maharrin Posted June 25, 2016 Share Posted June 25, 2016 This keeps getting better, Craig. The aluminum sheet and pulley system make this area shine. I love the level of detail, outstanding! brahman104 1 Link to comment Share on other sites More sharing options...
airscale Posted June 25, 2016 Share Posted June 25, 2016 superb my friend, you have clearly mastered litho you must look at those pics as we do and think that looks bloody marvelous loving watching this come together Peter brahman104 1 Link to comment Share on other sites More sharing options...
brahman104 Posted June 26, 2016 Author Share Posted June 26, 2016 Thank you for your kind words Gentlemen! Just adding details here and there. I am fortunate to have a couple of really good pics of the area I'm doing right now, and although they are invariably of G models I'm pretty confident that the control concept didn't change too much. I also have the IPC for the G model so I'm more or less cross referencing that for a "blended" solution. Still looks sooo much better than that first effort I'm now even thinking of redoing the seats in litho as they'll look a lot nicer. You can really go to town with this stuff..... sometimes you just have to get creative with how you do it..... So on that note... I'm going to try a concept here. I've made a male and female "die" that I'm hoping to be able to press the litho between in a vice and all going well it will take the shape. I have made the male part slightly smaller to allow for material thickness. The printed plastic in this sense is extremely tough and shouldn't crush, but we shall see. I've also made a "rib" shape just to try something else. If this works this could be the doorway to a whole new world of compound curves in metal.... Imagine the possibilities!!!! Update to follow soon hopefully! Craig TorbenD and Derek B 2 Link to comment Share on other sites More sharing options...
ClumsyDude Posted June 26, 2016 Share Posted June 26, 2016 Looks great Craig. My ignorance of 3D work is vast, so pls forgive if this is a stupid question - as far as I can tell your male and female dies are the same size. Does the male part need to be slightly smaller to allow for the width of the material you're pressing? Jim Link to comment Share on other sites More sharing options...
brahman104 Posted June 26, 2016 Author Share Posted June 26, 2016 (edited) Hi Jim, My ignorance on the subject is also vast, this is only a concept, but it seems feasible. You are correct, although the pictures probably don't really show it, I have reduced the measurements of the male part by a little more than the material thickness, so theoretically that should be enough. The sphere shape is around 20mm in diameter and the "rib" is 1.5mm in depth. I have no idea how much "draw" I can get away with and in all honesty I think I'll be pushing my luck with the sphere, although I am going to try it pewter sheet as well as litho, just to compare the two. Excellent question though mate. I'm really looking forward to seeing how this turns out. It may take some time to perfect, but I think I might onto something here..... Stay tuned! Craig Edited June 26, 2016 by brahman104 ClumsyDude 1 Link to comment Share on other sites More sharing options...
brahman104 Posted June 27, 2016 Author Share Posted June 27, 2016 Alright, so here's the results of the first, albeit very quick, testing. This is how the "dies" turned out. When viewed from the side, this was the amount of "draw" I was asking of the metal, about 10mm. I had an idea this might be too much for it. Test No. 1 - Litho plate (annealed) Pretty much as I expected, the litho is too hard for something like this. I may have been able to get something like a 3mm draw, but I think that would have been about it. Test No. 2 - Tin sheet And here's what it did in the "rib" The Tin sheet faired markedly better, but suffered some rather severe buckling around the outside. Not bad, keeping in mind I did not do this in stages, this is just one press. Test No. 3 - Pewter sheet Now we're getting somewhere! No surprises here, Pewter was the best of the lot. I can't really imagine too many places where I would be trying to make anything this "severe," but it's good to know what it can do. The other point I was thinking about is that Maybe instead of the female side, I should use some medium hardness rubber to "push" the male part and sheet into.... It may be a bit more gentle in the forming process. An interesting little side experiment and it shows much potential.... just one more application of 3D printed technology! Stay tuned for more Craig allthumbs, TorbenD and Derek B 3 Link to comment Share on other sites More sharing options...
allthumbs Posted June 28, 2016 Share Posted June 28, 2016 (edited) Great looking project Craig...lots of cleverness and skill on display here. Rich Edited June 28, 2016 by allthumbs brahman104 1 Link to comment Share on other sites More sharing options...
Hubert Boillot Posted June 28, 2016 Share Posted June 28, 2016 Interesting experiment. I think you need to find some way to hold the peripephery of the sheet to the female part, in order to avoid wrinkles. In essence you need to stretch the metal, rather than draw some metal into the cavity ... Now this is easy to say when you are 16 000 kms away from the experimental shop Hubert brahman104 1 Link to comment Share on other sites More sharing options...
ClumsyDude Posted June 28, 2016 Share Posted June 28, 2016 Awesome stuff Craig. Loving it! Jim brahman104 1 Link to comment Share on other sites More sharing options...
brahman104 Posted June 28, 2016 Author Share Posted June 28, 2016 Interesting experiment. I think you need to find some way to hold the peripephery of the sheet to the female part, in order to avoid wrinkles. In essence you need to stretch the metal, rather than draw some metal into the cavity ... Now this is easy to say when you are 16 000 kms away from the experimental shop Hubert Good thought there Hubert and I do agree with you, and there are certainly many ways of doing this. My next step is to try and replicate a kit part, say the leading edge/fuselage fillet and see how that goes. It may take a bit of puddling around but I think it will work. In the meantime, I'm going to do some research on youtube to see how ribs etc are made in the big industrial presses. I'm also going to try (because I can) doing a form for the centre of the control wheels and see how that turns out. Considering the part is pretty thin without much draw I think it will be okay, especially in Pewter Stick around and see what happens next.... Craig Link to comment Share on other sites More sharing options...
airscale Posted June 28, 2016 Share Posted June 28, 2016 very, very interested in this experiment looks like it has many, many applications - especially if you can design & print in house I tried it with the nosecone on my tigercat by making both halves in resin and pressing and got pretty good results - in the end I just hand worked the metal over the male form as I kept getting wrinkles & tears too one thing you might try on the fuselage former is a two stage press - the first are all rounded corners to effectively deform the metal loosely into the shape (this one does the most work / introduces the most stress) and then follow that up with the straight edged 'real' former. That way the straight edges are not acting as cutting tools during the most stressful part of the process and you avoid tears the other thing to try might be again using a rounded press mould to get the basics and then hand working the metal onto the real former - that way you can see wrinkles developing and chase them out, and can form good angled features by using wooden tools - I use coffee stirrers from starbucks etc another one may be to try some lubrication on the metal to stop it getting hung up - maybe smear some oil on the press parts.. anyways - whatever you do I will be watching & learning (as we all will) and have a notebook to hand to shamelessly steal your pioneering ideas Peter Link to comment Share on other sites More sharing options...
brahman104 Posted June 29, 2016 Author Share Posted June 29, 2016 Some brilliant suggestions there Peter, thank you! I understand exactly what you mean there. I did have the feeling I was pushing the limits of the metal just a little too much, but you gotta start somewhere hey? Noted as you did about the cutting action of the close tolerance dies, this may become an advantage later on for operations such as notching of ribs and the like, all of which would make life grand for mass production (I'm thinking rear fuselage details here) in the future. I'd agree that for a rib shape I should be looking at something like 3 different dies, and some cheeky lubrication here and there would not go astray either.... I really want to keep cracking on with this but life is a little busy at the moment.... Definite potential for our various projects here though mate! Cheers, Craig Link to comment Share on other sites More sharing options...
JayW Posted July 4, 2016 Share Posted July 4, 2016 Go Craig Go!! Link to comment Share on other sites More sharing options...
brahman104 Posted July 4, 2016 Author Share Posted July 4, 2016 Thanks very much Jay! This experiment is growing considerably in its scope at the moment. I've printed a modification for my photo etch bending tool and I'm making an experimental "extrusion" roller at the moment. If it works, this will open up a whole new range of possiblities with the metal work. Due to the close tolerances you can get with the Up Box, it also occurred to me today that I might be able to make some "punching" dies which will help with things like stringer cut outs in ribs etc. In all honesty, I should probably make a new topic in the hints and tips section, so I keep this thread dedicated to the B-17 itself. In any case, there'll be more to come soon, and hopefully this time spent in the R&D department will be worth it Cheers, Craig Link to comment Share on other sites More sharing options...
clarkis Posted July 4, 2016 Share Posted July 4, 2016 Craig - did you anneal the pewter before you formed it? CAN you anneal pewter? How 'bout heavy tin foil...did you try that? Carry on! Clark Link to comment Share on other sites More sharing options...
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