Mstor Posted September 18, 2019 Share Posted September 18, 2019 5 hours ago, foxmulder_ms said: Thanks... There picture over AMK model. Looks spot on even though AMK model actually has an angle. It would actually fit even better if the model was pictured better: The AMK kits looks pretty darn close in this pic. Thanks Mulder (Everyone on the show called him Mulder ). The only question I have is about the rear cockpit. The seat position doesn't appear to be lining up. One comparison pic is not conclusive, of course, but that areas bears closer scrutiny. Otherwise the shapes look real good. Like you inferred, the angle of the photo of the model may be effecting things. We need a straight on side shot. Quote Link to post Share on other sites
delide Posted September 18, 2019 Share Posted September 18, 2019 (edited) 5 hours ago, foxmulder_ms said: Thanks... There picture over AMK model. Looks spot on even though AMK model actually has an angle. It would actually fit even better if the model was pictured better: I don’t have the kit photo to do it myself, so this is just a 2 minutes work, the only point is that your overlay is not transparent enough to review any potential issue, see the noticeably different distance between the seats in my side by side picture, despite the fact that the pictures are roughly the same length. I'm surprised that you didn't notice it while doing the overlay yourself. Edited September 18, 2019 by delide Quote Link to post Share on other sites
delide Posted September 18, 2019 Share Posted September 18, 2019 (edited) 6 hours ago, ChesshireCat said: A factory drawing is not a blue print! Blueprints are accurate in shape and layout. Drawings are just a work aid, and not anything more. Gary What a factory drawing or blue print is or does, I don't think that matter here, a drawing might be based on the blue print, who knows? So in the end it might just as well match closely with the blue print/real thing. Anyway, I don’t think anyone is drawing conclusion here, but the fact that Zactoman used the drawing of A to reveal the difference in the rear canopies , which not many seems to know about, shows that the drawing is probably quite accurate and useful. Edited September 18, 2019 by delide Quote Link to post Share on other sites
Solo Posted September 18, 2019 Share Posted September 18, 2019 I have just received email from HobbyEasy about postage costs for F-14D, but they clarify that they still don't have kit, but will reach it soon. 🙂 Quote Link to post Share on other sites
delide Posted September 18, 2019 Share Posted September 18, 2019 31 minutes ago, Laurent said: Your overlay actually gives weight to the assumption that the canopy is too short and you did this without using the Grumman drawings but the photo of an actual aircraft. Materialize the rear edge of the canopy and see for yourself. I see, you're right, the overlay does suggest that the canopy of the kit is too short, it ends at about where the plexiglass of the real thing ends. Quote Link to post Share on other sites
Manuel J. Armas S. Posted September 18, 2019 Share Posted September 18, 2019 7 hours ago, Solo said: I have just received email from HobbyEasy about postage costs for F-14D, but they clarify that they still don't have kit, but will reach it soon. 🙂 Me too… The TOMCAT is NEAR Quote Link to post Share on other sites
ChesshireCat Posted September 18, 2019 Share Posted September 18, 2019 12 hours ago, delide said: What a factory drawing or blue print is or does, I don't think that matter here, a drawing might be based on the blue print, who knows? So in the end it might just as well match closely with the blue print/real thing. Anyway, I don’t think anyone is drawing conclusion here, but the fact that Zactoman used the drawing of A to reveal the difference in the rear canopies , which not many seems to know about, shows that the drawing is probably quite accurate and useful. Oh, but it dose! A drawing just gives you numbers and where they reside. True shapes come from blue prints, and not drawings. Ask an engineer Gary Quote Link to post Share on other sites
Zactoman Posted September 18, 2019 Share Posted September 18, 2019 30 minutes ago, ChesshireCat said: True shapes come from blue prints, and not drawings. As delide has suggested, some drawings are based on blueprints. The YF-23 drawings available through that website happen to be very accurate with a bunch of cross sections that all happen to fit within the envelope of the whole and match the various views provided in the drawings. With a typical drawing this is almost never the case. I've only done a brief check on these F-14 drawings, but they do seem to be pretty accurate. Close enough for government work (or plastic modelers) and better than any of the published drawings that I've found on the internet or in books. They certainly aren't complete though, with many external details omitted and lots of internal components included that most of us won't utilize. The general outlines and external components that are included seem to be accurate in shape and location so I'd imagine the internal components are as well. I guess we'll have to wait for @gtypecanare to provide us with those loft-llines to confirm! Quote Link to post Share on other sites
habu2 Posted September 18, 2019 Share Posted September 18, 2019 1 hour ago, ChesshireCat said: Oh, but it dose! A drawing just gives you numbers and where they reside. True shapes come from blue prints, and not drawings. Ask an engineer Ok, I am a degreed engineer with many years of experience in creating both drawings and blueprints. I have one question for you. Where do you think blueprints come from? Drawings made on either mylar or tracing paper are analogous to photographic negatives (or slides) used to make photographic prints. In this analogy the prints are blueprints made from drawings. . Now in this day and age CAD systems and large plotter printers have pretty much made mechanical drafting and the resulting real blueprints extinct, but the same truth holds - prints of any kind come from drawings. It’s not a “ chicken or egg” kind of scenario. I must say though I do not miss the smell of ammonia..... Quote Link to post Share on other sites
DIO Posted September 18, 2019 Share Posted September 18, 2019 36 minutes ago, habu2 said: Ok, I am a degreed engineer with many years of experience in creating both drawings and blueprints. I have one question for you. Where do you think blueprints come from? Drawings made on either mylar or tracing paper are analogous to photographic negatives (or slides) used to make photographic prints. In this analogy the prints are blueprints made from drawings. . Now in this day and age CAD systems and large plotter printers have pretty much made mechanical drafting and the resulting real blueprints extinct, but the same truth holds - prints of any kind come from drawings. It’s not a “ chicken or egg” kind of scenario. I must say though I do not miss the smell of ammonia..... Not an engineer, but wouldn't it make more sense if drawings came from blueprints and not the other way around? I mean, how accurate can be a drawing to drive the creation of a blueprint. And how many times can anyone draw something accurately the same at all times? Honestly asking. Quote Link to post Share on other sites
punder Posted September 18, 2019 Share Posted September 18, 2019 The thing is, most published drawings aren't based on factory blueprints, they are drawn by outsiders (for example, a graphic artist at an aviation mag, or just a fanatical enthusiast). People working with incomplete and often contradictory data. Acquiring accurate factory drawings is a lottery win. Even then, there is a lot going on in the 90 degrees between those orthogonal planes, and judgment, experience and talent come into play. Not an engineer, but I am a CAD pro, and for years now I've been modeling one particular airplane for my own amusement. Even with good drawings, excellent documentary publications and thousands upon thousands of walkaround photos, this stuff is really hard. It's not just math and geometry, it's art. Quote Link to post Share on other sites
habu2 Posted September 18, 2019 Share Posted September 18, 2019 6 minutes ago, DIO said: Not an engineer, but wouldn't it make more sense if drawings came from blueprints and not the other way around? No. Rather than re-write facts, this is copied from the wikipedia page for "blueprint" Quote A blueprint is a reproduction of a technical drawing using a contact print process on light-sensitive sheets. Introduced by Sir John Herschel in 1842,[1] the process allowed rapid, and accurate, production of an unlimited number of copies. It was widely used for over a century for the reproduction of specification drawings used in construction and industry. The blueprint process was characterised by white lines on a blue background, a negative of the original. Read here : https://en.wikipedia.org/wiki/Blueprint for the blueprinting process and the various chemicals involved. It's not that different than the more recent "Xerox" copier. You work from blueprints so that the original drawing remains unmolested. If there was ever a question on the blueprint (copy) you always refer back to the drawing (original). Only the engineer (or draftsman) can change the original drawing, and he notes any changes in the revision box with dates and initials to track the change(s). New blueprint copies are then made from the updated original for the fabricators to work from. Quote Link to post Share on other sites
Manuel J. Armas S. Posted September 18, 2019 Share Posted September 18, 2019 For me this tread is helpfull to find what I need to correct or improve, when the kit arrives. Ejections seats Wheels Hips shape Fuel probe bay GPS TARP pod Quote Link to post Share on other sites
Space Tiger Hobbes Posted September 18, 2019 Share Posted September 18, 2019 (edited) In short, some things may be lost/modified in the "sausage-making" between official blueprint and drawings which may have other purposes/customers. Then, too, times have changed and there are proprietary and other reasons a company might not provide accurate, detailed factory plans for a high-performance weapon that millions were spent to spec, design and test. Edited September 19, 2019 by Space Tiger Hobbes Quote Link to post Share on other sites
Mstor Posted September 19, 2019 Share Posted September 19, 2019 2 hours ago, habu2 said: You work from blueprints so that the original drawing remains unmolested. If there was ever a question on the blueprint (copy) you always refer back to the drawing (original). Only the engineer (or draftsman) can change the original drawing, and he notes any changes in the revision box with dates and initials to track the change(s). New blueprint copies are then made from the updated original for the fabricators to work from. I know this is all straying a bit off topic (well more than a bit), but the idea of version control is interesting to me. In software development (if the company is smart), they institute a strict process of version control, where all changes to software are documented and copies of the software at its various states are saved. Did companies like Grumman keep copies of the plans at various states like they do with software these days? I'm talking about back in the day of physical paper plans and blueprints. I'm sure that using CAD software a similar system of version control can be maintained fairly easily. Just wondering if somewhere in dusty old Grumman vaults (that is whoever owns Grumman these days) there are reams of plans documenting the evolution of an aircraft like the F-14. Quote Link to post Share on other sites
habu2 Posted September 19, 2019 Share Posted September 19, 2019 (edited) 1 hour ago, Mstor said: Did companies like Grumman keep copies of the plans at various states like they do with software these days? I'm talking about back in the day of physical paper plans and blueprints. I didn’t work at Grumman, but yes, copies were kept. The originals, usually pencil on paper or ink on mylar, were copied at each revision level. These copies were called sepias, made in a manner similar to blueprint copies, except the sepia paper was translucent (like paper or mylar) and could also be used as a source for blueprint copies. Originals and sepias, usually E sized (30” x 42”) were stored in large filing cabinets (some horizontal, some vertical). Good info here: https://en.m.wikipedia.org/wiki/Shop_drawing Each drawing was assigned a specific number. The architectural projects I was on used a three part numbering convention where the first group identified the building/project, second was the drawing type (structural, electrical, plumbing etc) and the third was a sequential number. This, with the revision process, was a form of configuration control. Later in my career I was a software configuration control manager and my experience on shop drawings made it easy to treat software in much the same way. I guess the point of this topic digression is that blueprints are valuable references, but they are dimensionally and geometrically accurate copies of a specific revision level of the original drawing(s). . Edited September 19, 2019 by habu2 late night typos Quote Link to post Share on other sites
dryguy Posted September 19, 2019 Share Posted September 19, 2019 Would a company such as Grumman sub-contract airframe parts to other manufacturers? If so, how tight were the tolerances on actual shape? Does the possibility exist of there being subtle shape differences from airframe to airframe due to different manufacturers? That would really suck if it did- so i certainly hope not. Quote Link to post Share on other sites
DIO Posted September 19, 2019 Share Posted September 19, 2019 For me, although I love AMK F-14, is easier to accept that there are some minor issues with the kit instead to try and figure out under which circumstances would the blueprints or drawings be wrong! Same issues like with any other kit I guess. Pretty sure that the other "perfect kit" has some of those too... Will soon be comparing the two and honestly, I can't wait! Quote Link to post Share on other sites
habu2 Posted September 19, 2019 Share Posted September 19, 2019 Subcontracting is definitely the norm. The F/A-18 is probably the best example at a high level. Northrop manufactures the mid & aft fuselage and McAir - Now Boeing - manufactures the nose and wings. LTV built a large part of the Rockwell B-1B fuselage, LTV also built the fuselage of the Lockheed S-3. There are many more examples. Any manufactured part has manufacturing tolerances, they are called out in the drawings. The tolerances depend on the specific part and application. Aircraft tolerances might be in the order of hundredths of inches, buildings might be +/- an inch or so. There is also the concept of stack tolerances, the accumulation of all the individual part tolerances in the assembled part. Quote Link to post Share on other sites
Greg Long Posted September 19, 2019 Share Posted September 19, 2019 239 pages going on on on on and on, when you've got the kit in your hands then have your 2 cents worth or in most cases with you lot $2 worth and that is still not enough Quote Link to post Share on other sites
ChesshireCat Posted September 19, 2019 Share Posted September 19, 2019 5 hours ago, habu2 said: Ok, I am a degreed engineer with many years of experience in creating both drawings and blueprints. I have one question for you. Where do you think blueprints come from? Drawings made on either mylar or tracing paper are analogous to photographic negatives (or slides) used to make photographic prints. In this analogy the prints are blueprints made from drawings. . Now in this day and age CAD systems and large plotter printers have pretty much made mechanical drafting and the resulting real blueprints extinct, but the same truth holds - prints of any kind come from drawings. It’s not a “ chicken or egg” kind of scenario. I must say though I do not miss the smell of ammonia..... In the case of drawings, they come after blue prints. As I said they are a work aid, but not exact. If you know what your doing, you can reconstruct from a drawing, but not always. By the way, are you aware that CAD wasn't used in the late sixties and very early seventies? That's when it was done with a French curve and a series of gauge lines. Or similar to developing an involute. Glt Quote Link to post Share on other sites
habu2 Posted September 19, 2019 Share Posted September 19, 2019 If you want to believe drawings come after blueprints just keep telling yourself that. And yes I’m aware of the timeline history of CAD. I still have my T-square, compass, dividers and yes a few french curves from my time as a draftsman, and I have personally made hundreds if not thousands of blueprints from drawings. I was also doing computer aided design on aircraft programs in the early 80s. Been there done that seen the world from both sides now. There are many here who have worked on real F-14s, not just plastic models of them. I’ve worked as a draftsman and a CAD designer on aircraft programs and I stand by what I stated. Blueprints are made from drawings. Quote Link to post Share on other sites
ya-gabor Posted September 19, 2019 Share Posted September 19, 2019 It is fascinating to read the discussion about what is and what is not a blue print or a factory drawing or in this case an internal arrangement draft. Interesting but getting very far from some real questions of a plastic kit. It seems that no real F-14 Tomcat survives to this day in the great US of A. If there are any, has anyone ever considered getting up from the armchair in front of the computer and actually going out to have a closer look at one, do some simple measurement?? There is no need for a 3D scan (although it would be great) just some basic measurements and taking photos of that so much discussed tail or other questionable parts of the real aircraft and compare it to the kit. Some instant and very authentic answers could result from such a visit! Just asking. Around here in Central Europe there are not too many Tomcats (I mean real ones) although not far in the middle east there are still some operational ones. I am not sure if they would like me going up to them with a measuring tape or a laser measurer. (I think I would have any problems of spending my free time in the next few years solved immediately) 😊 Best regards Gabor Quote Link to post Share on other sites
Mstor Posted September 19, 2019 Share Posted September 19, 2019 6 hours ago, habu2 said: I didn’t work at Grumman, but yes, copies were kept. The originals, usually pencil on paper or ink on mylar, were copied at each revision level. These copies were called sepias, made in a manner similar to blueprint copies, except the sepia paper was translucent (like paper or mylar) and could also be used as a source for blueprint copies. Originals and sepias, usually E sized (30” x 42”) were stored in large filing cabinets (some horizontal, some vertical). Good info here: https://en.m.wikipedia.org/wiki/Shop_drawing Each drawing was assigned a specific number. The architectural projects I was on used a three part numbering convention where the first group identified the building/project, second was the drawing type (structural, electrical, plumbing etc) and the third was a sequential number. This, with the revision process, was a form of configuration control. Later in my career I was a software configuration control manager and my experience on shop drawings made it easy to treat software in much the same way. I guess the point of this topic digression is that blueprints are valuable references, but they are dimensionally and geometrically accurate copies of a specific revision level of the original drawing(s). . Thanks habu2! You answered my question perfectly. Great info. Sorry for the digression guys. Back to our regularly scheduled programming . Quote Link to post Share on other sites
Mstor Posted September 19, 2019 Share Posted September 19, 2019 5 hours ago, ChesshireCat said: In the case of drawings, they come after blue prints. As I said they are a work aid, but not exact. If you know what your doing, you can reconstruct from a drawing, but not always. 5 hours ago, habu2 said: If you want to believe drawings come after blueprints just keep telling yourself that. Just one more digression to hopefully clear up this confusion. As I understand it now, blueprints are documents that are created from the original plans (drawings). I think what ChesshireCat is referring to are drawings such as the ones Zactoman posted, that probably did come after any blueprints (and original plans/drawings) were created. A confusion of semantics? Now back to the F-14.... 1 hour ago, ya-gabor said: If there are any, has anyone ever considered getting up from the armchair in front of the computer and actually going out to have a closer look at one, do some simple measurement?? If there were one close to me, I'd would love to do just that. Unfortunately, health problems keep me pretty close to home most of the time. In any case, I am sure there are a number of F-14s on display around the USA. How easy it would be to get close enough for useful pics or scanning is something others may be more familiar with. I will say this though, the F-14 has been photographed extensively. I don't know that more photos would prove that useful. Scanning, on the other hand, would be extremely useful (IMHO). Just my two bits worth. Quote Link to post Share on other sites
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