Friday, December 26, 2008

Merry Christmas

I won’t be blogging much until early next year. There is a possibility we may static test our new motor sometime between 31st and 4th. I’m looking forward to more progress in 2009.  The gear box is 90% done I need to make one more bearing plate, but all the major structure is done. All the rotating parts are done. It’s heavier that I would have liked. When I’m done I will fully disassemble and weigh the individual parts.




Sunday, December 21, 2008

Why I like this project....

There is very little I enjoy more than learning something new. A traditional aerospace project is an effort involving thousands of specialties. This offers the opportunity to learn thousands of specialties. I have received my Peroxide compatible pump, fuel pump, and motor. I’m in the process of assembling a gear box. I’ve never built a gear box before so one gets to learn new terms like pressure angle and involute. As well as use new tools.. I’m continuously impressed with the variety of free tools available on the web. I’d gathered all the shafts, bearings, gears, parts and etc in to a big pile on my desk. I spent the better part of yesterday laying out the gear box.

I have a fully 3d capable cad system, but I usually do my layouts as 2D line drawings. I find this easier than making a 3D model. My gear box sketch is below as I have been using it (Labels added for your viewing pleasure)


File Attachment: GearsV2.pdf (24 KB)

I’ve machined the top base plate, the adaptor that joins the peroxide pump to the base plate and the curved offset spacers. (Only shown in top view the semi circular arcs with screw holes ).  Today I’m going to try and build the complicated shaft that connects the two pumps to each other and to the gear drive. I’m also going to finish bore the gears and lighten them. If all goes really well I may even get to a full trial assembly.


This shows the peroxide pump and the aluminum adaptor connecting it to the main plate. It also shows the curved spacers.

Monday Morning update. I machined the shaft and couplers for the pump side , I also lightened he commercial gears and bored the one that needed bored.



Friday, December 12, 2008

Back to Hardware....

We are   were going to go out to the test site and static test the blue ball with a “solid” catalyst. (The FAR event was canceled due to 75mph winds forecast on Saturday as I was typing this.)

John Carmack sent me several catalyst styles, one kind was a pourable ring catalyst from It looks like the picture on the right here. So we had some stainless plates  water jet cut by Thunderbird Water Jet to hold the catalyst rings, and we added a sintered stainless diffuser plate. and reassembled the motor.

Stainless motor 003

When we first cut the motor apart the inside was kind of nasty with permangenate residue.



Catalyst motor 001

A picture of the sintered diffuser plate welded to the support ring.

Catalyst motor 003

A view from the other side as it is welded into the top of the motor.


Catalyst motor 007

A view of the waterjet cut bottom support plate. The area between the two plates is filled with the ring catalyst. The fittings on the side as shown on the view of the motor top allow us to shake the catalyst out and replace it.

Catalyst motor 009

The reassembled motor ready for testing…. soon.

Wednesday, December 03, 2008

New FAA rules.

The new FAA amateur rules were released today. It looks like they will be officially published on the 4th and become effective on Feb 2nd.  Since this removes the burn time limit and requires nothing more than ATC notification for flights in  uncontrolled airspace more than 5 miles from an airport, it basically means ZERO paperwork for the testing and development of a hovering LLC class vehicle that stays under 200K lb/secs of total impulse.  I’m practically giddy!