tag:blogger.com,1999:blog-78494995550718403632024-03-05T07:37:49.841-08:00Greenarrow's Shedgreenarrowhttp://www.blogger.com/profile/06264757409706511516noreply@blogger.comBlogger15125tag:blogger.com,1999:blog-7849499555071840363.post-30950750703784228992010-10-05T12:32:00.000-07:002010-10-05T14:54:36.163-07:00Playing "Little Big Adventure" in Linux<span style="color: rgb(0, 0, 0)">Many years ago I played the game </span><a href="http://en.wikipedia.org/wiki/Little_Big_Adventure">Little Big Adventure</a><span style="color: rgb(0, 0, 0)"> but never got around to finishing it. Now that MSDOS has long gone I set about running it on Ubuntu 10.04 (Lucid Lynx). The game plays perfectly but requires a little tweaking.</span><br /><br /><span style="color: rgb(0, 0, 0);font-weight: bold;font-size:130%;" >1. Create an ISO From your CD</span><br /><span style="color: rgb(0, 0, 0);font-family:courier new;">$ dd if=/dev/dvd of=/home/yourusername/.dosbox/lba.iso</span><br /><br /><span style="color: rgb(0, 0, 0);font-weight: bold;font-size:130%;" >2. Install DOSBox<br /></span> <span style="color: rgb(0, 0, 0);font-family:courier new;">$ sudo aptitude install dosbox</span><br /><br /><span style="color: rgb(0, 0, 0);font-weight: bold;font-size:130%;" >3. Configure DOSBox<br /></span><span style="color: rgb(0, 0, 0);font-size:100%;">Create a directory for the DOSBox C drive:</span><span style="color: rgb(0, 0, 0);font-weight: bold;font-size:130%;" ><br /></span><span style="color: rgb(0, 0, 0);font-family:courier new;">$ mkdir /home/yourusername/cdrive</span><br /><br /><span style="color: rgb(0, 0, 0)">Edit the file ~/.dosbox/dosbox-0.73.conf:<br /><span style="color: rgb(0, 0, 0);font-family:courier new;">$ nano ~/.dosbox/dosbox-0.73.conf</span><br /><br /><span style="color: rgb(0, 0, 0);font-weight: bold;">C Drive</span><br /><span style="color: rgb(0, 0, 0)">Add this line at the end of the config file to make the C drive mount when you start DOSBox:<br /><span style="color: rgb(0, 0, 0);font-style: italic;">mount c /home/yourusername/.dosbox/cdrive</span><br /><br /><span style="color: rgb(0, 0, 0);font-weight: bold;">Sound Changes</span><br />When I first ran the game the sound was very glitchy and horrible. I made the following changes in the config file and it sounded perfect (8 bit tastic).</span><br /><br /><span style="color: rgb(0, 0, 0)">In [mixer]</span><br /><span style="color: rgb(0, 0, 0);font-style: italic;">rate=44100</span><br /><span style="color: rgb(0, 0, 0);font-style: italic;">blocksize=8192</span><br /><span style="color: rgb(0, 0, 0);font-style: italic;">prebuffer=50</span><br /><br /><span style="color: rgb(0, 0, 0)">In [sblaster]</span><br /><span style="color: rgb(0, 0, 0);font-style: italic;">oplrate=44100</span><br /><br /><br /><span style="color: rgb(0, 0, 0);font-weight: bold;">Load LBA on Startup (optional)</span><br /></span><span style="color: rgb(0, 0, 0)">If you want to use DOSBox only for LBA then you might as well load LBA automatically when DOSBox starts. To do this add the following lines to the bottom of the config file:</span><br /><span style="color: rgb(0, 0, 0);font-style: italic;">imgmount d /home/yourusername/.dosbox/lba.iso -t iso -fs iso</span><br /><span style="color: rgb(0, 0, 0);font-style: italic;">c:</span><br /><span style="color: rgb(0, 0, 0);font-style: italic;">cd relent</span><br /><span style="color: rgb(0, 0, 0);font-style: italic;">relent</span><br /><br /><span style="color: rgb(0, 0, 0);font-size:130%;"><span style="color: rgb(0, 0, 0);font-weight: bold;">4. Installing the Game</span></span><br /><span style="color: rgb(0, 0, 0)">Start DOSBox</span><br /><span style="color: rgb(0, 0, 0);font-family:courier new;">$ dosbox</span><br /><br /><span style="color: rgb(0, 0, 0)">From this point on run commands in the DOSBox window.</span><br /><br /><span style="color: rgb(0, 0, 0);font-weight: bold;">Install the Game</span><br /><span style="color: rgb(0, 0, 0);font-family: courier new;">Z:\> d:</span><br /><span style="color: rgb(0, 0, 0);font-family:courier new;">D:\> install</span><br /><br /><span style="color: rgb(0, 0, 0)">Choose to install to C drive</span><br /><br /><span style="color: rgb(0, 0, 0);font-weight: bold;">Configure the Game</span><br /><span style="color: rgb(0, 0, 0);font-family:courier new;">Z:\> c:</span><br /><span style="color: rgb(0, 0, 0);font-family:courier new;">C:\> cd relent</span><br /><span style="color: rgb(0, 0, 0);font-family:courier new;">C:\RELENT> setup</span><br /><br /><span style="color: rgb(0, 0, 0)">Set the following options:</span><br /><span style="color: rgb(0, 0, 0);font-style: italic;">> Music Sound Card Configuration</span><br /><span style="color: rgb(0, 0, 0);font-style: italic;">>> Sound Blaster 16 (OPL3)</span><br /><span style="color: rgb(0, 0, 0);font-style: italic;">>>> 220h</span><br /><span style="color: rgb(0, 0, 0);font-style: italic;">> FX Sound Card Configuration</span><br /><span style="color: rgb(0, 0, 0);font-style: italic;">>> Sound Blaster 16</span><br /><span style="color: rgb(0, 0, 0);font-style: italic;">>>> 220h</span><br /><span style="color: rgb(0, 0, 0);font-style: italic;">> Speech Configuration</span><br /><span style="color: rgb(0, 0, 0);font-style: italic;">>> Keep Speech Files on Hard Disk - YES</span><br /><span style="color: rgb(0, 0, 0);font-style: italic;">> Save Parameters</span><br /><span style="color: rgb(0, 0, 0);font-style: italic;">> Quit to DOS</span><br /><br /><span style="color: rgb(0, 0, 0)">Exit from DOSBox</span><br /><span style="color: rgb(0, 0, 0);font-family:courier new;">C:\RELENT> exit</span><br /><br /><span style="color: rgb(0, 0, 0);font-weight: bold;">Copy the Voice Files</span><br /><span style="color: rgb(0, 0, 0)">Back in the Linux terminal copy the voice files to the C drive folder.</span><br /><span style="color: rgb(0, 0, 0);font-family:courier new;">$ cp -R /media/cdrom/LBA/VOX /home/yourusername/.dosbox/cdrive/RELENT</span><br /><br /><span style="color: rgb(0, 0, 0);font-size:130%;"><span style="color: rgb(0, 0, 0);font-weight: bold;">6. Start the Game</span></span><br /><span style="color: rgb(0, 0, 0);font-family:courier new;">$ dosbox</span><br /><span style="color: rgb(0, 0, 0)">If you chose not to start the game on DOSBox startup then run the following in the DOSBox window.</span><br /><span style="color: rgb(0, 0, 0);font-family:courier new;">Z:\> c:</span><br /><span style="color: rgb(0, 0, 0);font-family:courier new;">C:\> cd relent</span><br /><span style="color: rgb(0, 0, 0);font-family:courier new;">C:\RELENT> relent</span><br /><br /><span style="color: rgb(0, 0, 0);font-style: italic;">Enjoy</span>greenarrowhttp://www.blogger.com/profile/06264757409706511516noreply@blogger.com0tag:blogger.com,1999:blog-7849499555071840363.post-45411433741914036042010-06-03T13:19:00.000-07:002010-06-03T14:30:12.295-07:00A while since progressIt's been quite a while since I last posted here. For the most part work on my RepRap has slowed a lot since the end of last year. Reasons for this seem to be: not having any outside in my new flat (except a large public park where I saw and drill on occasionally while, getting some odd looks), and Might as well blame it on moneygeddon too if that is still trendy.<br /><br />One of my biggest problems has been the generation one pic electronics I am still trying to use. While I am appreciative of the work that has gone into keeping the SNAP support in the current RepRap host, I have have spent many days getting things 'almost' working, then packing up and leaving it for a few more weeks while making no real long term progress.<br /><br />So today I decided to invest in some of Kimberly's Techzone boards. They will be much easier to debug and I will be able to work with all the bleeding edge techniques that I was denied with the PIC electronics.<br /><br />I have also tried to use my own Python SNAP stack for FFM printing with my machine, but there are a few deep issues especially in regards to performance regarding this stack that I have still not got around to fixing, and do not believe it is usable to FFM as a decent speed. It is still pretty handy for all other manner of uses for a Cartesian machine and for testing and I will be bringing it to the Generation 3 electronics when I receive them.<br /><br />I have plans to re-purpose my generation one electronics either on a RepRapped mini mill or a commercially purchased one (Sable 2015)greenarrowhttp://www.blogger.com/profile/06264757409706511516noreply@blogger.com0tag:blogger.com,1999:blog-7849499555071840363.post-52024635305641841622009-10-07T12:33:00.000-07:002009-10-07T12:40:47.879-07:00repstrap moving aboutIt's alive!<br /><br /><object type="application/x-shockwave-flash" width="640" height="360" data="http://www.flickr.com/apps/video/stewart.swf?v=71377" classid="clsid:D27CDB6E-AE6D-11cf-96B8-444553540000"> <param name="flashvars" value="intl_lang=en-us&photo_secret=dcd1c2fc6a&photo_id=3990276359"></param> <param name="movie" value="http://www.flickr.com/apps/video/stewart.swf?v=71377"></param> <param name="bgcolor" value="#000000"></param> <param name="allowFullScreen" value="true"></param><embed type="application/x-shockwave-flash" src="http://www.flickr.com/apps/video/stewart.swf?v=71377" bgcolor="#000000" allowfullscreen="true" flashvars="intl_lang=en-us&photo_secret=dcd1c2fc6a&photo_id=3990276359" height="360" width="640"></embed></object><br /><br />I am going to finish that Y axis motor bracket :)<br />The spanner is because the X carridge design relies on some off centre weight, which is normally my extruder that is currently broken.greenarrowhttp://www.blogger.com/profile/06264757409706511516noreply@blogger.com0tag:blogger.com,1999:blog-7849499555071840363.post-20427753593357084092009-10-07T12:22:00.000-07:002009-10-07T12:32:56.911-07:00Awesome picture of the night skyYou may have seen <a href="http://science.slashdot.org/story/09/09/29/0049214/The-Night-Sky-In-800-Million-Pixels?from=rss">this story on slashdot</a> but been a little annoyed when you couldn't just download a nice big image and instead had to look at it in some stupid flash or <a href="http://realis.mc/brunier/images/cielhd.jpg/zoom_view">js viewer</a>.<br /><br />I'm not going to upload any images but I might just leave <a href="http://codepad.org/BnqRZXFG">this here</a>.<br /><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="http://www.sergebrunier.com/gallerie/pleinciel/index-eng.html"><img style="margin: 0px auto 10px; display: block; text-align: center; cursor: pointer; width: 302px; height: 99px;" src="http://www.sergebrunier.com/gallerie/pleinciel/voie-lactee.jpg" alt="" border="0" /></a>greenarrowhttp://www.blogger.com/profile/06264757409706511516noreply@blogger.com0tag:blogger.com,1999:blog-7849499555071840363.post-12466783998841427922009-10-07T05:50:00.000-07:002009-10-07T06:24:35.821-07:00Making real use of Python in geditIf you are a fan of gedit, and a fan of Python like me then the chances are that you have tried out the gedit Python console plugin at some point. Years ago I tried it out but realised it was really aimed at plugin developers and not at people wanting a quick and easy way to manipulate data in the text editor.<br /><br />Last week I wrote a simple gedit plugin and so learned about the API and how to manipulate text in the editor. Even once I had learned about the API it still seemed far to complex to be usefull for quick data manipulation of an open file, so I decided to make a simple script that made things simpler, and makes the gedit Python console do what I wanted all along.<br /><br /><span style="font-weight: bold;">Get It</span><br /><br />Save <a href="http://codepad.org/8Rdow6yD">this script</a> as ~/.gnome2/gedit/plugins/doc.py<br />Now open up the Python console in gedit and type <tt>import doc</tt><br /><br /><span style="font-weight: bold;">Use It</span><br /><tt><br />import doc<br />d = doc.Doc(window)<br />d.set_lines( ['one', 'two', 'three'] )<br />d.append('\n')<br />d.append('four')<br />lines = d.get_lines()<br />lines.reverse()<br />d.set_lines(lines)<br /></tt><br />Now you can use regular expressions on you're open documents :)<br /><br /><span style="font-weight: bold;">Documentation</span><br /><br /><table><tbody><tr><td><br /></td><td width="100%"><span style="font-weight: bold;">doc.Doc:</span><br /><dl><dt><strong>__init__</strong>(self, window)</dt><dd><tt>Create Doc instance</tt></dd></dl><dl><dt><strong>append</strong>(self, text)</dt><dd><tt>Add text to the bottom of the document</tt></dd></dl><dl><dt><strong>clear</strong>(self)</dt><dd><tt>Clear the document</tt></dd></dl><dl><dt><strong>get_line</strong>(self)</dt><dd><tt>Return the contents of the line that the cursor is currently on</tt></dd></dl><dl><dt><strong>get_lines</strong>(self)</dt><dd><tt>Return a list containing all of the lines in the document</tt></dd></dl><dl><dt><strong>get_selection</strong>(self)</dt><dd><tt>Return the selected text</tt></dd></dl><dl><dt><strong>get_text</strong>(self)</dt><dd><tt>Return the full text of the document</tt></dd></dl><dl><dt><strong>set_lines</strong>(self, lines)</dt><dd><tt>Replace the current document with the lines in the supplied list</tt></dd></dl><dl><dt><strong>set_text</strong>(self, text)</dt><dd><tt>Set the full text of the document</tt></dd></dl></td></tr></tbody></table>greenarrowhttp://www.blogger.com/profile/06264757409706511516noreply@blogger.com0tag:blogger.com,1999:blog-7849499555071840363.post-15628156995600007582009-09-26T11:40:00.000-07:002009-09-26T12:02:51.915-07:00Bluetooth scanning experimentsThis was never supposed to be exclusively a RepRap blog, I've just never posted anything else on it before, so here goes.<br /><br />I moved into a new flat that is above a high street, and noticed that there were always a lot of bluetooth devices (phones) around when I looked in the Gnome bluetooth applet.<br /><br />I created a simple script that continually scans for devices and reads out people's bluetooth names out loud using <a href="http://www.cstr.ed.ac.uk/projects/festival/">festival</a>. The next day I broke my vow to never own a Twitter account after I saw how simple the Python <a href="http://code.google.com/p/python-twitter/">API</a> was to use, so now all the names are now posted <a href="http://twitter.com/bluehighstreet">on Twitter</a> too.<br /><br />Why? It's all rather pointless, I'm sure it's been done before, but it's an interesting experiment and emphasises the privacy concerns of having your phone continually shouting out "me me me" with a unique identification number (MAC) to anyone who wants to know. I also observed that many of the bluetooth names are actually just set to the phone make and model. It's probably not the best idea to have you're rather expensive phone advertising itself as "BlackBerry 8120" or "Nokia N95 8GB".<br /><br />You can see the full source <a href="http://codepad.org/l1ybCuOC">here</a>.<span style="display: block;" id="formatbar_Buttons"><span class="on down" style="display: block;" id="formatbar_CreateLink" title="Link" onmouseover="ButtonHoverOn(this);" onmouseout="ButtonHoverOff(this);" onmouseup="" onmousedown="CheckFormatting(event);FormatbarButton('richeditorframe', this, 8);ButtonMouseDown(this);"><img src="img/blank.gif" alt="Link" class="gl_link" border="0" /></span></span>greenarrowhttp://www.blogger.com/profile/06264757409706511516noreply@blogger.com2tag:blogger.com,1999:blog-7849499555071840363.post-17011753134124064862009-06-28T03:56:00.000-07:002009-06-28T05:48:23.042-07:00Spider GripMy mini Darwin design does not have enough space to put the Z axis motor in-line with one of the treaded rods, so from the beginning I had been thinking of placing the motor along one of the side rods. I have been trying to think of a good way of mounting the motor for a while now, then a few days ago I had the idea of making this 'spider grip' (it looks a bit like a four legged spider).<br /><br /><a href="http://www.flickr.com/photos/greenarrowdev/3667922128/" title="hpim1758.jpg by greenarrowstef, on Flickr"><img src="http://farm4.static.flickr.com/3361/3667922128_c30e92a22d.jpg" alt="hpim1758.jpg" height="460" width="500" /></a><br /><br />The 'legs' arch up before going to the 'body' to give some elasticity, so that when the screws are tightened the rod is held very firmly against the motor.<br /><br /><a href="http://www.flickr.com/photos/greenarrowdev/3667117667/" title="hpim1759.jpg by greenarrowstef, on Flickr"><img src="http://farm3.static.flickr.com/2427/3667117667_874c12f585.jpg" alt="hpim1759.jpg" height="500" width="475" /></a><br /><br />Here it is fitted to the machine. It gives a very firm grip, however it can be twisted fairly easily around the axis, but is firm enough to keep it in place. The only forces that will be applied to the motor when in operation are a liner force along the length of the chain, and a rotary force around the motor spindle, so no force should be present in the one direction that the motor can twist.<br /><br /><a href="http://www.flickr.com/photos/greenarrowdev/3667119751/" title="hpim1763.jpg by greenarrowstef, on Flickr"><img src="http://farm3.static.flickr.com/2555/3667119751_24ff1453f1.jpg" alt="hpim1763.jpg" height="500" width="379" /></a><br /><br />I've just put a load of closeup pictures of the machine onto <a href="http://www.flickr.com/photos/greenarrowdev/">my flickr page</a>.<br /><br /><a href="http://www.flickr.com/photos/greenarrowdev/3667929704/" title="hpim1768.jpg by greenarrowstef, on Flickr"><img src="http://farm3.static.flickr.com/2433/3667929704_a39edbf7da.jpg" alt="hpim1768.jpg" height="379" width="500" /></a><br /><br />Unfortunately I've just broken my extruder, but more about that next.greenarrowhttp://www.blogger.com/profile/06264757409706511516noreply@blogger.com0tag:blogger.com,1999:blog-7849499555071840363.post-74558135963481865752009-06-25T05:10:00.000-07:002009-06-30T05:40:52.658-07:00Broken extruderI broke my extruder!<br /><br />I have used my extruder with CAPA before and it has been reasonably reliable, though I was never able to get any filament (I just rolled some bits). I gave up on trying to get any and so I recently purchased some ABS.<br /><br />I put the ABS into the extruder, heated it up, and ran the last of the CAPA out. I turned the temperature up on the extruder, but was unable to get past 159 degrees. Eventually I decided that the temperature was not going to get any higher so I tried to run the ABS through anyway.<br /><br />In the past the motor has stalled quite easily at low speeds when the extruder is not hot enough, but this time it didn't stall and instead pushed the heater barrel out of the PTFE rod. Presumably this is because I have never had the extruder this hot before.<br /><br /><a href="http://www.flickr.com/photos/greenarrowdev/3668266448/" title="HPIM1750.JPG by greenarrowstef, on Flickr"><img src="http://farm3.static.flickr.com/2427/3668266448_a109f39021.jpg" alt="HPIM1750.JPG" height="292" width="500" /></a><br /><br /><br /><a href="http://www.flickr.com/photos/greenarrowdev/3667462771/" title="HPIM1752.JPG by greenarrowstef, on Flickr"><img src="http://farm3.static.flickr.com/2424/3667462771_41fa3af3dd.jpg" alt="HPIM1752.JPG" height="327" width="500" /></a><br /><br />I ordered some PTFE rod, some brass bolts, nichrome, thermistors, thicker cable (for connecting heater to board), drill bits and an M6 tap. This should be enough to make a few experimental barrels, although I'm not yet sure how I'm going to do this without a proper pillar drill or lathe.greenarrowhttp://www.blogger.com/profile/06264757409706511516noreply@blogger.com0tag:blogger.com,1999:blog-7849499555071840363.post-8444077642031025442009-05-18T15:11:00.000-07:002009-05-19T01:21:27.037-07:00CAPA fixes everything!<a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="http://farm3.static.flickr.com/2237/3544127722_327e5a14d3_b_d.jpg"><img style="margin: 0px auto 10px; display: block; text-align: center; cursor: pointer; width: 275px; height: 363px;" src="http://farm3.static.flickr.com/2237/3544127722_327e5a14d3_b_d.jpg" alt="" border="0" /></a><br />I've made a bit more progress with my mini Darwin. I now have an X axis with the extruder mounted on it, as well as a more or less complete Z axis. When pushing the extruder around it moves very smoothly, and with very little force so I'm hoping to get some pretty decent print speeds and much better quality than my Lego RepStrap. My idea with this RepStrap is to put in the least amount of required effort to get the thing of the ground, I'm not really designing the thing to last. Then once it is printing I can replace the lower quality pieces with new printed parts!<br /><br /><br /><span style="font-weight: bold;">A quick note about drills</span><br />I did not use a pillar drill for my corner blocks, I just used an electric hand drill and a set square. The holes are more or less straight but the imperfections have caused me a lot of problems. My machine is actually a parallelogram rather than a square, but as long the the axis slide rods are parallel then this does not matter too much. I would advise anyone without a pillar drill to try and find one they can use, as the time you spend finding one will be much less that the amount of time you will spend trying the get everything straight afterwards!<br /><br /><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="http://farm3.static.flickr.com/2078/3544127738_6faf6a096e_b_d.jpg"><img style="margin: 0px auto 10px; display: block; text-align: center; cursor: pointer; width: 275px; height: 361px;" src="http://farm3.static.flickr.com/2078/3544127738_6faf6a096e_b_d.jpg" alt="" border="0" /></a><br />I had not realised how much the extruder would overhang on the X axis, so my idea of having a X carriage just using skate bearings on top was not going to work. A bit of CAPA moulding later and I had a nice part that holds a third bearing underneath the carriage, rolling along the underside of the steel rod. The piece was bent a little before it set so that it is sprung firmly against the rod (CAPA is very 'springy') keeping the X carriage very firmly against the rod.<br /><br /><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="http://farm4.static.flickr.com/3099/3544127746_2f555e422c_b_d.jpg"><img style="margin: 0px auto 10px; display: block; text-align: center; cursor: pointer; width: 364px; height: 275px;" src="http://farm4.static.flickr.com/3099/3544127746_2f555e422c_b_d.jpg" alt="" border="0" /></a><br />I made these CAPA brackets to hold the nuts and used just two screws in each of them to allow a little play, but only when tensioned against the twisting of the CAPA.<br /><br /><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="http://farm3.static.flickr.com/2009/3544127780_4d4c2c05d9_b_d.jpg"><img style="margin: 0px auto 10px; display: block; text-align: center; cursor: pointer; width: 365px; height: 275px;" src="http://farm3.static.flickr.com/2009/3544127780_4d4c2c05d9_b_d.jpg" alt="" border="0" /></a><br />Building a jig first makes making parts from CAPA much easier. These are bearing blocks for the Y axis using 608 skate bearings. They may not look precise, but the three holes are, and that is all that matters :)<br /><br />Now I'm just waiting for my gears and chain to arrive, but in the meantime I can still make my X, Y & Z motor mounts. Time for some more CAPA I think.greenarrowhttp://www.blogger.com/profile/06264757409706511516noreply@blogger.com0tag:blogger.com,1999:blog-7849499555071840363.post-34990459562790201282009-05-11T11:32:00.001-07:002009-05-11T11:51:21.501-07:00Gears and chainI have decided to use this <a href="http://www.rapidonline.com/Educational-Products/Graphics-Art-Design/Model-Accessories/Ladder-chain/10535/kw/chain"><span style="text-decoration: underline;">chain</span></a> with these <a href="http://www.rapidonline.com/Educational-Products/Graphics-Art-Design/Model-Accessories/Polythene-gears/34864/kw/37-0190">gears</a>,<br /><br />I will use the 15mm gears for the X and Y axes and the 40mm ones for the Z axis. For my mini Darwin I will need: Y axis - 510mm x 2; X axis - 564mm; Z axis - 972mm. This gives a total of 2556mm so I will need to order 3m.<br /><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="http://www.rapidonline.com/netalogue/photos/06065001.jpg"><img style="margin: 0px auto 10px; display: block; text-align: center; cursor: pointer; width: 200px; height: 200px;" src="http://www.rapidonline.com/netalogue/photos/06065001.jpg" alt="" border="0" /></a><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="http://www.rapidonline.com/netalogue/photos/37019001.jpg"><img style="margin: 0px auto 10px; display: block; text-align: center; cursor: pointer; width: 200px; height: 200px;" src="http://www.rapidonline.com/netalogue/photos/37019001.jpg" alt="" border="0" /></a>This works out quite extensive at £30.25 for all the chain and gears but I will have plenty of gears left over (they come in a large pack) and will be happy to send any to anyone in the UK who wants any.<br /><br />The motors I have are 200 steps per revolution, using a 15mm gear the axis will move 47.115mm per revolution. This gives an axis resolution of 0.24mm which I will be perfectly happy with.greenarrowhttp://www.blogger.com/profile/06264757409706511516noreply@blogger.com0tag:blogger.com,1999:blog-7849499555071840363.post-79782661031250915282009-05-10T14:23:00.000-07:002009-05-10T14:50:58.633-07:00Mini DarwinI received my 20 300mm threaded steel rods with lots of nuts and washers so I set about making some corner brackets to hold them all together. I don't have a pillar drill so I just had to drill holes with an electric hand drill and a set square. This worked reasonable well but the holes were very rarely at perfect right angles. To 'fix' this I used a reamer to enlarge the holes, allowing the steel rods to line up straightly. This would not work in the standard Darwin design using un-threaded rods and grub screws. However with this design it does not matter if the hole is a bit bigger, as long as the blocks themselves have right angle sides then the rods will line up when the nuts and washers are tightened. While not elegant, it works.<br /><br /><div style="text-align: center;"><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjXxPa7BQlggFATXc7b0D0cIhk7-tqIoaYjf_MPD8xRzPL7Yu5mx7t6ojC62KwXPuanboJIVrMZZXCuqLZc3_Wheqk8yxFudUcuFBE1KnYpyIdU6FXif5XH8YM_yGTyQu1GivlGQgrf5Hs/s1600-h/hpim1658.jpg"><img style="margin: 0px auto 10px; display: block; text-align: center; cursor: pointer; width: 320px; height: 242px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjXxPa7BQlggFATXc7b0D0cIhk7-tqIoaYjf_MPD8xRzPL7Yu5mx7t6ojC62KwXPuanboJIVrMZZXCuqLZc3_Wheqk8yxFudUcuFBE1KnYpyIdU6FXif5XH8YM_yGTyQu1GivlGQgrf5Hs/s320/hpim1658.jpg" alt="" id="BLOGGER_PHOTO_ID_5334309722361747570" border="0" /></a><span style="font-style: italic;">A mitre box is essential</span><br /><br /></div>I also used soft wood, again because of the threaded rods, the blocks become stronger when they are assembled.<br /><br /><br /><div style="text-align: center;"><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjiNGm540VvMU0iozrBCo6dvIpWlopB9MwfddtO-_Rsr01N2tseDW_3rqdWpFxumoA8ucYFS7eOCov2hWPdhi0FlGC_EI9doqQgDrX12h6MsBTCrJmhKWfJmLYGFGNP2YlbpIXl3B4vG5A/s1600-h/hpim1649.jpg"><img style="margin: 0px auto 10px; display: block; text-align: center; cursor: pointer; width: 320px; height: 242px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjiNGm540VvMU0iozrBCo6dvIpWlopB9MwfddtO-_Rsr01N2tseDW_3rqdWpFxumoA8ucYFS7eOCov2hWPdhi0FlGC_EI9doqQgDrX12h6MsBTCrJmhKWfJmLYGFGNP2YlbpIXl3B4vG5A/s320/hpim1649.jpg" alt="" id="BLOGGER_PHOTO_ID_5334309520394768914" border="0" /></a><span style="font-style: italic;">Four blocks ready for drilling</span><br /></div><br /><br /><div style="text-align: center;"><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiM85VQmVxfsK1V7crABtEJtxPoCHIAiWgm_eNNf5yJ1IKJHFmXceKAm41OQLOqD3z1R8UqBvjKmqfD6YzsVfgfJSj0JHgOTRx1YBvzEDgXtsNHm5J_d6VIaC8yX_HXnkxjj9Is0f6vzvU/s1600-h/hpim1659.rotated.jpg"><img style="margin: 0px auto 10px; display: block; text-align: center; cursor: pointer; width: 242px; height: 320px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiM85VQmVxfsK1V7crABtEJtxPoCHIAiWgm_eNNf5yJ1IKJHFmXceKAm41OQLOqD3z1R8UqBvjKmqfD6YzsVfgfJSj0JHgOTRx1YBvzEDgXtsNHm5J_d6VIaC8yX_HXnkxjj9Is0f6vzvU/s320/hpim1659.rotated.jpg" alt="" id="BLOGGER_PHOTO_ID_5334310336192864834" border="0" /></a><span style="font-style: italic;">The assembled frame</span><br /><br /></div>The Y axis moves very nicely on the shrink-wrap covered threaded rod. Next I need to get some chain or belt, and make the Z axis and print table.<br /><br />I think 300mm rods may have been a little small and will give a very small [but usable] print area. I probably would have been able to get away with some smaller motors too as the skate bearing axes require very little force to move.greenarrowhttp://www.blogger.com/profile/06264757409706511516noreply@blogger.com0tag:blogger.com,1999:blog-7849499555071840363.post-11489251671932150772009-05-07T14:53:00.000-07:002009-05-07T14:55:13.374-07:00Spanner Spin<object type="application/x-shockwave-flash" width="300" height="400" data="http://www.flickr.com/apps/video/stewart.swf?v=71377" classid="clsid:D27CDB6E-AE6D-11cf-96B8-444553540000"> <param name="flashvars" value="intl_lang=en-us&photo_secret=1e7224e8de&photo_id=3511540788"></param> <param name="movie" value="http://www.flickr.com/apps/video/stewart.swf?v=71377"></param> <param name="bgcolor" value="#000000"></param> <param name="allowFullScreen" value="true"></param><embed type="application/x-shockwave-flash" src="http://www.flickr.com/apps/video/stewart.swf?v=71377" bgcolor="#000000" allowfullscreen="true" flashvars="intl_lang=en-us&photo_secret=1e7224e8de&photo_id=3511540788" height="400" width="300"></embed></object><br /><span style="font-style: italic;">ultimate stepper testing - stepper motor spins spanner!</span>greenarrowhttp://www.blogger.com/profile/06264757409706511516noreply@blogger.com0tag:blogger.com,1999:blog-7849499555071840363.post-59082196312641224952009-05-07T13:20:00.000-07:002009-05-07T14:55:48.832-07:00New MotorsToday I tried out my <a href="http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=170326692169">new motors from eBay</a><br /><br />Up until now I have been using a hacked around firmware in which I had changed the coil sequence to give greater torque when using tin-can unipolar stepper motors (by ensuring two coils were always powered at any given moment). Now I'm using some proper bipolar motors so I dug out my old JDM PIC programmer and flashed the chips with the last standard firmware.<br /><br />I wired the motor coils up in series to give a coil resistance of 12.4Ohms per phase and a maximum current of 970mA. Well within the capabilities of the driver IC. The 'Rated Voltage' in the datasheet works out at setting the PWM duty to around 72% but the motors seem to run happily full power without getting hot.<br /><br />At full power I can run the motor at up to 240 (PIC speed byte) with no load before the motor starts missing steps, and at 72% power up to 235<br /><br />I haven't tested them for real on a machine but so far I am very impressed with these motors as they cost only £9.26 each when buying four + £11.97 postage<br /><br />I tested all of this from a Python console:<br /><br /><pre class="alt2" dir="ltr" style="border: 1px inset ; margin: 0px; padding: 6px; overflow: auto; text-align: left;">import reprap<br />reprap.openSerial('/dev/ttyUSB0', 19200, 60)<br />reprap.cartesian.x.active = True<br />reprap.cartesian.setPower(72)<br />reprap.cartesian.x.forward(235)<br /></pre>greenarrowhttp://www.blogger.com/profile/06264757409706511516noreply@blogger.com0tag:blogger.com,1999:blog-7849499555071840363.post-52934394682331448582009-05-06T09:39:00.000-07:002009-05-06T11:38:36.587-07:00No more Lego RepStrapI've decided to call it a day with my Lego based RepStrap (but not on making a RepStrap). It has been interesting to experiment with but I ran into too many problems and have decided that a more substantial steel-based solution is in order. The machine has been sitting there for a few months not doing anything now, this is the short story of my change in direction over the last few days after being inspired by some recent blog posts.<br /><br /><br /><div style="text-align: center;"><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhAMS4xhiSXPQcvN4LeFr8QBzQmXqGTtSdpLrGEe0Kxpz7ReqQb3HRZDEn9omuRxwDllM9cN57Egz3vwGQ_BEo6M2G81rkato8BZCnR08jhyuDr7eefihzsoN_Quia-lcOCRQlOlMR4JE4/s1600-h/hpim1637.jpg"><img style="margin: 0px auto 10px; display: block; text-align: center; cursor: pointer; width: 320px; height: 242px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhAMS4xhiSXPQcvN4LeFr8QBzQmXqGTtSdpLrGEe0Kxpz7ReqQb3HRZDEn9omuRxwDllM9cN57Egz3vwGQ_BEo6M2G81rkato8BZCnR08jhyuDr7eefihzsoN_Quia-lcOCRQlOlMR4JE4/s320/hpim1637.jpg" alt="" id="BLOGGER_PHOTO_ID_5332775208503267634" border="0" /></a><span style="font-style: italic;">My decomissioned Lego RepStrap</span><br /></div><br /><br /><div style="text-align: center;"><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhixXoz8Zagb8XpuDYkDUi6BU_hUer0nFTFPXbZa84X9v717yTl2TKNjwG8Jw35KoOOE_pMryThyvoRmX-Mqa9C3bwvpNBBaz8g8NVr_7_h7ZFb5gvWQX-NjqTdQZcX4Jmu0AeiiRQ8UCk/s1600-h/hpim1642.jpg"><img style="margin: 0px auto 10px; display: block; text-align: center; cursor: pointer; width: 320px; height: 242px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhixXoz8Zagb8XpuDYkDUi6BU_hUer0nFTFPXbZa84X9v717yTl2TKNjwG8Jw35KoOOE_pMryThyvoRmX-Mqa9C3bwvpNBBaz8g8NVr_7_h7ZFb5gvWQX-NjqTdQZcX4Jmu0AeiiRQ8UCk/s320/hpim1642.jpg" alt="" id="BLOGGER_PHOTO_ID_5332775492047245058" border="0" /></a><span style="font-style: italic;">The best model it ever produced</span><br /></div><br /><br />First I decided to give up on screw driven axes as they are very so slow to move and make printing painfully slow. With this in mind I ordered some new more powerful motors to drive the axes directly. I received my new stepper motors today. I got four NEMA 23s from Astrosyn for £49 including postage.<br /><br /><div style="text-align: center;"><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjibY00e2MZ7TXMdnlHzY276GCEQImMTdYJ7OS7ndG1xAQvd3Cj_KEzP5VTaDLg6F6vwKQy4zNlEVn8iPE0Ew0LPhF0FOI0CETNki-NDfRcEfCjgi0lQ47wDubvCr66ephY3m4cuRbvy0w/s1600-h/hpim1629.jpg"><img style="margin: 0px auto 10px; display: block; text-align: center; cursor: pointer; width: 320px; height: 242px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjibY00e2MZ7TXMdnlHzY276GCEQImMTdYJ7OS7ndG1xAQvd3Cj_KEzP5VTaDLg6F6vwKQy4zNlEVn8iPE0Ew0LPhF0FOI0CETNki-NDfRcEfCjgi0lQ47wDubvCr66ephY3m4cuRbvy0w/s320/hpim1629.jpg" alt="" id="BLOGGER_PHOTO_ID_5332774598558169666" border="0" /></a><span style="font-style: italic;">New motors!</span><br /></div><br />They are not the most amazing spec motors but I think they should be perfectly sufficient.<br /><br />I also bought some 608 skate bearings the other day with the intention of using them to make a new Z axis for my Lego RepStrap. I started playing around with them, and tried bolting two up close together like James did <a href="http://builders.reprap.org/2009/03/skate-bearings-and-bike-chain.html">here</a> and running it along another [threaded] steel rod. I was impressed that it even ran pretty smoothly even along a threaded rod. I then tired covering a rod in heat-shrink plastic to make it even smoother.<br /><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEj0Tlj-6ankcNp2qZLVs_YDH4z9UPKi3IIbjmlDeL4KgcdiO1zswE5OpY6h4NbqfprP_tk1rXTVSzHvaVxXmL7yJEyLqtAmHABwyvDzoEIsvfM4_UXRYqW-W6Fi27m6OxqD6R_Kly6DW0o/s1600-h/hpim1634.jpg"><img style="margin: 0px auto 10px; display: block; text-align: center; cursor: pointer; width: 320px; height: 242px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEj0Tlj-6ankcNp2qZLVs_YDH4z9UPKi3IIbjmlDeL4KgcdiO1zswE5OpY6h4NbqfprP_tk1rXTVSzHvaVxXmL7yJEyLqtAmHABwyvDzoEIsvfM4_UXRYqW-W6Fi27m6OxqD6R_Kly6DW0o/s320/hpim1634.jpg" alt="" id="BLOGGER_PHOTO_ID_5332774885676981986" border="0" /></a><br /><br />This gave a very smooth run, and also moved incredibly silently due to the dampening from the thin layer of heat-shrink plastic. A quiet machine is an important goal of mine [this is why I also plan to move to a stepper driven pinch-wheel extruder].<br /><br />At this point I became decided that abandoning my Lego RepStrap was in order and started looking around for other parts.<br /><br />I saw the post <a href="http://builders.reprap.org/2009/04/ikea-design.html">Ikea Design</a> and remembered that I had seen the very same chain and gears available from Rapid Electronics.<br /><br />I found a company selling M8 300mm threaded steel rods <a href="http://stores.ebay.co.uk/FixItAtHomeUK">on eBay</a> for<span class="vi-is1-prcp"><span> £3.37 for five + postage and was unable to resist the temptation of nicely pre-cut rods. I ordered 20 M8 300mm rods today and a whole load of nuts and washers.<br /><br />My plan now is to make some corner pieces from wood and construct the steel frame, then put the motors, gears and chain on. The four rods that have skate-bearing runners sliding along them will be covered in heat-shrink plastic.<br /><br /></span></span><div style="text-align: center;"><span class="vi-is1-prcp"><span><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiuLD9QH-GmfSONxmqT84GVzPX_kJxp3RTymU_G8x2rUARSI_De_oCDZj4fS2BsQOleCkC2Qvgfq7sEi-Y2B_liuxAHFi15YszrGzuN_db7RYnvvEW4bmw7g3mQdbYW9pxJBr9GuX00Afk/s1600-h/hpim1646cut.jpg"><img style="margin: 0px auto 10px; display: block; text-align: center; cursor: pointer; width: 295px; height: 320px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiuLD9QH-GmfSONxmqT84GVzPX_kJxp3RTymU_G8x2rUARSI_De_oCDZj4fS2BsQOleCkC2Qvgfq7sEi-Y2B_liuxAHFi15YszrGzuN_db7RYnvvEW4bmw7g3mQdbYW9pxJBr9GuX00Afk/s320/hpim1646cut.jpg" alt="" id="BLOGGER_PHOTO_ID_5332776381988637618" border="0" /></a><span style="font-style: italic;">Quick sketch of my new design</span></span></span><br /></div><span class="vi-is1-prcp"><span><br />I am also thinking of trying and modify my generation one PIC electronics to run a stepper driven pinch-wheel extruder.<br /></span></span>greenarrowhttp://www.blogger.com/profile/06264757409706511516noreply@blogger.com0tag:blogger.com,1999:blog-7849499555071840363.post-35315686347174943032009-05-06T09:01:00.000-07:002009-05-06T09:05:19.501-07:00First Post<a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="http://www.roofthatch.com/shed1.jpg"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 402px; height: 469px;" src="http://www.roofthatch.com/shed1.jpg" border="0" alt="" /></a><br />This is not really my shed<br /><br />Ok in my current house I don't actually have a shed, but if I did have one I would be using it. I used to have a good shed in my last house but decided that choosing a place to rent on the quality of the shed is probably not the best idea.greenarrowhttp://www.blogger.com/profile/06264757409706511516noreply@blogger.com1