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Old Aug 08, 2014, 09:08 AM
The wheels touch down FIRST??
BJ64's Avatar
Australia, VIC, Melbourne
Joined Jun 2009
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I accidentally posted the following over on the wrong thread: http://www.rcgroups.com/forums/showt...1366600&page=2

Gents.... I have a problem and it's doing my head in.

I have a pretty major change between 2 cross sections (formers), and I cannot figure out how to get them to transition properly.

The intakes on my aircraft finish rather abruptly at 90 degrees to the fuselage - see pics.

BJ
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Old Aug 08, 2014, 09:11 AM
The wheels touch down FIRST??
BJ64's Avatar
Australia, VIC, Melbourne
Joined Jun 2009
25,142 Posts
This area translates to the area around Formers 13 & 14 in my DevFus Foam model.

Former 13 is where the wing glove ends and the intakes should start.

However, I can't seem to render the 3D properly using the Former sections that I have.

The Former 13 to 14 section does all sorts of weird things. I've tried different combinations of hard and soft control points. Even tried to put a 'blank' former right at the junction of the end of F13 and the start of F14 - but it still tries to 'fade out' former 14 and blend the intakes in on an angle into F13 (areas A & B in the 3D shots).

I've supplied some screenshots of the Formers and their parametes from DevFus Foam.

Any ideas? Stefano perhaps?

Any help would be greatly appreciated.

BJ
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Old Aug 08, 2014, 10:54 AM
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SteveB's Avatar
Ogden, Utah, United States
Joined Dec 2000
193 Posts
BJ,

This may not be the correct method, but here's what I do. Insert another former just forward of #14. I usually put it about 0.5mm. Then you adjust that new former to get the shape you want. I'm guessing that you want the vertical sides in #13 to continue straight back to #14. That should be fairly simple. Sorry I'm at work and don't have access to DevFus or I'd send a sample. I'll throw something together tonight after work and post it.

Curious what airplane are you going to build, maybe an SU-47?

Steve B
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Old Aug 08, 2014, 11:43 AM
The wheels touch down FIRST??
BJ64's Avatar
Australia, VIC, Melbourne
Joined Jun 2009
25,142 Posts
Thanks Steve - any 'how to' would be great.

I've tried the 'dummy former' thing, but I musn't have been holding my tongue the right way coz it turned out shyte. Made even more of a mess.

So some good ole know-how would be a bonus

...and it's an F-111 I've been playing around with for nearly 5 years now and not really gotten too far with after several different attempts.

I'm slowly getting my head around the power of DevFus Foam, but there's probably a heap of tricks and tips I haven't sussed yet.

There's a few other "grey areas" and glitches I still need to get sorted, but I managed to fudge up a nosecone using some scrap white foam I scored from a dumpster.

I really appreciate your offer to help, Steve.

BJ
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Old Aug 08, 2014, 11:52 AM
The wheels touch down FIRST??
BJ64's Avatar
Australia, VIC, Melbourne
Joined Jun 2009
25,142 Posts
PS - I noticed you mentioned inserting a dummy former about 0.5mm in front of a former you're trying to "close" (for want for better words).

How do you measure that offset so accurately?

One thing I would love to see in DevFus Foam would be a method whereby you could enter exact co-ordinates/offsets etc once you have them roughly placed where you want them in the top and side view panes.

I've only been able to click and drag the blue markers to an approximate position - and as luck usually has it, it's always just one click too far from where I actually want/need it to be. If there was some sort of pop-up box that allowed you to change the exact values numerically, it would save a lot of trial and error required in navigating to the top/side view pane...then all the way through the the 'edit formers' pane, only to find out that you're a bit too far in/out/high/low from where you need to be to get the static fixed/floating markers to be sitting when you commence to trace your former shape.

i.e. click and drag to get the approximate shape/location, but then be able to zero it in to a more exact location...

BJ
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Old Aug 08, 2014, 02:17 PM
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Ogden, Utah, United States
Joined Dec 2000
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Go to FORMERS SECTIONS SETTINGS and select EDIT FORMER. Look at the TOP LEFT SIDE of the screen and you should see a box with former numbers, positions, size, etc. Note the POSITION of #14, if should be in mm. Insert your new former just forward of #14. Farther down the left side you will see VALUES as PERCENT (%) with a checked box. The default is in % from the nose based on the fuselage length. Uncheck that box and it will display the former location in mm from the nose in the box labeled DISTANCE FROM NOSE. Then select your new former and type in the new location. Say #14 is at 400mm, put the new former at 399.5mm. NOTE: The position in the upper box you looked at earlier may say 400mm but it's actual position will be 399.5mm.

Steve B
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Last edited by SteveB; Aug 08, 2014 at 04:10 PM.
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Old Aug 08, 2014, 05:04 PM
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Ogden, Utah, United States
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I did a quick trace of your formers for this so it's just for illustration. It should give you some idea as to what I was talking about. Hopefully it'll be enough to get you going again. Good luck and have fun.

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Old Aug 09, 2014, 08:24 PM
The wheels touch down FIRST??
BJ64's Avatar
Australia, VIC, Melbourne
Joined Jun 2009
25,142 Posts
You're a lifesaver, Steve

Will give that a shot...

BJ
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