Archives 2012

In a few other blog entries, I described getting and modifying my laser cutter/engraver. You can read these here:

• Unboxing
• Modification
• Final touches (coming soon)

This post however is a review on the laser, as it comes from the eBay seller. I’ve broken it into a few sections, and pointed out where my experience has differed from other stories I’ve heard online.

Packaging and Delivery

So, the packaging wasn’t too bad. It was obviously shipped from China, and just redistributed from Portsmouth with no actual unpacking. The outer wooded crate was quite battered and falling apart, with lots of packing tape. Thankfully, inside the crate was lots of polystyrene, and the actual device was in good shape. The x/y carriage was secured with a bit of ribbon, and all electronics were well secured. Now, from various other blogs, I know this was very lucky for me as many other people complain of loose connections and missing screws. About the only complaint I have on the whole packaging front is the way the water cooling tubes were tied in knots. This put some rather bad kinks into the tubing which could restrict the water flow.

Software

The software is the worst part of this device, which is why I threw it away as soon as I’d tested the machine was working. That being said, I can give a few observations from my short lived interaction with it. First off the software is very much Chinese with very basic translations. If you haven’t got the Chinese localisations installed on your computer, then the install process will show lots of strange characters, not that it will be much better unless you can read Chinese. This means installing the software is pretty much blind.

If you manage to stagger through the install process, you’re presented with a whole wealth of configuration options, drop downs, and a big canvas area. At this point, I managed to get one of the example files loaded and the laser tested. After that I didn’t really use the software again. I do know you can import Corel Draw pictures, and possibly even get a plugin of Corel Draw. There are lots of videos on using the software, and if you don’t want to customise the machine, you’re best off watching them.

Laser

Once again, from reading other blogs, I believe that I was rather lucky in that the test fire worked first time. Many other people have to go through an alignment process of tweaking the mirrors or even actually moving the whole laser tube. I can see why they would have these issues as this whole machine isn’t what I’d call well built. Lots of rough edges and no real finish to it in any way, but you get what you pay for. The extractor unit is very basic, and the slot for it is not a good fit. It is well worth taping it into place to get a better seal, and hence better suction to extract the fumes. For cooling you get supplied with a small aquarium pump which needs submerging in a bucket of distilled water to keep the laser cool.

The main area with the x/y axis is actually not too bad, with it all running quite smoothly. The x axis is very slightly out of alignment, which is something I still have to correct, but overall I’m fairly impressed with this. The axis are controlled by standard stepper motors, with endstops being hall effect sensors. The main drawback however is that the cutting area isn’t sealed, so the extractor doesn’t work as well as it should do.

Safety

I think this deserves a section all to itself. This device is built with absolutely no safety features at all. The laser can be running with the lid open to allow people to put their hand in the (invisible) beam of the laser, there are no interlocks either to stop the laser if the water isn’t flowing or the extractor fan fails. I could see no fuses at all within the electronics enclosure, and from one blog I read it was pointed out that some short circuits could put 20kV through to the control panel. Also, the cutting area is not sealed from the electronics area either, so fumes can easily pass through and escape.

Summary

You get what you pay for. This is a very cheap (for laser cutters) machine, with no regard to build quality or safety. If you want to get a laser cutter that works out of the box for commercial reasons, then spend three times more and get something better. That being said, if this is for someone who is technically adept and has experience in cartesian robots such as Reprap or other CNC machines, and wants something to experiment with, this could be a good purchase. My other posts describe what needs to be done to get this working to an acceptable standard, and it will cost a bit more money. I’ve probably spend another 50% on top of the original cost to get it working properly with safety features. If you do go down that route, then this can turn out to be a nice little machine for a hobby or hackspace. Once tuned and tweaked, cutting materials up to 5mm may be possible.

I’m pretty happy with it, and it was a good way to experiment with laser cutters without spending thousands of pounds. I am already thinking about going the entire homebrew route for my next one, if this turns out to be useful for me.

A slight detour from laser based articles. We’re off on another convention next weekend, and Joy is taking some special gin. 🙂

A lot of people make Skittle vodka by dumping a load of Skittles into bottles of vodka, but this involves a lot of filtering afterwards, and still leaves the vodka cloudy. By using Jolly Ranchers you can totally skip the filtering stage, and they also dissolve a lot quicker.

So, here’s the recipe for making Jolly Rancher Gin. Not exactly hard, but thought it was worth writing up.

Requirements:

• Gin – a 1.5l bottle will be more than enough. You may have enough with just 1l.
• 5 x 250ml flasks. We got these: Eddingtons Roma Bottles 250ml x 6
• 1 x 14oz bag of Jolly Ranchers. People in the UK can get them from here: Jolly Ranchers Original – 396g

Thats it, nothing special. Start off by making sure the bottles are thouroughly cleaned if you’ve just got them from the distributor. Then open your bag of Jolly Ranchers and start sorting them into the five flavours

 You will need approximately a dozen of each flavour, but it will depend on how many of each flavour comes in the bag. No doubt you’ll find too many of one, and not enough of the other. Next, unwrap all your sweets and start popping them into the bottles.

Once the sweets are in, start filling the bottles with gin. Slowly fill up until you hit the bottom of the neck. Once filled, simply put the lids on and give them a good shake.

All that needs to be done now is to wait for the sweets to totally dissolve. This takes between 12 and 24 hours, and will probably need a shake or two to stop it forming into layers and to speed up the dissolve.

Thats it, dead simple, and so much easier than skittles. Enjoy!

Last week I took delivery of a nice laser CNC engraver/cutter. This was a very cheap chinese machine, model number K40-III. When I got it, I knew the controller and the machine itself were very limited but there was an open hardware project call LaOS that I hoped would solve some of the issues. Couple that with a bit of my own customisation, hopefully I am going to end up with a fairly decent machine, for a lot less than a commercial model. I’m not the first to attempt this, as these machines are very common on eBay. I haven’t seen any success stories on my browsing so hopefully I will be the first.

I’m not going to put all the details on here, as I am updating the project wiki so its all in one place. This is going to be more of a log of what I do, so if you want the nitty gritty details, take a look at the wiki page for this machine.

So, on with the log. After making sure it was all in working order, the next job was to figure out what all the connections did, and what to do with them. Starting with a load of photos, I started to trawl the net. The controller board I knew was a chinese model, so punching the numbers off the silk screen into Google I managed to find a pdf with the technical details. One drawback, it was all in chinese! Thankfully Google translate came to the rescue and gave me enough details, coupled with details on the Laos wiki about other laser machines, to know what each of the connectors did. The other part that needed tracing was the power supply. Thankfully this turned out to be a simple case of checking continuity between the pins and the components on the control panel. After all this investigation, I knew how the stepper motors, the endstops, the control panel, and the power were connected.

The only difficult part was how to control the laser. This is a bit I struggled with as the documentation for the LaOS project is still being written, and there seemed to be multiple ways to control the laser. One of the power supply connectors allowed me to fire the laser, which was great for testing, but it didn’t honour the laser enable/disable button which I would rather leave in place and active. There was also another connector pin that was labelled as Laser, which in theory will control turning the laser on and off from the controller board. Experimentation will be needed I think.

With this knowledge in hand, I purchased a LaOS PCB, along with the PCB for the i2c LCD addon, and started putting the electronics together. Again, due to the project wiki being fairly new, and the team behind it being very small, it wasn’t quite as easy as other projects I’ve encountered such as RepRap. I’m fairly confident this will change over time, and I know I’ll be going through the wiki adding information once I’ve got it all working.

Once the electronics were constructed and ready, I unplugged the old controller, plugged in the new one, loaded up a test firmware and turned it on. I rather quickly encountered my first problem. A total school boy error of putting the wrong voltage capacitor on the board meant it blew up in my face… literally. Still, no harm was done to either the board or myself, apart from a bit of an adrenaline rush. I quickly swapped out the old capacitor with a newer one of the correct voltage and plugged it all in again. Nothing blew up this time, and I could confirm that all the voltages seemed correct. Next step was to try some of the motors and end stops. Moving the head back and forth showed that both home position endstops were working fine thankfully, and were inverted so that they turned off when homed. I guess its safer that way, and it told me I needed to set that up in the configuration.

Happy that things seemed fine, I put the real firmware onto the board and fired it all up. Success… kind of! The X axis homed nicely, but the Y axis sat and juddered in place. After a few posts on the forums, and a lot of messing with config files, and checking of connections, finally it homed to the correct position. With that seeming to work, I fired up the interface software called visicut, and tried to send a few test files to the machine. Well, things moved, but not exactly in the right way. Still, better than nothing and I was fairly certain that it was all down to settings in the config file. I was beginning to understand that the config file is the hardest part of setting it all up, but finally after a lot more tweaking of the file, I had both axis moving in the correct way and the correct amount.

Next came the laser. In some ways, I was dreading this. So far I’d been messing with things I knew about from building a couple of reprap machines, namely stepper motors and pololu stepper drivers. I was fairly confident if I blew either of these things, then I could fix or replace them. The laser was something totally new. However, from reading the documentation, and putting a multimeter onto the connection marked L on the PSU, I was fairly certain all I needed to do to active the laser was to pull the L pin down to ground. All this took was a single wire from L to one of the Laser On pins on the LaOS board, and the other Laser On pin I simply tied to a handy ground point (ie, the screw terminal on the board that came from the PSU ground).

With a little bit of trepidation, I powered up the printer and started visicut. I loaded a simple rectangle file to test with, and hit the execute button. A nice little rectangle was cut out of the test bit of card! Wow, that was easy! To say I was happy would be a little bit of an understatement. I quickly grabbed a bit of acrylic I’d got to test with and fired up inkscape to draw something. I only wanted something simple, so I decided to try and engrave my name into the acrylic, so a quick click on the text button, and I typed my name in. Up to the extensions menu, and select Lasercut Path and the image I created was loaded up in visicut. A click on engrave, and execute, and my name was being etched into the acrylic! It turned out rather nicely! 🙂

All in all, I’m very happy. I got a cheap machine off eBay with a lot of limitations and with the help of an Open Source hardware project, I’ve turned it into a networked laser CNC machine. It is still limited in the strength of the laser and the bed size, but I now feel confident enough that if I end up using it a lot, I can get a higher end cutter and convert that.

I’ve still got a way to go yet on this project. The CUPS driver isn’t working properly, so I’m relying on using visicut to do the actually printing work, but that isn’t too bad as it is a pretty easy to use program. I also need to put PWM onto the laser output so that the controller board can vary the laser cutting power itself. Lastly, there is the i2c LCD module to get working. For some reason if I plug the module in, the controller board won’t boot properly, but I haven’t done any investigation yet to find the reasons. Oh, and I think a few safety measures are needed such as a water flow sensor and lid sensor which deactivate the laser in the case of anything not working… better safe than sorry!

So, the other day a large crate arrived on my doorstep.

Hmm, what could this be?

Yep, I treated myself to a new toy. A 40W CO2 powered lase CNC engraver/cutter (Model K40-III). Now, this isn’t exactly a top of the line model, infact it is probably the cheapest you can get one without going down the DIY route. It is a very cheap device from China, with the most basic of functions. Basically an X/Y axis with a couple of stepper motors, a 40W laser, and a very basic controller board. The main drawback (besides all the instructions being in Chinese) is the fact that it will only work with the rather rubbish software that comes with it, and that will only run on Windows XP. That isn’t going to work for me, especially after finding an old XP laptop and trying the software out. To say that it is buggy and un-userfriendly would be an understatement.

Thankfully, I knew this before purchasing it from eBay. There is a great open hardware project call LaOS, which is designed to replace these cheap and nasty controller boards on these types of lasers. So, armed with a PCB from the project, a bunch of components, lots of pictures of the existing setup, and my trusty multimeter, I am going to set about installing a nice LaOS board. The benefits of this new board is the fact that it adds network capabilities. It becomes effectively a network printer, controllable from a linux machine as a Cups based printer. This way, programs like Inkscape to draw the desired output, and send it to the machine. A much easier way to control it.

An LCD display with local controls is also available as an addon to the main LaOS board. All in all it should turn this cheap basic machine into something fairly usable. It should then be able to compliment my printer for making things, and Joy should also be able to use it for some of her arty stuff.

Testing!

So, first stage was to do a few tests to make sure it had survived the journey and was in a working condition before I break it. The front panel has a handy laser test button to let you fire the laser without having a computer hooked up. Needless to say, after hooking up the water pump to cool the laser, I had a bit of fun burning things! 

Seems to be working ok

And with it hooked up to a computer with the rubbish software

About the best I could do with the software supplied

All seems good, so time to take it apart! Hopefully the next post will have a nice success story of a much improved machine

Unboxing!

Unboxed!

Thats a 40W Laser

Second part is here

This rant has been brewing for a while, and I’ve finally got chance to write down my thoughts on a matter that rather annoys me, and that is TV shows, or more to the point, the current method for watching them. It isn’t just limited to TV either, films come under the same category, although to a lesser degree.

The Problem

So, what is my problem with all this? Easy, I was paying Sky TV about £50 a month, to watch maybe 10 hours of shows each week. The rest of the time that I was watching TV was spent browsing through the program guide or watching re-runs of old shows. The whole TV industry is another one, similar to the music industry, that is stuck in an old way of thinking. When TV first came about, it was required for a central agency to broadcast the shows on a fixed schedule, there was no other way to get the information out to the viewers.

Cable and satellite came along later, but still it was required to broadcast from a central point. Now we have high speed internet going to the majority of the population, but rather than make it easier for us, its added a new layer of complexity to it. Yes, you can use Netflix, or Love Film, or iTunes to buy your TV shows and stream them to your TV, but to ensure that you get all the shows you want, you will have to subscribe to all the providers out there, which can start to cost a lot, not to mention the usage caps that ISPs put on their broadband packages.

This also doesn’t take into account initial air dates of shows, with the UK generally getting shows months after they first air in the USA. I signed up for Netflix to give it a try, and whilst it has a large catalogue of programs to watch, the latest series of shows don’t show.

The Solution?

What can we do about this? Well, I am by no means an expert (this is just a rant after all) and only have a rough idea of how things work in the industry, but surely there is a better way to distribute a TV show? A big broadcasting infrastructure is no longer needed, so why do we still have the middle man of broadcasters? Much like some musicians are doing, how about a TV studio puts their latest series up on the internet to buy and download? With technologies such as Bit Torrent, then the actual technical requirements would be rather low. I believe this would give quite a few benefits such as:

• Direct payment to the studios will mean a bigger share of profits
• No more guessing on the popularity of a show. If people like it, they will be buying it.
• The people pay for the shows they want to watch, so hopefully things like X Factor will not  be on our screens. Who’d actually pay for it?
• You can watch the episodes when you want. Big new series? Watch it when it first comes out and join in the discussions about it. Late to hear about a show? Catch up at your pleasure.

Of course there are a few drawbacks. Initial funding for a series would need to be found somewhere, which is where the current media corporations come in, and the networks have a lot of resources behind them that a small studio may not have access to, including sound stages and filming equipment. I would be very happy to spend the £50 a month on TV shows that I like, hopefully giving them a lot bigger portion of my money then they are currently getting.

For example, if I watch 10 hours of TV a week, then I’d just pay £1.25/hour for the actual TV I watch. Of course, the show would probably make the first couple of episodes free to get interest going, and perhaps offer the entire series for a bulk price, or even a discount on the DVD release. Free to air TV stations in the UK aren’t too bad, with various catch up methods, but none of these offer true freedom and each station has a different program required to watch them.

Current Experiments

This isn’t a new idea either, Sanctuary started as a budget web series which then got picked up by a network. YouTube is full of interesting regular shows (and cats) such as The Guild, Tabletop, Cocktails with Stan Lee, and is also now running ‘channels’ for collections of shows including Geek and Sundry, and the Nerdist Channel. I am finding myself watching more and more YouTube shows thanks to being able to see them on the main screen.

So, perhaps this is all just wishful thinking, after all the music industry is still trying to resist the change, but perhaps like the music industry it can be subverted by smaller outfits. We’ll just have to wait and see.

Its been just over a year since I started working from home with just a single day in the office each week, and over 6 months since I stopped even going in even that often. I thought I’d put down a few thoughts on how it has been for me, and some pointers if people are thinking of doing the same.

First of all, working from home is not for everyone, I’m just lucky that it suits my personality. It can be very quiet and I have actually gone nearly a whole week without leaving the house at times. For me, this isn’t a big deal and I am really liking the whole working from home thing. It has come in very handy for getting parcels delivered, and makes things like getting boiler services done or meters replaced a lot less of a logistics nightmare. I am also finding that I am being a lot more productive during the day, and the stress levels are nearing non existent!

Tips:

• Have a separate area to work in. Don’t try to work from the living room or similar. I have my cellar set up with my main computer and all my hobbies, but if I tried to do actual work from there it would be a failure. I converted the front room from a spare bedroom into an office (with a sofa bed for visitors). This has many benefits, not least of which is I can close the door if I don’t want to be disturbed. Also, it gives you a definite feeling of finishing work when you leave the area, just the same as if you left the office to go home.
• Work set hours. If the rest of the office workers do 9-5, then so should you. Take a lunch break at a reasonable time, and don’t take too long. It is important to be disciplined with yourself on this count. Its too easy to fall into bad habits and you will find your work suffering and your colleagues getting annoyed at you.
• Social media helps. Not just facebook, but corporate chat systems, email, etc. You do manage to avoid a lot of the office politics that might go on, but you also need to make sure that you build good relationships with the other staff. Don’t just barge in to chat, at least not at first, but if you’re talking about work, have a bit of a chat afterwards about what you’ve been up to.
• Make an effort to go to the office on occasion. Nothing beats real face to face time. It will also remind your colleagues that you exist!
• Be organised. You won’t have people around you to remind you about tasks they’ve requested. Keep a list of things you are working on, prioritise it, and keep it up to date. At the end of the day, make a task list for the next day. This tip isn’t really just for people working at home, and is a useful thing to do even in an office, but it is more important to do if you are home working.
• Arrange daily catch up meetings. This is something that was initiated at my work and is something I find really useful. For my work, the process is: At the end of each day (my time) we have a quick ‘standup’ meeting with all the remote workers to catch up on what we’ve done since the last meeting, and what we are planning on doing. This is a process taken from the agile development process, and by designating it as a standup meeting, it is kept as short as possible. Only the tech people are allowed to speak and very little, if any, organisation should take place. It is purely for information. Other people can listen in if they wish, but must stay quiet. It helps keep you connected with your colleagues, and forces you to be organised and methodical with work.

Of course, I’ve tried to be general with the above information as my job carries its own quirks that have to be adapted to, not least of which is that most of my colleagues are in a different time zone, and so are working until gone 10pm my time. That coupled with the fact that I also do a lot of on call work means working hours tend to be flexible, but that was a career choice I made a long time ago. Working with a different time zone does have a couple of big advantages, especially in my role. For starters I can get a lot of the server work done whilst most of America is still asleep, and it also gives me a lot of uninterrupted time to get stuck into things. I then have the afternoon at work to field questions from my colleagues and help them out.

So in summary, if you don’t mind being on your own for extended periods of time, and have the discipline to work unsupervised, then home working is a great option with a lot of benefits. If you enjoy the company of other people and general office banter, then working from home will rapidly drive you mad.

Well, I’m more or less recovered now from another convention weekend. Yet again, Sean Harry has proven that he can throw a damn fine party. This time it was the 3rd Annual Vampire Ball held at the Renaissance Hotel, Heathrow, London. It was my sixth convention since I was introduced to them in 2010, and my third one at the Renaissance. Its a fantastic venue with friendly staff who don’t mind the insane antics of a bunch of geeks as they take over the lobby. We decided to travel down a day early so that I was more recovered after the long drive. I’m so glad we did seeing as it took over six hours to drive there thanks to the M40 being at a standstill. It also gave us a chance to catch up with some of the other regulars.

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Ok, I think this cartoon sums it up…

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So, been a while since I’ve done any updates, but then I’ve been a little busy recently. Since my last post I’ve been in the states working again. This time, not only Washington, but Boston too. Anyway, not much to talk about on that, just lots of flying and propping up bars in hotels.

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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!

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