All posts by Darren Poulson

Another success. The Reprap prints!

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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!

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

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!

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.

Well, had an eventful three weeks in the states, but I’m back now and eager to get on with things!

The first two weeks of me being away were taken up with work as part of my regular visits to the states to see everyone in the office. I’m glad I was out there at this particular time thanks to an email received in the early house of Monday morning, informing me that the american arm of 2ergo had been sold to a company called SoundBite. A bit of a shock to say the least! Still, the new company sounds promising and once I have a few HR things sorted out I’m sure things will be fine. As long as I have servers to play with I’m happy!

The last week of stateside was spent with my partner in crime, sightseeing around Washington DC. We both love museums, and these took up the majority of our time, along with a trip to the National Zoo, and a fantastic Segway tour of the city. Many thanks to Carly, our guide from Segs in the City. There ended up only being us two and the tour guide, so we could go at our own pace and managed to get a lot more out of the tour than we would have if we had a bigger group.

Segways are great fun… Hmm, I may have to build one!

Here’s a few photos from our trips.

• Museums
• National Zoo
• Segway Tour

Was a great week off, and a first for us to both be abroad in the same place at the same time!

But, I’m back home now, and back at work. I’m hoping this weekend I can get my quadcopter flying again if the weather is nice, and to also get a big chunk of my new Prusa based 3d printer built now that I have all the parts.

I didn’t want to do it, but I’ve had to give up on my Techzonecom model Huxley printer. I’ve spent another couple of hours on it today and decided it just isn’t worth the hassle. It certainly helped that I found someone on eBay selling printed parts for a Prusa for a decent price.

The Huxley isn’t totally lost, there are many options open to me to get it working, once I have a working printer. Its a chicken and egg problem.

One thing I do have to say, and it seems I’m getting backed up on the forums about this, is never buy anything from TechZone Communications. They seem to have lost the plot and have a long stream of unhappy customers, as well as a below par product. Besides missing parts in the kit I received, and electronics that burst into flame, it also in my opinion is a poorly designed reprap printer. Captive nuts are needed to be melted into the plastic parts, the extruder is external to the main printer with no easy way to mount it and the electronics are just shoddy.

I bought my kit via a UK company called RepRap Central who it turns out are resellers of TechZoneCom kits. I didn’t know this before I bought it, and they don’t make any mention to TechZoneCom. They do however sell other brands of printers, including MakerBot. Communications with RepRap Central are pretty good, and they do have good prices on filament.

So, I’ve got the plastic parts for a Prusa on order, I’ve got plenty of hardware, I’ve got a completed Gen 7 electronics kit built. Hopefully the parts will be arriving next week, and I can have a start at building it. Unfortunately, I’m off to the states for a while for work, so its going to get put on hold for a little while.

Hopefully the Prusa will be a little easier.

The replacement electronics for my Reprap Huxley arrived today at long last. I’ve had them plugged in for nearly an hour over dinner, and no flames. Good start!

I think this evening and weekend are going to be devoted to trying to get my printer working. I hope nothing else turns out to be faulty with the kit I bought. I’m already very disappointed with the quality of it overall. If I had a better understanding of the whole Reprap process, I would have gone with just ordering the plastic parts from somewhere and building my own. I’m sure I’ll do a full write up on it at some point.

To recap, I’ve got the frame built with all the stepper motors mounted and the belts in place. So all(?) I have left to do is:

• Calibrate the electronics
• Finish the extruder – Just needs the motor mounting I think, and the tube inserting.
• Finish the hot end – All gunged up, just needs the electronics attaching to the nichrome wire and thermocouple.
• Mount the hot end
• Mount the end stops

Once all that is done, I may actually be able to start testing. The testing is going to be a long process I think, I very much doubt I’ll be printing quality objects from the start. Lots and lots of wasted plastic doing test prints, levelling the base, etc. Still, if I can finish this weekend with an actual printed object I’ll be happy. Roll on 5pm when I finish work!

I haven’t done much in the way of geek things over the past week, and I’ve been meaning to have this rant, so here we go.

I like gadgets. I have a lot of them, some may say too many, but I say not enough! I’ve even had an e-reader, and am quite impressed with e-ink technology. What I don’t like is the actual e-books, or rather how they are sold.

Nothing can compare to an actual physical dead tree version of a book. Its great to have a book in your hands, its just a much more pleasant experience. E-books however are handy. They’re great for taking on holidays, much easier having a device with hundreds of books on than carrying around a stack of heavy paperbacks. Also, a lot of documentation comes as downloadable PDF files which is so much easier to read on e-ink device than an LCD screen.

A lot of my issues surround DRM and price.  I’ve got issues with DRM on any format or media, but on e-books it is especially bad, compounded by the fact that e-books are generally only a little cheaper than their physical counterpart.

With a real book, you can

• Lend it to a friend
• Give it to a friend
• Take it to a second hand shop, and swap it
• Keep it forever

All these points have one thing in common. Ownership. You never actually own an e-book, you’ve just got it on long term loan from the seller. You aren’t allowed to resell the book at all, and even lending it to someone is hard enough. Woe betide if you want to try a different e-reader, you’re left with having to either illegally strip the DRM from the book, or buy it again.

If the seller goes out of business, you will more than likely lose access to your books. Don’t think this will happen because of the size of the company? Well in 2007, Virgin’s downloadable music store decided it wasn’t making enough money, so withdrew from the business. Suddenly all the music you bought through that service was unusable. Or maybe the seller decides that they sold the book by accident, as Amazon did with 1984. They removed access to the book to stop you reading it.

The last point above is not just about DRM or ownership as such, its down to the fact that the digital world moves so fast. The current e-book formats may not be around in five or ten years, but I have books on my shelves that I remember buying whilst still at primary school, nearly thirty years ago. I also have books that are older than me, that were picked up from second hand bookshops. These are out of print and unavailable from any e-book retailer. In another thirty years, will I still have a functioning e-reader that will read the current formats? Projects to read digital media that is less than twenty years old are a big undertaking these days, but I’ll still have books on shelves that I can simply pick up and read.

Of course, to compound all this, e-books are sold at a ridiculous price. As I’ve already mentioned, you are simply renting these books and never really own them, but the price difference doesn’t reflect this. Some e-books are still being sold at hardback prices, when the actual cost of manufacture is a moot point. A lot of my previous issues could be overlooked if they would simply charge a reasonable amount for the books. If a book was under a pound to purchase (rent), then I would think nothing of paying for it, and I may even take more of a risk on an unknown author. I find myself being put off buying a book these days, even a physical one, because the prices are so high. The pricing model has worked for smartphone apps, so why can’t it work with books?

I love reading, I love books, and I love gadgets. Unfortunately there is no way currently for me to legally use e-books. If I want an MP3, I buy the CD and rip it. If I want to store my DVDs on my network, I can rip them too if they don’t already come with a digital version. This can’t be done with books unless you go to the trouble of buying or building a book scanner. I could use the kindle app and then strip the DRM out of the file, but I don’t want to do this as I shouldn’t have to, and I’m not going to give Amazon any of my money whilst they still insist on running this monopoly. I do need to say, it is not just Amazon. All other e-book sellers work in the same way, and this could be due to the publishers, but it is still wrong.

Right, rant over. I’m going to go to bed and read a good, dead tree, book.

There is a 'copter there somewhere.

Well, the quadcopter flew briefly. Twice.

I managed to get a very short flight before a tree jumped in my way and I lost control. Thankfully not much damage, just some smashed blades and a couple of motors had broke free. I quickly repaired it and went out for another try.

Unfortunately, the second flight ended with quite a bit more damage. I think the main frame had been weakened by the first crash, so after a bit of a heavy landing, it totally buckled. Still, the second flight did last a bit longer, and it seemed to fly well. Out of all this I’ve learnt a few things:

1. Stay out of the way of trees
2. 10mm dowling is not strong enough to survive a heavy landing
3. The frame needs to be a lot more robust and accurate to fly steady.

So, with this new knowledge, I’ve ordered a frame kit which will hopefully arrive in a few days and prove to be a bit more reliable. Especially as it has landing gear, which my frame didn’t. This should keep me going until I finish my printer and can design a nice custom printed ‘copter. Might also have a go at balancing my motors and props.

Still waiting for the replacement parts for my printer. Some arrived the other day, but they forgot to include the main circuit board. ie, the part that burst into flames and I can’t progress without. Not impressed.

Since deciding to renew my interest in electronics over the past few months, I’ve tried various websites for supplying components and parts, along with some good sites for learning and ideas. I thought I’d do a quick write up of some of my favourites and put it all in one place.

Firstly, lets start with components. You will always need somewhere to get all your bits from, as well as tools and consumables. Here’s a few sites that I’ve found both handy and reliable. I do like to be able to get everything I need from one place, but I haven’t yet found a one stop shop for everything, but I have managed to narrow it down to just a few that will satisfy most of my needs.

• Bitsbox – This is a great site to get your basic components from. They are cheap, well stocked, and have a nice simple website to use. You won’t find things like Arduinos, or Sparkfun kits, but you will find just about all the basics you could ever need. Components can be ordered in singles, or bulk, and delivery is pretty rapid. I tend to use Bitsbox to stock up on standard things like resistors, capacitors, common chips, and other non specialist components.
• Proto-Pic – This is where you go for the more ‘building block’ style components. Things like Arduino, Sparkfun, sensors boards, breakout boards, etc. Great place with a nice easy to use website. I do find that I need to watch my spending here. It is too easy to keep loading up the basket with fun parts, especially shiny things like LEDs. There is a lot going on now in hobby electronics where you buy pre built component modules and link them up for a project, rather than scratch built circuits. Good communication from the staff here, and will part ship your order if they are having trouble with stock, instead of having you wait.
• Cool Components – Very similar to Proto-Pic. You should be able to find what you want in one of these two stores. I’ve dealt more with Proto-Pic than Cool Components, but more for familiarity than any other reason.
• Jeelabs – This is a slightly odd case, and is a more specialised shop than the rest. I’ve been working a lot with JeeNodes, and this is the place to source them from. Its a one man shop, but he is designer, builder, and shipper. He also provides a lot of information, not only on how to use his products, but also in general electronics knowledge.
• Unmanned Tech – Not exactly in the electronics section, but this is where I get my quadcopter autopilot components from. I just wanted to mention it here because the support that is given is great. Very friendly and actually want to help.

Next, lets look information sites. These are places to go for learning more about electronics, techniques, and news.

• Jeelabs Blog – As mentioned above, Jeelabs provides JeeNodes, along with other modules to go with them. The blog provides a lot of information about how to use their products, how they were designed, and also general information such as circuit design, how to improve your arduino sketches (especially making them low power), and walks you through good ways to measure and bug trace your own circuits. Well worth following.
• EEVBlog – A great, fun blog by a mad aussie. (Are there any other types?!) He has a regular video blog on a fairly wide range of electronics subjects, including reviews on lab equipment, tear downs of new gadgets, and instructions on circuit design. He’s now making a living from this blog after having many years work experience in electronics. Videos are released on a pretty frequent basis and are well worth a watch just for his enthusiasm!
• Instructables – This site is just fantastic. People from all over the world with a passion for making things can upload full build instructions to this site for all to read and reproduce. Its not just electronics here either! Anything that involves making things can be found here, from needle work to metal work! The information is free, but it is worth signing up for a full members account which allows you to view the instructables in a single page, rather than multi-page, and also download it as a PDF. Handy for putting onto an e-reader or similar. Great place to look for ideas for projects, or help on something you’re working on.
• Makezine – Makers are taking over, and this is the place that pretty much summarises the movement.
• Thingiverse – If you have a 3d printer, laser cutter, or cnc mill (or at least access to one), then you can find many actual objects available to download to be produced. The idea being, if you need something, and design it, you can then upload it to this site for anyone else to produce for themselves. An open source object library.

Thats it for the main part. A few honourable mentions go to RepRap for all your 3d printing needs, and also Youtube. There are many many videos there that are well worth a watch.