tag:blogger.com,1999:blog-17989704779965195102024-02-18T22:24:49.897-05:00Rocket MoonlightingOpen source confessions of an "Old Space" engineer.RMhttp://www.blogger.com/profile/14180745747728028165noreply@blogger.comBlogger84125tag:blogger.com,1999:blog-1798970477996519510.post-7362536316093971892016-04-07T19:25:00.003-04:002016-04-07T19:25:44.264-04:00Space Access 2016Hope to see everyone at Space Access over the next few days in Phoenix!<br />
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http://space-access.org/updates/sa16info.htmlRMhttp://www.blogger.com/profile/14180745747728028165noreply@blogger.com0tag:blogger.com,1999:blog-1798970477996519510.post-56729471822869459352016-03-19T13:43:00.002-04:002016-03-19T13:43:54.739-04:00New Digs, New GigI'm now at Ursa Major Technologies! <br />
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Check us out at:<br />
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<a href="http://www.ursamajortechnologies.com/">http://www.ursamajortechnologies.com/</a><br />
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and Instagram: <a href="https://www.instagram.com/ursamajortechnologies/">https://www.instagram.com/ursamajortechnologies/</a>RMhttp://www.blogger.com/profile/14180745747728028165noreply@blogger.com2tag:blogger.com,1999:blog-1798970477996519510.post-83603370826769029272015-05-02T23:55:00.002-04:002015-05-02T23:55:44.891-04:00Printing 5000 Pounds<div class="separator" style="clear: both; text-align: center;">
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A few years ago, I designed a regen cooled thrust chamber in the 5000 pound thrust class. Lawrence Livermore National Lab printed the design shown below and I outfitted it for testing.<br />
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<a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiLvMFtoMGgO_L5pE7FQ2XOAHjKlK4GC9wobzq8J8ZIaTMOVo3ueoTplb_EDk6Z4XEBTajd2fTA2f4GIXVDe_CyfI5IL8EXaWhDHaXX5lD3RUohC-GQg0CKPxa7quLcrBC2WsJAPph8ivw/s1600/DSC_0240+-+Copy.JPG" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiLvMFtoMGgO_L5pE7FQ2XOAHjKlK4GC9wobzq8J8ZIaTMOVo3ueoTplb_EDk6Z4XEBTajd2fTA2f4GIXVDe_CyfI5IL8EXaWhDHaXX5lD3RUohC-GQg0CKPxa7quLcrBC2WsJAPph8ivw/s1600/DSC_0240+-+Copy.JPG" height="212" width="320" /></a></div>
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<a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiIFY5Q4LdrwHxdDIIJ9QM9vvhuKeiNunzmYqv5rninRbtJSMHQP1UPsyePUfj3pGh8Skn-GZiTIEe-Od9ckgy-sE_a-j9puTBKlGEtoet2tQixKh0DPz1Yqv8CweBJtETR4cb2tBu8Tj4/s1600/pr56-1.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiIFY5Q4LdrwHxdDIIJ9QM9vvhuKeiNunzmYqv5rninRbtJSMHQP1UPsyePUfj3pGh8Skn-GZiTIEe-Od9ckgy-sE_a-j9puTBKlGEtoet2tQixKh0DPz1Yqv8CweBJtETR4cb2tBu8Tj4/s1600/pr56-1.jpg" height="247" width="320" /></a></div>
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You can check out additional photos here: <br />
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<a href="https://manufacturing.llnl.gov/additive-manufacturing/metal-additive-manufacturing">https://manufacturing.llnl.gov/additive-manufacturing/metal-additive-manufacturing</a><br />
<br />RMhttp://www.blogger.com/profile/14180745747728028165noreply@blogger.com1tag:blogger.com,1999:blog-1798970477996519510.post-20229150383212182782015-02-11T22:23:00.000-05:002015-02-21T14:49:42.861-05:00PR56 Igniter Open SourceJust a note that a few months back I posted "<a href="http://www.rocketmoonlighting.com/projects/pr56-igniter">the source</a>" for the <a href="http://rocketmoonlighting.blogspot.com/2013/08/blue-flame.html">PR56 igniter</a> that I've tested with GOX/kerosene.<br />
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There is a dimensioned <a href="https://docs.google.com/a/rocketmoonlighting.com/viewer?a=v&pid=sites&srcid=cm9ja2V0bW9vbmxpZ2h0aW5nLmNvbXxob21lfGd4OjRkOWQwYWNhY2YxODUwOWI">drawing</a> of the igniter body as well as a <a href="https://docs.google.com/a/rocketmoonlighting.com/viewer?a=v&pid=sites&srcid=cm9ja2V0bW9vbmxpZ2h0aW5nLmNvbXxob21lfGd4OjNkNjliM2ZjYzY5NjhhMmI">detailed write-up</a> that includes parts lists and operational notes. If you make one or use it as inspiration, I'd love to hear about it via email or comment.<br />
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I'm planning on revitalizing the blog over the next few weeks, so stay tuned.RMhttp://www.blogger.com/profile/14180745747728028165noreply@blogger.com3tag:blogger.com,1999:blog-1798970477996519510.post-38442024478752267012014-06-23T23:27:00.000-04:002014-06-24T10:15:08.517-04:00A bigger valveHere is a larger version of an actuated valve assembly. The<a href="http://rocketmoonlighting.blogspot.com/2013/02/more-valves.html"> first version</a> is based around a 1/4" Swagelok valve (SS-4P4T). This version mates a 3/8" SwageLok 1/4 turn plug valve (SS-6P6T or B-6P6T) to a Hitec Standard size servo.<br />
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<a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgGo9agFK1RLOfA3o537wLdr06H1S5WVqNjBDcuwUum1EMSSjC26XmDhpZi734rSio2-dd5ZhyxpSs53u5ECU9kzCWpwklLO3R7ILR5Il1jZj6EXrnC5lqOxirHgNCxKf3UAAjQRC0DCf0/s1600/photo+2+(2).JPG" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgGo9agFK1RLOfA3o537wLdr06H1S5WVqNjBDcuwUum1EMSSjC26XmDhpZi734rSio2-dd5ZhyxpSs53u5ECU9kzCWpwklLO3R7ILR5Il1jZj6EXrnC5lqOxirHgNCxKf3UAAjQRC0DCf0/s1600/photo+2+(2).JPG" height="240" width="320" /></a></div>
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There are two printed parts:<br />
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Shaft Coupler - http://shpws.me/r4U6<br />
Yoke - http://shpws.me/r4kM<br />
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These are the fasteners needed:<br />
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<span style="background-color: white; font-family: inherit; font-size: 13.63636302947998px; line-height: 24px;">qty 4 8-32 x 1/2"" Socket Head Cap Screw, McMaster-Carr 92196A194 </span><br />
<span style="background-color: white; font-family: inherit; font-size: 13.63636302947998px; line-height: 24px;">qty 4 #8 Flat Washer, McMaster-Carr 96659A103</span><br />
<span style="background-color: white; font-family: inherit; font-size: 13.63636302947998px; line-height: 24px;">qty 2 4-40 x 1.75" Socket Head Cap Screw, McMaster-Carr 92185A128 </span><br />
<span style="background-color: white; font-family: inherit; font-size: 13.63636302947998px; line-height: 24px;">qty 2 #4 Flat Washer, McMaster-Carr 96659A101 </span>RMhttp://www.blogger.com/profile/14180745747728028165noreply@blogger.com1tag:blogger.com,1999:blog-1798970477996519510.post-59459143281503165912013-11-27T18:54:00.002-05:002013-11-27T18:54:31.971-05:00Testing the New Chambers<div class="separator" style="clear: both; text-align: center;">
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Just a quick note that testing is proceeding with the new Printed (3D printing, DMLS, additive manufatured) chambers. The cobalt alloy turns an interesting green color when it gets warm.RMhttp://www.blogger.com/profile/14180745747728028165noreply@blogger.com2tag:blogger.com,1999:blog-1798970477996519510.post-65056577697480304102013-09-30T00:44:00.002-04:002013-09-30T00:44:30.495-04:00Seeing TripleNew additively manufactured regen chambers<br />
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<a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjNM6DAJQDgCFuLSqDzSRLwgQAflFjhwclyBC9r7H2hIfhNz1oeG-viS1IAAIvV3Arz5k4-EA4cSliVVlrOBVmPZ-6LG4JJ8taLkaE4ipfTsN0NQzw4ESZWuIbfsxIL8Q4YQJRtSfyyhaw/s1600/photo+1+(2).JPG" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="320" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjNM6DAJQDgCFuLSqDzSRLwgQAflFjhwclyBC9r7H2hIfhNz1oeG-viS1IAAIvV3Arz5k4-EA4cSliVVlrOBVmPZ-6LG4JJ8taLkaE4ipfTsN0NQzw4ESZWuIbfsxIL8Q4YQJRtSfyyhaw/s320/photo+1+(2).JPG" width="240" /></a></div>
<br />RMhttp://www.blogger.com/profile/14180745747728028165noreply@blogger.com3tag:blogger.com,1999:blog-1798970477996519510.post-6222527463532155802013-08-18T16:12:00.002-04:002013-08-18T16:12:59.730-04:00Blue FlameIts been quite a while since my last post. Things have been busy and I'm working several nifty projects. I wanted to share a picture of a new igniter that I've made for a new project. It's designed to run on GOX/Kerosene and works well so far.<br />
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<a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhzY2MtG6DrCc5JCrxC7S96tI_fYJgb9kFWnwwtDCNlZ1Gc5x9kGbizl0koEK1w66foMX0hx6aMtFNZN63bHMXHhqD1pNT7YD6VSsYOKEoVvEgU4die5tGVWI-x3oSol7woBOkHsQve9wA/s1600/DSC_0125.JPG" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="169" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhzY2MtG6DrCc5JCrxC7S96tI_fYJgb9kFWnwwtDCNlZ1Gc5x9kGbizl0koEK1w66foMX0hx6aMtFNZN63bHMXHhqD1pNT7YD6VSsYOKEoVvEgU4die5tGVWI-x3oSol7woBOkHsQve9wA/s320/DSC_0125.JPG" width="320" /></a></div>
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RMhttp://www.blogger.com/profile/14180745747728028165noreply@blogger.com0tag:blogger.com,1999:blog-1798970477996519510.post-81185255015139232072013-03-09T15:30:00.001-05:002013-03-09T15:30:19.728-05:00Printed WidgetsI'm finding that 3D Printed parts are pretty handing for custom brackets and widgets. I'm currently working on a new chamber project and needed a mounting bracket for it. The part took me about 30 minutes to design and costs ~$15.<br />
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<a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEicMHVrWO26KT1cTSGYesvkEHdBoOLIe2FxIKeDUvud29jynfHheQGGzDSAwRpKunEFqRDKq4L8jxY83DyhrLVAZVzElKphg5Z7pRhgIQV3bTx8l_3fuvR7Sk67cHU88mgMUw9TYxL2PkE/s1600/photo+1.JPG" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="320" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEicMHVrWO26KT1cTSGYesvkEHdBoOLIe2FxIKeDUvud29jynfHheQGGzDSAwRpKunEFqRDKq4L8jxY83DyhrLVAZVzElKphg5Z7pRhgIQV3bTx8l_3fuvR7Sk67cHU88mgMUw9TYxL2PkE/s320/photo+1.JPG" width="240" /></a></div>
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<a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEh8wf0EKYmVwd-ag1UcwU-XLCxZd0k_bMAvwRNYOGEFLBpV_kvjxRcZ3ofkKPBZemSS2YZYjCNLCfmx5cXVf_Avg9I1Nb7R17VRZXcsTELSiESBmZ4jNBHJyQXBvYHoObqVTZTTJTIKZ-Q/s1600/photo+2.JPG" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="320" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEh8wf0EKYmVwd-ag1UcwU-XLCxZd0k_bMAvwRNYOGEFLBpV_kvjxRcZ3ofkKPBZemSS2YZYjCNLCfmx5cXVf_Avg9I1Nb7R17VRZXcsTELSiESBmZ4jNBHJyQXBvYHoObqVTZTTJTIKZ-Q/s320/photo+2.JPG" width="240" /></a></div>
<br />RMhttp://www.blogger.com/profile/14180745747728028165noreply@blogger.com2tag:blogger.com,1999:blog-1798970477996519510.post-7600539465734699602013-02-20T23:28:00.000-05:002013-02-20T23:28:20.184-05:00DMLS Chamber Version 2Here are the specs for the redesigned version of the DMLS chamber. This project pending interest and resources. Drop me a line if you would be interested in supporting a project like this.<br />
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<br />RMhttp://www.blogger.com/profile/14180745747728028165noreply@blogger.com5tag:blogger.com,1999:blog-1798970477996519510.post-90355772385389953872013-02-05T23:31:00.001-05:002013-02-05T23:33:13.477-05:00More ValvesI've been doing quite a bit of parts with Shapeways lately both flow models and functional parts. One of the latest is a rework of my <a href="http://www.rocketmoonlighting.com/valves">servo actuated plug valve</a>.<br />
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<a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEh9rcGICp-b9_VNa27FenVe0MvHmVeCtkjZ3EESGvb7uAP7L8306m99BAq8PK0H0adMrHHLtTQrxdN8IbQD3ulQX-fyfALFxkRUcuh5oHC1neHGhUf8f82CRNDk1RsPO2NXLY6X13yhi88/s1600/photo+(3)+(1).JPG" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="240" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEh9rcGICp-b9_VNa27FenVe0MvHmVeCtkjZ3EESGvb7uAP7L8306m99BAq8PK0H0adMrHHLtTQrxdN8IbQD3ulQX-fyfALFxkRUcuh5oHC1neHGhUf8f82CRNDk1RsPO2NXLY6X13yhi88/s320/photo+(3)+(1).JPG" width="320" /></a></div>
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Two parts allow a Swage-Lok SS-4P4T valve to be actuated by a Hitec servo - I recommend a high torque metal gear model like the HS-7954SH. The only other hardware required are (you'll need taps to clean up the threads in the nylon):<br />
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qty 4 8-32 x 5/16" Socket Head Cap Screws, McMaster-Carr 92196A191<br />
qty 2 4-40 x 1.25" Socket Head Cap Screws, McMaster-Carr 92196A302<br />
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The printed parts are available on <a href="http://www.shapeways.com/">Shapeways</a><br />
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Shaft: <a href="http://www.shapeways.com/model/903741/shaft-coupler-hitec.html?li=productBox-search">http://www.shapeways.com/model/903741/shaft-coupler-hitec.html?li=productBox-search</a><br />
Bracket: <a href="http://www.shapeways.com/model/903740/bonnet-ss-4p4t.html?li=productBox-search">http://www.shapeways.com/model/903740/bonnet-ss-4p4t.html?li=productBox-search</a><br />
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<br />RMhttp://www.blogger.com/profile/14180745747728028165noreply@blogger.com6tag:blogger.com,1999:blog-1798970477996519510.post-37354655799490288112012-10-02T23:54:00.003-04:002012-10-02T23:54:54.187-04:00The "Open" PartAs I said in the previous post, I've been working on things that run on magic smoke. The board has reached a certain level of maturity where I'm willing to share. By that I mean I've tested it and it all works - Its not all that pretty and there are some things I'm working on improving. But the design is at a point where I feel someone else could pick it up and have a reasonable chance of reproducing it.<br />
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So, I've uploaded all the relevant information, schematics, layout, gerber files, PDFs to a project page on the www.rocketmoonlighting.com site.<br />
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<b><i><a href="http://www.rocketmoonlighting.com/projects/controller">Check It Out</a></i></b><br />
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<li><a href="http://www.parallax.com/propeller/" style="color: rgb(54, 102, 203) !important;">Parallax Propeller P8X32A</a> - 8 cores, 80Mhz each</li>
<li>8 12 bit, single ended Analog input channels, max 44k total samples per second</li>
<li>3 high current, low side MOSFET drivers (approximately 20A each)</li>
<li>12 servo channels, independently configurable as inputs or outputs</li>
<li>Direct drive of <a href="http://www.amazon.com/ACDelco-D514A-Ignition-Coil-Assembly/dp/B000IZ2C3K/ref=sr_1_1?ie=UTF8&qid=1347855186&sr=8-1&keywords=D514+coil" style="color: rgb(54, 102, 203) !important;">AC Delco D514</a> ignition coil</li>
<li>Onboard <a href="http://invensense.com/mems/gyro/mpu6050.html" style="color: rgb(54, 102, 203) !important;">MPU-6050 Six-Axis Motion Sensor</a></li>
<li>Designed to run on 2 cell Lithium Polymer battery</li>
</ul>
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RMhttp://www.blogger.com/profile/14180745747728028165noreply@blogger.com2tag:blogger.com,1999:blog-1798970477996519510.post-46112814166099438002012-07-31T00:02:00.001-04:002012-07-31T00:02:13.546-04:00Electrons<div class="separator" style="clear: both; text-align: left;">
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I've been working on some engine controller modules lately - not much rocket plumbing related things going on.</div>
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Below is a picture of some of the boards I've had made. I'm expecting rev 3 to be delivered early next week. This is my first "serious" circuit board design effort and I've found it to be more challenging than I thought initially. The 2.5 x 3.0" board replaces a stack of 2 2.5x3.5" boards in addition to adding some functionality.</div>
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I'm planning on making the design available when its finished.</div>
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<br />RMhttp://www.blogger.com/profile/14180745747728028165noreply@blogger.com3tag:blogger.com,1999:blog-1798970477996519510.post-67817312968111372292012-05-27T16:52:00.001-04:002012-05-27T16:52:24.413-04:00Valves By RequestI had a request for additional details on some of the valves I use. I polished up my <a href="http://docs.google.com/viewer?a=v&pid=sites&srcid=cm9ja2V0bW9vbmxpZ2h0aW5nLmNvbXxob21lfGd4OjQ0YzkzYmUwMmUyZmQxZTg">drawing</a> and loaded it on the website, <a href="http://www.rocketmoonlighting.com/valves">www.rocketmoonlighting.com/valves</a>. It includes a little bit of useful details about o-ring material as well as McMaster-Carr part numbers.<br />
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Open Source Hardware is all the rage these days. I'm not sure that OSH will be quite the revolution that OSS was - replicating hardware from a "source" has a higher barrier to entry than replicating executable software from source. It also takes more time and effort to develop new hardware - I wonder about the sustainability of OSH because in the end, people have to be compensated for their time somehow.<br />
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In any case, part of the point of this post is that I do requests! So if people have things they want to see, drop me a line or post a comment.RMhttp://www.blogger.com/profile/14180745747728028165noreply@blogger.com0tag:blogger.com,1999:blog-1798970477996519510.post-34838294931053076552012-05-05T11:58:00.004-04:002012-05-05T11:58:58.244-04:00Plastic Rockets<div class="separator" style="clear: both; text-align: center;">
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Sort of. I ordered two of my latest chamber designs in plastic from shapeways.com. The cost is very inexpensive and even though i can really fire them, they do help to visualize the design. Its also useful for fitting up the chamber to other components like the test stand.</div>
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<a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhdYNjt5X50oiWexztQOICM3AXtPPygXosiOIH0jnn72bfdNQtAevkmCbx2MNehcE9x75cNf2Xzdcx0nKFs_fT8RGjOipIq9L4kyUhlhh2YJAN_8pQMcqGDJsdtl032rJNlkbFBzNoK7sg/s1600/DSC_0660.JPG" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="320" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhdYNjt5X50oiWexztQOICM3AXtPPygXosiOIH0jnn72bfdNQtAevkmCbx2MNehcE9x75cNf2Xzdcx0nKFs_fT8RGjOipIq9L4kyUhlhh2YJAN_8pQMcqGDJsdtl032rJNlkbFBzNoK7sg/s320/DSC_0660.JPG" width="212" /></a></div>
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The picture above is the 50 lbf scaled up design that I did on request. The material is Shapeways' Frosted Ultra Detail and it came out very well. The regen passages are very crisp and well defined. The only drawback is that they are still full of powder. I actually mailed this part over to the individual who asked about the feasibility of scaling up the thrust. <br />
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As you can see in the picture below, the 50 lbf version is comparable in size to my original chamber, which is only 12 lbf. The original chamber was fairly conservative in size, and so the results of testing and additional analysis indicate that the chamber volume can be quite a bit smaller for a given thrust level. The other plastic model is version two of the 12lbf motor - notice the size difference. This part was printed in Shapeways' Transparent Detail material and the results were not quite as good. I'll be using Frosted Ultra Detail in the future.<br />
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<a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhgSMR9vb80lWSEYhk6SN-cGHZGDJecG_QJC-8qBwbPXS2Z-yKgcja3LpFC4W1oRRCz-prkSw6Lh0VNzTkqUgiRiCgyhUgOADBs0KxXA4DMskrWU2OOl9_qmP_enUhcCprbwPjdQq9sa3E/s1600/photo.JPG" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="320" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhgSMR9vb80lWSEYhk6SN-cGHZGDJecG_QJC-8qBwbPXS2Z-yKgcja3LpFC4W1oRRCz-prkSw6Lh0VNzTkqUgiRiCgyhUgOADBs0KxXA4DMskrWU2OOl9_qmP_enUhcCprbwPjdQq9sa3E/s320/photo.JPG" width="240" /></a></div>
<br />RMhttp://www.blogger.com/profile/14180745747728028165noreply@blogger.com1tag:blogger.com,1999:blog-1798970477996519510.post-28679792891127820482012-04-19T00:33:00.000-04:002012-04-19T00:33:56.220-04:003D Printed Rockets: The Cost CurveIf you've been around the rocket community, you may have heard of the "square cube law". Basically, there are some physical parameters of machines that vary as a function of the square of length dimensions. Thrust in a rocket engine for instance, is a function of the throat area, which is in turn a function of the throat diameter squared. Volume and therefore mass is a function of the cube of a length parameter. As a result, when scaling up the thrust of a rocket engine, the mass only increases with the square root of the ratio of the thrust.<br />
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So what? In manufacturing, part of the cost of making a part is the amortization of the capital cost of the machine used to make a part. In conventional machining techniques, labor and other costs also play heavily. However, in additive techniques like DMLS, the cost to make a part is largely driven by the cost of the DMLS machine: as a result, the cost of a part is generally proportional to the volume of metal in the part. <br />
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<a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEg4r03F0txBSZZjB5mcKipV4YEp3IUATbe4dutRgBc0fTD5uN9ltnMn28trJ-GlWE9XpUO4GmqH7VO8jY9CebfhdV2-6yvX85LLP6h3S1w4yI6eENXLx9ABZeh7we0S1KQranDjHd8Pp3g/s1600/COMPARO.png"><img alt="" border="0" id="BLOGGER_PHOTO_ID_5718749081184708194" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEg4r03F0txBSZZjB5mcKipV4YEp3IUATbe4dutRgBc0fTD5uN9ltnMn28trJ-GlWE9XpUO4GmqH7VO8jY9CebfhdV2-6yvX85LLP6h3S1w4yI6eENXLx9ABZeh7we0S1KQranDjHd8Pp3g/s320/COMPARO.png" style="display: block; height: 256px; margin-bottom: 10px; margin-left: auto; margin-right: auto; margin-top: 0px; text-align: center; width: 320px;" /></a><br />
Consider the three chamber designs above. The chambers progress up in thrust by a factor of 10 from right to left. So the first chamber is 10 lbf thrust, the second 100 lbf, and the third 1000 lbf. Because of "the square cube law" the chamber on the right only has about 10 times as much metal material as the chamber on the far left - despite having 100 times the thrust. Do to the wonder additive manufacturing, we could estimate that if the 10 lbf chamber cost $1, then the cost of the 1000 lbf chamber would only be about $10. In real numbers, that means a 1000 lb chamber could probably be printed using DMLS for less than $10,000 - a pretty significant price point compared to other manufacturing techniques.<br />
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<a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEh4gH_Xt6O3mpuZY5toCtwX75ZUHEgHkdEuKECeTLgKF09gFW2bTvJOJKqpbxbILPbZjPeYKdFBMR5VvgqhiqEf7JOkSVJG5oBJrKG5FagIJQqS9FAU-8veU8FmH-5LcIWtcM2dmjDgWJ4/s1600/PR14-1-101.png" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="233" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEh4gH_Xt6O3mpuZY5toCtwX75ZUHEgHkdEuKECeTLgKF09gFW2bTvJOJKqpbxbILPbZjPeYKdFBMR5VvgqhiqEf7JOkSVJG5oBJrKG5FagIJQqS9FAU-8veU8FmH-5LcIWtcM2dmjDgWJ4/s320/PR14-1-101.png" width="320" /></a></div>
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I recently got an email from someone asking about the feasibility of a 50lbf version of my DMLS chamber. I spent a few hours and drew the above model. Interestingly, this model has nearly the same metal material as Version1 of my DMLS chamber - which means that despite being rated for 5x the thrust, it could be made for roughly 1.5x the cost. The primary mass reduction comes from the learning curve of the first DMLS chamber and being able to downsize based on the test results from V1.RMhttp://www.blogger.com/profile/14180745747728028165noreply@blogger.com2tag:blogger.com,1999:blog-1798970477996519510.post-15377299502287103222012-03-18T23:23:00.000-04:002012-03-18T23:23:02.484-04:00More TestingHere are three more videos of DMLS Chamber testing.
The first two are long duration tests of the regen cooling:<br><br><br><br>
<iframe width="560" height="315" src="http://www.youtube.com/embed/bt2vQdgpZZg" frameborder="0" allowfullscreen></iframe><br><br><br><br>
This second long duration video is at a slightly higher O/F ratio, thus resulting in a lower flame temperature and reduced heating of the chamber walls.<br><br><br><br>
<iframe width="560" height="315" src="http://www.youtube.com/embed/MlJ9Xh8sIEA" frameborder="0" allowfullscreen></iframe><br><br><br><br>
In the last video, I was experimenting with camera settings trying to better capture the plume color and Mach diamonds. It didn't work too well. What did work well was the multiple starts/stops on chamber. Each stop/start is commanded remotely.<br><br><br><br>
<iframe width="560" height="315" src="http://www.youtube.com/embed/W_idSgO0jlQ" frameborder="0" allowfullscreen></iframe><br><br><br><br>RMhttp://www.blogger.com/profile/14180745747728028165noreply@blogger.com0tag:blogger.com,1999:blog-1798970477996519510.post-70792915890750326662012-02-17T00:56:00.003-05:002012-02-17T01:00:38.573-05:00Chamber DesignsI'm trying to decided what/if my next chamber will be. Should it be purely self-pressurized like the first one? Or should I pressurize the propane to get Pc and therefore Isp and thrust/weight up a bit? Should it be about the same thrust level as the first at 5 kgf? Or should I go for more like 10 kgf or even 20 kgf?<br /><br />Here is a picture of my design for essentially the same specs as V1, just refined for improved cooling and manufacturing.<br /><br /><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjCbmBegZq9rmtKNKYP6d7AAY0QtFG_WrRl4iLT-sBrqzM9OSV3plIIPOG1aYDDFT1AsPRCUjI2NqfM1HuJKFe8lviM_wB_QVZe-oVti0ekIOhvAK1BLysyV4PNuXMdTZhcThz7aW6-z14/s1600/DMLS_CHAMBER_V2.png"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 320px; height: 254px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjCbmBegZq9rmtKNKYP6d7AAY0QtFG_WrRl4iLT-sBrqzM9OSV3plIIPOG1aYDDFT1AsPRCUjI2NqfM1HuJKFe8lviM_wB_QVZe-oVti0ekIOhvAK1BLysyV4PNuXMdTZhcThz7aW6-z14/s320/DMLS_CHAMBER_V2.png" border="0" alt="" id="BLOGGER_PHOTO_ID_5709980061577612210" /></a><br /><br />Here is a derivative of the above design for a chamber pressure of 200 psi and thrust of 20 kgf.<br /><br /><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEi__e2_cdhrM2_7T7GGqKpC6Bl5iMizQGPOxJ4zmtU58FgshfXyBFlYxYUlXRnR8WOrEe85CYL6zV-AExDOxgceViuKN8sTWYphCDJ7pt9L8RnSrvr89-ci3Cl_Mp_EBIeFxDQNvcNX77A/s1600/DMLS_CHAMBER_V2_22LB.png"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 320px; height: 258px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEi__e2_cdhrM2_7T7GGqKpC6Bl5iMizQGPOxJ4zmtU58FgshfXyBFlYxYUlXRnR8WOrEe85CYL6zV-AExDOxgceViuKN8sTWYphCDJ7pt9L8RnSrvr89-ci3Cl_Mp_EBIeFxDQNvcNX77A/s320/DMLS_CHAMBER_V2_22LB.png" border="0" alt="" id="BLOGGER_PHOTO_ID_5709980063147407570" /></a>RMhttp://www.blogger.com/profile/14180745747728028165noreply@blogger.com2tag:blogger.com,1999:blog-1798970477996519510.post-86631906266758796002012-02-09T23:45:00.004-05:002012-02-11T23:17:38.539-05:00DMLS Rocket "Group Buy"?I'm finishing up design modifications to my DMLS printed chamber: <a href="http://www.rocketmoonlighting.com/projects/printed-chamber">http://www.rocketmoonlighting.com/projects/printed-chamber</a><br /><br />I am planning to have the latest version printed sometime in the next few weeks - there are a few minor tweaks and improvements over the original which worked quite well. <br /><br />There is a significant price reduction per unit when ordering more than one part, so if people are interested, it makes sense to buy more than one. Depending on the number of units, the price could be around half what it costs to make a single part. The price would be in the very low 4 digit range.<br /><br />If you're interested, per the specs on the website above, drop me an email (i n f o at rocketmoonlighting.com). If I get a few responses, I'll do some homework and send out an email with more details to those who expressed interest.RMhttp://www.blogger.com/profile/14180745747728028165noreply@blogger.com3tag:blogger.com,1999:blog-1798970477996519510.post-53859218454449287812011-12-11T12:42:00.003-05:002011-12-11T12:44:55.810-05:00Update - Throttling the DMLS<iframe width="560" height="315" src="http://www.youtube.com/embed/JqDkgrQTP_Q" frameborder="0" allowfullscreen></iframe><br /><br />Just a short note - I tested the DMLS chamber in the throttling configuration. All the previous tests were with on/off solenoid valves. Thrust level reached approximately 80% before the test was stopped when the stand started rolling.RMhttp://www.blogger.com/profile/14180745747728028165noreply@blogger.com3tag:blogger.com,1999:blog-1798970477996519510.post-77130647751253713682011-08-13T11:04:00.013-04:002011-08-13T11:57:29.833-04:00Testing Update<a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjvhSHVzYJ06H4cKYcX4w2Ex-xBS06oFTdUCIVOxXaJLTnfqp43UeIUeKWl3sFMboS1e2mkkwc5QfuoN1PEy5X91y2lqx1xqE_tC9IYhfHm4AmN3trEULnoQ2mCg7sXEGI5krfq6F69Yg0/s1600/DSC_0483.JPG" onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 320px; height: 213px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjvhSHVzYJ06H4cKYcX4w2Ex-xBS06oFTdUCIVOxXaJLTnfqp43UeIUeKWl3sFMboS1e2mkkwc5QfuoN1PEy5X91y2lqx1xqE_tC9IYhfHm4AmN3trEULnoQ2mCg7sXEGI5krfq6F69Yg0/s320/DSC_0483.JPG" border="0" alt="" id="BLOGGER_PHOTO_ID_5640364433246719298" /></a><div>
<br /></div><div>The DMLS chamber has accumulated 18 starts and 152 seconds of firing time. The last test was 31 seconds in duration reached something close to steady state according to the regen coolant temperature measurement.</div><div>
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<br /><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiU2G8kHI4Q_0cVpEbKGRa5CUZ7V9Gg5hr8hvYPwRwdqcsf_fd-bQESW1P-arAaj3n1m4DXgQwrIXNDr5-VVYF51Y5KIz65sZYJssSeL5vBnBlz2bCYNbMr1T5OpTuhOvGtirI-VGh5YS8/s1600/Long_Regen.PNG" onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 320px; height: 193px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiU2G8kHI4Q_0cVpEbKGRa5CUZ7V9Gg5hr8hvYPwRwdqcsf_fd-bQESW1P-arAaj3n1m4DXgQwrIXNDr5-VVYF51Y5KIz65sZYJssSeL5vBnBlz2bCYNbMr1T5OpTuhOvGtirI-VGh5YS8/s320/Long_Regen.PNG" border="0" alt="" id="BLOGGER_PHOTO_ID_5640364430675553442" /></a>
<br /><div><div style="text-align: left; ">The graph shows the measured temperature of the N2O in the regen coolant jacket near the exit. Notice the temperature actually decreases in the last few seconds of the test, even though the propellant flow rates are constant through out the entire test. Notice also that the N2O is a gas at that temperature.</div><div>
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<br /></div><div>Some of the early tests ended with glowing red sections of the chamber. I think there are several things going on here. One is that there are some manufacturing flaws in the injector that result in a non-symmetric injection patter, which I think is making locally hotter combustion. Another is that, at low chamber pressure conditions, the regen design is really marginal - I spent most of my time making sure it would work well at the 100% thrust level. I think the main issue is that the channels in the barrel section of the chamber are spaced too far apart.</div></div><div>
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<br /><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhO4PW1ndZk5o7p3m1MykkZ2IYdkhRl2HRa4JhQHIBsABGIfi1qML9g44TStK6LnG5yw4M7qQ9FYg7usPrfDzzePQrvhLtsnrhNxn2nuEuIxzB9L9VbTZ8wwMpawOXW0W40XXG3i2dg0xk/s1600/dmls_channels.PNG" onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 320px; height: 189px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhO4PW1ndZk5o7p3m1MykkZ2IYdkhRl2HRa4JhQHIBsABGIfi1qML9g44TStK6LnG5yw4M7qQ9FYg7usPrfDzzePQrvhLtsnrhNxn2nuEuIxzB9L9VbTZ8wwMpawOXW0W40XXG3i2dg0xk/s320/dmls_channels.PNG" border="0" alt="" id="BLOGGER_PHOTO_ID_5640364418203735618" /></a><div style="text-align: center; ">
<br /><div style="text-align: left;">When I first saw the red-hot walls, my first concern was that the N2O was decomposing in the coolant channels. However, based upon the regen temperature measurements this does not seem to be the case. Also, the pictures and video indicate that the hottest wall sections are between channels which is the opposite of what you would expect if the nitrous was decomposing into N2 and O2 at 3000 degrees Fahrenheit. </div><div style="text-align: left;">
<br /></div><div style="text-align: left;">The next tests will be focused on step-wise increasing the chamber pressure to the 100% level and decreasing the O/F ratio. Once I have the operating limits mapped out, I'll decide whether to revise the design, or move to the next step of the project.</div></div><div><div style="text-align: center;"><span class="Apple-style-span"><u>
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<br /></div></div></div></div></div>RMhttp://www.blogger.com/profile/14180745747728028165noreply@blogger.com0tag:blogger.com,1999:blog-1798970477996519510.post-50131709355309176432011-07-23T12:28:00.002-04:002011-07-23T12:36:01.279-04:00Testing UpdateI've finally fired the DMLS regen chamber! Two tests so far of 2 and 3 second duration at 50% power level and relatively high O/F ratios<div><br /></div><div>Here's the video of the second test:</div><div><br /></div><div><iframe width="560" height="349" src="http://www.youtube.com/embed/IkxgGI1iW2g" frameborder="0" allowfullscreen=""></iframe></div><div><br /></div><div>What I've demonstrated so far-</div><div><br /></div><div>- You can actually print a "tube stub" in your motor and use a Swagelock nut/ferule set to attach instrumentation</div><div>- My additional measurements (temperature and regen pressure) are working well.</div><div>- The direct spark ignition with the D514A coil is working. </div><div>- There don't appear to be any blockages or leaks in the regen jacket.</div><div>- C* efficiency is reasonably high - approximately 90%.</div><div><br /></div><div><br /></div><div>The big question still remains to be answered - will the motor survive long duration operation as the temperatures reach steady state. </div>RMhttp://www.blogger.com/profile/14180745747728028165noreply@blogger.com0tag:blogger.com,1999:blog-1798970477996519510.post-53759770368853659822011-06-11T19:41:00.002-04:002011-06-11T20:02:59.764-04:00No Testing Yet<div style="text-align: center;"><br /></div><img src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEi1XmshVWKFZqdfqQxJGhfQiLSft1NFqvu3-8M8OOL9FLaMUfXERXoY5ycM6CjNESSniPGFtxIyDcaxO-9kNPryt5C7wnEJe2OTAa850ntmVnLZKJVveCIdhg-xX2_OPk_HFLFfQOVZkZ8/s320/IMAG0030.jpg" style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 320px; height: 191px;" border="0" alt="" id="BLOGGER_PHOTO_ID_5617114150538714722" /><div><div style="text-align: center;"><br /></div><div style="text-align: justify;">Everything is ready to go on the stand - all the instrumentation is connected and checked out - I just haven't made the time to buy another nitrous bottle and test. I'm measuring the following in this setup:</div><div style="text-align: justify;"><br /></div><div style="text-align: justify;">N2O supply pressure</div><div style="text-align: justify;">Propane supply pressure</div><div style="text-align: justify;">Regen jacket pressure</div><div style="text-align: justify;">Regen jacket temperature</div><div style="text-align: justify;">Chamber pressure</div><div style="text-align: justify;">Oxidizer flow rate</div><div style="text-align: justify;"><br /></div><div style="text-align: justify;">I have a flow meter installed on the fuel side, but the flow rate will be too small for the meter. I'd love to measure fuel flow as well, if some one has a 0-1 gpm turbine meter that they're not using...</div><div style="text-align: justify;"><br /></div><div style="text-align: justify;">The injector for this chamber is a pintle configuration based upon the design I showed in previous posts. I had a local shop EDM the 8 0.014" injector holes in 1/8" instrument tube and then pinched off the end of the tube.</div><div><br /></div><img src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiM01xOF9j-bGgicZybHTWUnNVmMVNhzxvuj2Qy58OP5e6ymr_mDcwjRdm-iZsvM8z3OhN-y1Jl8G_fahw52UWz4VmAVQFxd8w8MbRUikGEv1IayBsvxOUMXYHKqqc4BdrYu_r_8bks31w/s320/DSC_0329.JPG" style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 320px; height: 213px;" border="0" alt="" id="BLOGGER_PHOTO_ID_5617114162625601826" /></div><div><div style="text-align: center;"><br /></div><div style="text-align: left;">This is a picture taken through a microscope showing the EDM holes. The price was extremely reasonable - drop me a line if you interested having some small hole EDM work done.</div><div style="text-align: center;"><br /></div><img src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiyxySDAzyIC5fR-rm3-i5HPHYII2cArJulT1MFhtR4JpB5u78mLSkhpvdPzQOnNJbiiKe99XQiujlZM938X8t65bxkjmfxhrbkndRIMexkx4-N3e0uShjAsQQCsEwTkP00o4jEIsQvRlw/s320/photo2.JPG" style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 320px; height: 239px;" border="0" alt="" id="BLOGGER_PHOTO_ID_5617114168821324578" /><div style="text-align: center;"><br /></div><div style="text-align: left;">Hopefully I'll be able to do some limited ignition testing soon.</div><div style="text-align: center;"><br /></div></div>RMhttp://www.blogger.com/profile/14180745747728028165noreply@blogger.com0tag:blogger.com,1999:blog-1798970477996519510.post-21725630445639715152011-03-04T23:24:00.003-05:002011-03-05T00:06:08.085-05:00What Its All About<div><div>Engineering is about making <i>things</i>. For me, it is incredibly satisfying to conceptualize something and then make it exist and work as intended. I think that is why 3D printing technologies have captured my imagination - they are a step towards a Star Trek style "replicator". They offer the promise of shortening the loop between concept and reality.</div><div><br /></div><div>I've been dreaming of different projects for the <a href="http://en.wikipedia.org/wiki/Direct_metal_laser_sintering">DMLS</a> process for over three years now. A couple weeks ago, I took the plunge and had a chamber printed in 15-5 stainless steel. The first picture is the CAD, the second obviously the manufactured result. It really is a thrill to send electrons across the country and open a box a few days later to find the electrons made metal.</div></div><div><br /></div><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgkkEUk7eV9qVn10158_gHCs2RLQQDUtL7RAho8pl1EP5HyDl4ynCB9YPsWSmfvGmHF2Ej-KgkgzKwTw0H2vA9ldnszn_BykXa4ZwdTwteqPqbm22F9iE277HeBHO40JYiJ-WUBdA1ZGwE/s1600/Picture1.png"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 320px; height: 187px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgkkEUk7eV9qVn10158_gHCs2RLQQDUtL7RAho8pl1EP5HyDl4ynCB9YPsWSmfvGmHF2Ej-KgkgzKwTw0H2vA9ldnszn_BykXa4ZwdTwteqPqbm22F9iE277HeBHO40JYiJ-WUBdA1ZGwE/s320/Picture1.png" border="0" alt="" id="BLOGGER_PHOTO_ID_5580457651685799746" /></a><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEit2WCRrFHRajDxCtQy7RGnDLpawJMT3q1a_VHFdiphKp4obLDtebSa2XEMu-TL7WBD6hKAQlSpUryXamByaun15WohQ95s1XcGr4lJ2bM6Z95I8g0VrqV1bYh8k1mY4qfqHDjDOzHGGzI/s1600/IMG_0620.jpg"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 320px; height: 239px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEit2WCRrFHRajDxCtQy7RGnDLpawJMT3q1a_VHFdiphKp4obLDtebSa2XEMu-TL7WBD6hKAQlSpUryXamByaun15WohQ95s1XcGr4lJ2bM6Z95I8g0VrqV1bYh8k1mY4qfqHDjDOzHGGzI/s320/IMG_0620.jpg" border="0" alt="" id="BLOGGER_PHOTO_ID_5580457644907460706" /></a><div><span class="Apple-style-span" style="-webkit-text-decorations-in-effect: underline; "><br /></span></div><div><span class="Apple-style-span" style="-webkit-text-decorations-in-effect: underline; color: rgb(0, 0, 238); "><span class="Apple-style-span" style="color: rgb(0, 0, 0); "><div>Now, some of you are saying "but you can do that with conventional machining" and you are right. But having a part machined has a certain activation energy - it requires a non-trivial amount of effort and skill. 3D printing is still not effortless - there are rules about what geometries are printable and of course you have to be able to generate a 3D model of your part. But the barriers are much lower. And there is also the fact that it can make geometries which are expensive or even impossible with conventional manufacturing techniques. It is still expensive - my part cost 4 figures even though it is quite small. In fact, it represents the larges single purchase I've made to date on my rocket hobbies. But as with any other process, buying in quantity is cheaper.</div><div><br /></div><div>Everything in grey in the CAD picture came as is from the DMLS machine. As you may notice it is a regen chamber and instrumentation ports are integral to the DMLS part. Threads for the spark plug and inlet fitting were printed slightly undersized (extra metal) and then I cleaned them up with a tap by hand. The part came out more or less as I drew it, although there were some imperfections that affect the design. I'm talking with the vendor about ways to modify the design to avoid those problems on future builds.</div><div><br /></div><div>Testing will follow soon. Had this been my "day job" I could have tested the motor the same day that it was delivered. Installing fittings and tapping out the holes took about an hour of slow work. The mounting ears fit directly on my stand as is. Unfortunately, life is a bit busy these days for me. And I still need to get some thermocouples for coolant temp measurements.</div><div><br /></div><div>Questions welcome!</div></span></span></div>RMhttp://www.blogger.com/profile/14180745747728028165noreply@blogger.com12tag:blogger.com,1999:blog-1798970477996519510.post-27937399599552702012010-12-12T13:16:00.001-05:002010-12-12T13:18:52.865-05:00Happy Holidays!<object width="640" height="385"><param name="movie" value="http://www.youtube.com/v/1gObC7sNMxg?fs=1&hl=en_US"></param><param name="allowFullScreen" value="true"></param><param name="allowscriptaccess" value="always"></param><embed src="http://www.youtube.com/v/1gObC7sNMxg?fs=1&hl=en_US" type="application/x-shockwave-flash" allowscriptaccess="always" allowfullscreen="true" width="640" height="385"></embed></object>RMhttp://www.blogger.com/profile/14180745747728028165noreply@blogger.com1