johnlove_mk_II Posted March 5, 2017 Share Posted March 5, 2017 Just sent off the motor mount parts to Ponoko, should see them mid-March. It'a basically a couple of plates with a cruciform support between them. The round holes are for 5.5mm brass tubes. I'll be drilling LVM motors to accept the next smallest diameter tubes, they should slide right into place. May be a little over-kill, but it should be very robust. Full steam ahead. Quote Link to post Share on other sites
johnlove_mk_II Posted March 6, 2017 Share Posted March 6, 2017 The F-1 fairings. These innocuous little guys are far more complex than you’d think. I thought of a few different ways to make them, none of which are particularly easy or cheap. 1) Vac-u-form - Make a plug. Form sheet into shape. Detail with styrene strips. - Tedious, structure could be weak. 2) 3D printed - Model. Print. Mount. - Easy, but expensive when printed in the detail plastics. Will be very brittle. 3) 3D printed armature, with detailed styrene overlay - Print the armature in white strong plastic, cover with detailed wrap. - Stronger, cheaper and detailed. 4) Buy Apogee fairings - Order. Wait. Mount. - All the examples I’ve seen online, the stringers seem soft and incomplete. Sill thinking about this, but this is what I’ve come up with so far. Quote Link to post Share on other sites
Hotdog Posted March 7, 2017 Share Posted March 7, 2017 You could probably get away with printing them in WSF polished to save money. The only parts that may require the FUD or FXD printing are the air scoops, fins and maybe the inner ribs. You could make those separate pieces. Quote Link to post Share on other sites
niart17 Posted March 7, 2017 Share Posted March 7, 2017 Hi John. Looking VERY good. The fairings are actually what stopped my build dead in it's tracks. I ordered the Apogee set and yes, they are pretty weak in detail and VERY thin and flimsy. A better builder than I could probably make them work but I couldn't use them at all. I looked at printing and even in WSF they are quite expensive. I thought of maybe ordering 1 in a higher grade material and then casting copies but the thought of it is as far as I got. If you come up with something I'd love to be able to finish my build too. I'm so tempted to just ask someone to sell me a new stock kit end piece to replace the one that I destroyed trying to fit the Apogee parts on and just go with fairing that are woefully too short. Keep up the great work! Bill Quote Link to post Share on other sites
johnlove_mk_II Posted March 10, 2017 Share Posted March 10, 2017 Thanks for the confirmation on the Apogee Fairings. I figured they were made with the same thickness sheet as the wraps, and those are almost too thin to be useful. I’ve set aside the fairings until I get the wraps and stringers situated. I figured it would be best to have a better idea of how they all would interact with each other before I really started nailing down what I was going to do. I have the wrap files created for the Silhouette cutter, I just need to confirm the fit. This weekend I’ll hopefully get everything situated so I can proceed with designing the fairing mounts and figure out the fins. In other news, Ponoko has fabricated and shipped the F-1 mounting platform. It’s scheduled for delivery Saturday. Quote Link to post Share on other sites
Hotdog Posted March 11, 2017 Share Posted March 11, 2017 Wondering how you're going to make the wraps on your Silhouette cutter. I had thought about doing mine that way, but how would you handle the stringers? Will you be applying each one by hand? Quote Link to post Share on other sites
johnlove_mk_II Posted March 11, 2017 Share Posted March 11, 2017 Yes, all tediously by hand. I plan to split the wrap into four sections for ease of install and cutting size limitations. Each "seam" will be hidden under the fairing and each of the stringer guides are slightly smaller in width than the 1mm Evergreen strips I'm using for the stringers. They should be covered completely. Here's the pattern for the cutter. I still need to make a few tweaks, but it's almost ready. The center cut-out is for the 3D printed hold-down parts. Quote Link to post Share on other sites
johnlove_mk_II Posted March 11, 2017 Share Posted March 11, 2017 (edited) The postman just dropped off my Ponoko order. Opened the box and the house was filled with the smell of charred paper and melted acrylic. The parts turned out great and fit almost perfectly. Just need to do a slight bit of sanding to get it snug and perfect. Edited March 11, 2017 by johnlove_mk_II Quote Link to post Share on other sites
crackerjazz Posted March 12, 2017 Share Posted March 12, 2017 Looking great -- looking forward to more progress shots. Ponoko -- wow -- great tip! Quote Link to post Share on other sites
johnlove_mk_II Posted April 20, 2017 Share Posted April 20, 2017 This fairing thing, I’m pretty sure it’s going to kill me. I’ve been working on it for the better part of 4 weeks … on and off of course, but never really getting anywhere. So after all that, where do I stand? Well, kinda where I began. At first thought I just thought that I’d just print the fairings. It’s not particularly difficult to model in 3D … the problem is the printed parts would cost far more than I’d be willing to spend. After drawing the basic she, with no details, a single fairing in FUD costs close to $43. Stepping down to Strong White Flexible, the cost would be $12 per fairing. All four would be $44 and I’d still have to laminate them with styrene to have the level of detail that I want. The other thought is to create a smaller 3D printed armature that would form and support a formed sheet styrene fairing and have a structure that would support the fins and offer an attachment point for the S-IC. The more I think about this, the more I like it. I'm currently working out the details for this scheme ... in the mean-time, I’ve been knocking out some of the other S-IC details that I'll need. Aft umbilicals LOX vent - assembled and in parts. Quote Link to post Share on other sites
Hotdog Posted April 20, 2017 Share Posted April 20, 2017 I feel your pain. I've been battling the same issue in planning my 1/72 Sat V build. I have all of the stringer wraps made and the heat shield file ready for Ponoko laser cutting, but i'm in the same spot on the engine fairings. Can you 3D-print one in really nice detail with all of the stringers and everything, then cast them and make resin copies? I'd do that, but I don't have your 3D skills, and I have no experience casting with resin. Quote Link to post Share on other sites
johnlove_mk_II Posted April 21, 2017 Share Posted April 21, 2017 I had briefly considered resin casting, but I think I'd seriously muck it up. I think it would take some skill, that I certainly don't have, to make a mold that would work with the thin walls. Quote Link to post Share on other sites
Youngtiger1 Posted April 23, 2017 Share Posted April 23, 2017 John, if you decide to cast them and sell, then I'll grab a set from you for sure. I have this kit and would love a set to fix this problem as well. Quote Link to post Share on other sites
habu2 Posted April 24, 2017 Share Posted April 24, 2017 I visited Johnson Space Center last week and took over 250 detail shots of the Saturn V displayed there. Here are some shots of the F1 engine fairings. Quote Link to post Share on other sites
habu2 Posted April 24, 2017 Share Posted April 24, 2017 A couple more Quote Link to post Share on other sites
habu2 Posted April 24, 2017 Share Posted April 24, 2017 I concentrated on the fairings because I never noticed how they stand proud from the lower thrust structure except at the very top where the staging retro-rocket cap is. The posted pics are reduced to 25% original size, and the grainy appearance is due to the relatively high ISO required indoors. Quote Link to post Share on other sites
Hotdog Posted April 24, 2017 Share Posted April 24, 2017 (edited) Yep, just be advised that those fairing and fin hoists are removed before flight :) Edited April 24, 2017 by Hotdog Quote Link to post Share on other sites
johnlove_mk_II Posted April 24, 2017 Share Posted April 24, 2017 Great pictures Habu, thanks for sharing. Quote Link to post Share on other sites
johnlove_mk_II Posted June 25, 2017 Share Posted June 25, 2017 (edited) The super slow burn that is my Saturn V build. I think I may have finally stumbled on to how I can produce the fairings. And it's been under my nose, all along. I had cut some faring shapes with Ponoko earlier on in this build, but was having issues with them splitting along some engraved lines I was going to use as guides to place the stringers. I sat them aside and it wasn't until today that I pulled them out again to ponder how I might still use them. I decided to try the boiling water technique to see if I could get them to curl without splitting. Well the answer is yes, you can ... and it worked really well and without having to do anything more than drop them in the water - it curled all on its own and almost to the exact shape needed. I'll have to design some sort of support / attachment assembly, but I think I may have this issue cracked. Edited June 25, 2017 by johnlove_mk_II Quote Link to post Share on other sites
crackerjazz Posted June 25, 2017 Share Posted June 25, 2017 Wow!!! What thickness styrene did you use and how long did you keep it submerged? Its amazing it curled up to the correct shape without formers. Quote Link to post Share on other sites
johnlove_mk_II Posted June 26, 2017 Share Posted June 26, 2017 It's .025" thick sheet and maybe dipped for about 20 to 25 seconds. I had two sizes of tubing ready to try to form it but it took to the shape you see, without any coaxing ... I was pleasantly surprised. I'll need to have some others cut and hopefully they will react the same way. Quote Link to post Share on other sites
Hotdog Posted June 26, 2017 Share Posted June 26, 2017 Excellent! I was doing the same thing, but was trying to heat them with a heat gun and not getting good results. I'll give the boiling water a try. I was dreading having to 3D print them! Quote Link to post Share on other sites
spaceman Posted June 26, 2017 Share Posted June 26, 2017 Congrats John, the boiling water technique is the only way to go for evenly bending such large-area parts, because with the heat gun the warming is too uneven. Quote Link to post Share on other sites
crackerjazz Posted June 26, 2017 Share Posted June 26, 2017 I'm really eager to see how the next ones turn out. Any styrene sheet I dunk into boiling water becomes a twisted mess whenever it's not wrapped around a forming tool of some sort, so I find it very suprising how yours behaved. I'm wondering if it's those engraved lines that helped it form -- if it would still take a conical shape without them. Quote Link to post Share on other sites
johnlove_mk_II Posted June 26, 2017 Share Posted June 26, 2017 Yeah after it came out like it did, I immediately started wonder why. I do think that the engraved lines helped, but I'm not sure as to the mechanics of it all ... maybe a discontinuous vs. continuous surface type of thing? It was dunked with the engraved lines pointing down and that allowed for the ends to curl up without any resistance from the pot. Like you I'm eager to see if It can be replicated. Quote Link to post Share on other sites
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.