Fritag Posted March 13, 2015 Share Posted March 13, 2015 Presumably the rear extension is solid frame not clear plexi? My thoughts would be these. (1) Trim the rear extension off. Too hard to mould integrally. (2) Cut/sand the milliput master down until it is exactly the size of the canopy using the canopy as a guide - like this: (3) Then add a spacer to the bottom of the master thus to get the bottom of the canopy away from the grid on your vac box: (4) Then for the vac forming process add blue tack at either end of the canopy thus - ensuring that the blue tack doesn't extend to the edges of the canopy but is a but 1mm inside it. Alternatively you could use sprue or plastic cared at the ends - but the blue tack is removable after the vac forming and helps you get the master out of the mould. Then after you've vac formed it you will have a convenient guide at both ends of the canopy and underneath it - where the PETg has been sucked around the edges of the master to conform to the blue tack at either end and the spacer underneath - which you can simply cut close to and then finish off by sanding on a flat surface and easily check progress by popping the mould over the master from time to time. No need for black lines etc. Hs worked for me over the past couple of builds. 1 Link to comment Share on other sites More sharing options...
perdu Posted March 13, 2015 Share Posted March 13, 2015 And there we have proof positive that Fritag has already begun working his next project That has to be a Hawk canopy getting the lurve treatment from the plastimeister Twice or is it three? And yes G that is exactly what I would suggest too make the frame to do all the physical opening and closing bit, make the glazing to look through Just like my Jaguar unit 1 Link to comment Share on other sites More sharing options...
Fritag Posted March 13, 2015 Share Posted March 13, 2015 Just playing with bits and bobs Bill - not really started G - had a further thought. You could mould the rear extensions integrally by modifying my method. Trim the rear of the miliput to conform to the back of the canopy and around the rear extension - so the rear extensions form a step shape in the milliput. Then proceed as above. Reasonable chance you'll capture them in the vac forming. If not - no harm done; just trim off the step and proceed as above 1 Link to comment Share on other sites More sharing options...
dr_gn Posted March 13, 2015 Author Share Posted March 13, 2015 (edited) ] Edited August 27, 2017 by dr_gn 1 Link to comment Share on other sites More sharing options...
perdu Posted March 13, 2015 Share Posted March 13, 2015 Please do take Steve's advice re: the overhanging, presently cut away sections Put in some kind of 'filler' to encourage the moulded sheet back past the undercut blutak sounds like a good throw-away fit for that task Looking forwards to this immensely doc b Link to comment Share on other sites More sharing options...
dr_gn Posted March 13, 2015 Author Share Posted March 13, 2015 Yeah Ill use the Blutac as suggested - theres still plenty to do on the plug. I didnt have any mr.surfacer spray - does tamiya fine primer work ok as a final polish coat? Link to comment Share on other sites More sharing options...
perdu Posted March 14, 2015 Share Posted March 14, 2015 I think any finish you can polish to a deep shine will do I think Tamiya primer is such a product, but I have never polished it to use as a surface polisher for moulding I think it is going to work and you will be showing me some rapid advances over my old fashioned techniques I cant wait b (see how much thinking you got me doing?) Link to comment Share on other sites More sharing options...
dr_gn Posted March 14, 2015 Author Share Posted March 14, 2015 Stupid tolerances? Like microns? At work? For free? Sounds like fun to me! Cheers, Bill We've got a Sauer Ultrasonic 10 machine in our department, and the guys can get it to about +/- 10 or 15 microns, just messing about. The only problem is inspecting/checking anything less than that (not that we're exactly short of CMM's at work! http://uk.dmgmori.com/products/ultrasonic/ultrasonic-universal/ultrasonic-10#Intro Link to comment Share on other sites More sharing options...
dr_gn Posted March 14, 2015 Author Share Posted March 14, 2015 (edited) Got] Edited August 27, 2017 by dr_gn 1 Link to comment Share on other sites More sharing options...
perdu Posted March 14, 2015 Share Posted March 14, 2015 That is the real deal G Soon be finished now Link to comment Share on other sites More sharing options...
dr_gn Posted March 14, 2015 Author Share Posted March 14, 2015 On the Vivak technical data sheet, it says the moulds should not be polished, but given a matt finish to avoid "impressions on the formed part". https://www.bayersheeteurope.com/index.php/fuseaction/download/lrn_file/mf0141_e_120816.pdf Link to comment Share on other sites More sharing options...
perdu Posted March 14, 2015 Share Posted March 14, 2015 They don't know that you are intending to get totally transparent optically good canopies, much of their PETg sales are for packaging food and fancy goods Give it a go without the datasheet's advice first You are getting rid of imperfections in the moulding surface by smoothing down remember, I suspect shiny will occur anyway so I wouldn't worry 1 Link to comment Share on other sites More sharing options...
Tomoshenko Posted March 14, 2015 Share Posted March 14, 2015 For some reason I've missed this build. Just finished reading through - took several sessions. Can't even begin to describe which things I like as there is so much. Really like the attention to micro detail, and the overall realistic scaled look you've created. Brilliant. 1 Link to comment Share on other sites More sharing options...
dr_gn Posted March 14, 2015 Author Share Posted March 14, 2015 (edited) On 14/03/2015 at 4:49 PM, Tomoshenko said: For some reason I've missed this build. Just finished reading through - took several sessions. Can't even begin to describe which things I like as there is so much. Really like the attention to micro detail, and the overall realistic scaled look you've created. Brilliant. M]]I'll le] Edited August 27, 2017 by dr_gn 3 Link to comment Share on other sites More sharing options...
eng Posted March 14, 2015 Share Posted March 14, 2015 Come on, hurry up! This is rather cool, I can't wait to see how these canopies are going to turn out. By the looks of that plug I'm certain you will end up with something far superior to the kit canopy. How did you decide to do the lower canopy rails in the end? Internally or externally? I really need to go and read back a few pages. Will be jumping between BM and the BBC Sport F1 page tomorrow at work I think, eh and working really hard as well.....mmmm. Fingers crossed for you, this has been a cracking build from start to finish. Eng 1 Link to comment Share on other sites More sharing options...
dr_gn Posted March 14, 2015 Author Share Posted March 14, 2015 Come on, hurry up! This is rather cool, I can't wait to see how these canopies are going to turn out. By the looks of that plug I'm certain you will end up with something far superior to the kit canopy. How did you decide to do the lower canopy rails in the end? Internally or externally? I really need to go and read back a few pages. Will be jumping between BM and the BBC Sport F1 page tomorrow at work I think, eh and working really hard as well.....mmmm. Fingers crossed for you, this has been a cracking build from start to finish. Eng Yeah, I'll be trying this after F1 in the afternoon I guess. The kids and me are making lunch and tea for the missus for Mother's day, so it will have to work around all that. The lower rails will have strips added to the outside (i.e. doubled up along the lower edge). The canopy hoops will wrap around and but up to them. Hopefully. 1 Link to comment Share on other sites More sharing options...
eng Posted March 14, 2015 Share Posted March 14, 2015 Sounds good Dr, I'm sure this'll work out perfectly. Have a good one tomorrow. Eng Link to comment Share on other sites More sharing options...
Fritag Posted March 14, 2015 Share Posted March 14, 2015 M And on the vacuum box, surrounded by Blutac as a sacrificial run out area. Blutac needs a bit more coaxing into some of the gaps, but it's not too far away now: Master looks excellent G. If I were you tho, I'd press the blue tack back a little from the edges. So that it's about 0.5 to 1mm or so smaller than the master all round. That'll give you better defined edges to the vac formed canopy which'll make it easier to trim and sand to the perfect shape. 1 Link to comment Share on other sites More sharing options...
dr_gn Posted March 14, 2015 Author Share Posted March 14, 2015 Master looks excellent G. If I were you tho, I'd press the blue tack back a little from the edges. So that it's about 0.5 to 1mm or so smaller than the master all round. That'll give you better defined edges to the vac formed canopy which'll make it easier to trim and sand to the perfect shape. OK thanks, I will. It still needed a bit of work on the BluTac before giving it a go. TBH I assumed the vacuum, would pretty much do that (squash the blutac in a bit) for me anyway. 1 Link to comment Share on other sites More sharing options...
Ascoteer Posted March 14, 2015 Share Posted March 14, 2015 Looking good G 1 Link to comment Share on other sites More sharing options...
dr_gn Posted March 14, 2015 Author Share Posted March 14, 2015 For some reason I've missed this build. Just finished reading through - took several sessions. Can't even begin to describe which things I like as there is so much. Really like the attention to micro detail, and the overall realistic scaled look you've created. Brilliant. Thanks very much - I just had a look at your Hunter thread; you must know better than most about the agony and the ecstacy of 1:72. Plenty of both in here, I really hope the canopy works... 1 Link to comment Share on other sites More sharing options...
dr_gn Posted March 14, 2015 Author Share Posted March 14, 2015 Looking good G So far...Moment of truth tomorrow. At least until the next moment of truth. BTW, I made a name card for it, to put on the wooden base if/when it gets finished. I assumed ZA492 was from 617 Sqdn., RAF Lossiemouth at the time of the Derwent flypast (I hiked miles to see it - 17th May 2013). I assume it's right? It occurred to me that even though the fin was painted for the 617 anniversary colour scheme, it might not in fact have been a 617 Tornado from Lossiemouth at all. Pretty sure it was, but it's the kind of daft thing I'd easily get wrong. Link to comment Share on other sites More sharing options...
Cheshiretaurus Posted March 15, 2015 Share Posted March 15, 2015 master looking good, I've been using Vivak as well and read that bit about not polishing too although I have had the same results whether polished or matted. Hoping to test my Meteor T7 mould tomorrow. 1 Link to comment Share on other sites More sharing options...
Ascoteer Posted March 15, 2015 Share Posted March 15, 2015 G I can ask the Sqns if you would like 1 Link to comment Share on other sites More sharing options...
perdu Posted March 15, 2015 Share Posted March 15, 2015 (edited) OK thanks, I will. It still needed a bit of work on the BluTac before giving it a go. TBH I assumed the vacuum, would pretty much do that (squash the blutac in a bit) for me anyway. The trouble (did you really think there'd be NO trouble?) is that the vacuum also gives up without trying At least you are getting nigh on as much help as there can be in here pull it back enough to give a slight lip W I N Edited March 15, 2015 by perdu 1 Link to comment Share on other sites More sharing options...
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