airscale Posted June 9, 2017 Author Share Posted June 9, 2017 (edited) evening ladies thanks for stopping by and your kind words so - this is the final part of the windshield - quite a complex set of folds and a pretty tricky lip all the way around the bottom edge - it also has the de-icer spray bar in a slot on the main face.. ..the first thing was to make a femplate of the section where it meets the fuselage so it is a nice tight & clean fit - I cut a bit of plastic sheet to the angle of the windshield and worked a bit of litho until I had the exact profile... ..after transferring the shape to another sheet, I nipped the edge with some small flat tipped pliers to start forming the lip - I also maked out the folds and the slot to be cut by matching it up to the made part... ..starting to detail and add the folds... ..and the final part with the spray bar added from a wafer thin sheet of brass with holes drilled in it... ..this was then added to the assembly while taped in place on the model to get a good fit and the right position.. the rest of the framing was finished, including the rear frame with another folded lip in it... ..I checked a few references and the inside frames seem to be either green or black - TZ138 is black now and I quite like the contrast, so masked up and painted the interior after adding the interior frames.. ..it's all covered in greasy fingerprints, but I did clean it beforehand and I managed to not scratch it, or get glue or vapour where I didn't want it, so I am happy ..quite glad that is done, though it was quite fun - onto the canopy next (and that I am not looking forward to)... TTFN Peter Edited June 9, 2017 by airscale 26 Link to comment Share on other sites More sharing options...
dave665 Posted June 9, 2017 Share Posted June 9, 2017 The windshield looks stunning Peter. Better than the real thing! 1 Link to comment Share on other sites More sharing options...
CedB Posted June 9, 2017 Share Posted June 9, 2017 +1, stunning indeed. Good luck with the canopy 1 Link to comment Share on other sites More sharing options...
Pastor Rich Posted June 10, 2017 Share Posted June 10, 2017 (edited) [ -----> insert awe inspired deafening silence here because I've simply run out of words <----- ] Edited June 10, 2017 by Pastor Rich To err is human, proof readers untie! 2 Link to comment Share on other sites More sharing options...
Pete in Lincs Posted June 10, 2017 Share Posted June 10, 2017 Now there's a lovely little model all on it's own! Get them mass produced in China and make a fortune! 1 Link to comment Share on other sites More sharing options...
Nigel Heath Posted June 11, 2017 Share Posted June 11, 2017 Incredible workmanship, that front screen is amazing. 1 Link to comment Share on other sites More sharing options...
airscale Posted June 12, 2017 Author Share Posted June 12, 2017 thanks chaps & good evening so I had a blip with the canopy when I tried pulling a copy having spent all morning getting a nice glassy finish on the canopy plug, on the first pull, the sheet was not quite hot / flexible enough so I lifted it off and most of the primer surface came with it... insert lots of anglo saxon language.. the root cause goes right back to the beginning as I had made a master and built up the plinth for it to sit on from balsa, and set this in the box to pour RTV over to create the female mould - it was at this point the balsa being light and full of air made the plug turn turtle in it's box so the balsa was at the top and the canopy below. At the time I thought thats ok, I can just hold it under the surface of the rubber and still get a good mould.. problem was that because now the surface of the canopy was at the bottom, al, the little bubbles had nowhere to go so I ended up with a very pock marked master.. again, I thought thats ok, I can just fill all the holes and go from there.. FAIL, even now as I look at the finished plug, the heat must have softened the paint as these have become visible as depressions again after trying to pull that first copy.. the upshot is, I am going to get this master ready AGAIN (6th time...), and then cast a new one without all the inherent flaws and polish that up to a shine, with no primer.. I couldn't face going back to the canopy plug straight away after messing it up so I wanted a little 'get back into the groove' project that I knew wouldn't frustrate & stress me out like vacforming does, so settled on the cockpit door.. ..again I scaled the drawings, and started with the outer skin... ..after adding the rivet detail, I folded up some litho into the structure sections - imparting curves into folded beams is really tough, so settled on plastic ribs as the interior face is painted anyway.. ..the canopy slide rail forms the top part of the door structure.. ..the remainder of the structure was added including the slotted hinge area at the bottom... ..started to assemble the tiny parts for the release mechanism from tube & folded ali - the handle I had already designed as part of the PE set I did right at the beginning ..and with the mechanism added before painting - the two big rivets are just holding it all in place as I wanted to paint it and then add the bits to keep the natural metal finishes.. ..and with a pin to illustrate scale.. ..painted & assembled and with tiny springs added to the latches.. ..when fitted, it will look something like this... ..so, that was a nice little diversion - now back to that damned canopy TTFN Peter 19 Link to comment Share on other sites More sharing options...
71chally Posted June 12, 2017 Share Posted June 12, 2017 Incredible stuff, every sub assembly is an immaculate model of the real thing 2 Link to comment Share on other sites More sharing options...
Pastor Rich Posted June 12, 2017 Share Posted June 12, 2017 Peter: Do you use jewelers glasses when working on the small bits and pieces? Those door mechanisms are awfully small and I would have to have them under a glass to see them! You do realize that the perpetrators of the DOS attacks against this forum are likely green with envy and jealous beyond a measure of the sheer excellence and supreme skill on display here! Seeing it leaves them screaming "Make it stop! I can't it any longer!!" No matter how you do it, Peter, it is a privilege being able to marvel at your work and share in your trials and triumphs! Thank you for sharing your passion with the rest of us! PR 2 Link to comment Share on other sites More sharing options...
Nigel Heath Posted June 13, 2017 Share Posted June 13, 2017 Now that's just totally awesome work. 2 Link to comment Share on other sites More sharing options...
sithman Posted June 13, 2017 Share Posted June 13, 2017 LMAO! "a nice little diversion" for you,.........a holy grail for me! FANTASTIC work! Thank you for sharing! 2 Link to comment Share on other sites More sharing options...
CedB Posted June 13, 2017 Share Posted June 13, 2017 That door is amazing Peter, very realistic and it works! Great stuff Good luck with the new plug - I'm sure you'll master it (with apologies for the pun). 2 Link to comment Share on other sites More sharing options...
Max Headroom Posted June 13, 2017 Share Posted June 13, 2017 That hatch in itself should be displayed on a polished wooden plinth and displayed prominently. Trevor 4 Link to comment Share on other sites More sharing options...
dave665 Posted June 13, 2017 Share Posted June 13, 2017 I love the way you casually drop in these small projects Peter. Almost as an aside to the main build. Stunning stuff yet again! The hatch is a delight on its own. But the sum of all these parts is bewildering! Thanks yet again for sharing. 2 Link to comment Share on other sites More sharing options...
Pete in Lincs Posted June 13, 2017 Share Posted June 13, 2017 An exquisitely excellent example. 2 Link to comment Share on other sites More sharing options...
F4u Posted June 13, 2017 Share Posted June 13, 2017 (edited) Absolutely brilliant work looking really nice. Guy Edited June 13, 2017 by F4u 2 Link to comment Share on other sites More sharing options...
Nigel Heath Posted June 13, 2017 Share Posted June 13, 2017 Now I'm thinking you have a massive pin stashed away somewhere: Unbelievable stuff. 8 Link to comment Share on other sites More sharing options...
sithman Posted June 14, 2017 Share Posted June 14, 2017 THAT explains it! Real aircraft door photographed next to a modelled giant pin to give the impression that the door is 18th scale! VERY clever! The aircraft was real all along BUT all the "to show scale props" were the actual models 4 Link to comment Share on other sites More sharing options...
Pastor Rich Posted June 14, 2017 Share Posted June 14, 2017 Ah, it's a paradox. Like hiding the TARDIS inside the TARDIS! 4 Link to comment Share on other sites More sharing options...
M_Sinclair Posted June 16, 2017 Share Posted June 16, 2017 An absolute jewel you have made! And continue to make! This really does need to go on a big tour upon completion, sweeping contest after contest! -matt 1 Link to comment Share on other sites More sharing options...
airscale Posted June 16, 2017 Author Share Posted June 16, 2017 hi folks Thanks for dropping in and your kind words I am just about ready to throw in the towel.. I have sorted the master (after 3 more attempts - I now have a beautiful, smooth contiguous plug that is the perfect shape (I have since cut off the windshield part..) however, I have now pulled about 12 copies all of which failed - first I got folds in the clear plastic, sorted this by draping over the mould (and dropping vertically rather than hingeing which my homemade vacbox does)and then applying the vacuum, now I get consistently perfect shapes.. but - and I have tried 4 different PETG materials at quite horrific costs (I am about £100 in so far) and all have deformities after pulling. They start out absolutely super clear as a sheet, but after heating and pulling I get lots of little defects... they are like bubbles so I tried the recommended 4hrs of baking to get rid of any moisture - no change, I tried heating the sheet in an oven at different temps, under a grill at different temps - nothing seesm to change the end result is just a distorted optical mess full of defects I have ordered a dental vaccum tool (the blue hobby one) to see if I get a better result, but for now I am giving up what I really need is someone who knows what they are doing or a commercial outfit to do it for me - any offers or suggestions? I am going back to doing the tailwheel doors with my tail between my legs & must admit I am getting pretty pi$$ed off with it now.. TTFN Peter 4 Link to comment Share on other sites More sharing options...
Pastor Rich Posted June 16, 2017 Share Posted June 16, 2017 (edited) Hey Peter, I tend to wonder about impurities in the plastics you're using to make the canopy? Dunno, but the first person who comes to mind in the scratch build community who works on higher end processed and materials is Paul Budzik (http://paulbudzik.com/). He is a dentist by trade and uses a lot of medical tools and techniques in his approach to modeling. Just a thought. The other thing I might think to do is DIY injection molding your own canopy rather than vac them. Maybe easier to mold, sand, and polish than pulling canopies as you're doing now? (Admitted that is a rabbit hole of its own -- forgive me as I think out loud) You've come too far, there is no turning back now. Between all of us here, we should be able to come to some solution! Until then, we are privileged to see anything that you do! Carry On! Edited June 16, 2017 by Pastor Rich To err is human, proof readers untie! 2 Link to comment Share on other sites More sharing options...
milli21 Posted June 16, 2017 Share Posted June 16, 2017 Hi Peter This forum is on about the same sort of problem you are having. Might be worth a read https://www.rcgroups.com/forums/showthread.php?334760-Vacuum-forming-problems Hope you get it sorted. You've come to far to let a little canopy stop you. 2 Link to comment Share on other sites More sharing options...
dave665 Posted June 16, 2017 Share Posted June 16, 2017 Hi Peter I'm no expert here but I do know people with some knowledge of working with plastics. The image of the canopy looks to show some clouding. Is this actually in the canopy or is it an optical aberration? If there is clouding it suggests the canopy is cooling too quickly as it is being pulled. Have you tried warming the plug? Or heat the sheet a bit longer. Hard to see the other imperfections you are describing. Have you tried using 0.75mm sheet? Or will that mean the canopy will be under size? Where are you getting you sheet from? It's a lot cheaper if you buy it in 2m x 1.25m sheets (£20-£30). Some suppliers may offer a free cutting service if that's too big for you to handle. Dave 2 Link to comment Share on other sites More sharing options...
Pastor Rich Posted June 16, 2017 Share Posted June 16, 2017 Peter, Following the link shared by milli21(above) I found this shared by the publisher of the Micro-Mark book on vac-u-form: "It's true, scratches up to 400 grit don't generally show even on clear parts but they do provide a way for the air to evacuate along the surface. A polished aluminum mold, for example, will trap larger air pockets as the plastic seals off to the surface, but these "pockets" are different and much larger than tiny bubbles. All wood, plasters and most materials like Bondo and even some "high fill" primers have a fine grain or texture that provides a way for air to get out. It's a fine balance,.. you want texture, but not so much it leaves an imprint. Although seemingly smooth, plasters, for instance, will always leave a surface texture in the formed part. Any outgassing of the mold would be carried away by the vacuum, it can't really inject itself into the plastic and make bubbles. The plastic never gets that fluid. Moisture bubbles will always show up during heating and never after the part is formed. I just found out about a brand new forum site called www.hobbymolding.com and it has a forum for vacuum forming!" The gent, from the thread above, who was having the same problem you have, Peter, shared this: "I had a chance to stop by the plastics supplier this afternoon and had a chat with one of the guys. He took a look at one of my pieces and said it looked pretty good and that they have the same problem with the little pits or defects. He says it's a PETG problem. I think I'll try another source. Thanks for the link to the Hobby Molding website." My wandering mind wants to know what would happen if you use two sheets stacked at a time? This is an operation that I have a date with for my CT-114 but I'm nowhere near ready to work on that part yet. Cheers, PR 1 Link to comment Share on other sites More sharing options...
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