Hubert Boillot Posted November 1, 2015 Author Share Posted November 1, 2015 (edited) A uqick update, with a significant, but not visible progress. The more I use Solidworks, the more I find out that my difficulties in achieving certain shapes is a reflection of my lack of mastery of this software. It is incredibly powerful, if you know how to use it. In fairness, the help function is not that helpful, and training to use it with an outside trainer is mandatory if you want to save time and avoid the pitfalls I fell into. Anyway, I have used skills acquired trough trial and error to refine my design, and correct all the "cheatings" I had done previsously. The loftings for the fuselage and rudder are now much better, outside AND inside for the fuselage, and the Karmans are also a lot better, including the small filet at the trailing edge to fuselage junction. Not much to see on the pics, but the work is a lot cleaner from a design point of view, and that makes me a lot happier. Ah yes, as of today, the 3D Mystery Ship has now a rudder and horizontal tail surfaces Now, on to the wheel spats and their struts ... Hubert Edited November 1, 2015 by MostlyRacers RadBaron, Harold and Leaning_Dog 3 Link to comment Share on other sites More sharing options...
Hubert Boillot Posted November 5, 2015 Author Share Posted November 5, 2015 Still no spats (yet ...) but a cockpit coaming in place (I know the front part should be opaque, but I am not yet mastering changing materials in renderings for only a part of the component, and finally, maybe I could edit a few mm out of it lengthwise) Hubert RadBaron and Harold 2 Link to comment Share on other sites More sharing options...
GuildAero Posted November 5, 2015 Share Posted November 5, 2015 Hubert, whilst I can't do CAD for love or money, I can read a surface and there's something odd going on on that rendering on the side of the fuse. just forward of the windscreen. The definite light line that runs all the way forward from the tail goes decidedly soft, suggesting a "dent" in that surface where there would be no need for one. But there's a dip in the line leading to the screen. Should that really be there? Martin Link to comment Share on other sites More sharing options...
GuildAero Posted November 5, 2015 Share Posted November 5, 2015 (edited) Nope, I think that's a definite area to have another look at. Pictures of the real thing show a much rounder section to the fuse. and no dip in the surface mentioned above. Blame my clay modeller's eye from car company days! Cheers, Martin Edited November 5, 2015 by GuildAero Harold 1 Link to comment Share on other sites More sharing options...
Hubert Boillot Posted November 5, 2015 Author Share Posted November 5, 2015 You're absolutely right, Martin. The surface lofting feature of Solidworks does not let me do all I want it to do, but I have not given up on moving those handles without the software throwing me to hell In fairness, as the 3D print will be layered, I know I will do some smoothing and puttying before turning these half-fuselages into masters for resin-casting ... Thanks for looking. Hubert Harold 1 Link to comment Share on other sites More sharing options...
GuildAero Posted November 5, 2015 Share Posted November 5, 2015 Hubert, quite a bit of car work was done in Solidworks, but nothing which required surfacing. Even then, CATIA had to be surfaced later, something my agent paid for me to learn and which I have completely forgotten as he neglected to get me any work in that discipline! Solidworks was loved by Ford and belittled by every one else in those days. It was amusing to watch grown men getting defensive about software suites that none of them had any hand in developing! I, of course knew nothing of what they were arguing about and was able to laugh at them all. I did however, surface the back end of the WRC Subaru! Martin Link to comment Share on other sites More sharing options...
Hubert Boillot Posted November 5, 2015 Author Share Posted November 5, 2015 I am sometimes totally failing to grasp the mathematical logic behind these magical lofting functions. When one expects gently flowing lines between two stations, it starts throwing in waves in-between for a godforsaken reason. Now I am sure it is because I am not a master, but apparently Brent, who uses the same software for his Martin-Baker MB-2 project here on LSP, had the same kind of issues with bumps and valleys added to what was a fairly straight-flowing fuselage. I have had these waves playing tricks with me since the beginning (so yes, this small depression should not be here, and I have failed to correct it so far). I have improved the result somewhat in my last re-designing session, but it is still not where I want it to be ... When you start "playing" with these 3D softwares, you actually realise that the combination of a good eye, a brain that can think in volume, and a steady hand are still unbeatable. Your clay-modelling talent may be a declining use in some industries, but it is not dead yet ! I understand Solidworks was a one-man development that was a kind of "poor-man"'s CATIA, subsequently taken over by Dassault Systems (who did CATIA). The big brother CATIA is apparently way more powerful. Just way too expensive for my business anyway, assuming I had a way to use it smartly ( I am not an engineer by training after all, rather a marketeer ) Hubert Link to comment Share on other sites More sharing options...
Hubert Boillot Posted November 5, 2015 Author Share Posted November 5, 2015 Well, this site is absolutely fantastic ! One of our members here just gave me access to scans of the Mystery Ship blueprints, apparently as redrawn by Herb Rawdon (the designer of the MS in 1929) himself, in 1974. This is absolutely top notch material, even if the lines are very faint and hard to read some time. I need to cross-check these with some period pics, but if Mr Rawdon's memory did not fail him, then I know I have to start this design again (a big part of it at least) to be closer to these blueprints. Thanks again to our generous friend here ! Hubert Tnarg and Harold 2 Link to comment Share on other sites More sharing options...
GuildAero Posted November 6, 2015 Share Posted November 6, 2015 Now that is a development! Great news. May I recommend Rhino 3D, Hubert. Its main users are aircraft and boat companies and the last I looked, the software was about 700 dollars. It is a poor man's Alias/Maya, which, even though outrageously expensive, even I could use! I think there's even a very cheap student version. You could invent a Monsieur Blogges, who is a student at your company, sponsored by your good self! Solidworks, as I understand it, is a selection of pre-made geometrical shapes to which, or from which, you add or subtract, respectively, so for a shape such as the fuselage is probably most unsuitable except maybe, egg planes! Cheers, Martin Link to comment Share on other sites More sharing options...
Hubert Boillot Posted November 6, 2015 Author Share Posted November 6, 2015 I was following Rhino's development for Mac, Martin, and got tired of waiting. I figured that if I had to have a PC-compatible 3D software (mine runs on my Mac via Parallels), Solidworks was probably better. Our resident expert on Rhino on LSP is Tim, and he has run a very interesting tutorial. The software is assuredly amazing. Personally, I have not spent much time trying to understand how Rhino worked because I had to improve on Solidworks first. The lofting features of Solidworks, the most needed for designing a compound shape like a wing or fuselage are frustrating, I have discovered, even tough it seems it can be tamed to do your bidding. But the 2D designing approach met my experience of technical drafting, and that did it I may end using SW at work, and Rhino, now available for Mac, on my home iMac (which cannot really be upgraded to a hardware level allowing to run SW smoothly on a Parallels environment). I have tried some free software like Blender - a polish gentleman on ARC is producing an unbelievable 3D SBD using this one - butI cannot resolve to using pixels as the originla measurement, rather than good old mm or cms, although there is certainly somewher a way to give dimensions ... The blueprints I received are said to be original, but the dating on them says "74", and I know herd Rawdon redrew them from memory around that period. After a cursory glance, some of the stations look different from the shapes I think I discerned from the period pics. On top of it, when looking at pics, it is fairly evident that the different airframes built (MS - R614K, Pancho Barnes' R613K - originally designed with the Chevrolair in-line engine, Frank Hawk's Taxaco and Dollittle's Shell, and finally the italian one), seem to have had different lines, especilaly when it came to the fuselage. So some cross-checking is necessary. They are however invaluable to me. I now have a clear description of the instrument panel, for instance, and designing these wheel spats is going to be a breeze. Hubert Harold 1 Link to comment Share on other sites More sharing options...
AlexM Posted November 6, 2015 Share Posted November 6, 2015 (edited) Hello Hubert, first let me say that I know nothing about solidworks, I'm just playing around with sketchup and it's loft-plugin (called curviloft). From the cad-pictures I guess you first created the whole fuselage, and then cut out the cockpit-area (viewed from the side), so the upper fuselage shapes in front and behind the cockpit are somehow related. Maybe thats the reason for the unwanted shape of the fuselage-side around the cockpit-area.Maybe it could help to devide the fuselage into two pieces by adding another cross-section with the desired shape, so that the end cross-section of the forward fuselage-part (red curve on the picture below) is only identical with fhe front cross-section of the rear fuselage-part (blue curve) to the height where the cockpit-openings beginns Something like this Cheers Alex Edited November 6, 2015 by AlexM Link to comment Share on other sites More sharing options...
Hubert Boillot Posted November 6, 2015 Author Share Posted November 6, 2015 (edited) Hello Alex, Many thanks for looking and your advice. There are in fact a few frames in the design, including one at the front of the cockpit. The top fuselage shape there is not as rounded as it is after the firewall, with a slight pinch to transition towards the headrest. Maybe my interpretation is a bit too "pinched" (it would seem so after looking at the frames from the blueprints I got yesterday evening). I did some tweaking of the frame this morning, and it is better already. The issue remains that the lofting function produces some wavy lines, and I cannot move the "handles" as I wish... The problem is a bit academic now anyway, as the blueprints give me indications I will have to redo the fuselage ... Hubert Edited November 6, 2015 by MostlyRacers Link to comment Share on other sites More sharing options...
Hubert Boillot Posted November 8, 2015 Author Share Posted November 8, 2015 (edited) Good morning all, I did some further checks of the blueprints. They are indeed signed by "Herb Rawdon Engineering" and dated between Kuly and Auguts 1974. They are to build the replica. The clear indications that it concerns the replica are for instance the mention of the engine (a Lycoming R-680), which is clearly depicted on one general arrangement sheet, and the inclusion of a tailwheel. I now need to check via pics whether, apart from the engine and tailwheel, the replica is strictly identical to the original, but I have frankly some clear doubts about it, even for the general arrangement. Some details are already visibly different in my eye, like the seat, which was more "old-fashioned" on the original Mystery Ship. The plan view of the fuselage is also different, at least from my interpretation based on period pics. A bit of further detective work needed before I start redoing the whole design then ... Thanks for looking Hubert Edited November 8, 2015 by MostlyRacers Link to comment Share on other sites More sharing options...
GuildAero Posted November 8, 2015 Share Posted November 8, 2015 I wouldn't trust replica details. When I do model cars, I never use restoration pics., only period photos in good ol' black and white from Motor Sport magazines. Cheers, Martin Harold 1 Link to comment Share on other sites More sharing options...
RadBaron Posted August 3, 2020 Share Posted August 3, 2020 Just stumbled across this thread. Howd this all play out, Hubert? Link to comment Share on other sites More sharing options...
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