did have to print out some corner supports for the heated bed to try and cut down on the vibrations due to the bed wobbling. The other benefit of a heated bed is that it stops warping. I tried a few larger prints without it, and after a few layers the corners would lift off the bed due to thermal contraction and ruin the entire print.

The Y axis is also a bit loose, similar to the X axis issue, with the bearing holders having quite a bit of play in them. Unfortunately, it isn’t quite as quick a fix as the X axis, as there is nowhere to put the cable ties. I’ve got some new bearing holders printed now to replace them. Just have to wait for the printer to cool down.

There are still a few more things that I need do before I have reliable prints:

  • New extruder. Something with a filament guide on top will be better. The filament slides off the hobbed bolt on occasion which stops anything being extruded. Very bad!
  • Spool holder. I need something to hang the spool on to allow it to unroll smoothly.
  • Electronics holder. The wiring is a mess and I’ve seen a nice electronics tray that will hold the circuit board and allow me to trim the wires down to a better (and tidier) length.
  • Z Axis stabilisers. Not sure if this is really necessary, I’m not seeing much wobble in the Z, but I may as well put them on there for completeness sake.

Of course, once the reliable prints are coming off, I may be able to reprint some parts and get the Huxley to work too!

However, the mechanical part of the printer is not the only bit that needs tweaking. Slicing the models is another area that needs a lot of work. This defines the layer height, the speed, amount of extrusion, amount of infill, etc. I’m slowly getting things homed in to a good quality at a fast enough speed that I’m not waiting for days for a print.

I’ve already had a few requests for things to be printed, and I’ve got a whole list of them too. I’m off for two weeks soon, and have a bit more filament on order, so I should hopefully have everything stable, tweaked, and reliable very soon!

Apr 262012
 

I got a stable flight out of my quadcopter at last.

I played it safe, and took it to the parents’ house seeing as they have a larger garden than I do, and made a few test flights. Only a low level hover, but it was controlled, albeit very roughly. Just goes to show how much practice it is going to take before I can start flying it properly. It wasn’t the most stable of flights I must say, I think amongst other things the propellers and motors all need balancing. It all was going fairly well until I got a bit to cocky and lost control. Only broke a propeller, so not too bad. Since then I’ve also secured the flight controller (an OpenPilot Copter Control) a bit better, which will hopefully keep it level and prevent any major drift and I’m going to make sure the motors are balanced. One recent purchase was a pan/tilt platform so I can put a cheap cam on the front to get a birdseye view of the flight. I’m very tempted to get a full FPV rig too, but I think it’ll be better to walk before I run.

Initial flights were in a + orientation, with one rotor being at the front. I’ve since changed that to an X orientation which means that there are two rotors at the front and the forward direction is in the middle of these. This makes attaching a camera a lot easier, and is the prefered orientation for FPV flying, so might as well get used to it from the start. I could do with some coloured propeller blades so that I can see which way is forward from a distance. Either that, or I may attach some LED strips to the two front arms.

In other news, I’m just building a new hotend for my printer. After the last .5mm one backed up, I tried the .25mm nozzle I got but I think that was a bit too ambitious. After a few hours of tweaking settings, I still couldn’t get a decent reliable print out of it. I’m just waiting for the fire cement to set properly on the new one, and then I just have to solder the wires onto it and mount it. One thing that is being a pain is the thermistor legs are very thin and fragile. I’ve already broken two and they aren’t the cheapest of components. They definitely need to be handled with care and strengthened up.

I also nearly melted another MOSFET buy hooking up the heated bed. Checking afterwards, the bed has a very low resistance (approx 1.5 ohm) which means the MOSFET gets very hot rather quickly. After a bit of digging in the forums, it was suggested that I put a heatsink on it. Nice idea, and easy solution, except the Sanguinololu board that I’m using has very little room to attach one. I’ve got a few different ones to try, and hopefully I can get one fastened on.

So, if the hotend is set by this evening, I may get chance to hook it up and give it a test! I may actually finish this project at some point!

Apr 132012
 

Easter weekend started off well, I actually got a test print off my printer! Unfortunately, the nozzle started to back up and got clogged, and whilst I was trying to clean it out (needed the heat one to do this) I seem to have shorted out the heating resistor which had the knock on effect of over heating the MOSFET, which also melted the plastic connector next to it. Not really a big issue, except I had no spare MOSFETS handy, so back to RS to order them. It did give as rather bad headache after a couple of hours in my cellar after the meltdown. Must get some better ventilation installed at some point!

On the plus side, the couple of small prints that I got off were rather good, and looked to be quite accurate. Once I get the replacement parts installed and a clean (or possibly new) hotend I can get some better prints off, along with some pictures and video! The hotend is turning out to be the most difficult part of the whole build, and also the part that seems to be least documented. Lots of different types of hotends are available on the reprap wiki, but none seem to be a clear choice, and also very little info on mounting them to the actual printer. Once I get that part worked out properly, it should just be a case of a bit of calibration!

The parts arrived after the long weekend, but by this time I’d come down with a bit of a cold. Nothing bad, but enough to put me off doing any intricate electronics. Of course, typically, the weekend is now approaching and I’m still feeling bunged up. Quite an annoying cold this. Also have a few extra hotend types to try.

In other news, Good Friday was the Alex Reunion. The Alex was a night club that a large number of people went to regularly in Lancaster, especially on its GRIP (Goth, Rock, Indie, Pop) nights. It was a very popular place, and had a great community behind it. The club closed down 10 years ago, and I thought it was high time that someone got everyone back together. That someone turned out to be me! The wonderful manageress at the Yorkshire House let me have the function room upstairs for free for the night, knowing full well that it would be busy with a good group of people. Nice easy (but busy) night for the staff. Thanks to the notoriety of the Alex, I had to do next to no publicity. All I did was to create an event on Facebook, and that was enough to get me worrying about the capacity of the venue, and the number of people turning up.

So, Good Friday came around, I got some old posters photocopied (thanks Sarah), a projector was loaned to me (thanks Coops), and I totally cheated on the DJing! Sarah also loaned me a banner from the very last night at the Alex. A roll of paper was hung on the wall and pens supplied for people to write their memories and thoughts. Sarah has lovingly looked after this for the last 10 years and it took pride of place on the wall of the reunion. Thanks to the projector, I also had nearly 300 photos projected onto the back of the stage, which kept people enthralled when they first arrived. Lots of good memories. The playlist for the night was one of the most fun, but most difficult, part to do. So many classic tunes were requested that it was very hard to narrow the selection down to just one nights worth. I also had to exercises my geek, to cut out any silence from the end of the tracks. A quick bit of scripting and I had a program called sox cutting off a few seconds here and there from all the mp3 files I had selected. It actually cut enough off for me to be able to squeeze another track in! Song editing, and using rhythmbox, meant that the sum total of work I had to do for the night was to press play and leave it. I wanted to enjoy the night too, and not be stuck behind a computer!

I’m happy to say that the night was a screaming success. The room was packed, I had people dancing all night (Kari and Dany especially!), we made the walls drip, and lots of singing to the last few songs. The comments left on the Facebook group for the Alex were wonderful and made the grin I already had even bigger. There have been lots of requests for a repeat performance, but currently I have no plans. Definitely won’t be one this year, but I may be able to be talked into an annual one.

For anyone interested, here is the playlist from the night:

  • Black Hole Sun – Soundgarden
  • Would – Alice in Chains
  • Animal Nitrate – Suede
  • Common People – Pulp
  • You Love Us – Manic Street Preachers
  • Love Spreads – The Stone Roses
  • Nuclear Holiday – 3 Colours Red
  • Paranoid – Black Sabbath
  • Symphony Of Destruction – Megadeth
  • Walk – Pantera
  • We Care A Lot (2009 Remastered) – Faith No More
  • Enter Sandman – Metallica
  • Blue Monday – Orgy
  • Don’t You Want Me (Original Version) – The Human League
  • Kick In The Eye – Bauhaus
  • Vision Thing – Sisters Of Mercy
  • Sin – Nine Inch Nails
  • The Beautiful People – Marilyn Manson
  • Sonne – Rammstien
  • (Can’t You) Trip Like I Do – Filter/The Crystal Method
  • Firestarter – Prodigy
  • Def Con One – PWEI
  • Jump Around – House of Pain
  • Anthem for the Year 2000 – Silverchair
  • Monkey Wrench – Foo Fighters
  • Chop Suey! – System of a Down
  • I Alone – Live
  • Celebrity Skin – Hole
  • Hey Dude – Kula Shaker
  • Rocks – Primal Scream
  • Place Your Hands – Reef
  • Girl From Mars – Ash
  • Pure Morning – Placebo
  • When I Grow Up – Garbage
  • Drop Dead Gorgeous – Republica
  • Laid – James
  • Son of a Preacher Man – Dusty Springfield
  • Torn – Natalie Imbruglia
  • Stuck in the Middle With You – Stealers Wheel
  • The Size of a Cow – The Wonder Stuff
  • Come Out and Play (Keep ‘Em Seperated) – The Offspring
  • Wuthering Heights – China Drum
  • Basket Case – Green Day
  • All the Small Things – Blink 182
  • The bad touch – Bloodhound Gang, The
  • Girls – Beastie Boys
  • My own worst enemy – Lit
  • A Certain Shade Of Green – Incubus
  • Blind – Korn
  • Sway – Coal Chamber
  • Davidian – Machine Head
  • Killing In The Name – Rage Against The Machine
  • Smells Like Teen Spirit – Nirvana
  • Screamager – Therapy?
  • Weak – Skunk Anansie
  • Riverflow – The Levellers
  • American T.V. – Terrorvision
  • Stupid Questions – New Model Army
  • Rearviewmirror – Pearl Jam
  • Been Caught Stealing (2006 Remastered Album Version) – Jane’s Addiction
  • Add It Up – Violent Femmes
  • I Wanna Go Where the People Go – The Wildhearts
  • Epic – Faith No More
  • Welcome To The Jungle – Guns N’ Roses
  • Rag Doll – Aerosmith
  • Poison – Alice Cooper
  • Creep – Radiohead
  • Under the Bridge – Red Hot Chili Peppers
  • Hey Jude – The Beatles
  • Birdhouse in Your Soul – They Might Be Giants

 

Apr 042012
 

I got a nice parcel delivered today. Two nicely build hotends for my new Prusa Reprap. After all the issues with the Huxley, the Prusa has been a total doddle. The last piece I needed for it was a hotend, and after having some issues sourcing some of the components, I had a look on eBay for any pre-built ones. I found one guy shipping some from Poland that looked perfect for what I needed, not only did they have all the molex connectors already done in a way that is compatible with my Sanguinololu board, but he was offering a twin pack with one .5mm and one .25mm nozel. Oh, and a pre hobbed bolt too!

Prusa build

So, with the body built and the electronics tested, all I have to do is figure out how to attach the hotend and I can start building. I’ve already posted a video a few days ago of the body moving nicely, which is further than I ever got with the Huxley. Never know, maybe by this weekend I’ll be able to print something! Just have to finish work first.

Here’s the video of the first test of the electronics.

Prusa build

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