Hardcore Posted August 25, 2015 Share Posted August 25, 2015 I see my input is missing. Best to rectify that now. You are Mad! MAD! MaaAAAaad! Please continue. Link to comment Share on other sites More sharing options...
Hubert Boillot Posted August 26, 2015 Author Share Posted August 26, 2015 Great solution Hubert. Keen to see how it looks under some primer, no doubt it's a big improvement on the kit part. Cheers Jim I see my input is missing. Best to rectify that now. You are Mad! MAD! MaaAAAaad! Please continue. Thank you Jim and Hardcore . yes, I'll continue being mad, now that I am in good company Hubert Link to comment Share on other sites More sharing options...
Ironwing Posted August 26, 2015 Share Posted August 26, 2015 Hu Clever solutions to difficult problems. Nicely done... Best Geoff Link to comment Share on other sites More sharing options...
Hubert Boillot Posted September 10, 2015 Author Share Posted September 10, 2015 (edited) Thank you Geoff. Much appreciated coming from a detail master like you ! Time for an update ... and a change of plans I have actually completed 12 new heads for the engine, and 12 finned exhaust-valve columns. The idea is that I will pick the best 9 out of the 12. This was done some two weeks ago ... Sorry for the poor pics of the parts with dirty cutting mat and workbench lighting ... However, I thought that maybe some people could be interested in copies of the modified engine. But then I am not sure I would have much success casting my makeshift parts. Plus the Whirlwind was used in one form or another on many different aircrafts I would want to model one day, like the Sparrowhawk, or ... the Ford Trimotor, just to name a few, although the heads were different from the ones on the Mystery Ship in that the exhaust port was on the side of the exhaust-valve column, and facing forward - or sometimes aft- , as on my first attempt. So it was time for plan B, i.e. design the engine in scale 3D, and try to get it printed. Plus I am going to invest in a 3D-printer for my company very soon (probably after my visit of the Euromold fair in Düsseldorf on Sept. 23rd-24th, where I will be able to see the latest technology). So it was a good opportunity to try how far - read how fine - you can go with 3D-printing. So after a few hours' work, I have an almost complete Wright Whirlwind J6-9 in 1/32 scale ... and virtual format. These are screen captures of my Solidworks designs, so, sorry, the pics are bit muddied by the light grey construction lines. I have not yet found out - did not search much in fairness - how to eliminate those from the renderings. I still have to add the pushrods, and design the front ignition harness, but this is mostly it done. If possible, I'll have the engine block, including the intake manifolds and the pushrods, printed as one part, and the cylinders printed separately (they have been designed this way) So, whilst I finish the design work, and get the parts printed somewhere, I have decided to move on to the rest of the kit. I'll come back to the engine when I have a return on my printing trials. First thing first, my review stand corrected. The kit, besides the engine, is not as accurate as I initially described, and not only because of the shape of the fuselage. This one is 6 mm too long, at the level of the cokpit ( sorry guys, the 6 mm plug cannot be used on P-39 kits ), is too shallow by 2 mms, and too narrow at its maximum width - the firewall - also by 2 mms, and also too shallow at the level of the headrest, with a wrong cross-section for it anyway. Plus the cockpit is thus too far back, and the wing trailing edge karman is far too long as well. This is actually potentially good news, as we now have a place to start surgery. Here is what I did to correct it : 1) Cut the fuselage at the level of the kit's headrest. 2) Make a new cut 6 mm ahead of the first one, in the middle of the cockpit opening 3) Sand away (took me 1 minute with my Dremel sanding disk) the extra width of the rear fuselage. It should be only 22 mm at the level of the headrest. The resin is thick enough to allow this decrease whilst keeping enough material for strength. I actually sanded the half rear fuselage to 10 mm : as the result is a flat face whereas the rear fuselage sides are slighty convex, I will add back material to achieve the proper cross-section whilst keeping the overall width OK. 4) Make a new cut for the front cockpit opening, 6 mm ahead of the kit's one 5) Reinforce the bottom of the fuselage internally with some epoxy putty 6) Make a saw-cut (with RB Productions' fine saw) of the front fuselage side, along the wing Karman panel line, and roughly 35 mm long, starting from the rear end. 7) Push the fuselage side 2.5 mm inside (as measured at the rear saw-cut). In this area, the fuselage side is pushed inside by the whole width of the resin, hence the need to have previously added some reinforcement with epoxy putty. CA-glue the new pinched fuselage side to the epoxy mating surface inside. The Karman will have to be re-shaped from the original over-thick one. 8) The missing height and width of the fuselage are on top and and on the sides, slightly above the center line defined by the horizontal axis of the engine plug hole, by 1 mm. 9) I glued 80 thou (2 mm) strips on the top and sides of the fuselage to have some references for the added material. The sides were sanded and faired-in to 1mm thickness at the widest point of the cross-section. I now have a rough "profile" and plan view fro adding material. This is how it looks so far: Front fuselage half, with inside epoxy putty reinforcement, and pinched-inside fuselage sides Front fuselage half, with the pinched-in side (look at the "step" at the level of the rear karman line), and added strips for extra height/depth indications Comparison between the left fuselage half, "butchered" and the still-intact right one. You can see it is shorter and the cockpit opening has been moved forward. Finally, comparison from above between the left modified fuselage and the original right one from the kit. You can see the pinching-in of the fuselage from the firewall to the rear of the cockpit. The left fuselage is now correct in plan view. I now have to fill-in with epoxy putty the front fuselage sides, to the level of the strips. The inside of the cockpit will then be thinned down, and the phony and overthick ribs erased. The rear headrest fairing will be beefed-up un a similar fashion. More soon. Hubert PS edit : A correction on a correction ... The kit's overall fuselage length is actually OK, give or take 1 mm. So my first accuracy check of overall dimensions was alright after all. BUT, having done the beefing-up of the front fuselage sides, the problem lies with the position of the wing relative to other elements such as the cockpit, the cowling, the headrest, etc. The wing is actually some 5 mm too far forward. Hence also the too long Karman. So my correction is valid, and the only way to get an accurate fuselage: it will in effect bring the wing some 5/6 mm backwards. I found this out while pasting the forward fuselage with epoxy putty: I had to bring foward the firewall cross-section (the largest of the aircraft) et add a plug to the front fuselage to get a correct profile and plan view. Edited September 10, 2015 by MostlyRacers Out2gtcha 1 Link to comment Share on other sites More sharing options...
Hubert Boillot Posted September 10, 2015 Author Share Posted September 10, 2015 (edited) A quick pic to illustrate my Post-Scriptum above about the position of the wings relative to the rest of the fuselage. The two halves (right on the pic - left half - = corrected, left on the pic - right half - = original kit fuselage) are roughly aligned along the rudder line. You can see they are almost the same length, but that my sugery has moved the wing-root back by some 5/6 mms. The corrected fuselage half is still in two parts, held together, and they are not perfectly aligned on the central axis btw. Hubert Edited September 10, 2015 by MostlyRacers Out2gtcha 1 Link to comment Share on other sites More sharing options...
Out2gtcha Posted September 10, 2015 Share Posted September 10, 2015 WOW Hubert! Awesome problem solving Hubert Boillot 1 Link to comment Share on other sites More sharing options...
Guest Peterpools Posted September 10, 2015 Share Posted September 10, 2015 Hubert Brilliant solutions and some exquisite modeling. Keep 'em coming Peter Link to comment Share on other sites More sharing options...
Spads57 Posted September 10, 2015 Share Posted September 10, 2015 Hubert, This is an awesome project thread my old friend. Outstanding Master Level skill and craftsmanship. Highest Regards, Gregory Jouette Hubert Boillot 1 Link to comment Share on other sites More sharing options...
LSP_Kevin Posted September 11, 2015 Share Posted September 11, 2015 You're really giving that thing some tough love, Hubert! Kev Hubert Boillot 1 Link to comment Share on other sites More sharing options...
Hubert Boillot Posted September 11, 2015 Author Share Posted September 11, 2015 (edited) WOW Hubert! Awesome problem solving Hubert Brilliant solutions and some exquisite modeling. Keep 'em coming Peter Hubert, This is an awesome project thread my old friend. Outstanding Master Level skill and craftsmanship. Highest Regards, Gregory Jouette You're really giving that thing some tough love, Hubert! Kev Thank you, guys. Happy you enjoy it. Greg, good to see you more active every day. Although there is not much I could do, you got me worried ... (Almost) Finished designing the engine with the pushrods, but for the ignition harness. Here is how it looks. I just realised, looking at the pics, that i have forgotten the sparks recesses on both sides of the head. Need to add those before I can say it's over .... FYI, overall diameter in 1/32 scale is roughly 35 mm, i.e. 1 2/5 " ... Hubert Edited September 11, 2015 by MostlyRacers Harold, Tnarg, Lars Befring and 1 other 4 Link to comment Share on other sites More sharing options...
Tnarg Posted September 11, 2015 Share Posted September 11, 2015 It would really be nice to have an alternative to Wms Bros engines for so many of the 30's planes. I hope that you can find a way to produce these with the detail you desire. We seem to be close to the limit of resolution on too many of the details in 1/32, but the technology is improving every day. Thank you for letting us see your progress. Tnarg Link to comment Share on other sites More sharing options...
Hubert Boillot Posted September 11, 2015 Author Share Posted September 11, 2015 (edited) It would really be nice to have an alternative to Wms Bros engines for so many of the 30's planes. I hope that you can find a way to produce these with the detail you desire. We seem to be close to the limit of resolution on too many of the details in 1/32, but the technology is improving every day. Thank you for letting us see your progress. Tnarg Thank you for your interest, Tnarg. The Whirlwind 3D design took me a lot less time than my ongoing P&W R-985 Wasp Jr, where I have been stalled lately on the design of the head 'vertical' fins and rocker covers. In fact I changed some parameters on the cylinder design and height, with anoting rippling effects on the head design. Methinks I'd be better starting from scratch again rather than reviewing the parameters and relations one by one.On the R-985, I had also to re-calculate the various dimensions, using the docs I had, including maintenance manuals. Plus I went to extreme detailing of the whole engine, including the accessories such as the Scintilla magnetos and Stromberg carburetor. But there are so many projects for which I can use the R-985 : the Gee Bee R2, the Sikorsky S-39, the Beech Staggerwing, the Beech 18, the Kingfisher, for instance, to name a few ... For the Whirlwind, I was lucky to acquire some old Wylam drawings, which have been a tremendous help to avoid multiple 'guesses' and cross-checks on key dimensions. Now that I have the basic cylinder design, I intend to produce the variants with the side exhaust port, facing aft (the Sparrowhawk engine IIRC) or forward (the Trimotor for instance). Plus it will be easy to design a block for a J6-7 or Even J6-5 ... As far as 3D printers are concerned, my aim is set on a SLA printer with a XY resolution of 37 microns or less, and a flexible Z resolution of at least 15 microns (although 30 seems enough most of the time). The issue is to find one with a big enough working area for a meaningful production. Plus my investment budget is not unlimited : I am not yet ready to invest 90 000 € in such a machine for instance... Hubert Edited September 11, 2015 by MostlyRacers Link to comment Share on other sites More sharing options...
Tnarg Posted September 11, 2015 Share Posted September 11, 2015 That sounds incredible, especially if we could obtain more of the P&W engine alternatives. You could scale those up to 1/24 should we want to go there. Way too much fun. Would you be interested in selling these as cast or as printed objects? I am assuming printed. The answer is Yes for the question: Would we use these on a Sparrowhawk, Trimotor, S-39, Gee Bee, Kingfisher? and on and on. Tnarg Link to comment Share on other sites More sharing options...
Hubert Boillot Posted September 11, 2015 Author Share Posted September 11, 2015 (edited) That sounds incredible, especially if we could obtain more of the P&W engine alternatives. You could scale those up to 1/24 should we want to go there. Way too much fun. Would you be interested in selling these as cast or as printed objects? I am assuming printed. The answer is Yes for the question: Would we use these on a Sparrowhawk, Trimotor, S-39, Gee Bee, Kingfisher? and on and on. Tnarg My goal is to sell them, as part of a business development for my company ... The jury is still out between cast or printed production. The master would be printed, for sure. If the working area is big enough to produce more than one part on the printer, than printed would be the choice ...For the forthcoming DH-89, I'll probably print the seat frames, and some cockpit details and the wheels, at least as masters for the latter two ... Hubert PS: the R-985 cylinders could also be used for a P&W R-1535, as used on the Hughes H-1 . Next on my to-do list is the Wright R-1820. I am annoyed that Vector have messed-up the angle between the cylinders, to leave room for a (poor) representation of the oil sump between the two lower cylinders. This has in effect stalled my Gulfhawk G-22 build (plus other reasons, in all honesty) for the last 4 years ... For the R-1820, a 1/18 version could be envisioned, for a Dauntless for instance (hey, Rich ? ) Edited September 11, 2015 by MostlyRacers Link to comment Share on other sites More sharing options...
Hans Posted September 12, 2015 Share Posted September 12, 2015 Beautiful work, Hubert! Link to comment Share on other sites More sharing options...
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