This is a 2x flyable remix of Greg Glenn's excellent Mars Lander. ***NEW UPDATE*** - I've been working on a major multicolor remix to make this a spacex lander. Take a look at the photos. When I'm done, I'll upload it I've had to make some modifications to several of the files to make it usable in a 2x format. Note - you need a BIG printer for this. I have an Artemis, and it just fits within my print envelope. You shouldn't need to add any supports. For the descent stage, in addition to the supports Glen had, I added more to support the 1010 conformal rail button now integrated into the body. The SVG file is a vector file I made to cut out wooden motor center rings. This is a perfect match a 54mm motor tube, and they will recess into the bottom of the lower core, as well as one in the upper core. Given the size and weight of the final product, I recommend the following additions: 1) I modified the inside of the descent stage and added 4 hooks to connect the landing gear to the body. These extension springs on Amazon work perfectly: https://www.amazon.com/gp/product/B008RG6C3I/ otherwise, source your own 5/8-Inch by 2-1/2-Inch - .072 Diameter springs. I do not recommend using rubber bands 2) In addition to using wood center rings, I recommend traditional fiberglass or paper motor tube. The temperatures of a motor WILL melt your filament. This one will work great: https://www.erockets.biz/loc-precision-body-tube-2-14-54mm-x-17-1pk-loc-mmt-54x17/ 3) I used a 54mm - 3" tailcone motor retainer at the bottom of the motor tube - you can see it hanging down in the first photo. Looks cool, and will help a lot in motor retention. The one I used is available here: https://aeropack.net/webstore/product.asp?productid=34 4) This is probably the most important: I had to add a LOT of weight in the nosecone. I epoxied a lot of lead shot into the nosecone. with my settings (see below), I had to add almost a pound of weight into the nosecone to get beyond marginal stability. Don't mess with the Center of Gravity / Center of Pressure gods..... my settings: Descent Stage: 40% infill Ascent Stage: 58% infill nosecone base: 58% infill nosecone: 100% infill landing gear: 100% infill landing pad: 100% infill lower core: 58% infill